Don't highlight code spans in headers. (rust-lang#1162)

src/theme/book.js

@@ -143,6 +143,11 @@ function playpen_text(playpen) {
         languages: [],      // Languages used for auto-detection
     });
 
+    let code_nodes = Array
+        .from(document.querySelectorAll('code'))
+        // Don't highlight `inline code` blocks in headers.
+        .filter(function (node) {return !node.parentElement.classList.contains("header"); });
+
     if (window.ace) {
         // language-rust class needs to be removed for editable
         // blocks or highlightjs will capture events
@@ -154,16 +159,12 @@ function playpen_text(playpen) {
             .from(document.querySelectorAll('code:not(.editable)'))
             .forEach(function (block) { hljs.highlightBlock(block); });
     } else {
-        Array
-            .from(document.querySelectorAll('code'))
-            .forEach(function (block) { hljs.highlightBlock(block); });
+        code_nodes.forEach(function (block) { hljs.highlightBlock(block); });
     }
 
     // Adding the hljs class gives code blocks the color css
     // even if highlighting doesn't apply
-    Array
-        .from(document.querySelectorAll('code'))
-        .forEach(function (block) { block.classList.add('hljs'); });
+    code_nodes.forEach(function (block) { block.classList.add('hljs'); });
 
     Array.from(document.querySelectorAll("code.language-rust")).forEach(function (block) {
 

src/theme/css/general.css

@@ -25,6 +25,11 @@ code {
     font-size: 0.875em; /* please adjust the ace font size accordingly in editor.js */
 }
 
+/* Don't change font size in headers. */
+h1 code, h2 code, h3 code, h4 code, h5 code, h6 code {
+    font-size: unset;
+}
+
 .left { float: left; }
 .right { float: right; }
 .boring { opacity: 0.6; }