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6.128.311 Mar 20252 sources agree

For strategies which draw make recursive draws, including "recursive()" and "deferred()", we now generate examples with duplicated subtrees more often

For strategies which draw make recursive draws, including "recursive()" and "deferred()", we now generate examples with duplicated subtrees more often. This tends to uncover interesting behavior in tests.

For instance, we might now generate a tree like this more often (though the details depend on the strategy):

              ┌─────┐
       ┌──────┤  a  ├──────┐
       │      └─────┘      │
    ┌──┴──┐             ┌──┴──┐
    │  b  │             │  a  │
    └──┬──┘             └──┬──┘
  ┌────┴────┐         ┌────┴────┐

┌──┴──┐ ┌──┴──┐ ┌──┴──┐ ┌──┴──┐ │ c │ │ d │ │ b │ │ ... │ └─────┘ └─────┘ └──┬──┘ └─────┘ ┌────┴────┐ ┌──┴──┐ ┌──┴──┐ │ c │ │ d │ └─────┘ └─────┘

The canonical version of these notes (with links) is on readthedocs.

Open source →

Additional notes

For strategies which draw make recursive draws, including ~hypothesis.strategies.recursive and ~hypothesis.strategies.deferred, we now generate examples with duplicated subtrees more often. This tends to uncover interesting behavior in tests.

For instance, we might now generate a tree like this more often (though the details depend on the strategy):

               ┌─────┐
        ┌──────┤  a  ├──────┐
        │      └─────┘      │
     ┌──┴──┐             ┌──┴──┐
     │  b  │             │  a  │
     └──┬──┘             └──┬──┘
   ┌────┴────┐         ┌────┴────┐
┌──┴──┐   ┌──┴──┐   ┌──┴──┐   ┌──┴──┐
│  c  │   │  d  │   │  b  │   │ ... │
└─────┘   └─────┘   └──┬──┘   └─────┘
                  ┌────┴────┐
               ┌──┴──┐   ┌──┴──┐
               │  c  │   │  d  │
               └─────┘   └─────┘

Open source →

6.127.96 Mar 20252 sources agree

We now provide a better string representation for "one_of()" strategies, by flattening consecutive "|" combinations. For instance:

We now provide a better string representation for "one_of()" strategies, by flattening consecutive "|" combinations. For instance:

st.integers() | st.text() | st.booleans()

previously: one_of(one_of(integers(), text()), booleans())

one_of(integers(), text(), booleans())

Explicit calls to "one_of()" remain unflattened, in order to make tracking down complicated "one_of()" constructions easier:

st.one_of(st.integers(), st.one_of(st.text(), st.booleans())) one_of(integers(), one_of(text(), booleans()))

We print "one_of" in reprs (rather than "integers() | text() | ...") for consistency with reprs containing ".filter" or ".map" calls, which uses the full "one_of" to avoid ambiguity.

The canonical version of these notes (with links) is on readthedocs.

Open source →

Additional notes

We now provide a better string representation for ~hypothesis.strategies.one_of strategies, by flattening consecutive | combinations. For instance:

>>> st.integers() | st.text() | st.booleans()
# previously: one_of(one_of(integers(), text()), booleans())
one_of(integers(), text(), booleans())

Explicit calls to ~hypothesis.strategies.one_of remain unflattened, in order to make tracking down complicated ~hypothesis.strategies.one_of constructions easier:

>>> st.one_of(st.integers(), st.one_of(st.text(), st.booleans()))
one_of(integers(), one_of(text(), booleans()))

We print one_of in reprs (rather than integers() | text() | ...) for consistency with reprs containing .filter or .map calls, which uses the full one_of to avoid ambiguity.

Open source →

6.127.75 Mar 20252 sources agree

Fix a type-hinting regression from version 6.125.1, where we would no longer guarantee the type of the argument to ".filter" predicates (issue #4269).

Fix a type-hinting regression from version 6.125.1, where we would no longer guarantee the type of the argument to ".filter" predicates (issue #4269).

x was previously Unknown, but is now correctly guaranteed to be int

st.integers().filter(lambda x: x > 0)

The canonical version of these notes (with links) is on readthedocs.

Open source →

Additional notes

Fix a type-hinting regression from version 6.125.1, where we would no longer guarantee the type of the argument to .filter predicates (4269).

# x was previously Unknown, but is now correctly guaranteed to be int
st.integers().filter(lambda x: x > 0)

Open source →

6.127.123 Feb 2025

Improve the clarity of printing counterexamples in stateful testing, by avoiding confusing "Bundle" references with equivalent values drawn from a reg

Improve the clarity of printing counterexamples in stateful testing, by avoiding confusing "Bundle" references with equivalent values drawn from a regular strategy.

For example, we now print:

instead of

if the "unrelated" rule draws from a regular strategy such as "integers()" instead of the "a" bundle.

The canonical version of these notes (with links) is on readthedocs.

Open source →

Additional notes

Improve the clarity of printing counterexamples in stateful testing, by avoiding confusing ~hypothesis.stateful.Bundle references with equivalent values drawn from a regular strategy.

For example, we now print:

a_0 = state.add_to_bundle(a=0)
state.unrelated(value=0)

instead of

a_0 = state.add_to_bundle(a=0)
state.unrelated(value=a_0)

if the unrelated rule draws from a regular strategy such as ~hypothesis.strategies.integers instead of the a bundle.

Open source →

Additional notes

Improve the clarity of printing counterexamples in stateful testing , by avoiding confusing Bundle references with equivalent values drawn from a regular strategy.

For example, we now print:

a_0 = state . add_to_bundle ( a = 0 ) state . unrelated ( value = 0 )

instead of

a_0 = state . add_to_bundle ( a = 0 ) state . unrelated ( value = a_0 )

if the unrelated rule draws from a regular strategy such as integers() instead of the a bundle.

Open source →