From 9627921cb29b09f60ad00d7573a4f4f01a91d7dd Mon Sep 17 00:00:00 2001
From: Wilson Lin <code@wilsonl.in>
Date: Sat, 25 Jul 2020 13:22:25 +1000
Subject: [PATCH] Do not minify non-JS script data

---
 bench/README.md    |  2 +-
 src/tests/mod.rs   |  2 ++
 src/unit/script.rs |  4 ++--
 src/unit/tag.rs    | 17 ++++++++++++-----
 4 files changed, 17 insertions(+), 8 deletions(-)

diff --git a/bench/README.md b/bench/README.md
index 75d7571..c70c367 100644
--- a/bench/README.md
+++ b/bench/README.md
@@ -42,7 +42,7 @@ Since speed depends on the input, speed charts show performance relative to the
 The settings used for each minifier can be found in [minifiers.js](./minifiers.js). Some settings to note:
 
 - CSS minification is disabled for all, as minify-html currently does not support CSS minification (coming soon).
-- To increase fairness, all minifiers use esbuild for JS minification, and do so asynchronously and in parallel, similar to how minify-html works.
+- All minifiers are configured to use esbuild for JS minification asynchronously and in parallel, similar to how minify-html works.
 - `conservativeCollapse` is enabled for html-minifier as otherwise some whitespace would be unsafely removed with side affects. minify-html can safely remove whitespace with context if configured properly.
 
 ## Running
diff --git a/src/tests/mod.rs b/src/tests/mod.rs
index 264caaf..e45931a 100644
--- a/src/tests/mod.rs
+++ b/src/tests/mod.rs
@@ -168,6 +168,7 @@ fn test_script_type_attr_value_removal() {
     eval(b"<script type=\"application/ecmascript\"></script>", b"<script></script>");
     eval(b"<script type=\"application/javascript\"></script>", b"<script></script>");
     eval(b"<script type=\"text/jscript\"></script>", b"<script></script>");
+    eval(b"<script type=\"text/plain\"></script>", b"<script type=text/plain></script>");
 }
 
 #[test]
@@ -304,4 +305,5 @@ fn test_js_minification() {
         <script>let a = 1;</script>
         <script>let b = 2;</script>
     "#, b"<script>let a=1;</script><script>let b=2;</script>");
+    eval_with_js_min(b"<script type=text/plain>   alert(1.00000);   </script>", b"<script type=text/plain>   alert(1.00000);   </script>");
 }
diff --git a/src/unit/script.rs b/src/unit/script.rs
index 652681b..c8e32a3 100644
--- a/src/unit/script.rs
+++ b/src/unit/script.rs
@@ -25,7 +25,7 @@ lazy_static! {
     };
 }
 
-pub fn process_script(proc: &mut Processor, cfg: &Cfg) -> ProcessingResult<()> {
+pub fn process_script(proc: &mut Processor, cfg: &Cfg, js: bool) -> ProcessingResult<()> {
     #[cfg(feature = "js-esbuild")]
     let start = Checkpoint::new(proc);
     loop {
@@ -35,7 +35,7 @@ pub fn process_script(proc: &mut Processor, cfg: &Cfg) -> ProcessingResult<()> {
         // `process_tag` will require closing tag.
         if proc.m(IsSeq(b"</script"), MatchOnly).nonempty() {
             #[cfg(feature = "js-esbuild")]
-            if cfg.minify_js {
+            if js && cfg.minify_js {
                 let (wg, results) = proc.new_script_section();
                 let src = start.written_range(proc);
                 // TODO Optimise: Avoid copying to new Vec.
diff --git a/src/unit/tag.rs b/src/unit/tag.rs
index cebf437..974324c 100644
--- a/src/unit/tag.rs
+++ b/src/unit/tag.rs
@@ -42,7 +42,8 @@ lazy_static! {
 
 #[derive(Copy, Clone)]
 enum TagType {
-    Script,
+    ScriptJs,
+    ScriptData,
     Style,
     Other,
 }
@@ -110,8 +111,9 @@ pub fn process_tag(proc: &mut Processor, cfg: &Cfg, ns: Namespace, mut prev_sibl
     // Write previously skipped name and use written code as range (otherwise source code will eventually be overwritten).
     let tag_name = proc.write_range(source_tag_name);
 
-    let tag_type = match &proc[tag_name] {
-        b"script" => TagType::Script,
+    let mut tag_type = match &proc[tag_name] {
+        // Unless non-JS MIME `type` is provided, `script` tags contain JS.
+        b"script" => TagType::ScriptJs,
         b"style" => TagType::Style,
         _ => TagType::Other,
     };
@@ -153,13 +155,17 @@ pub fn process_tag(proc: &mut Processor, cfg: &Cfg, ns: Namespace, mut prev_sibl
 
         let ProcessedAttr { name, typ, value } = process_attr(proc, ns, tag_name)?;
         match (tag_type, &proc[name]) {
-            (TagType::Script, b"type") => {
+            // NOTE: We don't support multiple `type` attributes, so can't go from ScriptData => ScriptJs.
+            (TagType::ScriptJs, b"type") => {
                 // It's JS if the value is empty or one of `JAVASCRIPT_MIME_TYPES`.
                 let script_tag_type_is_js = value
                     .filter(|v| !JAVASCRIPT_MIME_TYPES.contains(&proc[*v]))
                     .is_none();
                 if script_tag_type_is_js {
                     erase_attr = true;
+                } else {
+                    // Tag does not contain JS, don't minify JS.
+                    tag_type = TagType::ScriptData;
                 };
             }
             (_, name) => {
@@ -203,7 +209,8 @@ pub fn process_tag(proc: &mut Processor, cfg: &Cfg, ns: Namespace, mut prev_sibl
     };
 
     match tag_type {
-        TagType::Script => process_script(proc, cfg)?,
+        TagType::ScriptData => process_script(proc, cfg, false)?,
+        TagType::ScriptJs => process_script(proc, cfg, true)?,
         TagType::Style => process_style(proc)?,
         _ => process_content(proc, cfg, child_ns, Some(tag_name))?,
     };