fix: read content encoding hints from <meta> tags#3780
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janbuchar
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Jun 30, 2026
| */ | ||
| export function extractCharsetFromHtmlBytes(bytes: Buffer): string | undefined { | ||
| // latin1 preserves byte values for ASCII-compatible encodings, making the meta tags readable | ||
| const prescan = bytes.subarray(0, 1024).toString('latin1'); |
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Are you sure that 1024 bytes will do it?
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See 13.2.3.2 Determining the character encoding paragraph 5:
Optionally, prescan the byte stream to determine its encoding, with the end condition being when the user agent decides that scanning further bytes would not be efficient. User agents are encouraged to only prescan the first 1024 bytes. User agents may decide that scanning any bytes is not efficient, in which case these substeps are entirely skipped.
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Okay, lawyered. Approving.
janbuchar
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Jun 30, 2026
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barjin
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Jul 20, 2026
Utilizes the byte-stream prescan (https://html.spec.whatwg.org/multipage/parsing.html#prescan-a-byte-stream-to-determine-its-encoding) to determine the HTML document encoding, if not specified in HTTP headers (or explicitly forced by user). Closes #2317
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Utilizes the byte-stream prescan (https://html.spec.whatwg.org/multipage/parsing.html#prescan-a-byte-stream-to-determine-its-encoding) to determine the HTML document encoding, if not specified in HTTP headers (or explicitly forced by user).
Closes #2317