This cleans up the API in general, removing a bunch of deprecated stuff,
cleaning up circular imports, etc.
But the biggest change is switching to an optional XML format for the
regex lexer.
Having lexers defined only in Go is not ideal for a couple of reasons.
Firstly, it impedes a significant portion of contributors who use Chroma
in Hugo, but don't know Go. Secondly, it bloats the binary size of any
project that imports Chroma.
Why XML? YAML is an abomination and JSON is not human editable. XML
also compresses very well (eg. Go template lexer XML compresses from
3239 bytes to 718).
Why a new syntax format? All major existing formats rely on the
Oniguruma regex engine, which is extremely complex and for which there
is no Go port.
Why not earlier? Prior to the existence of fs.FS this was not a viable
option.
Benchmarks:
$ hyperfine --warmup 3 \
'./chroma.master --version' \
'./chroma.xml-pre-opt --version' \
'./chroma.xml --version'
Benchmark 1: ./chroma.master --version
Time (mean ± σ): 5.3 ms ± 0.5 ms [User: 3.6 ms, System: 1.4 ms]
Range (min … max): 4.2 ms … 6.6 ms 233 runs
Benchmark 2: ./chroma.xml-pre-opt --version
Time (mean ± σ): 50.6 ms ± 0.5 ms [User: 52.4 ms, System: 3.6 ms]
Range (min … max): 49.2 ms … 51.5 ms 51 runs
Benchmark 3: ./chroma.xml --version
Time (mean ± σ): 6.9 ms ± 1.1 ms [User: 5.1 ms, System: 1.5 ms]
Range (min … max): 5.7 ms … 19.9 ms 196 runs
Summary
'./chroma.master --version' ran
1.30 ± 0.23 times faster than './chroma.xml --version'
9.56 ± 0.83 times faster than './chroma.xml-pre-opt --version'
A slight increase in init time, but I think this is okay given the
increase in flexibility.
And binary size difference:
$ du -h lexers.test*
$ du -sh chroma* 951371ms
8.8M chroma.master
7.8M chroma.xml
7.8M chroma.xml-pre-opt
Benchmarks:
$ hyperfine --warmup 3 \
'./chroma.master --version' \
'./chroma.xml-pre-opt --version' \
'./chroma.xml --version'
Benchmark 1: ./chroma.master --version
Time (mean ± σ): 5.3 ms ± 0.5 ms [User: 3.6 ms, System: 1.4 ms]
Range (min … max): 4.2 ms … 6.6 ms 233 runs
Benchmark 2: ./chroma.xml-pre-opt --version
Time (mean ± σ): 50.6 ms ± 0.5 ms [User: 52.4 ms, System: 3.6 ms]
Range (min … max): 49.2 ms … 51.5 ms 51 runs
Benchmark 3: ./chroma.xml --version
Time (mean ± σ): 6.9 ms ± 1.1 ms [User: 5.1 ms, System: 1.5 ms]
Range (min … max): 5.7 ms … 19.9 ms 196 runs
Summary
'./chroma.master --version' ran
1.30 ± 0.23 times faster than './chroma.xml --version'
9.56 ± 0.83 times faster than './chroma.xml-pre-opt --version'
Incompatible changes:
- (*RegexLexer).SetAnalyser: changed from func(func(text string) float32) *RegexLexer to func(func(text string) float32) Lexer
- (*TokenType).UnmarshalJSON: removed
- Lexer.AnalyseText: added
- Lexer.SetAnalyser: added
- Lexer.SetRegistry: added
- MustNewLazyLexer: removed
- MustNewLexer: changed from func(*Config, Rules) *RegexLexer to func(*Config, func() Rules) *RegexLexer
- Mutators: changed from func(...Mutator) MutatorFunc to func(...Mutator) Mutator
- NewLazyLexer: removed
- NewLexer: changed from func(*Config, Rules) (*RegexLexer, error) to func(*Config, func() Rules) (*RegexLexer, error)
- Pop: changed from func(int) MutatorFunc to func(int) Mutator
- Push: changed from func(...string) MutatorFunc to func(...string) Mutator
- TokenType.MarshalJSON: removed
- Using: changed from func(Lexer) Emitter to func(string) Emitter
- UsingByGroup: changed from func(func(string) Lexer, int, int, ...Emitter) Emitter to func(int, int, ...Emitter) Emitter
Green and red are the de facto colors used to represent inserted and
deleted lines. This changes the red that was already used for deleted to
use the official Dracula red, getting rid of an unofficial color, and
changes the inserted color from foreground white to green, to make
insertions stand out from headings and such.
'l' in gl is for under(l)ine, as the "gu" class is taken by
GenericSubheading.
- Rules for GenericUnderline are added to all the styles
- Make "Underline" style insert "text-decoration: underline" in CSS.
Fixes https://github.com/alecthomas/chroma/issues/159.
- Styles now use a builder system, to enforce immutability of styles.
- Corrected and cleaned up how style inheritance works.
- Added a brightening function to colours
- HTML formatter will now automatically pick line and highlight colours
if they are not provided in the style. This is done by slightly
darkening or lightening.
Fixes#21.
