fix(@angular/build): support standard JavaScript MIME types and case insensitivity in auto-CSP - #34114
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…insensitivity in auto-CSP Previously, isJavascriptMimeType() in auto-csp.ts only performed a case-sensitive check against 'text/javascript' on the slice prior to the first semicolon. This caused several issues: 1. Valid and common JavaScript MIME types specified in the HTML Living Standard such as application/javascript and text/ecmascript were not recognized as JavaScript. 2. Case differences (e.g. type="text/JavaScript" or type="Module") were not matched, despite HTML attribute matching and MIME types being ASCII case-insensitive. 3. Whitespace around the essence (e.g. type="text/javascript ; charset=utf-8" or type=" text/javascript") caused the strict equality check to fail. When a script tag with one of these valid types was not recognized, auto-csp bypassed dynamic script rewriting and emitted the script element as-is into index.html. Under the generated strict CSP, the browser would then block the script from executing. This change introduces JAVASCRIPT_MIME_TYPES containing all HTML-standard JavaScript MIME types, normalizes the essence (stripping parameters, trimming surrounding whitespace, and lowercasing), and updates shouldDynamicallyLoadScriptTagBasedOnType to support case-insensitive module types.
clydin
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September 17, 2026 20:42
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This pull request updates the auto-CSP utility to support all standard JavaScript MIME types according to the HTML specification, ensuring robust handling of case-insensitivity, parameters, and whitespace. It also adds comprehensive unit tests to validate these changes. There are no review comments, so I have no feedback to provide.
clydin
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target: patch
alan-agius4
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action: merge
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Previously, isJavascriptMimeType() in auto-csp.ts only performed a case-sensitive check against 'text/javascript' on the slice prior to the first semicolon.
This caused several issues:
When a script tag with one of these valid types was not recognized, auto-csp bypassed dynamic script rewriting and emitted the script element as-is into index.html. Under the generated strict CSP, the browser would then block the script from executing.
This change introduces JAVASCRIPT_MIME_TYPES containing all HTML-standard JavaScript MIME types, normalizes the essence (stripping parameters, trimming surrounding whitespace, and lowercasing), and updates shouldDynamicallyLoadScriptTagBasedOnType to support case-insensitive module types.