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PyPI · #1735 most downloaded on PyPI
python package for finding the timezone of any point on earth (coordinates) offline
Last release 23 days ago
11 Sep 2026
Ships fairly regularly
a new release about every 2 months
Nearly every release is documented
notes for 58 of 58 stable releases
Nothing withdrawn
no release was ever pulled
8 years old
58 releases · first in 2019
Importing timezonefinder no longer binds its submodules as package attributes. Public names are resolved lazily; import a submodule explicitly before
Breaking changes:
Importing timezonefinder no longer binds its submodules as package attributes. Public names are resolved lazily; import a submodule explicitly before accessing it through the package.
TimezoneFinderL and the shared base class no longer accept the ineffective in_memory argument. TimezoneFinder(in_memory=...) is unchanged.
The command line requires an explicit query, rows, or validate-data command. Replace timezonefinder LNG LAT with timezonefinder query LNG LAT and --stdin with timezonefinder rows.
New features:
Added timezone_ids_at() and timezone_names_at() batch lookups to both finder classes and the global API. They accept separate one-dimensional lngs and lats arrays and preserve input order. Solves issue #499.
Added timezone_ids_at_land() and timezone_names_at_land() batch lookups for land-restricted results. Solves issue #499.
Added zone_names_from_ids() for converting arrays of zone IDs after filtering, joining, or grouping them. Solves issue #499.
Added the exported NO_ZONE_ID sentinel used by batch ID lookups when on_invalid="skip" leaves an invalid coordinate in place. ID-taking methods reject the sentinel instead of treating it as a negative index. Solves issue #499.
Batch lookups accept on_invalid="skip" to preserve valid results while marking invalid coordinates; the default continues to raise. Non-numeric inputs raise TypeError. Solves issue #499.
Added zoneinfo_at() to both finder classes and the global API, returning a standard-library zoneinfo.ZoneInfo. Solves issue #502.
Added utc_offset_at() to both finder classes and the global API. Solves issue #502.
Added localize() to both finder classes and the global API for attaching the coordinate's local timezone to a naive datetime. Solves issue #502.
Added timezonefinder validate-data DIR for exhaustive, opt-in validation of custom compiled datasets. It reports incomplete and inconsistent files as validation errors and never runs on finder construction. Solves issue #500.
Changed:
NumPy arrays retained as dataset state are read-only, so mutating publicly reachable implementation arrays fails instead of corrupting later lookups.
timezonefinder can now expose its documented public surface without importing NumPy, H3, or the polygon readers until a finder-related name is first accessed.
Candidate polygons are ordered by the work needed for a full lookup, including hole checks. TimezoneFinderL therefore returns the final fallback of that ordering, not an estimate of the zone covering most of the H3 cell.
The revised shortcut ordering ships in timezonefinder-data 3.2026.3.post1, a rebuilt output from upstream 2026c rather than a falsely labelled 2026d release.
The root dependency now requires timezonefinder-data>=3.2026.3.post1,<4 so installations cannot retain older format-3 data that lacks the ordering promised by this release.
Polygon coordinates use block-packed residuals on the upstream source grid instead of fixed-width absolute values. Custom compiled data directories must be regenerated with format generation 3.
The converter rejects upstream geometry carrying precision beyond the declared source grid instead of silently rounding it.
Each boundary polygon carries a latitude block index that skips blocks whose edges cannot cross the query latitude.
Stored rings may begin at a different vertex because the converter rotates them to form tighter latitude blocks; get_geometry() still returns the same closed path.
get_geometry() and get_polygon() decode packed coordinates into returned arrays rather than returning views into stored coordinate buffers.
Boundary and hole collections use the same packed geometry path in both memory modes. Solves issue #536.
The H3 shortcut index moves from resolution 3 to resolution 4. Benchmark fixtures classified as unique or ambiguous shortcuts are therefore not comparable with earlier releases.
The shortcut index uses a new array-based format with shared candidate lists and precomputed stopping positions. Custom compiled data directories must be regenerated.
The internal shortcut_mapping attribute is removed with the dictionary-backed shortcut representation. Solves issue #477.
Duplicate enclave geometry is stored once and referenced from holes through holes/poly_ref.npy. A referenced hole returned by get_geometry() may start at another vertex or use the opposite winding while tracing the same path.
The hybrid shortcut loader retains compact read-only candidate slices rather than keeping the complete serialized shortcut buffer alive.
certain_timezone_at() and get_geometry() load the zone-position table lazily once per finder instead of reopening it on every call.
Linux wheels now target musllinux_1_2 instead of the retired musllinux_1_1 image.
Bug fixes:
TimezoneFinder.cleanup() and leaving a finder context now release the memory-mapped coordinate files before returning, including when an operation raises.
Geometry-backed operations after cleanup() or after leaving a finder context now fail instead of continuing through mappings that should have been released.
Public methods accepting zone or boundary IDs now reject negative values with ValueError instead of indexing from the end of the dataset.
coord2int no longer wraps out-of-range values silently when Numba is installed.
Source vertices are rounded to timezone-boundary-builder's six-decimal grid rather than truncated toward zero. get_geometry() therefore returns corrected source-aligned coordinates.
Shortcut compilation detects boundary edges that cross an H3 cell without either shape containing a corner, fixing missed candidates near the Lesotho border, the Strait of Malacca, and the poles.
Shortcut compilation retains a polygon when an H3 cell extends outside one of its holes despite all cell corners lying inside the hole, fixing wrong answers around Pacific atolls.
Shortcut compilation handles cells crossing the antimeridian without treating wrapped longitude bounds as empty.
The point-in-polygon C extension uses fixed-width arithmetic for slope products and no longer overflows on Windows.
pip install timezonefinder[numba] no longer carries a stale upper bound on NumPy; Numba's dependency metadata decides compatibility.
Documentation:
The README, usage guide, use cases, and bounded examples prefer context-managed finder lifetimes. They reserve explicit cleanup() for long-running services and workers that reuse one finder until orderly shutdown.
Reworked the aware-datetime and UTC-offset examples around the standard-library helpers; Windows users must install tzdata. The retained pytz example uses localize() rather than replace(tzinfo=...). Solves issue #502.
The NumPy 1 migration guidance identifies 8.2.1 as the last compatible timezonefinder release and recommends an isolated environment when a system NumPy constraint conflicts.
The reduced timezones-now documentation reports the 2026c dataset accurately and points to the vendored upstream mapping for exact release-specific counts.
The use-case documentation explains the inverted sign convention of Etc/GMT names and recommends resolving offsets through ZoneInfo. Solves issue #503. Thanks to weed33834 for PR #538.
The usage documentation states that coordinates exactly on timezone boundaries have no guaranteed side and that certain_timezone_at() may return None there.
The package comparison now states the border-correctness trade-off and directs readers to reproducible comparison reports rather than embedding transient performance claims.
Added a point-in-polygon acceleration-path report covering the C extension, Numba, and pure-Python implementations.
Internal:
Changelog fragments are filed under their final release-note section so assembly produces the grouped changelog before release curation.
Cleanup-warning tests isolate their synthetic destructor failure so later collection cannot leak a warning into the next parametrized case.
Added sampled shortcut-candidate coverage validation after dataset conversion, with replayable omission diagnostics.
Candidate polygon metadata is read through buffer views rather than repeated NumPy scalar indexing.
Hole membership first checks one union bounding box before inspecting individual holes.
is_valid_lat, is_valid_lng, and coord2int are ordinary Python functions rather than one-operation Numba dispatches.
Candidate loops read each polygon's zone ID directly instead of gathering the full candidate list into a temporary NumPy array.
HoleArray owns hole lookup, union bounds, and membership checks through ids_of and any_contains.
Hole ownership lookup returns an empty range directly rather than using a generator that catches KeyError.
FileCoordAccessor.cleanup() releases its own word view before closing the mapping; caller-held views may still defer the close.
PolygonArray captures the point-in-polygon kernel alongside the buffers it serves, allowing different acceleration paths to coexist in one process.
certain_timezone_at uses the shared shortcut candidate iterator instead of maintaining a second dispatch implementation.
ShortcutIndex owns shortcut storage and decoding instead of exposing five arrays and duplicated bit arithmetic to finder methods.
Shortcut slot addressing uses the contiguous H3 base-cell-and-digit bit field directly.
Scalar and batch lookup paths share one candidate-polygon loop.
Batch lookup preparation is memoized by shortcut entry rather than sorting coordinates by cell.
ShortcutIndex.entries_of is the batch counterpart of entry_of and is checked against it across the complete shortcut index.
Batch answer arrays use the narrowest signed dtype capable of representing every zone plus NO_ZONE_ID; data validation refuses an overflowing zone count.
Zone-ID-to-name conversion lives in ZoneNames beside the table it reads; timezone_names remains a public read-only list view.
Batch coordinate admission lives beside scalar coordinate validation and preserves their intentional treatment of None.
Coordinate bounds are declared once in timezonefinder.configs and reused by validators and diagnostics.
get_last_change_idx lives beside the shortcut builder, its only caller, and compiled values are rechecked by data validation.
Coordinate buffers are written with one NumPy vector copy using a dtype shared by writer and reader; values outside that dtype are rejected.
The converter creates paired boundary and hole output directories at their shared orchestration point.
Per-polygon zone IDs use the common vector writer.
ParseAccumulator carries converter collections and counters through the parse pipeline instead of ten parallel parameters.
The converter's zone-ID ordering invariant is enforced once and tested together with dtype, maximum-ID, and position-table rules.
Converter helpers no longer keep dead iterator, reassignment, or self-return constructs that resembled off-by-one errors.
Shortcut compilation annotations accept the actual list and array forms passed by production and tests.
Removed unused JSON and pickle helpers from scripts.utils.
Removed the unused i8 fallback from timezonefinder._numba_replacements.
Removed an unused test helper that was retained only for possible future use.
Hex.poly_candidates no longer hides an impossible uninitialized cache state behind an empty result.
Hole polygons remain part of the compiled data because zone-level candidate precedence is cyclic and cannot preserve nested-enclave answers without them. Closes issue #513.
Data updates compare a frozen sample of answers with the committed baseline.
Data updates exceeding the answer-change threshold are prepared as draft pull requests for human review rather than discarded.
Data-update answer comparison runs only for the full-with-oceans dataset whose baseline it describes.
Boundary and hole payload sizes have separate release gates; polygon counts are recorded without gating renames.
Reduced-dataset expected names are translated through a vendored, digest-checked upstream merged-zone mapping. Solves issue #334.
Removed the unused hand-maintained reduced-zone mapping.
Upstream data downloads are checked against the release asset's published size and SHA-256 before parsing.
Verified source identity is recorded in DATA_SOURCE alongside DATA_VERSION only after successful conversion.
Upstream release API reads retry transient failures and ignore stale credentials for the public endpoint.
A branch declaring unpublished data can obtain a compiled wheel from compile_data.yml instead of committing generated binaries.
Packaged boundary binaries are git-ignored and obtained from the declared timezonefinder-data wheel by local and CI bootstrap paths.
DATA_BUILD_RUN binds tests, benchmarks, builds, and publication to the same compiled data-wheel artifact.
The data-wheel handoff accepts an artifact only when its packaged inputs match the checkout; otherwise it rebuilds from a published source.
Data publication uploads the wheel tested by its update pull request rather than an independent second build.
timezonefinder-data supports consecutive PEP 440 .postN releases for rebuilt output from the same upstream boundary release.
The data package README records a concise summary for every data release, including 3.2026.3.
The code-release guard verifies that the built wheel's compatible data requirement is served by PyPI before creating the GitHub Release.
The PyPI publishing job declares both OIDC and checkout permissions.
timezonefinder uses PyPI Trusted Publishing instead of a long-lived API token. Solves issue #525.
Artifact staging is shared by one composite action, with data wheels excluded from the code publisher's staging directory.
Release tags reuse the successful master test matrix instead of running it a second time.
Tag publication verifies a successful build run for the exact commit on master.
Packaging checks validate generated wheel and sdist metadata as well as repository-backed essential files.
Packaging exclusion patterns must match real checkout paths and remain aligned with MANIFEST.in.
The test build commands target the interpreter running the test suite.
Release workflow tests classify every script-side guard by the irreversible action it must precede.
Pull requests use a template covering the change, motivation, and verification.
Weekly data updates resolve and download one explicit upstream release instead of racing separate “latest” requests.
Weekly data updates regenerate, open, merge, and publish through distinct data-release workflows.
update_data.sh uses non-interactive dataset flags and writes data-release notes automatically.
Changelog changes are filed as independently mergeable fragments and assembled during a release.
The build workflow exposes one stable ci-ok aggregate gate that fails when any required job is skipped, cancelled, or unsuccessful.
Release-branch pushes render commit-bound benchmark report artifacts automatically.
Published benchmark pages are rendered on named CI runners and distinguish full-suite reports from the tracked core subset.
Benchmark and memory commands assert the acceleration path they intend to measure.
Benchmark reports are generated from isolated plain-install environments rather than the contributor's optional dependency set.
CI benchmark comparisons report lookup throughput and memory comments use the median statistic.
The trend chart uses human-readable labels and timezone lookups per second rather than batch iterations per second.
CI tracks both batch lookup forms across random, unique-shortcut, and ambiguous-shortcut workloads.
Pull-request benchmark comments are replaced by posting the new commit-bound result before deleting the superseded comment.
Pull-request benchmark runs are path-filtered to changes that can affect tracked measurements.
Added a reusable, order-alternating candidate-comparison harness with unresolved outcomes when its estimators disagree.
Added per-query latency reporting alongside batch-oriented pytest-benchmark reports.
Added block-filtered point-in-polygon benchmarks for the kernel path used by real lookups.
Added a reproducible comparison suite against tzfpy that records the compared package version.
Added a memory harness that records allocation and resident-set metrics separately.
Added a query-stage profiling prototype and recorded its scope and limitations in contributor documentation. Solves issue #497.
Added a whole-query shortcut-resolution prototype whose correctness gate exercises alternative index resolutions.
The single-resolution prototype prices the serialized layout actually shipped and includes resolution 5.
scripts/tune_block_size.py validates candidate block sizes against rotated rings and the packaged layout.
Benchmark names and memory metric names are pinned so chart-history joins cannot drift silently.
Generated benchmark reports open with their measurement configuration and direct readers to methodology details.
Hand-written documentation links to generated reports rather than copying changing measurements.
The benchmark methodology documents paired candidate comparison and the asymmetric interpretation of stage shares.
The data-report generator returns RST and accepts an explicit output path instead of relying on redirected stdout.
The benchmark-report generator returns RST and accepts an explicit output path instead of relying on redirected stdout.
Parsing custom output writes its data report beside those binaries; only parsing the packaged directory updates the committed report.
The data report derives the H3 cell count from H3 rather than a finite table with a misleading fallback.
Shortcut-index report statistics are calculated by four typed, independently testable helpers.
The data report labels directly resolved cells as requiring no polygon tests rather than as storing zero polygons.
Report renderers choose labels and prose through named branches and shared parameter labels.
Coordinate resolution and ground-distance helpers derive documented precision from the dtype and scale.
Data-format documentation distinguishes source precision from storage capacity and explains accepted floating-point inputs.
Data-format documentation records why shortcut cells never make boundary geometry redundant.
The package comparison states when tzfpy is the more appropriate choice and links measurements to their source.
timezonefinder.flatbuf.schemas.__all__ contains only attributes the module defines.
Ruff enforces flake8-bugbear and RUF013 consistently in direct and pre-commit runs.
Warning calls identify their caller through stacklevel=2.
Ruff's prototype exclusions are declared once.
Ruff rule B023 is enforced for functions that close over loop variables.
Ruff rule B905 is enforced, with explicit non-strict zip calls where variable arity is intentional.
Mypy covers tests/ and the hook installs the stubs those annotations require.
Optional-dependency import failures explain the stale environment and recommend make install.
make force_update synchronizes all dependency groups.
make outdated correctly parses tree-formatted package names.
Pytest class-scoped fixtures use the classmethod form required by future pytest releases.
Cleanup exception tests are parametrized over the complete suppressed and warned exception sets.
Cleanup test doubles fail once so natural finalization cannot leak warnings into a later parametrized case.
CLI tests select application diagnostics by prefix instead of counting unrelated interpreter stderr lines.
Shared test helpers derive the repository root from scripts.configs so wheel installs do not resolve it inside site-packages.
One column per quarter.
The dataset version is now exposed at runtime. TimezoneFinder().data_version (and TimezoneFinderL().data_version) return the timezone-boundary-builder
New features:
The dataset version is now exposed at runtime. TimezoneFinder().data_version (and TimezoneFinderL().data_version) return the timezone-boundary-builder release the packaged data was built from, read from a data_version.txt stamp that scripts/file_converter.py writes into the data directory it generates and that ships in the wheel. Previously an installed timezonefinder could not state it at all: the release tag lived only in a repo-root file that is not packaged. Which release a parse is stamped with comes from the input's filename (combined-with-oceans-2026c.json, which update_data.sh now produces), or from scripts/file_converter.py --data-version for an input that cannot carry it; your own GeoJSON is stamped "unknown", and an unpacked release archive that lost its tag is refused rather than compiled into data that could never say where it came from. timezonefinder.__version__ is now exposed as well, read from the installed distribution metadata. Solves issue #498.
The command line script gained a --stdin streaming mode: it reads delimited rows from standard input and writes each back out with a timezone column appended, building the finder once instead of paying full initialisation per coordinate. Which columns hold the coordinates is read off the header by name, or stated with --lng-col/--lat-col, and never inferred from their position - a swapped pair is still a valid coordinate for any longitude between -90 and 90, so guessing would answer with a real but wrong timezone instead of failing. Every input row produces exactly one output row, and a row that cannot be used warns on stderr and makes the run exit non-zero rather than ending the stream. Whether the first row is a header is worked out from the row, or stated with --header/--no-header. New flags -d/--delimiter and --in-memory apply to the whole stream. See the usage documentation. Solves issue #504. Thanks to weed33834 for the PR #516.
Changed:
Polygon coordinates are now stored one axis at a time in the packaged coordinates.bin files - all x values followed by all y values per polygon, instead of interleaved. The point in polygon test scans a single axis per iteration, so contiguous per-axis blocks halve the cache lines it touches: ~1.6x faster on a median polygon and ~2.5x faster on the largest ones via the C extension, 14-25% faster via Numba. The bundled data was regenerated accordingly, and the layout is described in the data format documentation.
Every packaged FlatBuffers file now carries a file identifier and a layout version, and TimezoneFinder raises a ValueError naming the offending file when either does not match - previously such a directory was read without complaint and produced wrong timezones. For coordinates.bin the version records how the coordinates are encoded and which polygons the file holds. The hybrid shortcut binaries get an identifier that differs per zone id width, because the uint8 and uint16 schemas differ only in the width of a zone id and each parses cleanly as the other; the width is now read from the buffer instead of being guessed from the file name, so a renamed or mispaired shortcut file fails loudly rather than returning wrong zones. If you compile your own data and point bin_file_location at it, regenerate it once with scripts/file_converter.py, since the coordinate layout, the hole storage, the shortcut container and the file names all changed in this release. The markers track what a file holds rather than the package version, so this is not a per-release obligation. Solves issue #458.
The hybrid shortcut loader no longer keeps the entire shortcut binary in memory. The polygon id arrays it returns were zero-copy views onto the ~1.5 MB file buffer, so ~47 KB of live data pinned the whole thing for the lifetime of every TimezoneFinder / TimezoneFinderL instance. They are now disjoint read-only slices of a single compact array, cutting the shortcut mapping's footprint from ~7.4 MB to ~4.7 MB per instance, and every finder's resident set by ~2 MB, at unchanged initialisation time - which matters most for concurrent workloads, where the recommended one-instance-per-thread pattern multiplied the waste.
Holes that duplicate a timezone boundary polygon are no longer stored twice. Almost every hole is an enclave, cut into the surrounding zone with exactly the ring the upstream data also emits as the enclosed zone's own boundary polygon - the same geometry under two IDs. The packaged hole coordinate file now holds only the rings with no such twin (27 of 756 in the current data), and a new holes/poly_ref.npy records per hole which boundary polygon to read instead. Hole data drops from ~2.0 MiB to ~0.16 MiB, and in_memory=True saves the same amount of RAM, since those holes now resolve into the boundary arrays rather than materialising a second copy. Matching is exact - rings are compared as integer coordinates in a canonical form, with bounding boxes used only to narrow the search - so every timezone lookup returns what it did before. One visible consequence: get_geometry() may hand back a deduplicated hole ring starting at a different vertex or winding the other way than it used to, tracing the same closed path. The encoding is described in the data format documentation.
The timezone boundary data now ships as its own distribution, timezonefinder-data. pip install timezonefinder is unchanged - it is a hard dependency and is installed automatically - but the dataset can now be pinned on its own (pip install timezonefinder "timezonefinder-data==1.2026.3"), where previously holding a dataset meant pinning an old timezonefinder and forfeiting every code fix since. Every release used to carry the whole ~65 MB dataset in three platform wheels plus an sdist to distinguish a few kilobytes of compiled code, which had already exhausted the PyPI project storage quota once. A data update is consequently no longer a timezonefinder release at all: it publishes timezonefinder-data under its own tag namespace and is recorded in that package's README rather than here. Its version reads <format>.<year>.<letter> - 1.2026.3 is data format generation 1 built from timezone-boundary-builder 2026c - and timezonefinder requires timezonefinder-data>=…,<2: no ceiling on the data axis, so a dataset update needs no code release, and a hard one on the format axis, so code paired with data it cannot read fails when resolving rather than at the first lookup. DATA_LICENSE moves with the database it covers and now ships inside the data wheel, and a compiled data directory additionally carries a schemas/ copy of the FlatBuffers definitions its binaries were written by, so it can be read back without the package that wrote it. Solves the first part of issue #446.
The packaged FlatBuffers binaries are now named .bin rather than .fbs: boundaries/coordinates.bin, holes/coordinates.bin and hybrid_shortcuts_uint16.bin. .fbs is the FlatBuffers schema extension, and the data directory now ships actual schemas next to the buffers, so one extension was naming two unrelated kinds of file. Each buffer already states what it is through the file identifier in its first bytes, which is what a rename or a mispaired copy cannot forge - the name never carried that meaning. The bytes are unchanged.
Bug fixes:
Fixed a BufferError: cannot close exported pointers exist raised during resource cleanup in file mode (in_memory=False). A coordinate array obtained from coords_of() is a zero-copy view onto the memory-mapped file, and mmap.close() refuses to unmap while one is alive, so an array outliving its TimezoneFinder raised on cleanup. The mapping now stays valid instead of leaving the views dangling, and FileCoordAccessor.cleanup() releases its own references so the deferred close happens as soon as the last view is dropped. The accessor must not be used after cleanup().
Documentation:
The memory footprint of every finder configuration is now measured and published in a new memory report, separating what a configuration allocates (tracemalloc) from what it makes resident (RSS, which additionally counts memory-mapped pages). The distinction is the point: the default mode maps the coordinate data instead of reading it, so it allocates an order of magnitude less than the in-memory mode, and only the pages a lookup actually touches become resident. This replaces documentation claiming a 40MB process ceiling and a 41MB data directory, both long out of date.
Restructured the two entry points a reader actually arrives at - README.rst and the documentation landing page - so both state what the package is and how it works instead of only what it is called. The README opens with the project banner and a one-sentence statement of what the package is for, then the badges, then the quick guide - and adds three short sections that were missing entirely: How it works (the lookup pipeline and the no-simplification trade-off), Performance (a concrete throughput figure with its configuration named, the three point-in-polygon backends and the pure-Python fallback), and Engineering notes linking the architecture, data format and benchmarking methodology pages. The maintainers-wanted notice moves from the first heading after the intro into a new Contributing section at the bottom, which also links CONTRIBUTING.md for the first time. The badge block is corrected along the way: the code style: black badge named a formatter this project has never used and is replaced by ruff, and a supported-Python-versions badge was added. The banner is referenced by absolute URL, since PyPI serves the long description without the repository and a docs/… path renders as a broken image there. The landing page gains the same How it works summary, the no-simplification trade-off and the ocean-zone consequence for timezone_at(), and its flat seventeen-entry table of contents is grouped into Using it, Design, Performance and Project, so the sidebar says what kind of project this is rather than listing pages in the order they were written.
Rewrote the package comparison page. It now states its position in prose before the first table - border correctness is what this package optimises for, speed is the constraint that work happens under - and says plainly when tzfpy is the better choice. Every quantitative cell names what it measures and links its source, and the speed row is deliberately qualitative on both sides, with a note explaining that the two packages have never been benchmarked under one harness. The decision table drops the rows on which the two packages do not differ.
Two new documentation pages: Architecture describes the lookup pipeline, the three point-in-polygon backends and the memory modes, and states the ceilings this package deliberately does not exceed - unsimplified geometry, ~1 cm coordinate resolution, no general-purpose spatial code. It also documents how the package is built and shipped, which was previously described nowhere outside the workflow YAML: why one abi3 wheel per target replaces one wheel per Python version and what abi3audit is guarding, why three libc targets are built, why the end-to-end job installs the built wheel and asserts the C extension loaded rather than merely importing the package, and why a tag pushed from outside master aborts the release. The testing section gained the property-based suite and the reason the tox matrix is a matrix - the acceleration paths are bound at import time, so a passing run describes one configuration only. Both sections are linked from the README's Engineering notes. Benchmarking Methodology documents how the published numbers are produced and what they can and cannot tell you: ubuntu-latest pins the runner image and not the CPU, which is why a pull request is measured against its own merge base on the same runner and why every alert threshold is derived from measured noise. It was previously addressed only to contributors, in the second half of CONTRIBUTING.md, which now keeps the operational instructions and links to it.
The H3 resolution choice in the data format documentation is no longer asserted to "offer a good balance" but reports the study behind it (prototypes/single_resolution_bench.py): resolution 3 keeps the hybrid index at a small fraction of the packaged polygon data, while resolution 4 would exceed 10 % of it for gains that do not justify the increase.
The hand-written documentation no longer restates exact figures that belong to the generated pages - dataset vertex, polygon and hole counts, index and distribution sizes, memory footprints, lookup throughput. Those change with every data update and with code that shifts a footprint, which silently left the copies wrong: the memory figures had already gone stale in four places. The prose now states the magnitude that survives a data update and links the data report or the relevant benchmark report, which are regenerated from the packaged data and are always current.
The three weakest hand-written documentation pages no longer answer a question by pointing at a file the reader has to open. The performance page now opens with the four benchmark reports and the trend chart instead of a bullet list of adjectives about the binary format, and its C extension and Numba sections are cut to what a user does - which call reports the active backend - with the explanation left to the architecture page that already carried a more precise version of it. Getting started lists the four runtime dependencies and what each is for, where it previously said to consult pyproject.toml, which remains linked as the authoritative source for version ranges. The use case pages carry runnable snippets for building an aware datetime and reading a UTC offset, with the examples/ scripts as the follow-up rather than the whole answer; the snippets use the standard library's zoneinfo, so neither needs an optional dependency.
The shortcut entry distributions in the data report no longer report three quarters of all H3 cells as holding 0 polygons, which is impossible for data whose ocean zones cover the globe. Those cells are covered by a single timezone and store its id directly, so a lookup there needs no point-in-polygon test at all - the column is now Polygons to test and the row reads none (unique zone). The tables are introduced by a sentence on what they measure, including why no cell ever needs exactly one test.
The usage examples in README.rst and the usage documentation now show the result the packaged data actually returns. Every snippet queries the same Berlin coordinates and annotated the answer as 'Europe/Paris', which is the value from the reduced timezones-now dataset, where Europe/Berlin is merged into Europe/Paris - not from the full dataset the package ships by default. All eleven annotations now read 'Europe/Berlin', verified against the packaged data for each of timezone_at(), timezone_at_land(), certain_timezone_at(), unique_timezone_at() and TimezoneFinderL, and the get_geometry() call in the opening example asks for that same zone instead of a different one. tests/test_documented_contracts.py now re-runs each of those documented lookups, so a data update that moves the example coordinate's zone fails there rather than leaving every snippet on both pages quietly wrong again.
Internal:
The release pipeline refuses to publish timezonefinder unless a compatible timezonefinder-data already exists on PyPI. The two distributions release independently, and on a data format change the order is fixed - data first, then the code requiring it - because a code wheel whose declared data version does not exist yet is uninstallable for everyone until it does, and the version number cannot be reused to fix it. The check reads the requirement out of the built wheel rather than out of pyproject.toml, and asks the index the same question a user's resolver will, so a yanked release does not count as one that satisfies it. It runs before the GitHub Release, which is the first step of the release that cannot be taken back.
Pull requests are opened against a template (.github/pull_request_template.md) prompting for the change, its motivation and the checks that were run.
update_data.sh resolves the timezone-boundary-builder release tag before downloading and fetches that release's asset, instead of fetching releases/latest/download/ and separately asking the API what latest was - two independent questions that a release landing between them answered differently, attributing one release's data to the other. The tag now names the downloaded archive and the GeoJSON as well, so a leftover file from another release or another dataset variant cannot satisfy the "already downloaded" checks and be parsed in place of what was asked for.
Names and docstrings now describe what the code does. TimezoneFinder.timezone_at documents the optimisation it actually performs: once no other zone can be matched the last remaining zone is returned without a point in polygon test, which is always correct against the packaged data - the ocean zones cover the globe, so every point lies within one of the candidate polygons - but not against custom data that leaves areas uncovered, where a point inside none of the candidates is still attributed to that zone and certain_timezone_at is the method that tests every candidate. Three tests were named after something other than what they do: test_rectify_coords_valid/_invalid were named for a rectify_coords that exists nowhere in the package and both call validate_coordinates, and the first was subsumed entirely by test_validate_coordinates_accepts_finite_values, which covers all four of its distinct corners and additionally asserts the return value where the older test asserted only "does not raise"; and test_single_element_arrays_should_not_occur asserted that they do occur (assert single_element_count == 2) under a triple-quoted string placed after the first statement, making it a discarded expression rather than a docstring - so it reached neither --collect-only nor a failure report, which is where the contradicting name was the only thing a reader saw. A stale comment duplicated across the last two lines of tests/main_test.py, reading as a to-do for something TestTimezonefinderClassTestMEM already does, is gone.
Added DATA_VERSION file tracking which timezone-boundary-builder release the packaged data was generated from, written automatically by the data update script after a successful parse. Thanks to Lucas Hemkemeier for the PR #429.
The packaged data now updates itself: a weekly workflow compares DATA_VERSION against the latest timezone-boundary-builder release, regenerates the data and opens a ready-to-review update PR, which is merged and released automatically once its CI passes - the version tag is pushed with a GitHub App token, since the default one would not trigger the release pipeline. The tag lives in its own data-v* namespace, which the code release pipeline excludes at its trigger and again on the job that creates the GitHub Release, and the data stream publishes by PyPI Trusted Publishing from its own deployment environment rather than with a shared token. It refuses to release when the squash it produced did not land on the master it checked, so the tag names a tree that was actually built. Failed CI takes the same manual-attention path and falls back to the previous notification issue. Each cause labels the PR automation-failed and leaves one comment naming that cause and linking the run, deduplicated per cause so re-running CI neither repeats a notice nor hides a second one; a failure past the merge is a cause of its own, since that leaves master carrying the update with no tag pushed and only a hand-pushed tag still releases it. The manual release path drops the stop condition it carried for an out-of-order CHANGELOG.rst: the automation can no longer produce one, and the test suite asserts the committed file's section order if anything else does (issues #273, #167 and #510). Thanks to Lucas Hemkemeier for the PRs #434 and #436, and to Nice6042 for the PR #518.
update_data.sh (renamed from parse_data.sh) is CI-ready: interactive prompts replaced by flags (--dataset=full|same-since-now, --with-oceans, --rm-tmp), the release note for a data update written automatically into the data package's README, no redundant tox run, and a make reports at the end so the benchmark and data reports cannot go stale relative to the data an update PR ships. A standalone make parse/make testparse still needs a manual make reports (issues #167 and #510). Thanks to Lucas Hemkemeier for the PRs #432 and #434.
Added property-based tests (hypothesis) for coordinate validation (solves issue #143). Thanks to Lu Yicheng for the PRs #431 and #433.
Replaced the hand-rolled timeit timing in scripts/check_speed_*.py with pytest-benchmark suites under benchmarks/, excluded from make test/make testall via testpaths. Both they and the memory harness run over deterministic committed fixtures (tests/fixtures/benchmarks/), so two runs of the same commit execute the exact same workload; the loader rejects fixtures that no longer match the checkout. Measurement and rendering are decoupled, so docs/benchmark_results_*.rst can be regenerated from a stored JSON without re-measuring. Run via make speedtest, make benchmarks, make memory or make reports.
Memory is measured by its own harness (scripts/measure_memory.py, make memory) rather than by pytest-benchmark, which times code and would have its timings distorted by allocation tracking. It emits pytest-benchmark-shaped JSON, so the existing normalisation, noise and comparison tooling works on it unchanged given a --metric. tests/test_memory_footprint.py fails if a mode's allocation leaves its order of magnitude - the regression that would make in_memory=False stop being the low-memory option.
Added continuous benchmarking on CI (solves issue #150), deliberately kept out of the release pipeline in build.yml: the tracked core subset and the memory harness run on every pull request and every push to master, publishing trend charts to gh-pages and posting a same-runner base/head comparison on the pull request. The comparison reports added or removed benchmark IDs without trying to ratio unmatched measurements, which lets the trusted default-branch consumer remain compatible while the suite evolves. A pull request is measured against its own merge base in the same job rather than against a stored baseline, because runs-on: ubuntu-latest pins the runner image and not the CPU. The measurement design, the tracked estimator and every alert threshold are documented in the new benchmarking methodology page. The measuring job holds no write permissions and no secrets, so branch and fork pull requests behave identically; the comment is posted by a separate, privileged workflow via workflow_run.
Guarded the benchmark plumbing against silent drift: tests/test_benchmark_names.py and tests/test_memory_metric_names.py pin the node ids and metric names that join a measurement to its chart history, so a rename fails loudly instead of starting an empty chart beside the orphaned old one; tests/test_benchmark_workflows.py asserts that the constants duplicated across the two workflows agree, where a one-sided edit previously had no failure mode at all, and that the cross-machine trend chart cannot creep back into the pull request comparison; and every generated report page states the inputs it describes - docs/benchmark_results_*.rst the fixture and timezone data versions they were measured against, docs/data_report.rst the timezone data version its figures were derived from. Both stamps are covered by tests: one renders each report and fails if a renderer stops emitting it, another checks the committed pages against the current fixture metadata and DATA_VERSION, so regenerating fixtures or updating the data without re-rendering fails loudly instead of leaving a page whose numbers are all plausible and all stale.
Every generator now emits output that is already pre-commit-clean, so regenerating and diffing compares like with like: write_json sorts keys the way pretty-format-json does, and neither scripts/reporting.py nor BenchmarkReporter emits trailing whitespace on empty cells or a trailing blank line. Previously every make parse/make reports left its outputs looking modified until the hooks had run, which masked whether a regeneration had actually changed anything.
Every generated benchmark report now opens with its headline figure and the configuration behind it, above the tables: how long a lookup takes and how many per second, the per-check cost across polygon sizes, construction time, footprint per mode - all derived from the same parsed JSON as the tables, never hardcoded. The banner beneath states which acceleration path and platform produced the numbers, and says whether that is the configuration CI tracks: the committed reports are rendered from a developer machine with Numba enabled, while CI measures the C extension without Numba, so their figures were never comparable to the trend chart and now say so.
make flatbuf no longer overwrites hand-maintained __init__.py files. flatc derives its output path from the schema namespace and writes an empty __init__.py at every level of it, so generating in place wiped the __all__ in timezonefinder/__init__.py - the whole public API. The target now generates into a scratch tree, copies back only the generated packages, and runs the formatters on the result so a regeneration diff shows the codegen change rather than formatting churn.
Mypy now type-checks the whole package except the flatc-generated bindings. ignore_errors previously covered roughly 800 lines of hand-written code as well, where a blatantly wrong return type still reported "Success"; they all pass once the exemption is lifted, bar two genuine findings now fixed. tests/test_mypy_config.py keeps the list restricted to generated code, so silencing a module is a reviewed decision rather than a one-line edit.
The hybrid shortcut reader and writer now select their FlatBuffers schema from a single registry (SHORTCUT_SCHEMAS in timezonefinder/flatbuf/io/hybrid_shortcuts.py) instead of dispatching on the zone id width in three places, each keyed differently. One ShortcutSchema per width owns the width, the file name, the uintN marker and the maximum zone id, which were previously written down across five places with nothing tying them together. Verified behaviour-preserving down to the bytes: re-writing the shipped shortcut binary produces a byte-identical file.
Each distribution's build is now asserted to contain exactly what it should. The data wheel's payload is compared against the committed dataset as a set, in both directions: a missing binary fails on first use and gets reported, but an extra one ships silently - setuptools copies package data into build/lib and never prunes it, so a file renamed in the source tree keeps being zipped into every later wheel built from that checkout, which is how a 63 MB coordinates.fbs was still shipping next to the coordinates.bin that replaced it and doubling the wheel whose size is the reason the distribution was split out. The wheel builders clear that directory first, so a local build matches the fresh checkout CI builds from, and the code sdist's checks cover its grafted test fixtures again.
The packaged data is additionally held to a floor on how much hole deduplication achieves - the test suite fails if fewer than 90% of its holes match a boundary polygon (96.4% currently), because a future upstream release that stopped emitting enclaves as shared rings would still compile and still return correct timezones, just with the shipped data quietly re-inflated. The floor applies to that dataset and nothing else: compiling your own GeoJSON with scripts/file_converter.py is a supported use case, holes that are ordinary interior rings rather than enclaves are stored inline and answer correctly, and the converter only reports the ratio rather than refusing to compile. prototypes/hole_boundary_redundancy.py is the study behind the threshold: it reads the upstream GeoJSON, so re-running it against a new release re-verifies the assumption rather than restating it. prototypes/hole_removal_impact.py is the study behind keeping the unmatched holes stored inline rather than dropping them, which is the obvious next step and does not work: dropping holes and re-running the lookups changes answers, wrongly, because being covered by another zone only puts that zone among the shortcut candidates and says nothing about it being tested first (issue #513).
Removed constructs that provably did nothing, and gave two vacuous tests real assertions. Most consequentially, four __slots__ entries were declared but assigned by nothing, which silently re-permitted the very attributes __slots__ is there to forbid - assigning those names now raises AttributeError, and test_declared_slots_are_assigned keeps the list honest.
get_corrected_hex_boundaries exists once again. An earlier refactor left two verbatim copies of the antimeridian and pole clipping rules with nothing keeping them in sync; the copy without callers is deleted, and the survivor is now covered by tests/hex_utils_test.py - it previously had no direct tests at all. scripts/configs.py no longer declares MAX_LAT/MAX_LNG as a second pair of names for timezonefinder.configs's constants.
prototypes/ has a README.md saying what the three scripts there are: exploratory studies behind committed design decisions, run by hand, outside the package and the test suite. One of them is the measurement that chose H3 resolution 3 - the central algorithmic parameter of the package, already cited from the data format page - and another is the evidence for not building a hierarchical index. MANIFEST.in now excludes the whole directory from the source distribution rather than only its *.py files.
plans/ is git-ignored alongside tmp/ and .venv/: implementation plans written while working on a change are local scratch, and leaving the directory untracked-but-unignored made it noise in every git status and a candidate for an over-broad git add.
Failing paths now report the input that failed. tests/auxiliaries.py's run_command assembled the child's stdout and stderr into a message and then raised a fresh CalledProcessError that never used it, with from None discarding the original too, so a packaging failure under make testint reported an exit code and nothing about the cause; it now echoes the captured streams and re-raises the original exception with its traceback intact. scripts/reporting.py passes the coordinate file paths into get_polygon_collection, whose optional file_path exists precisely so an incompatible-layout ValueError can say which of the two files was stale - make reports against an outdated data directory previously could not. Boundaries.overlaps names the type it rejected instead of raising a bare TypeError, and the RuntimeError for missing original_polygons names the polygon and resolution it was computing. The two re-raises ruff flags under B904 now say from None explicitly, so a deliberately dropped exception chain is distinguishable from a forgotten one, and timezonefinder/command_line.py drops FileNotFoundError from an except tuple that already caught its base class OSError. tests/test_error_diagnostics.py pins what each of these messages must contain.
The command line interface no longer routes its own output through a temporary file. main redirected stdout to a mkstemp file for the duration of the lookup and then, in verbose mode, reopened it to read back a string it still held in a local variable - nothing inside the redirected block ever wrote to stdout, since the lookup functions return their result rather than printing it. The context manager, the read-back, its warning path and the file cleanup are gone, and the lookup function is now resolved once per invocation instead of twice, so -f 3/-f 4 under -v no longer construct a second TimezoneFinderL and reload its shortcut data just to read a function name. Output is unchanged character for character, across every function id in both modes. tests/cli_test.py gains the coverage that makes that checkable - verbose mode, the empty line printed when no timezone is found, and the rejected function id had none - and asserts the printed name verbatim instead of passing it through rstrip("\n\x1b[0m"), which strips a set of characters rather than a suffix and so truncates 12 of the packaged zone names (Europe/Amsterdam -> Europe/Amsterda).
Docstrings now describe the code that exists. Six documented something the implementation contradicts: AbstractTimezoneFinder.__init__ called in_memory inert and "kept for API compatibility" when it is what selects memory-mapped against in-memory coordinate access - the claim help(TimezoneFinder) surfaces, and the opposite of what the usage docs say; both get_geometry docstrings pointed at a timezone_names.json that does not exist under that name; read_zone_names promised an empty list where it raises FileNotFoundError, and illustrated itself with a hardcoded zone count that the packaged data had since outgrown; and zone_id_of / zone_name_from_id each advertised an exception type they convert away, sending callers to write handlers that can never fire. Five further :param:/Args: entries in scripts/ and tests/ documented arguments that were removed along with the parallel shortcut compilation they belonged to. tests/test_documented_contracts.py pins the exception types and the coordinate access mode, so those promises now rest on something besides prose.
The test and benchmark suites no longer contain checks that cannot fail. Eighteen calls sat inside four shared pytest.raises blocks in tests/main_test.py, and execution leaves such a block at the first statement to raise - so one out-of-range coordinate, one positional call shape and one rejected get_geometry input were verified while the remaining fifteen were unreachable. Each is a test case of its own now: every coordinate just outside the WGS84 range, every positional call shape of every keyword-only lookup method, and the unknown-zone-name, past-the-end and negative zone id rejections of get_geometry. The __del__ cleanup test binds its exception per iteration rather than closing over the loop variable, which decided what a garbage-collected instance would raise long after the loop had moved on. On the benchmark side, pip_inputs_by_stratum validated only the strata the fixture happened to contain, so one missing from it altogether passed and surfaced later as a bare KeyError inside a benchmark, and the points and their labels were paired from two files with a non-strict zip that truncates silently. That grouping now lives in tests/auxiliaries.py as group_pip_inputs_by_stratum, checks against the declared PIP_STRATA - which the generator no longer keeps a second copy of - and has tests for each way the two fixture files can disagree.
Both point-in-polygon acceleration paths are now covered by a local test run, whichever one the environment happens to bind. The implementation is selected at import time and Numba wins whenever it is importable - which the documented setup (uv sync --all-groups) makes it - so the C extension was reached only by direct-kernel tests on hand-built arrays, and everything about how real polygon buffers arrive at it, including the read-only memory-mapped views, was first exercised in CI's non-numba tox environments: the configuration a plain pip install timezonefinder produces. tests/test_acceleration_paths.py now rebinds utils.inside_polygon and drives the full lookup stack through both implementations, asserting that they agree across the real boundary data, that the C path returns the known-correct answers, and that the point-in-polygon stage was reached at all rather than short-circuited by the shortcut layer (issue #482).
The packaging guard in tests/test_package_contents.py no longer names files that do not exist. It asserts that nothing in the built sdist and wheel matches a list of unwanted paths, which passes just as readily when a pattern matches nothing at all: .github lacked the trailing slash that directory patterns need, Agents.* stopped matching when the file was renamed to AGENTS.md, and readthedocs.yaml never matched readthedocs.yml - so the CI configuration and both of those files were unguarded while the suite stayed green. The patterns are corrected, the provider stubs, contributing/, .agents/, .claude/ and .cursor/ are covered to match what MANIFEST.in excludes, and test_every_unwanted_pattern_matches_a_project_file now fails on any hand-written pattern that matches no path in the checkout, so the next rename cannot silently disarm one. It carries the unit marker rather than the module's former blanket integration mark, since it needs no build: a mistyped pattern surfaces in make test. .gitignore re-include lines (!…) are also no longer read as exclusions, which had produced one more parametrised case that could never fail. The converse direction is checked too: test_every_manifest_exclusion_is_guarded parses the exclude/recursive-exclude/prune/global-exclude directives out of MANIFEST.in and fails when one of them keeps a path out of the build that no pattern here names - previously such a line was enforced by the build and verified by nothing, so deleting it would have shipped the file with the suite still green. The two lists are hand-maintained statements of one intent and had drifted before, in both directions. The architecture page describes the guard from both sides: among the tests that exist to give an invariant a failure mode, and under How it ships as the check on what the built artifacts actually contain.
The distributions built by the test suite are now built for the interpreter running it. uv build was invoked without --python, so it targeted the newest interpreter on the machine, while tests/test_integration.py creates its throwaway venv from sys.executable: on a checkout whose .venv is older than the newest installed Python, make testint produced a cp314 wheel and failed with pip's "not a supported wheel on this platform". Every tox environment offers a single interpreter, so the two agreed by accident in CI and the mismatch only ever hit developer machines, where the workaround was to pin UV_PYTHON. test_build_commands_pin_the_running_interpreter keeps the pin in place; it needs no build, so it fails in make test rather than waiting on a CI environment that cannot reproduce the mismatch.
Two tests no longer leak numpy's global error state into whatever pytest collects next. np.seterr and the warning filters are process-global, and test_overflow (tests/main_test.py) plus test_inside_polygon (tests/utils_test.py, six parametrisations) each set them and never restored them - so every later test in the same process ran with under promoted from ignore to warn, and which of the two modules pytest collected first decided the state the other ran under. The filters were undone only incidentally, by pytest's per-test catch_warnings(), not by the tests themselves. benchmarks/conftest.py already had the correct pattern; it now lives in tests/auxiliaries.py as the strict_numpy_errors context manager plus a thin strict_numpy_warnings fixture, re-exported through the conftest of each suite, and both call sites request it. The context manager form is what makes the restore directly testable - a leaked global otherwise surfaces only as an unrelated later failure that depends on collection order, which is the hardest kind to attribute.
The zone id invariants in scripts/timezone_data.py are each enforced in exactly one place, and now have tests. ZoneCollection.validate_structure and zone_positions each walked poly_zone_ids element by element checking it was non-decreasing and each raised the same message built from its own locals; the scan moves into one _validate_non_decreasing helper and zone_positions drops its copy, which could only ever have fired if a caller mutated the array in place - the validator runs at construction and nothing writes to it afterwards. A if min_zone_id < 0 branch is deleted as unreachable: the same method rejects any non-unsigned dtype a dozen lines earlier, so it read as the guard against negative zone ids while being incapable of firing. The class had no tests at all, so what it actually promises - the unsigned-dtype rejection that makes a negative id unrepresentable, the ordering and maximum-id rules, and the shape zone_positions returns - is now pinned by tests/timezone_data_test.py.
The seven out-of-range coordinates - one representable step outside the valid WGS84 range, per axis and at every corner - are declared once in tests/locations.py instead of verbatim in both tests/main_test.py and tests/utils_test.py, where only one copy carried the comment explaining what makes them interesting and adding a corner to it left the other testing a smaller set.
The shortcut compilation chain in scripts/shortcuts.py is annotated for what it is actually passed. Both annotations were the wrong way round: check_shortcut_sorting declared np.ndarray and only ever receives the list[int] that optimise_shortcut_ordering returns, and it hands the np.ndarray it derives to has_coherent_sequences(lst: list[int]). Widened rather than swapped, since tests/shortcut_test.py calls the latter with real lists.
The supported Python versions are declared in five places that cannot read each other - requires-python and one classifier per minor version in pyproject.toml, the py{...} factors of tox.ini's envlist, the test matrix and CIBW_BUILD_VERSIONS in build.yml, and py_limited_api in setup.py - and two "must match" comments said so while nothing enforced them. tests/test_python_version_support.py fails when they drift, in either of the two directions that fail silently: a classifier added without a matrix entry ships a version the package claims to support and CI never runs, and a requires-python raised without moving the abi3 base builds wheels tagged for an interpreter that is no longer supported. Each assertion was checked against the specific one-sided edit it targets, and both comments now name the test.
The data report generator states figures it derives rather than ones it restates, and its annotations describe what it returns. calculate_shortcut_index_stats took the number of H3 cells existing at the shortcut resolution from a ladder of literals covering resolutions 0 to 4 and fell through, for anything else, to the number of cells actually stored - which reports coverage of exactly 100 % instead of failing - behind an except ImportError that cannot fire, since h3 is a runtime dependency rather than an optional one. It asks h3.get_num_cells, which returns precisely the numbers that were tabulated. Running mypy over scripts/reporting.py, which the pre-commit hook excludes, found seventeen further disagreements between the module and its own signatures: the statistics bag was typed as holding scalars while returning two distributions, load_binary_data's nine-key result was a bare dict indexed by string literal, the table renderer declared string rows while stringifying whatever it is handed, main was annotated None while returning exit codes to exit(), and print_polygon_distribution_table documented a return value it never produced while its one caller discarded it. The two dict results are now TypedDicts in scripts/configs.py, carrying tests that assert their keys against what is really returned, since CI cannot type-check scripts/. The polygon count that labels a distribution row is no longer formatted into that label and parsed back out of it to key the example lookup. docs/data_report.rst and the benchmark reports regenerate byte-identically throughout.
Removed five definitions nothing referenced - three JSON/pickle helpers in scripts/utils.py and the import pickle they kept alive, the i8 dtype shim in timezonefinder/_numba_replacements.py that the no-numba fallback never imports, and a test helper self-documented as kept for future reference - and a guard in scripts/hex_utils.py that could not fire. Hex.poly_candidates re-read its cache after initialising it and returned an empty set if it were still unset, which no path through _init_candidates leaves it: an empty set there means "no candidate polygons", so a converter bug would have surfaced as silently missing shortcuts rather than as a failure. The property had no direct test, being reached only through shortcut generation, and now has one. _memory_mode_label looks its two labels up in PARAM_LABELS instead of spelling them out, so renaming the display vocabulary can no longer leave the comparison bullets and the tables above them disagreeing.
make parse and make testparse run again. Both invoked scripts/file_converter.py by path, which puts scripts/ on sys.path[0] instead of the repository root, so the converter's own from scripts.timezone_data import ... raised ModuleNotFoundError before any work started - a total failure that CI never sees, since it runs neither target. make testparse is the only cheap end-to-end exercise of the converter (update_data.sh needs a ~55 MB download), and nothing under tests/ covers parse_data(), so while it was broken the converter had no smoke test at all. The invocation documented in the usage docs had the same defect and is now the python -m scripts.file_converter form that update_data.sh already used; tests/test_script_invocations.py fails if a by-path invocation returns. Note that parse_data() writes its report to the checkout's committed docs/data_report.rst whatever -out it is given, so make testparse leaves that file describing the three-zone fixture - the target now says so.
scripts/ is type-checked by the mypy pre-commit hook instead of being excluded from it. The directory holds the data converter and the benchmark tooling - most of the repository's non-library Python - and with nothing running mypy over it the annotations had drifted to fifteen errors: two # type: ignore codes mypy no longer emits, so the ignore silenced nothing; two implicit Optional defaults that no_implicit_optional = true was already configured to reject; a dict annotated with a narrower value type than it is assigned; a bucket key and four bounding-box lists annotated int while Boundaries declares float; and two missing variable annotations. All fixed as annotations, with no runtime change. Two of the four errors mypy reported in tests/auxiliaries.py, which it reaches by following imports out of scripts/, are fixed alongside. test_scripts_are_type_checked_by_the_hook guards the exclude, which is a quieter way to stop type-checking a directory than the ignore_errors list the neighbouring tests already cover: it takes no override entry and reports nothing.
The eight __del__ cleanup tests that differed only in which exception cleanup() raised, and whether zero or one ResourceWarning was expected, are two parametrized tests over the suppressed and warned exception tuples. Each previously repeated the same subclass, the same catch_warnings block and the same filter, so adding a ninth exception to __del__'s suppression list meant copying the block a ninth time and a copy asserting the wrong count would be invisible. Coverage rises rather than falls: the hand-rolled loop asserting that __del__ never raises to user code now runs over all six exception types instead of four.
Three leftovers in the converter that read as bugs are gone: has_coherent_sequences built an iterator solely to take its first element and then looped from the start anyway (correct, but it reads as an off-by-one), compile_bboxes unpacked a pair and immediately reassigned half of it, and process_single_hex returned the hex_id it was handed so its only caller reassigned the loop variable to itself. Two shadowed builtins (dir as a loop variable, id as a parameter) are renamed and three bare generator signatures annotated. The benchmark renderer classifies its "other" group by name suffix, as the two lines above it do, rather than by deep-equality scan over lists of dicts; and the check-manifest ignore list drops two entries naming files that do not exist (CONTRIBUTING.rst, publish.py). Every converter change was verified by parsing tests/test_input.json before and after and comparing the outputs byte for byte.
* updated the data to 2026c __
updated the data to 2026c
added manylinux_2_28_x86_64 wheel to releases, fixing the fallback to version 6.0.1 when pip resolves with --platform manylinux_2_28_x86_64 (Python 3.
added manylinux_2_28_x86_64 wheel to releases, fixing the fallback to version 6.0.1 when pip resolves with --platform manylinux_2_28_x86_64 (Python 3.14 + numpy 2.4). . Thanks to theirix for the PR #420
fixed deprecated patterns: updated tempfile API usage to modern context managers, fixed import ordering (stdlib first)
updated the data to 2026b
added examples and documentation for using parallel processing with the timezonefinder libary.
Internal:
reduced code duplication in coordinate validators: extracted common validation logic into a reusable _validate_coordinate() helper function
improved error handling and warning emission during __del__ resource cleanup
decomposed monolithic main() function into focused, independently testable components: _parse_arguments(), _lookup_timezone(), and _print_lookup_details()
reduced cyclomatic complexity and improved separation of concerns
migrated from typing module imports to collections.abc for Iterable and Callable
added Self type annotation for context manager protocol
replaced conditional dispatches with match/case statements for improved clarity and maintainability
using python 3.10+ type hints. Thanks to Marco Barbosa
added 8 comprehensive thread safety tests for concurrent singleton initialization
added 37 coordinate validation tests covering edge cases (NaN, Inf, boundary values)
improved exception handling: replaced bare except clauses with specific exception types (FileNotFoundError, OSError, IOError), added proper exception chaining via from e
enhanced type hints: added complete type annotations to public APIs, resolved type checking issues with mypy
enriched documentation: added comprehensive module and function docstrings with parameter descriptions, return types, error documentation, and usage examples
explicit API exports: added __all__ declarations to utils.py, zone_names.py, global_functions.py, and configs.py for clearer public API surface
improved error messages: replaced vague errors with specific context including valid ranges, expected values, and data locations
fixed deprecated patterns: updated tempfile API usage to modern context managers, fixed import ordering (stdlib first)
enhanced validation: added type checking for string inputs, better coordinate validation with clear error messages
* updated the data to 2026a __
updated the data to 2026a
require numpy >=2 following the official NumPy Deprecation Policy __
updated the data to 2025c
require numpy >=2 following the official NumPy Deprecation Policy
dropped official support for Python 3.9 and 3.10, due to NumPy dropping support for these versions.
Internal:
Introduced slow test marker for computationally expensive tests to improve CI performance and local development workflow. Updated CI configuration, tox environments, Makefile targets, and documentation accordingly. Thanks to Chase Horton for the PR.
enabled Numba tests for Python 3.13 and 3.14.
Reverted to the full timezone dataset: Starting from this release, timezonefinder uses the full original timezones-with-oceans dataset instead of the
Reverted to the full timezone dataset: Starting from this release, timezonefinder uses the full original timezones-with-oceans dataset instead of the reduced timezones-now dataset. This restores access to all >440 original timezone names, providing full localization capabilities and historical timezone accuracy. The reduced dataset (with ~90 timezones) is still available via the parse_data.sh script for users who prefer the smaller memory footprint. Due to the discussion in GitHub Issue #363
Improved error handling for resource cleanup. Thanks to Dave Tapley for the PR #375.
Bug fixed where on termination we may hit an exception attempting to close resources in FileCoordAccessor. Thanks to David Park for the PR #377.
Made CFFI extension builds fallible, allowing the build process to continue even if C extension compilation fails. Thanks to theirix for the PR #369.
Added Python 3.14 to the supported test matrix (tox + GitHub Actions).
add the support of using the TimeZonefinder class instances as context managers. added a basic usage examples
add the support of using the TimeZonefinder class instances as context managers. added a basic usage examples
note that the performance of certain_timezone_at() degraded drastically, since now many more polygons will be checked with an expensive point-in-polygon algorithm. consider using timezone_at() or timezone_at_land() instead.
introduced hybrid shortcut index structure that combines the functionality of separate shortcuts and unique shortcuts into a single optimized data structure, improving performance and reducing memory usage
zone id storage now defaults to uint8 and can be overridden via --zone-id-dtype/TIMEZONEFINDER_ZONE_ID_DTYPE when recompiling binaries
relax cffi upper bound to allow the 2.x series so downstream packages pinning cffi>=2.0 resolve cleanly
scripts/reporting.py can now be executed as a standalone script to generate data reports from binary files independent from file_converter.py
the check_speed_*.py scripts now generates a detailed performance reports in reStructuredText format automatically included into documentation
Internal:
using abi3 (aka Python limited API) wheels to avoid a combinatory explosion with Python version. It allows the use of a single Python 3.9 base and building future-proof wheels. Thanks to theirix
using pydantic to validating and parsing the GeoJSON dataset. Thanks to ARYAN RAJ for the PR.
refactored file_converter.py to improve code quality. Thanks to Pratyush Kumar for the PR.
consolidated shortcut data structures: replaced shortcuts.fbs file with hybrid_shortcuts_uint8.fbs (or hybrid_shortcuts_uint16.fbs) file that stores both polygon lists and direct zone IDs using the minimal dtype for zone IDs.
starting from this release, timezonefinder uses the reduced timezones-now dataset version (cf. GitHub Discussion __ )
starting from this release, timezonefinder uses the reduced timezones-now dataset version (cf. GitHub Discussion )
in this dataset version, all timezones which agree on timekeeping methods as of the release date of the dataset, are merged into one zone (cf. Dataset Documentation ). This results in a reduced set of ~90 timezones instead of >440 timezones and a reduced memory footprint of the package.
If you used timezonefinder for localisation beyond the timezone behavior, it might become necessary for you to individually parse the full original dataset version using the parse_data.sh script.
extended the parse_data.sh script to support downloading the timezones-now Dataset
adapted tests to the reduced dataset version
exclude tests package closing issue #330
exclude tests package closing issue #330
hit PyPI project size limit. triggering re-upload to fix missing sdist in 7.0.0 release.
hit PyPI project size limit. triggering re-upload to fix missing sdist in 7.0.0 release.
deleted all PyPI releases up to version 3.4.2 (last version supporting python 2.7) to free up project space
Simplified API for end-users, reducing redundant code
Simplified API for end-users, reducing redundant code
timezone_at
timezone_at_land
unique_timezone_at
certain_timezone_at
get_geometry
Documented usage and warned about thread safety considerations for global functions
Updated command line interface to use global functions where appropriate
breaking API Changes: clarified naming. renamed "boundary" to "bbox". renamed "polygon" to "boundary". boundaries (the outer polygon defining part of a timezone) and holes are both polygons so hence the name "polygon" is ambiguous.
when in_memory=True, all polygon numpy arrays are constructed once during startup rather than repeatedly on demand. This should significantly improve
when in_memory=True, all polygon numpy arrays are constructed once during startup rather than repeatedly on demand. This should significantly improve performance for applications that make frequent polygons queries.
Created a coord_accessors.py module for abstracting access to polygon coordinates, allowing for both in-memory and file-based access.
added auto-generated data report to the documentation. thanks to ARYAN RAJ for the PR.
hotfix missing hole_registry.json in the distributions
hotfix missing hole_registry.json in the distributions
added integration tests in CI/CD. Thanks to theirix
updated the timezone boundary data to version 2025b __. Thanks to WestonReed __
updated the timezone boundary data to version 2025b. Thanks to WestonReed
internal: updated file_converter.py for h3>=4
updated the data to 2025a
internal: updated file_converter.py for h3>=4
improved error handling to catch ValueError: not enough values to unpack (Issue #209 __)
improved error handling to catch ValueError: not enough values to unpack (Issue #209)
add musllinux Wheels for Linux. Thanks to Pxli9130 __
add musllinux Wheels for Linux. Thanks to Pxli9130
using setuptools only as a build dependency. Thanks to Kristian Sloth Lauszus __
using setuptools only as a build dependency. Thanks to Kristian Sloth Lauszus
using the dependency h3>4. Thanks to Greg Meyer __
using the dependency h3>4. Thanks to Greg Meyer
refactored C lang point in polygon utils
updated the data to 2024b.
refactored C lang point in polygon utils
added support for numpy>=2.0 (fixes issue #234)
added support for numpy>=2.0 (fixes issue #234)
added support for cibuildwheel: publish wheels including the native C extension. GHA CI/CD pipeline creates sdist (no binaries inside) and a bunch of
added support for cibuildwheel: publish wheels including the native C extension. GHA CI/CD pipeline creates sdist (no binaries inside) and a bunch of binary wheels with a prebuilt clang-pip extension for each python version. Thanks to theirix
use ruff linter in pre-commit hook
updated the data to 2024a.
internal:
use ruff linter in pre-commit hook
make dependency specifications less strict
added official support for python 3.8 again, by specifying numba as multiple constraint dependency
added official support for python 3.8 again, by specifying numba as multiple constraint dependency
internal:
added unit tests for polygon boundary binary reading
added python 3.12 support (supported by numba since release 0.59.0), Closes #208
added python 3.12 support (supported by numba since release 0.59.0), Closes #208
dropped official support for python 3.8, because the optional dependency numba requires python 3.9. this package might still work with python 3.8, but it is not tested anymore.
added docstrings. Thanks to Tyler Huntley __
updated the data to 2023d.
internal:
added docstrings. Thanks to Tyler Huntley
automatically skip GitHub actions publishing when the version already exists. useful for minor improvements without publishing a version. build would always fail otherwise
enable tests for python 3.11 with numba
enable tests for python 3.12
added tests for generating the documentation
use poetry dependency group specification (closing #199)
* updated the data to 2023b __.
updated the data to 2023b.
added a pytz extra for easily maintaining compatibility
added a pytz extra for easily maintaining compatibility
improved documentation
* updated the data to 2022g __.
updated the data to 2022g.
pumped h3 dependency to >=3.7.6,<4 to support python 3.11 (FIX #170)
pumped h3 dependency to >=3.7.6,<4 to support python 3.11 (FIX #170)
added python 3.11 tests (not yet supporting numba)
pinning dependencies more strictly
updated the data to 2022f.
pinning dependencies more strictly
* updated the data to 2022d __.
updated the data to 2022d.
logging build failures with warnings
updated the data to 2022b.
logging build failures with warnings
more permissive optional Numba dependency specification (FIX #162, impossible using latest numpy version)
more permissive optional Numba dependency specification (FIX #162, impossible using latest numpy version)
made all dependency specifications more permissive following the same rationale
bugfix broken package build in the case of a broken cffi installation (GitHub issue #155). Skip build process if cffi fails. For performance reasons u
bugfix broken package build in the case of a broken cffi installation (GitHub issue #155). Skip build process if cffi fails. For performance reasons using the C extension should remain the default behavior. Hence the cffi dependency should not be optional.
bugfix potentially broken pip install due to a mismatch in cffi versions (GitHub issue #151)
bugfix potentially broken pip install due to a mismatch in cffi versions (GitHub issue #151)
minimized and cleaned up installation footprint (addresses GitHub Issue #151):
internals:
excluded script, changelog etc. files
included C extension into the "timezonefinder" package folder
added initialisation speed benchmark
included point-in-polygon implementation in C
included point-in-polygon implementation in C
included build script to (optionally) build C point-in-polygon extension automatically during installation
added cffi as a dependency to build and interact with the C extension
improved initialisation speed: read timezone polygon id index (h3 mapping) with np.fromfile
improved CLI speed: construct TimezoneFinder() instances only on demand
internals:
updated documentation: Numba installation is no longer recommended (it is a huge dependency and should be optional)
clarified documentation: TimezoneFinder() instances should be reused
added separate speed benchmark scripts for point in polygon algorithm implementations and the different timezone finding functions
added separate section in the documentation for performance including speed benchmark results
added checks if all timezone polygons are actually in use (appear in index) to the file conversion script
added and improved utility functions as well as tests
improved typing
bump numpy dependency version to 1.22 (vulnerability fix)
bump numpy dependency version to 1.22 (vulnerability fix)
officially supported python versions >=3.8,<3.11 (due to numpy and numba constraints)
packaging now completely based on pyproject.toml (poetry)
explicitly included py.typed in the package to allow mypy users to run static type checking
explicitly included py.typed in the package to allow mypy users to run static type checking
new dependency: using h3 __ for indexing the timezone polygons to check ("shortcuts) instead of the previous own indexing implementation. technical de
breaking changes:
new dependency: using h3 for indexing the timezone polygons to check ("shortcuts) instead of the previous own indexing implementation. technical details: storing all 41,162 hex cells at resolution 3 and the corresponding timezone polygons which appear in them in the shortcuts.bin (~500 KB).
removed .closest_timezone_at(): with the current data set with ocean zones in use, any point is included in some zone. it is therefore not meaningful to search for the closest boundary! Also the timezone polygons do NOT follow the shorelines. This makes the results of closest_timezone_at() somewhat less expressive. Maintaining the non-trivial distance computation algorithms is not really at the core responsibility of this package.
officially only supporting python>=3.7 (removed official support for python3.6, since the numpy dependency did so)
removed v from the github release/version tags
internals:
updated the data to 2021c. please note that timezone polygons might be overlapping (cf. e.g. timezone-boundary-builder/issue/105) and that hence a query coordinate can actually match multiple time zones. timezonefinder does currently NOT support such multiplicity and will always only return the first found match.
shortcuts: sorting according to size of polygons (amount of coordinates) instead of the count of zone ids. useful as optimisation: smaller polygons will be checked first and can hence be "ruled-out" faster
"most common": now meaning the zone with the largest polygons in the shortcut (last in the shortcut sorting). please note that this does not necessarily mean the most area in the shortcut is covered by this zone. the polygon size is just an easier to compute heuristic.
officially supporting python versions >=3.7,<3.11 (like numba)
using poetry for dependency management
using GitHub actions for CI instead of travis
some minor typing improvements
pre-commit hook improvements
In case you have criticism or feedback please reach out by creating an issue, discussion or PR on GitHub.
added function unique_timezone_at() (based on the request in issue #112). Allows querying for the unique zone within the corresponding shortcut.
added function unique_timezone_at() (based on the request in issue #112). Allows querying for the unique zone within the corresponding shortcut.
BUGFIX: get_geometry() now also works for the last zone
BUGFIX: get_geometry() now also works for the last zone
add get_geometry() tests
black code style
pre-commit checks
update the command line interface. the package can now directly be called with timezonefinder
update the command line interface. the package can now directly be called with timezonefinder
added the new query functions to the command line interface (to match the online API)
deprecated certain_timezone_at(). only meaningful in the case of timezone data WITHOUT oceans. Has equal results as timezone_at(), but is more expensi…
MAJOR CHANGES:
Due to multiple user requests the ocean timezones ("Etc/GMT+-XX") are now included in the data files per default. fix #88. Since ocean timezones span the whole globe, now every point lies within a timezone!
API changes: * added timezone_at_land(): replaces the previous timezone_at() and returns None in case of a matched ocean timezone.
deprecated certain_timezone_at(). only meaningful in the case of timezone data WITHOUT oceans. Has equal results as timezone_at(), but is more expensive to use.
also looking a single closest timezone boundary with closest_timezone_at() is not really meaningful, since every point lies within a zone!
refactored tests. new test cases for ocean timezones
BUGFIX: handle output destination for data files correctly in file_converter.py (FIX #107)
BUGFIX: handle output destination for data files correctly in file_converter.py (FIX #107)
updated the data to 2020d
disable a test case for an Uzbek enclave. tests fail at this coordinate, possibly a bug. issue filed here: https://github.com/evansiroky/timezone-boundary-builder/issues/94
update parse_data.sh script to properly handle new data format
BUGFIX: a longitude of 180 equals -180 (not 0.0 as previously implemented)
BUGFIX: a longitude of 180 equals -180 (not 0.0 as previously implemented)
added new class TimezonefinderL for using JUST shortcuts (without timezone polygon data)
added new class TimezonefinderL for using JUST shortcuts (without timezone polygon data)
therefore included the most common timezone of each shortcut stored in the binary file shortcuts_direct_id.bin
introduced typing
included API documentation
read hole registry directly from json, hole_poly_ids.bin not required any more
added the parse_data.sh shell script for downloading the latest timezone data, also with oceans
improvements of file_converter.py:
added command line arguments for specifying the input and output directories
read binary names from global_settings.py
read data types from global_settings.py
use with statement for writing binaries
automatically detect overflow for each data type in use
cleanup code, remove redundancies, improve codestyle
fixing #101: make imports work for local and remote execution
BUGFIX #99: include the correct timezone_names.json in build
BUGFIX #99: include the correct timezone_names.json in build
wheel specific for the supported python versions (3.6, 3.7, 3.8)
added option to specify the location of the binary data files to use. making it possible to easily point to own compiled data. also load timezone name
added option to specify the location of the binary data files to use. making it possible to easily point to own compiled data. also load timezone names json from this location
make timezone names a class attribute (instead of a global variable)
simplify code for opening and closing multiple binary files
added tests for a specified path to the data
testing multiple python3 versions automatically
pinned new requirements
importlib_resources removed from the dependencies
added a documentation at: https://timezonefinder.readthedocs.io/en/latest/
added contribution guidelines
added description of using vectorized input in readme
updated the data to 2019b
added description of using vectorized input in readme
clarification of readme: referenced latest timezonefinderL release, better rst headlines, updated shield.io banner syntax
clarification of readme: referenced latest timezonefinderL release, better rst headlines, updated shield.io banner syntax
clarification of speedup times (exponential notation)
removed six and py2 dependency from tests
minor updates to publishing routine
minor improvement in timezone_at(): conversion coordinates to int later only when required
* updated the data to 2019a __
updated the data to 2019a
BUGFIX: fixing #77 (missing dependency in setup.py)
BUGFIX: fixing #77 (missing dependency in setup.py)
ATTENTION: Dropped Python2 support (#72)! six dependency no longer required.
ATTENTION: Dropped Python2 support (#72)! six dependency no longer required.
BUGFIX: fixing #74 (broken py3 with numba support)
added in_memory-mode (adapted unit tests to test both modes, added speed tests and explanation to readme)
use of timeit in speed tests for more accurate results
dropped use of kwargs_only decorator (can be implemented directly with python3)
BUGFIX: fixing #70 (broken py2.7 with numba support)
BUGFIX: fixing #70 (broken py2.7 with numba support)
added automatic tox tests for py2.7 py3 environments with numba installed
fixed coverage report
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