Major fixes and new features

venv/lib/python3.12/site-packages/coverage/phystokens.py

@@ -0,0 +1,200 @@
+# Licensed under the Apache License: http://www.apache.org/licenses/LICENSE-2.0
+# For details: https://github.com/nedbat/coveragepy/blob/master/NOTICE.txt
+
+"""Better tokenizing for coverage.py."""
+
+from __future__ import annotations
+
+import ast
+import io
+import keyword
+import re
+import sys
+import token
+import tokenize
+from collections.abc import Iterable
+
+from coverage import env
+from coverage.types import TLineNo, TSourceTokenLines
+
+TokenInfos = Iterable[tokenize.TokenInfo]
+
+
+def _phys_tokens(toks: TokenInfos) -> TokenInfos:
+    """Return all physical tokens, even line continuations.
+
+    tokenize.generate_tokens() doesn't return a token for the backslash that
+    continues lines.  This wrapper provides those tokens so that we can
+    re-create a faithful representation of the original source.
+
+    Returns the same values as generate_tokens()
+
+    """
+    last_line: str | None = None
+    last_lineno = -1
+    last_ttext: str = ""
+    for ttype, ttext, (slineno, scol), (elineno, ecol), ltext in toks:
+        if last_lineno != elineno:
+            if last_line and last_line.endswith("\\\n"):
+                # We are at the beginning of a new line, and the last line
+                # ended with a backslash.  We probably have to inject a
+                # backslash token into the stream. Unfortunately, there's more
+                # to figure out.  This code::
+                #
+                #   usage = """\
+                #   HEY THERE
+                #   """
+                #
+                # triggers this condition, but the token text is::
+                #
+                #   '"""\\\nHEY THERE\n"""'
+                #
+                # so we need to figure out if the backslash is already in the
+                # string token or not.
+                inject_backslash = True
+                if last_ttext.endswith("\\"):
+                    inject_backslash = False
+                elif ttype == token.STRING:
+                    if (  # pylint: disable=simplifiable-if-statement
+                        last_line.endswith("\\\n")
+                        and last_line.rstrip(" \\\n").endswith(last_ttext)
+                    ):
+                        # Deal with special cases like such code::
+                        #
+                        #   a = ["aaa",\ # there may be zero or more blanks between "," and "\".
+                        #        "bbb \
+                        #        ccc"]
+                        #
+                        inject_backslash = True
+                    else:
+                        # It's a multi-line string and the first line ends with
+                        # a backslash, so we don't need to inject another.
+                        inject_backslash = False
+                elif env.PYBEHAVIOR.fstring_syntax and ttype == token.FSTRING_MIDDLE:
+                    inject_backslash = False
+                if inject_backslash:
+                    # Figure out what column the backslash is in.
+                    ccol = len(last_line.split("\n")[-2]) - 1
+                    # Yield the token, with a fake token type.
+                    yield tokenize.TokenInfo(
+                        99999,
+                        "\\\n",
+                        (slineno, ccol),
+                        (slineno, ccol + 2),
+                        last_line,
+                    )
+            last_line = ltext
+        if ttype not in (tokenize.NEWLINE, tokenize.NL):
+            last_ttext = ttext
+        yield tokenize.TokenInfo(ttype, ttext, (slineno, scol), (elineno, ecol), ltext)
+        last_lineno = elineno
+
+
+def find_soft_key_lines(source: str) -> set[TLineNo]:
+    """Helper for finding lines with soft keywords, like match/case lines."""
+    soft_key_lines: set[TLineNo] = set()
+
+    for node in ast.walk(ast.parse(source)):
+        if sys.version_info >= (3, 10) and isinstance(node, ast.Match):
+            soft_key_lines.add(node.lineno)
+            for case in node.cases:
+                soft_key_lines.add(case.pattern.lineno)
+        elif sys.version_info >= (3, 12) and isinstance(node, ast.TypeAlias):
+            soft_key_lines.add(node.lineno)
+
+    return soft_key_lines
+
+
+def source_token_lines(source: str) -> TSourceTokenLines:
+    """Generate a series of lines, one for each line in `source`.
+
+    Each line is a list of pairs, each pair is a token::
+
+        [('key', 'def'), ('ws', ' '), ('nam', 'hello'), ('op', '('), ... ]
+
+    Each pair has a token class, and the token text.
+
+    If you concatenate all the token texts, and then join them with newlines,
+    you should have your original `source` back, with two differences:
+    trailing white space is not preserved, and a final line with no newline
+    is indistinguishable from a final line with a newline.
+
+    """
+
+    ws_tokens = {token.INDENT, token.DEDENT, token.NEWLINE, tokenize.NL}
+    line: list[tuple[str, str]] = []
+    col = 0
+
+    source = source.expandtabs(8).replace("\r\n", "\n")
+    tokgen = generate_tokens(source)
+
+    if env.PYBEHAVIOR.soft_keywords:
+        soft_key_lines = find_soft_key_lines(source)
+    else:
+        soft_key_lines = set()
+
+    for ttype, ttext, (sline, scol), (_, ecol), _ in _phys_tokens(tokgen):
+        mark_start = True
+        for part in re.split("(\n)", ttext):
+            if part == "\n":
+                yield line
+                line = []
+                col = 0
+                mark_end = False
+            elif part == "":
+                mark_end = False
+            elif ttype in ws_tokens:
+                mark_end = False
+            else:
+                if env.PYBEHAVIOR.fstring_syntax and ttype == token.FSTRING_MIDDLE:
+                    part = part.replace("{", "{{").replace("}", "}}")
+                    ecol = scol + len(part)
+                if mark_start and scol > col:
+                    line.append(("ws", " " * (scol - col)))
+                    mark_start = False
+                tok_class = tokenize.tok_name.get(ttype, "xx").lower()[:3]
+                if ttype == token.NAME:
+                    if keyword.iskeyword(ttext):
+                        # Hard keywords are always keywords.
+                        tok_class = "key"
+                    elif env.PYBEHAVIOR.soft_keywords and keyword.issoftkeyword(ttext):
+                        # Soft keywords appear at the start of their line.
+                        if len(line) == 0:
+                            is_start_of_line = True
+                        elif (len(line) == 1) and line[0][0] == "ws":
+                            is_start_of_line = True
+                        else:
+                            is_start_of_line = False
+                        if is_start_of_line and sline in soft_key_lines:
+                            tok_class = "key"
+                line.append((tok_class, part))
+                mark_end = True
+            scol = 0
+        if mark_end:
+            col = ecol
+
+    if line:
+        yield line
+
+
+def generate_tokens(text: str) -> TokenInfos:
+    """A helper around `tokenize.generate_tokens`.
+
+    Originally this was used to cache the results, but it didn't seem to make
+    reporting go faster, and caused issues with using too much memory.
+
+    """
+    readline = io.StringIO(text).readline
+    return tokenize.generate_tokens(readline)
+
+
+def source_encoding(source: bytes) -> str:
+    """Determine the encoding for `source`, according to PEP 263.
+
+    `source` is a byte string: the text of the program.
+
+    Returns a string, the name of the encoding.
+
+    """
+    readline = iter(source.splitlines(True)).__next__
+    return tokenize.detect_encoding(readline)[0]