diff options
Diffstat (limited to 'third_party/pycoverage/coverage/phystokens.py')
| -rw-r--r-- | third_party/pycoverage/coverage/phystokens.py | 210 |
1 files changed, 210 insertions, 0 deletions
diff --git a/third_party/pycoverage/coverage/phystokens.py b/third_party/pycoverage/coverage/phystokens.py new file mode 100644 index 0000000..99b1d5b --- /dev/null +++ b/third_party/pycoverage/coverage/phystokens.py @@ -0,0 +1,210 @@ +"""Better tokenizing for coverage.py.""" + +import codecs, keyword, re, sys, token, tokenize +from coverage.backward import set # pylint: disable=W0622 +from coverage.parser import generate_tokens + + +def phys_tokens(toks): + """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 = None + last_lineno = -1 + last_ttype = None + 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_ttype == tokenize.COMMENT: + # Comments like this \ + # should never result in a new token. + inject_backslash = False + elif ttype == token.STRING: + if "\n" in ttext and ttext.split('\n', 1)[0][-1] == '\\': + # It's a multiline string and the first line ends with + # a backslash, so we don't need to inject another. + 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 ( + 99999, "\\\n", + (slineno, ccol), (slineno, ccol+2), + last_line + ) + last_line = ltext + last_ttype = ttype + yield ttype, ttext, (slineno, scol), (elineno, ecol), ltext + last_lineno = elineno + + +def source_token_lines(source): + """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 whitespace is not preserved, and a final line with no newline + is indistinguishable from a final line with a newline. + + """ + ws_tokens = set([token.INDENT, token.DEDENT, token.NEWLINE, tokenize.NL]) + line = [] + col = 0 + source = source.expandtabs(8).replace('\r\n', '\n') + tokgen = generate_tokens(source) + for ttype, ttext, (_, 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 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 and keyword.iskeyword(ttext): + tok_class = "key" + line.append((tok_class, part)) + mark_end = True + scol = 0 + if mark_end: + col = ecol + + if line: + yield line + +def source_encoding(source): + """Determine the encoding for `source` (a string), according to PEP 263. + + Returns a string, the name of the encoding. + + """ + # Note: this function should never be called on Python 3, since py3 has + # built-in tools to do this. + assert sys.version_info < (3, 0) + + # This is mostly code adapted from Py3.2's tokenize module. + + cookie_re = re.compile(r"coding[:=]\s*([-\w.]+)") + + # Do this so the detect_encode code we copied will work. + readline = iter(source.splitlines(True)).next + + def _get_normal_name(orig_enc): + """Imitates get_normal_name in tokenizer.c.""" + # Only care about the first 12 characters. + enc = orig_enc[:12].lower().replace("_", "-") + if re.match(r"^utf-8($|-)", enc): + return "utf-8" + if re.match(r"^(latin-1|iso-8859-1|iso-latin-1)($|-)", enc): + return "iso-8859-1" + return orig_enc + + # From detect_encode(): + # It detects the encoding from the presence of a utf-8 bom or an encoding + # cookie as specified in pep-0263. If both a bom and a cookie are present, + # but disagree, a SyntaxError will be raised. If the encoding cookie is an + # invalid charset, raise a SyntaxError. Note that if a utf-8 bom is found, + # 'utf-8-sig' is returned. + + # If no encoding is specified, then the default will be returned. The + # default varied with version. + + if sys.version_info <= (2, 4): + default = 'iso-8859-1' + else: + default = 'ascii' + + bom_found = False + encoding = None + + def read_or_stop(): + """Get the next source line, or ''.""" + try: + return readline() + except StopIteration: + return '' + + def find_cookie(line): + """Find an encoding cookie in `line`.""" + try: + line_string = line.decode('ascii') + except UnicodeDecodeError: + return None + + matches = cookie_re.findall(line_string) + if not matches: + return None + encoding = _get_normal_name(matches[0]) + try: + codec = codecs.lookup(encoding) + except LookupError: + # This behaviour mimics the Python interpreter + raise SyntaxError("unknown encoding: " + encoding) + + if bom_found: + # codecs in 2.3 were raw tuples of functions, assume the best. + codec_name = getattr(codec, 'name', encoding) + if codec_name != 'utf-8': + # This behaviour mimics the Python interpreter + raise SyntaxError('encoding problem: utf-8') + encoding += '-sig' + return encoding + + first = read_or_stop() + if first.startswith(codecs.BOM_UTF8): + bom_found = True + first = first[3:] + default = 'utf-8-sig' + if not first: + return default + + encoding = find_cookie(first) + if encoding: + return encoding + + second = read_or_stop() + if not second: + return default + + encoding = find_cookie(second) + if encoding: + return encoding + + return default |