matrix/weechat-matrix
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Fix handling of backslashes in relation to code blocks (#203)

Browse source 
Backslashes are now correctly preserved inside code blocks while still allowing the user to escape a backtick. The handling of backticks and bold/italic wrappers was unified so that they share the same escaping code.

Backslashes only escape Markdown wrapper characters (*, _, `). If they are encountered before another character, they are considered literal.
This commit is contained in:
Tom Smeding 2020-06-03 13:06:16 +02:00 committed by GitHub
parent 3cf5cc077e
commit a5e6434c31
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
2 changed files with 60 additions and 31 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

81
matrix/colors.py
View file

@ -88,23 +88,44 @@ class Formatted(object):
substrings = [] # type: List[FormattedString]
attributes = DEFAULT_ATTRIBUTES.copy()
def last_match_index(regex, subject, offset_in_match):
matches = list(re.finditer(regex, subject))
# Escaped things are not markdown delimiters, so substitute them away
# when (quickly) looking for the last delimiters in the line. Note that
# the replacement needs to be the same length as the original for the
# indices to be correct.
escaped_masked = re.sub(r"\\[\\*_`]", "aa", line)
def last_match_index(regex, offset_in_match):
matches = list(re.finditer(regex, escaped_masked))
return matches[-1].span()[0] + offset_in_match if matches else -1
# 'needs_word': whether the wrapper must surround words, for example
# '*italic*' and not '* not-italic *'.
# 'validate': whether it can occur within the current attributes
wrappers = {
"**": {
"key": "bold",
"last_index": last_match_index(r"\S\*\*", line, 1),
"last_index": last_match_index(r"\S\*\*", 1),
"needs_word": True,
"validate": lambda attrs: not attrs["code"],
},
"*": {
"key": "italic",
"last_index": last_match_index(r"\S\*($|[^*])", line, 1),
"last_index": last_match_index(r"\S\*($|[^*])", 1),
"needs_word": True,
"validate": lambda attrs: not attrs["code"],
},
"_": {
"key": "italic",
"last_index": last_match_index(r"\S_", line, 1),
"last_index": last_match_index(r"\S_", 1),
"needs_word": True,
"validate": lambda attrs: not attrs["code"],
},
"`": {
"key": "code",
"last_index": last_match_index(r"`", 0),
"needs_word": False,
"validate": lambda attrs: True,
}
}
wrapper_init_chars = set(k[0] for k in wrappers.keys())
wrapper_max_len = max(len(k) for k in wrappers.keys())
@ -115,14 +136,17 @@ class Formatted(object):
"\x1F": "underline",
}
last_backtick = line.rfind("`")
# Characters that consume a prefixed backslash
escapable_chars = wrapper_init_chars.copy()
escapable_chars.add("\\")
i = 0
while i < len(line):
# Markdown escape
# NOTE: IRC-native formatting characters are not escaped
if i + 1 < len(line) and line[i] == "\\" \
and line[i + 1] not in "\x02\x03\x0F\x1D\x1F":
and (line[i + 1] in escapable_chars
if not attributes["code"]
else line[i + 1] == "`"):
text += line[i + 1]
i = i + 2
@ -183,32 +207,26 @@ class Formatted(object):
else:
attributes["bgcolor"] = None
# Markdown inline code
elif line[i] == "`" and (attributes["code"] or last_backtick > i):
if text:
# strip leading and trailing spaces and compress consecutive
# spaces in inline code blocks
if attributes["code"]:
text = text.strip()
text = re.sub(r"\s+", " ", text)
substrings.append(
FormattedString(text, attributes.copy())
)
text = ""
attributes["code"] = not attributes["code"]
i = i + 1
# Markdown wrapper (emphasis/bold)
elif line[i] in wrapper_init_chars and not attributes["code"]:
# Markdown wrapper (emphasis/bold/code)
elif line[i] in wrapper_init_chars:
for l in range(wrapper_max_len, 0, -1):
if i + l <= len(line) and line[i : i + l] in wrappers:
descriptor = wrappers[line[i : i + l]]
if not descriptor["validate"](attributes):
continue
if attributes[descriptor["key"]]:
# Can only turn off if preceded by non-whitespace
if not line[i - 1].isspace():
# needs_word wrappers can only be turned off if
# preceded by non-whitespace
if (i >= 1 and not line[i - 1].isspace()) \
or not descriptor["needs_word"]:
if text:
# strip leading and trailing spaces and
# compress consecutive spaces in inline
# code blocks
if descriptor["key"] == "code":
text = re.sub(r"\s+", " ", text.strip())
substrings.append(
FormattedString(text, attributes.copy()))
text = ""
@ -218,10 +236,11 @@ class Formatted(object):
text = text + line[i : i + l]
i = i + l
# Must have a chance of closing this, and be followed
# by non-whitespace
# Must have a chance of closing this, and needs_word
# wrappers must be followed by non-whitespace
elif descriptor["last_index"] >= i + l and \
not line[i + l].isspace():
(not line[i + l].isspace() or \
not descriptor["needs_word"]):
if text:
substrings.append(
FormattedString(text, attributes.copy()))

10
tests/color_test.py
View file

@ -109,6 +109,16 @@ def test_input_line_markdown_various2():
assert "norm** <code>code **code *code</code> norm `norm" \
== formatted.to_html()
def test_input_line_backslash():
def convert(s): return Formatted.from_input_line(s).to_html()
assert "pre <em>italic* ital</em> norm" == convert("pre *italic\\* ital* norm")
assert "*norm* norm" == convert("\\*norm* norm")
assert "<em>*ital</em>" == convert("*\\*ital*")
assert "<code>C:\\path</code>" == convert("`C:\\path`")
assert "<code>with`tick</code>" == convert("`with\\`tick`")
assert "`un`matched" == convert("`un\\`matched")
assert "<strong>bold </strong><em><strong>*bital</strong></em> norm" == convert("**bold *\\*bital*** norm")
def test_conversion():
formatted = Formatted.from_input_line("*Hello*")
formatted2 = Formatted.from_html(formatted.to_html())