Preserve attributes on HTML paragraphs #10850
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Thanks for this. As noted I didn't understand the special treatment of "align".
Another question I have is how common it is for paragraphs to have classes or other attributes in HTML in the wild. If it is very common, then I suppose this change will lead to more cluttered HTML -> markdown conversions and we'd need to weight that.
src/Text/Pandoc/Readers/HTML.hs
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| pParaWithWrapper :: PandocMonad m => Attr -> TagParser m Blocks | ||
| pParaWithWrapper (ident, classes, kvs) = do | ||
| guardEnabled Ext_native_divs -- Ensure native_divs is enabled for this behavior | ||
| pInhalt <- trimInlines <$> pInTags "p" inline |
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I usually use the naming convention of beginning parsers with p; so it would be better to use something like inhalt instead for this name.
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Good point! I've renamed it to contents to follow your p prefix convention for parsers. Thanks for catching that!
src/Text/Pandoc/Readers/HTML.hs
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| let otherKVs = filter (\(k,_) -> k /= "align") kvs | ||
| let validAlignKV = case alignValue of | ||
| Just algn | algn `elem` ["left","right","center","justify"] -> [("align", algn)] | ||
| _ -> [] | ||
| let finalKVs = wrapperAttr : (validAlignKV ++ otherKVs) |
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What is the motivation for treating the "align" attribute specially in this way?
src/Text/Pandoc/Readers/HTML.hs
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| return (case alignValue of | ||
| Just algn | algn `elem` ["left","right","center","justify"] -> | ||
| B.divWith ("", [], [("align", algn)]) paraBlock |
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I don't understand the motivation for this.
- HTML reader wraps attributed `p` tags in `Div` with `wrapper="1"`. - HTML writer unwraps `Div` with `wrapper="1"` back to attributed `p` tag. - Add tests for HTML paragraph attribute roundtrip. - Update EPUB golden files to reflect new AST for attributed paragraphs.
Split pPara into pParaWithWrapper and pParaSimple helpers. Ensure pParaWithWrapper correctly discards invalid align attributes. Add specific tests for align attribute in HTML reader and writer.
- Update MANUAL.txt to reflect `native_divs` wrapping of attributed `<p>` tags.
- Add test cases for HTML to native, native to HTML, HTML to HTML, and HTML to HTML5 conversions - Verify preservation of id, class, and data attributes on p tags
- Treat align attribute like any other attribute - Always wrap paragraphs with attributes in divs (including align-only) - Remove validation logic for align values - Update tests to reflect consistent wrapper behavior
Thanks for catching that! You're right about the align logic - that was actually an idea I had initially discarded, but it seems to have somehow made its way into the pull request anyway. I'll remove that special handling. Regarding your question about paragraph attributes in the wild - you're absolutely right to be concerned. Paragraphs with classes and other attributes are extremely common in modern HTML, especially with:
A configurable approach would be ideal here. We could add a command-line option or extension setting that controls attribute preservation behavior:
This would allow users to choose between clean output (which most expect from HTML→Markdown conversion) and technical preservation (needed for specific use cases like documentation sites requiring anchor links). The majority of conversions prioritize readability over technical fidelity, so defaulting to clean output while providing flexibility makes the most sense. |
This PR implements the preservation of attributes on HTML paragraphs, addressing issue #10768.
HTML reader now wraps attributed <p> tags in a Div with wrapper="1".
HTML writer unwraps these Divs back to attributed <p> tags.
This approach is similar to the Djot reader/writer as discussed in #10768, ensuring that semantic information in HTML attributes on paragraphs is preserved during conversion.