add ydb deps

1 files changed, 1185 insertions, 0 deletions

diff --git a/contrib/python/pytest/py3/_pytest/assertion/rewrite.py b/contrib/python/pytest/py3/_pytest/assertion/rewrite.py
new file mode 100644
index 0000000000..ab83fee32b
--- /dev/null
+++ b/contrib/python/pytest/py3/_pytest/assertion/rewrite.py
@@ -0,0 +1,1185 @@
+"""Rewrite assertion AST to produce nice error messages."""
+import ast
+import errno
+import functools
+import importlib.abc
+import importlib.machinery
+import importlib.util
+import io
+import itertools
+import marshal
+import os
+import struct
+import sys
+import tokenize
+import types
+from pathlib import Path
+from pathlib import PurePath
+from typing import Callable
+from typing import Dict
+from typing import IO
+from typing import Iterable
+from typing import Iterator
+from typing import List
+from typing import Optional
+from typing import Sequence
+from typing import Set
+from typing import Tuple
+from typing import TYPE_CHECKING
+from typing import Union
+
+from _pytest._io.saferepr import DEFAULT_REPR_MAX_SIZE
+from _pytest._io.saferepr import saferepr
+from _pytest._version import version
+from _pytest.assertion import util
+from _pytest.assertion.util import (  # noqa: F401
+    format_explanation as _format_explanation,
+)
+from _pytest.config import Config
+from _pytest.main import Session
+from _pytest.pathlib import absolutepath
+from _pytest.pathlib import fnmatch_ex
+from _pytest.stash import StashKey
+
+if TYPE_CHECKING:
+    from _pytest.assertion import AssertionState
+
+if sys.version_info >= (3, 8):
+    namedExpr = ast.NamedExpr
+    astNameConstant = ast.Constant
+    astStr = ast.Constant
+    astNum = ast.Constant
+else:
+    namedExpr = ast.Expr
+    astNameConstant = ast.NameConstant
+    astStr = ast.Str
+    astNum = ast.Num
+
+
+assertstate_key = StashKey["AssertionState"]()
+
+# pytest caches rewritten pycs in pycache dirs
+PYTEST_TAG = f"{sys.implementation.cache_tag}-pytest-{version}"
+PYC_EXT = ".py" + (__debug__ and "c" or "o")
+PYC_TAIL = "." + PYTEST_TAG + PYC_EXT
+
+
+class AssertionRewritingHook(importlib.abc.MetaPathFinder, importlib.abc.Loader):
+    """PEP302/PEP451 import hook which rewrites asserts."""
+
+    def __init__(self, config: Config) -> None:
+        self.config = config
+        try:
+            self.fnpats = config.getini("python_files")
+        except ValueError:
+            self.fnpats = ["test_*.py", "*_test.py"]
+        self.session: Optional[Session] = None
+        self._rewritten_names: Dict[str, Path] = {}
+        self._must_rewrite: Set[str] = set()
+        # flag to guard against trying to rewrite a pyc file while we are already writing another pyc file,
+        # which might result in infinite recursion (#3506)
+        self._writing_pyc = False
+        self._basenames_to_check_rewrite = {"conftest"}
+        self._marked_for_rewrite_cache: Dict[str, bool] = {}
+        self._session_paths_checked = False
+
+    def set_session(self, session: Optional[Session]) -> None:
+        self.session = session
+        self._session_paths_checked = False
+
+    # Indirection so we can mock calls to find_spec originated from the hook during testing
+    _find_spec = importlib.machinery.PathFinder.find_spec
+
+    def find_spec(
+        self,
+        name: str,
+        path: Optional[Sequence[Union[str, bytes]]] = None,
+        target: Optional[types.ModuleType] = None,
+    ) -> Optional[importlib.machinery.ModuleSpec]:
+        if self._writing_pyc:
+            return None
+        state = self.config.stash[assertstate_key]
+        if self._early_rewrite_bailout(name, state):
+            return None
+        state.trace("find_module called for: %s" % name)
+
+        # Type ignored because mypy is confused about the `self` binding here.
+        spec = self._find_spec(name, path)  # type: ignore
+        if (
+            # the import machinery could not find a file to import
+            spec is None
+            # this is a namespace package (without `__init__.py`)
+            # there's nothing to rewrite there
+            or spec.origin is None
+            # we can only rewrite source files
+            or not isinstance(spec.loader, importlib.machinery.SourceFileLoader)
+            # if the file doesn't exist, we can't rewrite it
+            or not os.path.exists(spec.origin)
+        ):
+            return None
+        else:
+            fn = spec.origin
+
+        if not self._should_rewrite(name, fn, state):
+            return None
+
+        return importlib.util.spec_from_file_location(
+            name,
+            fn,
+            loader=self,
+            submodule_search_locations=spec.submodule_search_locations,
+        )
+
+    def create_module(
+        self, spec: importlib.machinery.ModuleSpec
+    ) -> Optional[types.ModuleType]:
+        return None  # default behaviour is fine
+
+    def exec_module(self, module: types.ModuleType) -> None:
+        assert module.__spec__ is not None
+        assert module.__spec__.origin is not None
+        fn = Path(module.__spec__.origin)
+        state = self.config.stash[assertstate_key]
+
+        self._rewritten_names[module.__name__] = fn
+
+        # The requested module looks like a test file, so rewrite it. This is
+        # the most magical part of the process: load the source, rewrite the
+        # asserts, and load the rewritten source. We also cache the rewritten
+        # module code in a special pyc. We must be aware of the possibility of
+        # concurrent pytest processes rewriting and loading pycs. To avoid
+        # tricky race conditions, we maintain the following invariant: The
+        # cached pyc is always a complete, valid pyc. Operations on it must be
+        # atomic. POSIX's atomic rename comes in handy.
+        write = not sys.dont_write_bytecode
+        cache_dir = get_cache_dir(fn)
+        if write:
+            ok = try_makedirs(cache_dir)
+            if not ok:
+                write = False
+                state.trace(f"read only directory: {cache_dir}")
+
+        cache_name = fn.name[:-3] + PYC_TAIL
+        pyc = cache_dir / cache_name
+        # Notice that even if we're in a read-only directory, I'm going
+        # to check for a cached pyc. This may not be optimal...
+        co = _read_pyc(fn, pyc, state.trace)
+        if co is None:
+            state.trace(f"rewriting {fn!r}")
+            source_stat, co = _rewrite_test(fn, self.config)
+            if write:
+                self._writing_pyc = True
+                try:
+                    _write_pyc(state, co, source_stat, pyc)
+                finally:
+                    self._writing_pyc = False
+        else:
+            state.trace(f"found cached rewritten pyc for {fn}")
+        exec(co, module.__dict__)
+
+    def _early_rewrite_bailout(self, name: str, state: "AssertionState") -> bool:
+        """A fast way to get out of rewriting modules.
+
+        Profiling has shown that the call to PathFinder.find_spec (inside of
+        the find_spec from this class) is a major slowdown, so, this method
+        tries to filter what we're sure won't be rewritten before getting to
+        it.
+        """
+        if self.session is not None and not self._session_paths_checked:
+            self._session_paths_checked = True
+            for initial_path in self.session._initialpaths:
+                # Make something as c:/projects/my_project/path.py ->
+                #     ['c:', 'projects', 'my_project', 'path.py']
+                parts = str(initial_path).split(os.sep)
+                # add 'path' to basenames to be checked.
+                self._basenames_to_check_rewrite.add(os.path.splitext(parts[-1])[0])
+
+        # Note: conftest already by default in _basenames_to_check_rewrite.
+        parts = name.split(".")
+        if parts[-1] in self._basenames_to_check_rewrite:
+            return False
+
+        # For matching the name it must be as if it was a filename.
+        path = PurePath(*parts).with_suffix(".py")
+
+        for pat in self.fnpats:
+            # if the pattern contains subdirectories ("tests/**.py" for example) we can't bail out based
+            # on the name alone because we need to match against the full path
+            if os.path.dirname(pat):
+                return False
+            if fnmatch_ex(pat, path):
+                return False
+
+        if self._is_marked_for_rewrite(name, state):
+            return False
+
+        state.trace(f"early skip of rewriting module: {name}")
+        return True
+
+    def _should_rewrite(self, name: str, fn: str, state: "AssertionState") -> bool:
+        # always rewrite conftest files
+        if os.path.basename(fn) == "conftest.py":
+            state.trace(f"rewriting conftest file: {fn!r}")
+            return True
+
+        if self.session is not None:
+            if self.session.isinitpath(absolutepath(fn)):
+                state.trace(f"matched test file (was specified on cmdline): {fn!r}")
+                return True
+
+        # modules not passed explicitly on the command line are only
+        # rewritten if they match the naming convention for test files
+        fn_path = PurePath(fn)
+        for pat in self.fnpats:
+            if fnmatch_ex(pat, fn_path):
+                state.trace(f"matched test file {fn!r}")
+                return True
+
+        return self._is_marked_for_rewrite(name, state)
+
+    def _is_marked_for_rewrite(self, name: str, state: "AssertionState") -> bool:
+        try:
+            return self._marked_for_rewrite_cache[name]
+        except KeyError:
+            for marked in self._must_rewrite:
+                if name == marked or name.startswith(marked + "."):
+                    state.trace(f"matched marked file {name!r} (from {marked!r})")
+                    self._marked_for_rewrite_cache[name] = True
+                    return True
+
+            self._marked_for_rewrite_cache[name] = False
+            return False
+
+    def mark_rewrite(self, *names: str) -> None:
+        """Mark import names as needing to be rewritten.
+
+        The named module or package as well as any nested modules will
+        be rewritten on import.
+        """
+        already_imported = (
+            set(names).intersection(sys.modules).difference(self._rewritten_names)
+        )
+        for name in already_imported:
+            mod = sys.modules[name]
+            if not AssertionRewriter.is_rewrite_disabled(
+                mod.__doc__ or ""
+            ) and not isinstance(mod.__loader__, type(self)):
+                self._warn_already_imported(name)
+        self._must_rewrite.update(names)
+        self._marked_for_rewrite_cache.clear()
+
+    def _warn_already_imported(self, name: str) -> None:
+        from _pytest.warning_types import PytestAssertRewriteWarning
+
+        self.config.issue_config_time_warning(
+            PytestAssertRewriteWarning(
+                "Module already imported so cannot be rewritten: %s" % name
+            ),
+            stacklevel=5,
+        )
+
+    def get_data(self, pathname: Union[str, bytes]) -> bytes:
+        """Optional PEP302 get_data API."""
+        with open(pathname, "rb") as f:
+            return f.read()
+
+    if sys.version_info >= (3, 10):
+        if sys.version_info >= (3, 12):
+            from importlib.resources.abc import TraversableResources
+        else:
+            from importlib.abc import TraversableResources
+
+        def get_resource_reader(self, name: str) -> TraversableResources:  # type: ignore
+            if sys.version_info < (3, 11):
+                from importlib.readers import FileReader
+            else:
+                from importlib.resources.readers import FileReader
+
+            return FileReader(  # type:ignore[no-any-return]
+                types.SimpleNamespace(path=self._rewritten_names[name])
+            )
+
+
+def _write_pyc_fp(
+    fp: IO[bytes], source_stat: os.stat_result, co: types.CodeType
+) -> None:
+    # Technically, we don't have to have the same pyc format as
+    # (C)Python, since these "pycs" should never be seen by builtin
+    # import. However, there's little reason to deviate.
+    fp.write(importlib.util.MAGIC_NUMBER)
+    # https://www.python.org/dev/peps/pep-0552/
+    flags = b"\x00\x00\x00\x00"
+    fp.write(flags)
+    # as of now, bytecode header expects 32-bit numbers for size and mtime (#4903)
+    mtime = int(source_stat.st_mtime) & 0xFFFFFFFF
+    size = source_stat.st_size & 0xFFFFFFFF
+    # "<LL" stands for 2 unsigned longs, little-endian.
+    fp.write(struct.pack("<LL", mtime, size))
+    fp.write(marshal.dumps(co))
+
+
+def _write_pyc(
+    state: "AssertionState",
+    co: types.CodeType,
+    source_stat: os.stat_result,
+    pyc: Path,
+) -> bool:
+    proc_pyc = f"{pyc}.{os.getpid()}"
+    try:
+        with open(proc_pyc, "wb") as fp:
+            _write_pyc_fp(fp, source_stat, co)
+    except OSError as e:
+        state.trace(f"error writing pyc file at {proc_pyc}: errno={e.errno}")
+        return False
+
+    try:
+        os.replace(proc_pyc, pyc)
+    except OSError as e:
+        state.trace(f"error writing pyc file at {pyc}: {e}")
+        # we ignore any failure to write the cache file
+        # there are many reasons, permission-denied, pycache dir being a
+        # file etc.
+        return False
+    return True
+
+
+def _rewrite_test(fn: Path, config: Config) -> Tuple[os.stat_result, types.CodeType]:
+    """Read and rewrite *fn* and return the code object."""
+    stat = os.stat(fn)
+    source = fn.read_bytes()
+    strfn = str(fn)
+    tree = ast.parse(source, filename=strfn)
+    rewrite_asserts(tree, source, strfn, config)
+    co = compile(tree, strfn, "exec", dont_inherit=True)
+    return stat, co
+
+
+def _read_pyc(
+    source: Path, pyc: Path, trace: Callable[[str], None] = lambda x: None
+) -> Optional[types.CodeType]:
+    """Possibly read a pytest pyc containing rewritten code.
+
+    Return rewritten code if successful or None if not.
+    """
+    try:
+        fp = open(pyc, "rb")
+    except OSError:
+        return None
+    with fp:
+        try:
+            stat_result = os.stat(source)
+            mtime = int(stat_result.st_mtime)
+            size = stat_result.st_size
+            data = fp.read(16)
+        except OSError as e:
+            trace(f"_read_pyc({source}): OSError {e}")
+            return None
+        # Check for invalid or out of date pyc file.
+        if len(data) != (16):
+            trace("_read_pyc(%s): invalid pyc (too short)" % source)
+            return None
+        if data[:4] != importlib.util.MAGIC_NUMBER:
+            trace("_read_pyc(%s): invalid pyc (bad magic number)" % source)
+            return None
+        if data[4:8] != b"\x00\x00\x00\x00":
+            trace("_read_pyc(%s): invalid pyc (unsupported flags)" % source)
+            return None
+        mtime_data = data[8:12]
+        if int.from_bytes(mtime_data, "little") != mtime & 0xFFFFFFFF:
+            trace("_read_pyc(%s): out of date" % source)
+            return None
+        size_data = data[12:16]
+        if int.from_bytes(size_data, "little") != size & 0xFFFFFFFF:
+            trace("_read_pyc(%s): invalid pyc (incorrect size)" % source)
+            return None
+        try:
+            co = marshal.load(fp)
+        except Exception as e:
+            trace(f"_read_pyc({source}): marshal.load error {e}")
+            return None
+        if not isinstance(co, types.CodeType):
+            trace("_read_pyc(%s): not a code object" % source)
+            return None
+        return co
+
+
+def rewrite_asserts(
+    mod: ast.Module,
+    source: bytes,
+    module_path: Optional[str] = None,
+    config: Optional[Config] = None,
+) -> None:
+    """Rewrite the assert statements in mod."""
+    AssertionRewriter(module_path, config, source).run(mod)
+
+
+def _saferepr(obj: object) -> str:
+    r"""Get a safe repr of an object for assertion error messages.
+
+    The assertion formatting (util.format_explanation()) requires
+    newlines to be escaped since they are a special character for it.
+    Normally assertion.util.format_explanation() does this but for a
+    custom repr it is possible to contain one of the special escape
+    sequences, especially '\n{' and '\n}' are likely to be present in
+    JSON reprs.
+    """
+    maxsize = _get_maxsize_for_saferepr(util._config)
+    return saferepr(obj, maxsize=maxsize).replace("\n", "\\n")
+
+
+def _get_maxsize_for_saferepr(config: Optional[Config]) -> Optional[int]:
+    """Get `maxsize` configuration for saferepr based on the given config object."""
+    verbosity = config.getoption("verbose") if config is not None else 0
+    if verbosity >= 2:
+        return None
+    if verbosity >= 1:
+        return DEFAULT_REPR_MAX_SIZE * 10
+    return DEFAULT_REPR_MAX_SIZE
+
+
+def _format_assertmsg(obj: object) -> str:
+    r"""Format the custom assertion message given.
+
+    For strings this simply replaces newlines with '\n~' so that
+    util.format_explanation() will preserve them instead of escaping
+    newlines.  For other objects saferepr() is used first.
+    """
+    # reprlib appears to have a bug which means that if a string
+    # contains a newline it gets escaped, however if an object has a
+    # .__repr__() which contains newlines it does not get escaped.
+    # However in either case we want to preserve the newline.
+    replaces = [("\n", "\n~"), ("%", "%%")]
+    if not isinstance(obj, str):
+        obj = saferepr(obj)
+        replaces.append(("\\n", "\n~"))
+
+    for r1, r2 in replaces:
+        obj = obj.replace(r1, r2)
+
+    return obj
+
+
+def _should_repr_global_name(obj: object) -> bool:
+    if callable(obj):
+        return False
+
+    try:
+        return not hasattr(obj, "__name__")
+    except Exception:
+        return True
+
+
+def _format_boolop(explanations: Iterable[str], is_or: bool) -> str:
+    explanation = "(" + (is_or and " or " or " and ").join(explanations) + ")"
+    return explanation.replace("%", "%%")
+
+
+def _call_reprcompare(
+    ops: Sequence[str],
+    results: Sequence[bool],
+    expls: Sequence[str],
+    each_obj: Sequence[object],
+) -> str:
+    for i, res, expl in zip(range(len(ops)), results, expls):
+        try:
+            done = not res
+        except Exception:
+            done = True
+        if done:
+            break
+    if util._reprcompare is not None:
+        custom = util._reprcompare(ops[i], each_obj[i], each_obj[i + 1])
+        if custom is not None:
+            return custom
+    return expl
+
+
+def _call_assertion_pass(lineno: int, orig: str, expl: str) -> None:
+    if util._assertion_pass is not None:
+        util._assertion_pass(lineno, orig, expl)
+
+
+def _check_if_assertion_pass_impl() -> bool:
+    """Check if any plugins implement the pytest_assertion_pass hook
+    in order not to generate explanation unnecessarily (might be expensive)."""
+    return True if util._assertion_pass else False
+
+
+UNARY_MAP = {ast.Not: "not %s", ast.Invert: "~%s", ast.USub: "-%s", ast.UAdd: "+%s"}
+
+BINOP_MAP = {
+    ast.BitOr: "|",
+    ast.BitXor: "^",
+    ast.BitAnd: "&",
+    ast.LShift: "<<",
+    ast.RShift: ">>",
+    ast.Add: "+",
+    ast.Sub: "-",
+    ast.Mult: "*",
+    ast.Div: "/",
+    ast.FloorDiv: "//",
+    ast.Mod: "%%",  # escaped for string formatting
+    ast.Eq: "==",
+    ast.NotEq: "!=",
+    ast.Lt: "<",
+    ast.LtE: "<=",
+    ast.Gt: ">",
+    ast.GtE: ">=",
+    ast.Pow: "**",
+    ast.Is: "is",
+    ast.IsNot: "is not",
+    ast.In: "in",
+    ast.NotIn: "not in",
+    ast.MatMult: "@",
+}
+
+
+def traverse_node(node: ast.AST) -> Iterator[ast.AST]:
+    """Recursively yield node and all its children in depth-first order."""
+    yield node
+    for child in ast.iter_child_nodes(node):
+        yield from traverse_node(child)
+
+
+@functools.lru_cache(maxsize=1)
+def _get_assertion_exprs(src: bytes) -> Dict[int, str]:
+    """Return a mapping from {lineno: "assertion test expression"}."""
+    ret: Dict[int, str] = {}
+
+    depth = 0
+    lines: List[str] = []
+    assert_lineno: Optional[int] = None
+    seen_lines: Set[int] = set()
+
+    def _write_and_reset() -> None:
+        nonlocal depth, lines, assert_lineno, seen_lines
+        assert assert_lineno is not None
+        ret[assert_lineno] = "".join(lines).rstrip().rstrip("\\")
+        depth = 0
+        lines = []
+        assert_lineno = None
+        seen_lines = set()
+
+    tokens = tokenize.tokenize(io.BytesIO(src).readline)
+    for tp, source, (lineno, offset), _, line in tokens:
+        if tp == tokenize.NAME and source == "assert":
+            assert_lineno = lineno
+        elif assert_lineno is not None:
+            # keep track of depth for the assert-message `,` lookup
+            if tp == tokenize.OP and source in "([{":
+                depth += 1
+            elif tp == tokenize.OP and source in ")]}":
+                depth -= 1
+
+            if not lines:
+                lines.append(line[offset:])
+                seen_lines.add(lineno)
+            # a non-nested comma separates the expression from the message
+            elif depth == 0 and tp == tokenize.OP and source == ",":
+                # one line assert with message
+                if lineno in seen_lines and len(lines) == 1:
+                    offset_in_trimmed = offset + len(lines[-1]) - len(line)
+                    lines[-1] = lines[-1][:offset_in_trimmed]
+                # multi-line assert with message
+                elif lineno in seen_lines:
+                    lines[-1] = lines[-1][:offset]
+                # multi line assert with escapd newline before message
+                else:
+                    lines.append(line[:offset])
+                _write_and_reset()
+            elif tp in {tokenize.NEWLINE, tokenize.ENDMARKER}:
+                _write_and_reset()
+            elif lines and lineno not in seen_lines:
+                lines.append(line)
+                seen_lines.add(lineno)
+
+    return ret
+
+
+class AssertionRewriter(ast.NodeVisitor):
+    """Assertion rewriting implementation.
+
+    The main entrypoint is to call .run() with an ast.Module instance,
+    this will then find all the assert statements and rewrite them to
+    provide intermediate values and a detailed assertion error.  See
+    http://pybites.blogspot.be/2011/07/behind-scenes-of-pytests-new-assertion.html
+    for an overview of how this works.
+
+    The entry point here is .run() which will iterate over all the
+    statements in an ast.Module and for each ast.Assert statement it
+    finds call .visit() with it.  Then .visit_Assert() takes over and
+    is responsible for creating new ast statements to replace the
+    original assert statement: it rewrites the test of an assertion
+    to provide intermediate values and replace it with an if statement
+    which raises an assertion error with a detailed explanation in
+    case the expression is false and calls pytest_assertion_pass hook
+    if expression is true.
+
+    For this .visit_Assert() uses the visitor pattern to visit all the
+    AST nodes of the ast.Assert.test field, each visit call returning
+    an AST node and the corresponding explanation string.  During this
+    state is kept in several instance attributes:
+
+    :statements: All the AST statements which will replace the assert
+       statement.
+
+    :variables: This is populated by .variable() with each variable
+       used by the statements so that they can all be set to None at
+       the end of the statements.
+
+    :variable_counter: Counter to create new unique variables needed
+       by statements.  Variables are created using .variable() and
+       have the form of "@py_assert0".
+
+    :expl_stmts: The AST statements which will be executed to get
+       data from the assertion.  This is the code which will construct
+       the detailed assertion message that is used in the AssertionError
+       or for the pytest_assertion_pass hook.
+
+    :explanation_specifiers: A dict filled by .explanation_param()
+       with %-formatting placeholders and their corresponding
+       expressions to use in the building of an assertion message.
+       This is used by .pop_format_context() to build a message.
+
+    :stack: A stack of the explanation_specifiers dicts maintained by
+       .push_format_context() and .pop_format_context() which allows
+       to build another %-formatted string while already building one.
+
+    :variables_overwrite: A dict filled with references to variables
+       that change value within an assert. This happens when a variable is
+       reassigned with the walrus operator
+
+    This state, except the variables_overwrite,  is reset on every new assert
+    statement visited and used by the other visitors.
+    """
+
+    def __init__(
+        self, module_path: Optional[str], config: Optional[Config], source: bytes
+    ) -> None:
+        super().__init__()
+        self.module_path = module_path
+        self.config = config
+        if config is not None:
+            self.enable_assertion_pass_hook = config.getini(
+                "enable_assertion_pass_hook"
+            )
+        else:
+            self.enable_assertion_pass_hook = False
+        self.source = source
+        self.variables_overwrite: Dict[str, str] = {}
+
+    def run(self, mod: ast.Module) -> None:
+        """Find all assert statements in *mod* and rewrite them."""
+        if not mod.body:
+            # Nothing to do.
+            return
+
+        # We'll insert some special imports at the top of the module, but after any
+        # docstrings and __future__ imports, so first figure out where that is.
+        doc = getattr(mod, "docstring", None)
+        expect_docstring = doc is None
+        if doc is not None and self.is_rewrite_disabled(doc):
+            return
+        pos = 0
+        item = None
+        for item in mod.body:
+            if (
+                expect_docstring
+                and isinstance(item, ast.Expr)
+                and isinstance(item.value, astStr)
+            ):
+                if sys.version_info >= (3, 8):
+                    doc = item.value.value
+                else:
+                    doc = item.value.s
+                if self.is_rewrite_disabled(doc):
+                    return
+                expect_docstring = False
+            elif (
+                isinstance(item, ast.ImportFrom)
+                and item.level == 0
+                and item.module == "__future__"
+            ):
+                pass
+            else:
+                break
+            pos += 1
+        # Special case: for a decorated function, set the lineno to that of the
+        # first decorator, not the `def`. Issue #4984.
+        if isinstance(item, ast.FunctionDef) and item.decorator_list:
+            lineno = item.decorator_list[0].lineno
+        else:
+            lineno = item.lineno
+        # Now actually insert the special imports.
+        if sys.version_info >= (3, 10):
+            aliases = [
+                ast.alias("builtins", "@py_builtins", lineno=lineno, col_offset=0),
+                ast.alias(
+                    "_pytest.assertion.rewrite",
+                    "@pytest_ar",
+                    lineno=lineno,
+                    col_offset=0,
+                ),
+            ]
+        else:
+            aliases = [
+                ast.alias("builtins", "@py_builtins"),
+                ast.alias("_pytest.assertion.rewrite", "@pytest_ar"),
+            ]
+        imports = [
+            ast.Import([alias], lineno=lineno, col_offset=0) for alias in aliases
+        ]
+        mod.body[pos:pos] = imports
+
+        # Collect asserts.
+        nodes: List[ast.AST] = [mod]
+        while nodes:
+            node = nodes.pop()
+            for name, field in ast.iter_fields(node):
+                if isinstance(field, list):
+                    new: List[ast.AST] = []
+                    for i, child in enumerate(field):
+                        if isinstance(child, ast.Assert):
+                            # Transform assert.
+                            new.extend(self.visit(child))
+                        else:
+                            new.append(child)
+                            if isinstance(child, ast.AST):
+                                nodes.append(child)
+                    setattr(node, name, new)
+                elif (
+                    isinstance(field, ast.AST)
+                    # Don't recurse into expressions as they can't contain
+                    # asserts.
+                    and not isinstance(field, ast.expr)
+                ):
+                    nodes.append(field)
+
+    @staticmethod
+    def is_rewrite_disabled(docstring: str) -> bool:
+        return "PYTEST_DONT_REWRITE" in docstring
+
+    def variable(self) -> str:
+        """Get a new variable."""
+        # Use a character invalid in python identifiers to avoid clashing.
+        name = "@py_assert" + str(next(self.variable_counter))
+        self.variables.append(name)
+        return name
+
+    def assign(self, expr: ast.expr) -> ast.Name:
+        """Give *expr* a name."""
+        name = self.variable()
+        self.statements.append(ast.Assign([ast.Name(name, ast.Store())], expr))
+        return ast.Name(name, ast.Load())
+
+    def display(self, expr: ast.expr) -> ast.expr:
+        """Call saferepr on the expression."""
+        return self.helper("_saferepr", expr)
+
+    def helper(self, name: str, *args: ast.expr) -> ast.expr:
+        """Call a helper in this module."""
+        py_name = ast.Name("@pytest_ar", ast.Load())
+        attr = ast.Attribute(py_name, name, ast.Load())
+        return ast.Call(attr, list(args), [])
+
+    def builtin(self, name: str) -> ast.Attribute:
+        """Return the builtin called *name*."""
+        builtin_name = ast.Name("@py_builtins", ast.Load())
+        return ast.Attribute(builtin_name, name, ast.Load())
+
+    def explanation_param(self, expr: ast.expr) -> str:
+        """Return a new named %-formatting placeholder for expr.
+
+        This creates a %-formatting placeholder for expr in the
+        current formatting context, e.g. ``%(py0)s``.  The placeholder
+        and expr are placed in the current format context so that it
+        can be used on the next call to .pop_format_context().
+        """
+        specifier = "py" + str(next(self.variable_counter))
+        self.explanation_specifiers[specifier] = expr
+        return "%(" + specifier + ")s"
+
+    def push_format_context(self) -> None:
+        """Create a new formatting context.
+
+        The format context is used for when an explanation wants to
+        have a variable value formatted in the assertion message.  In
+        this case the value required can be added using
+        .explanation_param().  Finally .pop_format_context() is used
+        to format a string of %-formatted values as added by
+        .explanation_param().
+        """
+        self.explanation_specifiers: Dict[str, ast.expr] = {}
+        self.stack.append(self.explanation_specifiers)
+
+    def pop_format_context(self, expl_expr: ast.expr) -> ast.Name:
+        """Format the %-formatted string with current format context.
+
+        The expl_expr should be an str ast.expr instance constructed from
+        the %-placeholders created by .explanation_param().  This will
+        add the required code to format said string to .expl_stmts and
+        return the ast.Name instance of the formatted string.
+        """
+        current = self.stack.pop()
+        if self.stack:
+            self.explanation_specifiers = self.stack[-1]
+        keys = [astStr(key) for key in current.keys()]
+        format_dict = ast.Dict(keys, list(current.values()))
+        form = ast.BinOp(expl_expr, ast.Mod(), format_dict)
+        name = "@py_format" + str(next(self.variable_counter))
+        if self.enable_assertion_pass_hook:
+            self.format_variables.append(name)
+        self.expl_stmts.append(ast.Assign([ast.Name(name, ast.Store())], form))
+        return ast.Name(name, ast.Load())
+
+    def generic_visit(self, node: ast.AST) -> Tuple[ast.Name, str]:
+        """Handle expressions we don't have custom code for."""
+        assert isinstance(node, ast.expr)
+        res = self.assign(node)
+        return res, self.explanation_param(self.display(res))
+
+    def visit_Assert(self, assert_: ast.Assert) -> List[ast.stmt]:
+        """Return the AST statements to replace the ast.Assert instance.
+
+        This rewrites the test of an assertion to provide
+        intermediate values and replace it with an if statement which
+        raises an assertion error with a detailed explanation in case
+        the expression is false.
+        """
+        if isinstance(assert_.test, ast.Tuple) and len(assert_.test.elts) >= 1:
+            from _pytest.warning_types import PytestAssertRewriteWarning
+            import warnings
+
+            # TODO: This assert should not be needed.
+            assert self.module_path is not None
+            warnings.warn_explicit(
+                PytestAssertRewriteWarning(
+                    "assertion is always true, perhaps remove parentheses?"
+                ),
+                category=None,
+                filename=self.module_path,
+                lineno=assert_.lineno,
+            )
+
+        self.statements: List[ast.stmt] = []
+        self.variables: List[str] = []
+        self.variable_counter = itertools.count()
+
+        if self.enable_assertion_pass_hook:
+            self.format_variables: List[str] = []
+
+        self.stack: List[Dict[str, ast.expr]] = []
+        self.expl_stmts: List[ast.stmt] = []
+        self.push_format_context()
+        # Rewrite assert into a bunch of statements.
+        top_condition, explanation = self.visit(assert_.test)
+
+        negation = ast.UnaryOp(ast.Not(), top_condition)
+
+        if self.enable_assertion_pass_hook:  # Experimental pytest_assertion_pass hook
+            msg = self.pop_format_context(astStr(explanation))
+
+            # Failed
+            if assert_.msg:
+                assertmsg = self.helper("_format_assertmsg", assert_.msg)
+                gluestr = "\n>assert "
+            else:
+                assertmsg = astStr("")
+                gluestr = "assert "
+            err_explanation = ast.BinOp(astStr(gluestr), ast.Add(), msg)
+            err_msg = ast.BinOp(assertmsg, ast.Add(), err_explanation)
+            err_name = ast.Name("AssertionError", ast.Load())
+            fmt = self.helper("_format_explanation", err_msg)
+            exc = ast.Call(err_name, [fmt], [])
+            raise_ = ast.Raise(exc, None)
+            statements_fail = []
+            statements_fail.extend(self.expl_stmts)
+            statements_fail.append(raise_)
+
+            # Passed
+            fmt_pass = self.helper("_format_explanation", msg)
+            orig = _get_assertion_exprs(self.source)[assert_.lineno]
+            hook_call_pass = ast.Expr(
+                self.helper(
+                    "_call_assertion_pass",
+                    astNum(assert_.lineno),
+                    astStr(orig),
+                    fmt_pass,
+                )
+            )
+            # If any hooks implement assert_pass hook
+            hook_impl_test = ast.If(
+                self.helper("_check_if_assertion_pass_impl"),
+                self.expl_stmts + [hook_call_pass],
+                [],
+            )
+            statements_pass = [hook_impl_test]
+
+            # Test for assertion condition
+            main_test = ast.If(negation, statements_fail, statements_pass)
+            self.statements.append(main_test)
+            if self.format_variables:
+                variables = [
+                    ast.Name(name, ast.Store()) for name in self.format_variables
+                ]
+                clear_format = ast.Assign(variables, astNameConstant(None))
+                self.statements.append(clear_format)
+
+        else:  # Original assertion rewriting
+            # Create failure message.
+            body = self.expl_stmts
+            self.statements.append(ast.If(negation, body, []))
+            if assert_.msg:
+                assertmsg = self.helper("_format_assertmsg", assert_.msg)
+                explanation = "\n>assert " + explanation
+            else:
+                assertmsg = astStr("")
+                explanation = "assert " + explanation
+            template = ast.BinOp(assertmsg, ast.Add(), astStr(explanation))
+            msg = self.pop_format_context(template)
+            fmt = self.helper("_format_explanation", msg)
+            err_name = ast.Name("AssertionError", ast.Load())
+            exc = ast.Call(err_name, [fmt], [])
+            raise_ = ast.Raise(exc, None)
+
+            body.append(raise_)
+
+        # Clear temporary variables by setting them to None.
+        if self.variables:
+            variables = [ast.Name(name, ast.Store()) for name in self.variables]
+            clear = ast.Assign(variables, astNameConstant(None))
+            self.statements.append(clear)
+        # Fix locations (line numbers/column offsets).
+        for stmt in self.statements:
+            for node in traverse_node(stmt):
+                ast.copy_location(node, assert_)
+        return self.statements
+
+    def visit_NamedExpr(self, name: namedExpr) -> Tuple[namedExpr, str]:
+        # This method handles the 'walrus operator' repr of the target
+        # name if it's a local variable or _should_repr_global_name()
+        # thinks it's acceptable.
+        locs = ast.Call(self.builtin("locals"), [], [])
+        target_id = name.target.id  # type: ignore[attr-defined]
+        inlocs = ast.Compare(astStr(target_id), [ast.In()], [locs])
+        dorepr = self.helper("_should_repr_global_name", name)
+        test = ast.BoolOp(ast.Or(), [inlocs, dorepr])
+        expr = ast.IfExp(test, self.display(name), astStr(target_id))
+        return name, self.explanation_param(expr)
+
+    def visit_Name(self, name: ast.Name) -> Tuple[ast.Name, str]:
+        # Display the repr of the name if it's a local variable or
+        # _should_repr_global_name() thinks it's acceptable.
+        locs = ast.Call(self.builtin("locals"), [], [])
+        inlocs = ast.Compare(astStr(name.id), [ast.In()], [locs])
+        dorepr = self.helper("_should_repr_global_name", name)
+        test = ast.BoolOp(ast.Or(), [inlocs, dorepr])
+        expr = ast.IfExp(test, self.display(name), astStr(name.id))
+        return name, self.explanation_param(expr)
+
+    def visit_BoolOp(self, boolop: ast.BoolOp) -> Tuple[ast.Name, str]:
+        res_var = self.variable()
+        expl_list = self.assign(ast.List([], ast.Load()))
+        app = ast.Attribute(expl_list, "append", ast.Load())
+        is_or = int(isinstance(boolop.op, ast.Or))
+        body = save = self.statements
+        fail_save = self.expl_stmts
+        levels = len(boolop.values) - 1
+        self.push_format_context()
+        # Process each operand, short-circuiting if needed.
+        for i, v in enumerate(boolop.values):
+            if i:
+                fail_inner: List[ast.stmt] = []
+                # cond is set in a prior loop iteration below
+                self.expl_stmts.append(ast.If(cond, fail_inner, []))  # noqa
+                self.expl_stmts = fail_inner
+                # Check if the left operand is a namedExpr and the value has already been visited
+                if (
+                    isinstance(v, ast.Compare)
+                    and isinstance(v.left, namedExpr)
+                    and v.left.target.id
+                    in [
+                        ast_expr.id
+                        for ast_expr in boolop.values[:i]
+                        if hasattr(ast_expr, "id")
+                    ]
+                ):
+                    pytest_temp = self.variable()
+                    self.variables_overwrite[
+                        v.left.target.id
+                    ] = v.left  # type:ignore[assignment]
+                    v.left.target.id = pytest_temp
+            self.push_format_context()
+            res, expl = self.visit(v)
+            body.append(ast.Assign([ast.Name(res_var, ast.Store())], res))
+            expl_format = self.pop_format_context(astStr(expl))
+            call = ast.Call(app, [expl_format], [])
+            self.expl_stmts.append(ast.Expr(call))
+            if i < levels:
+                cond: ast.expr = res
+                if is_or:
+                    cond = ast.UnaryOp(ast.Not(), cond)
+                inner: List[ast.stmt] = []
+                self.statements.append(ast.If(cond, inner, []))
+                self.statements = body = inner
+        self.statements = save
+        self.expl_stmts = fail_save
+        expl_template = self.helper("_format_boolop", expl_list, astNum(is_or))
+        expl = self.pop_format_context(expl_template)
+        return ast.Name(res_var, ast.Load()), self.explanation_param(expl)
+
+    def visit_UnaryOp(self, unary: ast.UnaryOp) -> Tuple[ast.Name, str]:
+        pattern = UNARY_MAP[unary.op.__class__]
+        operand_res, operand_expl = self.visit(unary.operand)
+        res = self.assign(ast.UnaryOp(unary.op, operand_res))
+        return res, pattern % (operand_expl,)
+
+    def visit_BinOp(self, binop: ast.BinOp) -> Tuple[ast.Name, str]:
+        symbol = BINOP_MAP[binop.op.__class__]
+        left_expr, left_expl = self.visit(binop.left)
+        right_expr, right_expl = self.visit(binop.right)
+        explanation = f"({left_expl} {symbol} {right_expl})"
+        res = self.assign(ast.BinOp(left_expr, binop.op, right_expr))
+        return res, explanation
+
+    def visit_Call(self, call: ast.Call) -> Tuple[ast.Name, str]:
+        new_func, func_expl = self.visit(call.func)
+        arg_expls = []
+        new_args = []
+        new_kwargs = []
+        for arg in call.args:
+            if isinstance(arg, ast.Name) and arg.id in self.variables_overwrite:
+                arg = self.variables_overwrite[arg.id]  # type:ignore[assignment]
+            res, expl = self.visit(arg)
+            arg_expls.append(expl)
+            new_args.append(res)
+        for keyword in call.keywords:
+            if (
+                isinstance(keyword.value, ast.Name)
+                and keyword.value.id in self.variables_overwrite
+            ):
+                keyword.value = self.variables_overwrite[
+                    keyword.value.id
+                ]  # type:ignore[assignment]
+            res, expl = self.visit(keyword.value)
+            new_kwargs.append(ast.keyword(keyword.arg, res))
+            if keyword.arg:
+                arg_expls.append(keyword.arg + "=" + expl)
+            else:  # **args have `arg` keywords with an .arg of None
+                arg_expls.append("**" + expl)
+
+        expl = "{}({})".format(func_expl, ", ".join(arg_expls))
+        new_call = ast.Call(new_func, new_args, new_kwargs)
+        res = self.assign(new_call)
+        res_expl = self.explanation_param(self.display(res))
+        outer_expl = f"{res_expl}\n{{{res_expl} = {expl}\n}}"
+        return res, outer_expl
+
+    def visit_Starred(self, starred: ast.Starred) -> Tuple[ast.Starred, str]:
+        # A Starred node can appear in a function call.
+        res, expl = self.visit(starred.value)
+        new_starred = ast.Starred(res, starred.ctx)
+        return new_starred, "*" + expl
+
+    def visit_Attribute(self, attr: ast.Attribute) -> Tuple[ast.Name, str]:
+        if not isinstance(attr.ctx, ast.Load):
+            return self.generic_visit(attr)
+        value, value_expl = self.visit(attr.value)
+        res = self.assign(ast.Attribute(value, attr.attr, ast.Load()))
+        res_expl = self.explanation_param(self.display(res))
+        pat = "%s\n{%s = %s.%s\n}"
+        expl = pat % (res_expl, res_expl, value_expl, attr.attr)
+        return res, expl
+
+    def visit_Compare(self, comp: ast.Compare) -> Tuple[ast.expr, str]:
+        self.push_format_context()
+        # We first check if we have overwritten a variable in the previous assert
+        if isinstance(comp.left, ast.Name) and comp.left.id in self.variables_overwrite:
+            comp.left = self.variables_overwrite[
+                comp.left.id
+            ]  # type:ignore[assignment]
+        if isinstance(comp.left, namedExpr):
+            self.variables_overwrite[
+                comp.left.target.id
+            ] = comp.left  # type:ignore[assignment]
+        left_res, left_expl = self.visit(comp.left)
+        if isinstance(comp.left, (ast.Compare, ast.BoolOp)):
+            left_expl = f"({left_expl})"
+        res_variables = [self.variable() for i in range(len(comp.ops))]
+        load_names = [ast.Name(v, ast.Load()) for v in res_variables]
+        store_names = [ast.Name(v, ast.Store()) for v in res_variables]
+        it = zip(range(len(comp.ops)), comp.ops, comp.comparators)
+        expls = []
+        syms = []
+        results = [left_res]
+        for i, op, next_operand in it:
+            if (
+                isinstance(next_operand, namedExpr)
+                and isinstance(left_res, ast.Name)
+                and next_operand.target.id == left_res.id
+            ):
+                next_operand.target.id = self.variable()
+                self.variables_overwrite[
+                    left_res.id
+                ] = next_operand  # type:ignore[assignment]
+            next_res, next_expl = self.visit(next_operand)
+            if isinstance(next_operand, (ast.Compare, ast.BoolOp)):
+                next_expl = f"({next_expl})"
+            results.append(next_res)
+            sym = BINOP_MAP[op.__class__]
+            syms.append(astStr(sym))
+            expl = f"{left_expl} {sym} {next_expl}"
+            expls.append(astStr(expl))
+            res_expr = ast.Compare(left_res, [op], [next_res])
+            self.statements.append(ast.Assign([store_names[i]], res_expr))
+            left_res, left_expl = next_res, next_expl
+        # Use pytest.assertion.util._reprcompare if that's available.
+        expl_call = self.helper(
+            "_call_reprcompare",
+            ast.Tuple(syms, ast.Load()),
+            ast.Tuple(load_names, ast.Load()),
+            ast.Tuple(expls, ast.Load()),
+            ast.Tuple(results, ast.Load()),
+        )
+        if len(comp.ops) > 1:
+            res: ast.expr = ast.BoolOp(ast.And(), load_names)
+        else:
+            res = load_names[0]
+
+        return res, self.explanation_param(self.pop_format_context(expl_call))
+
+
+def try_makedirs(cache_dir: Path) -> bool:
+    """Attempt to create the given directory and sub-directories exist.
+
+    Returns True if successful or if it already exists.
+    """
+    try:
+        os.makedirs(cache_dir, exist_ok=True)
+    except (FileNotFoundError, NotADirectoryError, FileExistsError):
+        # One of the path components was not a directory:
+        # - we're in a zip file
+        # - it is a file
+        return False
+    except PermissionError:
+        return False
+    except OSError as e:
+        # as of now, EROFS doesn't have an equivalent OSError-subclass
+        if e.errno == errno.EROFS:
+            return False
+        raise
+    return True
+
+
+def get_cache_dir(file_path: Path) -> Path:
+    """Return the cache directory to write .pyc files for the given .py file path."""
+    if sys.version_info >= (3, 8) and sys.pycache_prefix:
+        # given:
+        #   prefix = '/tmp/pycs'
+        #   path = '/home/user/proj/test_app.py'
+        # we want:
+        #   '/tmp/pycs/home/user/proj'
+        return Path(sys.pycache_prefix) / Path(*file_path.parts[1:-1])
+    else:
+        # classic pycache directory
+        return file_path.parent / "__pycache__"