From 0d3f446460b22a29c259e7d42ed89f90fd216ca7 Mon Sep 17 00:00:00 2001 From: Giteabot Date: Wed, 3 Apr 2024 14:06:39 +0800 Subject: [PATCH] Fixes #27605: inline math blocks can't be preceeded/followed by alphanumerical characters (#30175) (#30250) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Backport #30175 by @jmlt2002 - Inline math blocks couldn't be preceeded or succeeded by alphanumerical characters due to changes introduced in PR #21171. Removed the condition that caused this (precedingCharacter condition) and added a new exit condition of the for-loop that checks if a specific '$' was escaped using '\' so that the math expression can be rendered as intended. - Additionally this PR fixes another bug where math blocks of the type '$xyz$abc$' where the dollar sign was not escaped by the user, generated an error (shown in the screenshots below) - Altered the tests to accomodate for the changes Former behaviour (from try.gitea.io): ![image](https://github.com/go-gitea/gitea/assets/114936010/8f0cbb21-321d-451c-b871-c67a8e1e9235) Fixed behaviour (from my local build): ![image](https://github.com/go-gitea/gitea/assets/114936010/5c22687c-6f11-4407-b5e7-c14b838bc20d) (Edit) Source code for the README.md file: ``` $x$ -$x$ $x$- a$xa$ $xa$a 1$xb$ $xb$1 $a a$b b$ a$b $a a$b b$ $a a\$b b$ ``` Signed-off-by: João Tiago Co-authored-by: João Tiago <114936010+jmlt2002@users.noreply.github.com> (cherry picked from commit 5123ed31914f704348c0660468a3707011f5a160) --- modules/markup/markdown/markdown_test.go | 20 +++++++++++++++++-- modules/markup/markdown/math/inline_parser.go | 18 ++++++++++++----- 2 files changed, 31 insertions(+), 7 deletions(-) diff --git a/modules/markup/markdown/markdown_test.go b/modules/markup/markdown/markdown_test.go index 3cb11c9482..a2285a223a 100644 --- a/modules/markup/markdown/markdown_test.go +++ b/modules/markup/markdown/markdown_test.go @@ -509,9 +509,17 @@ func TestMathBlock(t *testing.T) { `\(a\) \(b\)`, `

a b

` + nl, }, + { + `$a$.`, + `

a.

` + nl, + }, + { + `.$a$`, + `

.$a$

` + nl, + }, { `$a a$b b$`, - `

a a$b b

` + nl, + `

$a a$b b$

` + nl, }, { `a a$b b`, @@ -519,7 +527,15 @@ func TestMathBlock(t *testing.T) { }, { `a$b $a a$b b$`, - `

a$b a a$b b

` + nl, + `

a$b $a a$b b$

` + nl, + }, + { + "a$x$", + `

a$x$

` + nl, + }, + { + "$x$a", + `

$x$a

` + nl, }, { "$$a$$", diff --git a/modules/markup/markdown/math/inline_parser.go b/modules/markup/markdown/math/inline_parser.go index 0ac25c2b2a..862234e69b 100644 --- a/modules/markup/markdown/math/inline_parser.go +++ b/modules/markup/markdown/math/inline_parser.go @@ -41,9 +41,12 @@ func (parser *inlineParser) Trigger() []byte { return parser.start[0:1] } +func isPunctuation(b byte) bool { + return b == '.' || b == '!' || b == '?' || b == ',' || b == ';' || b == ':' +} + func isAlphanumeric(b byte) bool { - // Github only cares about 0-9A-Za-z - return (b >= '0' && b <= '9') || (b >= 'A' && b <= 'Z') || (b >= 'a' && b <= 'z') + return (b >= 'a' && b <= 'z') || (b >= 'A' && b <= 'Z') || (b >= '0' && b <= '9') } // Parse parses the current line and returns a result of parsing. @@ -56,7 +59,7 @@ func (parser *inlineParser) Parse(parent ast.Node, block text.Reader, pc parser. } precedingCharacter := block.PrecendingCharacter() - if precedingCharacter < 256 && isAlphanumeric(byte(precedingCharacter)) { + if precedingCharacter < 256 && (isAlphanumeric(byte(precedingCharacter)) || isPunctuation(byte(precedingCharacter))) { // need to exclude things like `a$` from being considered a start return nil } @@ -75,14 +78,19 @@ func (parser *inlineParser) Parse(parent ast.Node, block text.Reader, pc parser. ender += pos // Now we want to check the character at the end of our parser section - // that is ender + len(parser.end) + // that is ender + len(parser.end) and check if char before ender is '\' pos = ender + len(parser.end) if len(line) <= pos { break } - if !isAlphanumeric(line[pos]) { + suceedingCharacter := line[pos] + if !isPunctuation(suceedingCharacter) && !(suceedingCharacter == ' ') { + return nil + } + if line[ender-1] != '\\' { break } + // move the pointer onwards ender += len(parser.end) }