Tiny internal refactorings

hypothesis-python/RELEASE.rst

@@ -0,0 +1,3 @@
+RELEASE_TYPE: patch
+
+This patch does some minor internal cleanup; there is no user-visible change.

hypothesis-python/src/hypothesis/strategies/_internal/collections.py

@@ -167,11 +167,7 @@ def do_draw(self, data):
         return result
 
 
-class UniqueSampledListStrategy(ListStrategy):
-    def __init__(self, elements, min_size, max_size, keys):
-        super().__init__(elements, min_size, max_size)
-        self.keys = keys
-
+class UniqueSampledListStrategy(UniqueListStrategy):
     def do_draw(self, data):
         should_draw = cu.many(
             data,

hypothesis-python/src/hypothesis/strategies/_internal/core.py

@@ -1799,17 +1799,16 @@ def timedeltas(
 
 
 class CompositeStrategy(SearchStrategy):
-    def __init__(self, definition, label, args, kwargs):
+    def __init__(self, definition, args, kwargs):
         self.definition = definition
-        self.__label = label
         self.args = args
         self.kwargs = kwargs
 
     def do_draw(self, data):
         return self.definition(data.draw, *self.args, **self.kwargs)
 
     def calc_label(self):
-        return self.__label
+        return calc_label_from_cls(self.definition)
 
 
 @cacheable
@@ -1841,12 +1840,10 @@ def composite(f: Callable[..., Ex]) -> Callable[..., SearchStrategy[Ex]]:
     }
     new_argspec = argspec._replace(args=argspec.args[1:], annotations=annots)
 
-    label = calc_label_from_cls(f)
-
     @defines_strategy
     @define_function_signature(f.__name__, f.__doc__, new_argspec)
     def accept(*args, **kwargs):
-        return CompositeStrategy(f, label, args, kwargs)
+        return CompositeStrategy(f, args, kwargs)
 
     accept.__module__ = f.__module__
     return accept

hypothesis-python/src/hypothesis/strategies/_internal/strategies.py

@@ -547,21 +547,31 @@ def calc_is_cacheable(self, recur):
     @property
     def element_strategies(self):
         if self.__element_strategies is None:
+            # While strategies are hashable, they use object.__hash__ and are
+            # therefore distinguished only by identity.
+            #
+            # In principle we could "just" define a __hash__ method
+            # (and __eq__, but that's easy in terms of type() and hash())
+            # to make this more powerful, but this is harder than it sounds:
+            #
+            # 1. Strategies are often distinguished by non-hashable attributes,
+            #    or by attributes that have the same hash value ("^.+" / b"^.+").
+            # 2. LazyStrategy: can't reify the wrapped strategy without breaking
+            #    laziness, so there's a hash each for the lazy and the nonlazy.
+            #
+            # Having made several attempts, the minor benefits of making strategies
+            # hashable are simply not worth the engineering effort it would take.
+            # See also issues #2291 and #2327.
+            seen = {self}
             strategies = []
             for arg in self.original_strategies:
                 check_strategy(arg)
                 if not arg.is_empty:
-                    strategies.extend([s for s in arg.branches if not s.is_empty])
-            pruned = []
-            seen = set()
-            for s in strategies:
-                if s is self:
-                    continue
-                if s in seen:
-                    continue
-                seen.add(s)
-                pruned.append(s)
-            self.__element_strategies = pruned
+                    for s in arg.branches:
+                        if s not in seen and not s.is_empty:
+                            seen.add(s)
+                            strategies.append(s)
+            self.__element_strategies = strategies
         return self.__element_strategies
 
     def calc_label(self):

requirements/coverage.txt

@@ -4,10 +4,10 @@
 #
 #    pip-compile --output-file=requirements/coverage.txt requirements/coverage.in
 #
-coverage==5.0.2
+coverage==5.0.3
 lark-parser==0.7.8
 numpy==1.18.1
 pandas==0.25.3
 python-dateutil==2.8.1    # via pandas
 pytz==2019.3
-six==1.13.0               # via python-dateutil
+six==1.14.0               # via python-dateutil

requirements/test.in

@@ -3,3 +3,4 @@ sortedcontainers
 pexpect
 pytest
 pytest-xdist
+zipp < 2  # dropped support for 3.5; required via pytest via importlib-metadata

requirements/test.txt

@@ -8,18 +8,18 @@ apipkg==1.5               # via execnet
 atomicwrites==1.3.0       # via pytest
 attrs==19.3.0
 execnet==1.7.1            # via pytest-xdist
-importlib-metadata==1.3.0  # via pluggy, pytest
-more-itertools==8.0.2     # via pytest, zipp
+importlib-metadata==1.4.0  # via pluggy, pytest
+more-itertools==8.1.0     # via pytest, zipp
 packaging==20.0           # via pytest
-pexpect==4.7.0
+pexpect==4.8.0
 pluggy==0.13.1            # via pytest
 ptyprocess==0.6.0         # via pexpect
 py==1.8.1                 # via pytest
 pyparsing==2.4.6          # via packaging
 pytest-forked==1.1.3      # via pytest-xdist
 pytest-xdist==1.31.0
 pytest==5.3.2
-six==1.13.0               # via packaging, pytest-xdist
+six==1.14.0               # via packaging, pytest-xdist
 sortedcontainers==2.1.0
 wcwidth==0.1.8            # via pytest
-zipp==0.6.0               # via importlib-metadata
+zipp==1.0.0

requirements/tools.txt

@@ -14,41 +14,41 @@ babel==2.8.0              # via sphinx
 backcall==0.1.0           # via ipython
 bandit==1.6.2             # via flake8-bandit
 black==19.10b0
-blacken-docs==1.4.0
+blacken-docs==1.5.0
 bleach==3.1.0             # via readme-renderer
 certifi==2019.11.28       # via requests
 chardet==3.0.4            # via requests
 click==7.0                # via black, pip-tools, pyupio, safety
-coverage==5.0.2
+coverage==5.0.3
 decorator==4.4.1          # via ipython, traitlets
 deprecated==1.2.7         # via pygithub
 django==3.0.2
-docutils==0.15.2          # via readme-renderer, restructuredtext-lint, sphinx
+docutils==0.16            # via readme-renderer, restructuredtext-lint, sphinx
 dparse==0.4.1             # via pyupio, safety
 dpcontracts==0.6.0
 entrypoints==0.3          # via flake8
 filelock==3.0.12          # via tox
 flake8-bandit==2.1.2
 flake8-bugbear==20.1.2
-flake8-comprehensions==3.1.4
+flake8-comprehensions==3.2.2
 flake8-docstrings==1.5.0
 flake8-polyfill==1.0.2    # via flake8-bandit
 flake8==3.7.9
 gitdb2==2.0.6             # via gitpython
 gitpython==3.0.5          # via bandit
 idna==2.8                 # via requests
 imagesize==1.2.0          # via sphinx
-importlib-metadata==1.3.0  # via flake8-comprehensions, keyring, pluggy, pytest, tox, twine
+importlib-metadata==1.4.0  # via flake8-comprehensions, keyring, pluggy, pytest, tox, twine
 ipython-genutils==0.2.0   # via traitlets
 ipython==7.11.1
 isort==4.3.21
 jedi==0.15.2              # via ipython
 jinja2==2.10.3            # via pyupio, sphinx
-keyring==21.0.0           # via twine
+keyring==21.1.0           # via twine
 lark-parser==0.7.8
 markupsafe==1.1.1         # via jinja2
 mccabe==0.6.1             # via flake8
-more-itertools==8.0.2     # via pytest, zipp
+more-itertools==8.1.0     # via pytest, zipp
 mypy-extensions==0.4.3    # via mypy
 mypy==0.761
 numpy==1.18.1
@@ -57,13 +57,13 @@ parso==0.5.2              # via jedi
 pathspec==0.7.0           # via black
 pbr==5.4.4                # via stevedore
 pickleshare==0.7.5        # via ipython
-pip-tools==4.3.0
+pip-tools==4.4.0
 pkginfo==1.5.0.1          # via twine
 pluggy==0.13.1            # via pytest, tox
 prompt-toolkit==3.0.2     # via ipython
 py==1.8.1                 # via pytest, tox
 pycodestyle==2.5.0        # via flake8, flake8-bandit
-pydocstyle==5.0.1         # via flake8-docstrings
+pydocstyle==5.0.2         # via flake8-docstrings
 pyflakes==2.1.1           # via autoflake, flake8
 pygithub==1.45            # via pyupio
 pygments==2.5.2           # via ipython, readme-renderer, sphinx
@@ -73,17 +73,17 @@ pytest==5.3.2
 python-dateutil==2.8.1
 python-gitlab==1.15.0     # via pyupio
 pytz==2019.3              # via babel, django
-pyupgrade==1.25.2
+pyupgrade==1.26.1
 pyupio==1.0.2
 pywin32-ctypes==0.2.0     # via keyring
 pyyaml==5.3               # via bandit, dparse, pyupio
 readme-renderer==24.0     # via twine
-regex==2019.12.20         # via black
+regex==2020.1.8           # via black
 requests-toolbelt==0.9.1  # via twine
 requests==2.22.0
 restructuredtext-lint==1.3.0
 safety==1.8.5             # via pyupio
-six==1.13.0               # via bandit, bleach, dparse, packaging, pip-tools, pygithub, python-dateutil, python-gitlab, pyupio, readme-renderer, stevedore, tox, traitlets
+six==1.14.0               # via bandit, bleach, dparse, packaging, pip-tools, pygithub, python-dateutil, python-gitlab, pyupio, readme-renderer, stevedore, tox, traitlets
 smmap2==2.0.5             # via gitdb2
 snowballstemmer==2.0.0    # via pydocstyle, sphinx
 sortedcontainers==2.1.0
@@ -103,14 +103,14 @@ tox==3.14.3
 tqdm==4.41.1              # via pyupio, twine
 traitlets==4.3.3          # via ipython
 twine==3.1.1
-typed-ast==1.4.0          # via black, mypy
+typed-ast==1.4.1          # via black, mypy
 typing-extensions==3.7.4.1  # via mypy
-urllib3==1.25.7           # via requests
+urllib3==1.25.8           # via requests
 virtualenv==16.7.9        # via tox
 wcwidth==0.1.8            # via prompt-toolkit, pytest
 webencodings==0.5.1       # via bleach
 wrapt==1.11.2             # via deprecated
-zipp==0.6.0               # via importlib-metadata
+zipp==2.0.0               # via importlib-metadata
 
 # The following packages are considered to be unsafe in a requirements file:
-# setuptools==44.0.0        # via ipython, safety, sphinx, twine
+# setuptools