lexers

README

Lexer tests

The tests in this directory feed a known input testdata/<name>.actual into the parser for <name> and check that its output matches <name>.exported.

It is also possible to perform several tests on a same parser <name>, by placing know inputs *.actual into a directory testdata/<name>/.

Running the tests

Run the tests as normal:

go test ./lexers

Update existing tests

When you add a new test data file (*.actual), you need to regenerate all tests. That's how Chroma creates the *.expected test file based on the corresponding lexer.

To regenerate all tests, type in your terminal:

RECORD=true go test ./lexers

This first sets the RECORD environment variable to true. Then it runs go test on the ./lexers directory of the Chroma project.

(That environment variable tells Chroma it needs to output test data. After running go test ./lexers you can remove or reset that variable.)

Windows users

Windows users will find that the RECORD=true go test ./lexers command fails in both the standard command prompt terminal and in PowerShell.

Instead we have to perform both steps separately:

• Set the RECORD environment variable to true.
  • In the regular command prompt window, the set command sets an environment variable for the current session: set RECORD=true. See this page for more.
  • In PowerShell, you can use the $env:RECORD = 'true' command for that. See this article for more.
  • You can also make a persistent environment variable by hand in the Windows computer settings. See this article for how.
• When the environment variable is set, run go tests ./lexers.

Chroma will now regenerate the test files and print its results to the console window.

Documentation

Overview

Package lexers contains the registry of all lexers.

Sub-packages contain lexer implementations.

Index

• Variables
• func Analyse(text string) chroma.Lexer
• func Get(name string) chroma.Lexer
• func Match(filename string) chroma.Lexer
• func MatchMimeType(mimeType string) chroma.Lexer
• func Names(withAliases bool) []string
• func Register(lexer chroma.Lexer) chroma.Lexer

Variables

var Fallback = internal.Fallback

Fallback lexer if no other is found.

var Registry = internal.Registry

Registry of Lexers.

Functions

func Analyse

func Analyse(text string) chroma.Lexer

Analyse text content and return the "best" lexer..

func Get

func Get(name string) chroma.Lexer

Get a Lexer by name, alias or file extension.

func Match

func Match(filename string) chroma.Lexer

Match returns the first lexer matching filename.

func MatchMimeType

func MatchMimeType(mimeType string) chroma.Lexer

MatchMimeType attempts to find a lexer for the given MIME type.

func Names

func Names(withAliases bool) []string

Names of all lexers, optionally including aliases.

func Register

func Register(lexer chroma.Lexer) chroma.Lexer

Register a Lexer with the global registry.