jgm/pandoc: pandoc 2.16

Click to expand changelog - Switch back from HsYAML to yaml for parsing YAML metadata (#6084). HsYAML is around 20 times slower in parsing large YAML bibliographies. In addition, HsYAML is not being actively maintained. This sets us back in our attempts to free ourselves from C dependencies (#4535). But I don't see a good alternative until a faster pure Haskell parser is available. Notes: - We've removed the FromYAML instances for all types that had them, since this is a HsYAML-specific typeclass \[API change\]. (The yaml package just uses From/ToJSON instead of having a dedicated From/ToYAML class.) - Unlike HsYAML (in the configuration we were using), yaml parses 'Y', 'N', 'Yes', 'No', 'On', 'Off' as boolean values. Users may need to quote these when they are meant to be interpreted as strings. Similarly, 'null' is parsed as a YAML null value (and will be treated as an empty string by pandoc rather than the string 'null'). Quoting it will force it to be interpreted as a string. - Some tests had to be adjusted accordingly. - Pandoc now behaves in a more useful way when the YAML metadata contains escaping errors: instead of just failng silently and falling back to some other interpretation of the section, it raises a YAML parsing error. - Markdown writer: Ensure that special values are quoted in YAML metadata. These include "Y", "yes", "on", and "off", which are now (with yaml library) considered boolean values, as well as "null". - Change JSON encodings of some types. - For LineEnding use lowercase constructors, e.g. `crlf`, `native`. - For HTMLSlideVariant use lowercase constructors. - For ReaderOptions use e.g. `default-image-extension` instead of `readerDefaultImageExtension` for field names. - For Extension, use e.g. `tex_math_dollars` instead of `Ext_tex_math_dollars` as constructor. - For Extensions, use an array of Extensions, instead of an object wrapping the tag `Extensions` and an integer. (The integer representation is not supposed to be part of the public API.) - For Opt, use field names like `tab-stop` instead of `optTabStop`. - Docx writer: - Add IDs to native_numbering test (Tristan Stenner). - Move ":" out of the caption bookmark (Tristan Stenner). This is needed so that native references to the figure are included as "As seen in Figure X, it is…" instead of "As seen in \[Figure: X, it is…" - Lua (Albert Krewinkel, except as noted): - Use hslua module abstraction where possible. - Fix placement of tests for Block elements in pandoc module tests - Increase strictness when getting attribute keys - Re-add `t` and `tag` property to Attr values. Removal of these properties from Attr values was a regression. - Fix `pandoc.utils.stringify` regression. The `pandoc.utils.stringify` function returned empty strings when called with a string argument. - Fix a copy/paste bug in Lua marshalling code (John MacFarlane, #7639). This caused links to be changed to figures when Lua filters changed link properties. - Re-add `content` property to Link elements (#7647). This was a regression introduced in version 2.15. - Generate constants in module pandoc programmatically. - Marshal SimpleTable, ListAttributes, Citation, and Block values as userdata objects. Properties of Block values are marshalled lazily, which generally improves performance considerably. Script users may also notice the following differences: - Block element properties can no longer be accessed by numerical indexing of the `.c` field. The `.c` property now serves as an alias for `.content`, so some filter that used this undocumented method for property access may continue to work, while others will need to be updated and use proper property names. - The marshalled Block elements now have a `show` method, and a `__tostring` metamethod. Both return the Haskell string representation of the element. - Block values now have the Lua type `userdata` instead of `table`. - Add a short guide to pandoc's sources (Albert Krewinkel). - Fix epub files in epub reader tests, so that they are valid according to epubcheck (#7586). - Allow time 1.13. - Require latest skylighting (0.12.1). - Fix build on GHC 9.2 (Joseph C. Sible). - Fix trypandoc so it builds with aeson \> 2.