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fix(bash): keep heredoc continuations highlighted #4415

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2 changes: 2 additions & 0 deletions CHANGES.md
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Original file line number Diff line number Diff line change
Expand Up @@ -17,6 +17,7 @@ New Grammars:

Core Grammars:

- fix(bash) keep heredoc continuation commands outside the string span, issue #4377 [puneetdixit200][]
- fix(javascript) correctly highlight 'for await' again [wolfgang42][]
- enh(csp) add missing directives / keywords from MDN (7 more) [Max Liashuk][]
- enh(ada) add new `parallel` keyword, allow `[]` for Ada 2022 [Max Reznik][]
Expand Down Expand Up @@ -55,6 +56,7 @@ CONTRIBUTORS
[te-ing]: https://github.com/te-ing
[Anthony Martin]: https://github.com/anthony-c-martin
[NriotHrreion]: https://github.com/NriotHrreion
[puneetdixit200]: https://github.com/puneetdixit200


## Version 11.11.1
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71 changes: 47 additions & 24 deletions src/languages/bash.js
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Original file line number Diff line number Diff line change
Expand Up @@ -50,16 +50,6 @@ export default function(hljs) {
}
}
);
const HERE_DOC = {
begin: /<<-?\s*(?=\w+)/,
starts: { contains: [
hljs.END_SAME_AS_BEGIN({
begin: /(\w+)/,
end: /(\w+)/,
className: 'string'
})
] }
};
const QUOTE_STRING = {
className: 'string',
begin: /"/,
Expand Down Expand Up @@ -368,27 +358,60 @@ export default function(hljs) {
"whoami",
"yes"
];
const BASH_KEYWORDS = {
$pattern: /\b[a-z][a-z0-9._-]+\b/,
keyword: KEYWORDS,
literal: LITERALS,
built_in: [
...SHELL_BUILT_INS,
...BASH_BUILT_INS,
// Shell modifiers
"set",
"shopt",
...ZSH_BUILT_INS,
...GNU_CORE_UTILS
]
};
let heredocDelimiter = "";
const HERE_DOC_BODY = {
className: 'string',
begin: /\n/,
end: /^\t*(\w+)$/m,

@joshgoebel joshgoebel Jul 6, 2026

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What is the requirement for heredoc naming in Bash? Could this be tightened up any further than \w+?

@arturict arturict Jul 12, 2026

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I think this needs broadening rather than tightening. Bash takes a word after << and applies quote removal; it is not limited to \w+.

For example, this branch captures only END here and never finds the real terminator, so echo done stays inside the string:

cat <<END-OF | cat
hello
END-OF
echo done

<<'EOF' is valid too, but is not recognized as a heredoc by this matcher. Could we add both as markup cases before settling on the delimiter match?

@joshgoebel joshgoebel Jul 13, 2026

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Sure. Add all the cases we know of, then try to get the highlighted correctly - that's the way to do it.

endsParent: true,
'on:end': (m, resp) => {
if (m[1] !== heredocDelimiter) resp.ignoreMatch();
}
};
const HERE_DOC = {
begin: /<<-?\s*(\w+)/,
'on:begin': (m) => { heredocDelimiter = m[1]; },
end: /\n/,
returnEnd: true,
keywords: BASH_KEYWORDS,
contains: [
ARITHMETIC,
COMMENT,
PATH_MODE,
QUOTE_STRING,
ESCAPED_QUOTE,
APOS_STRING,
ESCAPED_APOS,
VAR
Comment on lines +391 to +399

@joshgoebel joshgoebel Jul 6, 2026

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All of this is because of the pipe and piping the string into any sequence of bash, right?

@arturict arturict Jul 12, 2026

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Not only pipes. The same split is needed for any shell syntax after the delimiter word, for example <<EOF >out or <<EOF && echo queued. The body should start at the following newline; everything before that newline should remain normal Bash.

],
starts: {
contains: [
HERE_DOC_BODY
]
}
};

return {
name: 'Bash',
aliases: [
'sh',
'zsh'
],
keywords: {
$pattern: /\b[a-z][a-z0-9._-]+\b/,
keyword: KEYWORDS,
literal: LITERALS,
built_in: [
...SHELL_BUILT_INS,
...BASH_BUILT_INS,
// Shell modifiers
"set",
"shopt",
...ZSH_BUILT_INS,
...GNU_CORE_UTILS
]
},
keywords: BASH_KEYWORDS,
contains: [
KNOWN_SHEBANG, // to catch known shells and boost relevancy
hljs.SHEBANG(), // to catch unknown shells but still highlight the shebang
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3 changes: 3 additions & 0 deletions test/markup/bash/heredoc-continuation.expect.txt
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@@ -0,0 +1,3 @@
<span class="hljs-built_in">echo</span> <span class="hljs-string">&quot;ok&quot;</span> &lt;&lt;-EOF | <span class="hljs-built_in">cat</span><span class="hljs-string">
Hello
EOF</span>
3 changes: 3 additions & 0 deletions test/markup/bash/heredoc-continuation.txt
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@@ -0,0 +1,3 @@
echo "ok" <<-EOF | cat
Hello
EOF
2 changes: 1 addition & 1 deletion test/markup/bash/strings.expect.txt
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Expand Up @@ -2,7 +2,7 @@ SCRIPT_DIR=<span class="hljs-string">&quot;<span class="hljs-subst">$( cd <span
TLS_DIR=<span class="hljs-string">&quot;<span class="hljs-variable">$SCRIPT_DIR</span>/../src/main/resources/tls&quot;</span>
ROOT_DIR=<span class="hljs-string">&quot;<span class="hljs-variable">$SCRIPT_DIR</span>/..&quot;</span>

jshell -s - &lt;&lt; <span class="hljs-string">EOF
jshell -s - &lt;&lt; EOF<span class="hljs-string">
System.out.printf(&quot;Procs: %s%n&quot;, getdata())
EOF</span>

Expand Down