Crystal language support (helix-editor#4993)

book/src/generated/lang-support.md

@@ -16,6 +16,7 @@
 | common-lisp | ✓ |  |  | `cl-lsp` |
 | cpon | ✓ |  | ✓ |  |
 | cpp | ✓ | ✓ | ✓ | `clangd` |
+| crystal | ✓ |  |  |  |
 | css | ✓ |  |  | `vscode-css-language-server` |
 | cue | ✓ |  |  | `cuelsp` |
 | d | ✓ | ✓ | ✓ | `serve-d` |

languages.toml

@@ -223,6 +223,18 @@ args = { console = "internalConsole", attachCommands = [ "platform select remote
 name = "cpp"
 source = { git = "https://github.com/tree-sitter/tree-sitter-cpp", rev = "d5e90fba898f320db48d81ddedd78d52c67c1fed" }
 
+[[language]]
+name = "crystal"
+scope = "source.cr"
+file-types = ["cr"]
+roots = ["shard.yml", "shard.lock"]
+comment-token = "#"
+indent = { tab-width = 2, unit = "  " }
+
+[[grammar]]
+name = "crystal"
+source = { git = "https://github.com/will/tree-sitter-crystal", rev = "15597b307b18028b04d288561f9c29794621562b" }
+
 [[language]]
 name = "c-sharp"
 scope = "source.csharp"

runtime/queries/crystal/highlights.scm

@@ -0,0 +1,66 @@
+[
+  "class"
+  "struct"
+  "module"
+
+  "def"
+  "alias"
+  "do"
+  "end"
+
+  "require"
+  "include"
+  "extend"
+] @keyword
+
+[
+  "[" "]"
+  "(" ")"
+  "{" "}"
+] @punctuation.bracket
+
+(operator) @operator
+
+(comment) @comment
+
+; literals
+
+(nil) @constant.builtin
+(bool) @constant.builtin.boolean
+
+(integer) @constant.numeric.integer
+(float) @constant.numeric.float
+
+[
+  (string)
+  (char)
+  (commandLiteral)
+] @string
+
+(symbol) @string.special.symbol
+
+(regex) @string.special.regex
+
+; variables
+
+(local_variable) @variable
+
+[
+  (instance_variable)
+  (class_variable)
+] @variable.other.member
+
+(constant) @constant
+
+; type defintitions
+
+(type_identifier) @constructor
+
+; method definition/call
+(identifier) @function.method
+
+; types
+(generic_type) @type
+(union_type) @type
+(type_identifier) @type
+