grindlemire/go-tui code browser

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452

/**
 * Tree-sitter grammar for GSX DSL (.gsx files)
 */

module.exports = grammar({
  name: "gsx",

  extras: ($) => [/\s/, $.comment],

  word: ($) => $.identifier,

  // state_declaration (name := call_expression) overlaps with _expression since
  // "identifier := call_expression" could be parsed as either. Tree-sitter resolves
  // this by preferring the longer match (state_declaration) when both apply.
  // This is intentional: inside a component body, `x := tui.NewState(0)` should
  // parse as a state_declaration, not as an expression.
  conflicts: ($) => [[$.state_declaration, $._expression], [$.func_type]],

  rules: {
    source_file: ($) =>
      seq(
        optional($.package_clause),
        optional($.import_section),
        repeat(
          choice(
            $.component_declaration,
            $.function_declaration,
            $.type_struct_declaration,
            $.go_declaration,
          ),
        ),
      ),

    // Package clause
    package_clause: ($) => seq("package", field("name", $.identifier)),

    // Import section
    import_section: ($) => repeat1($.import_declaration),

    import_declaration: ($) =>
      seq("import", choice($.import_spec, $.import_spec_list)),

    import_spec_list: ($) => seq("(", repeat($.import_spec), ")"),

    import_spec: ($) =>
      seq(optional(field("alias", $.identifier)), field("path", $.string)),

    // Component declaration: supports both function and method forms
    //   templ Name(params) { body }
    //   templ (s *Type) Render() { body }
    component_declaration: ($) =>
      choice(
        seq(
          "templ",
          field("name", $.identifier),
          field("parameters", $.parameter_list),
          field("body", $.component_body),
        ),
        seq(
          "templ",
          field("receiver", $.receiver),
          field("name", $.identifier),
          "(",
          ")",
          field("body", $.component_body),
        ),
      ),

    // Receiver for method declarations: (name *Type) or (name Type)
    receiver: ($) =>
      seq(
        "(",
        field("name", $.identifier),
        field("type", $.type_expression),
        ")",
      ),

    parameter_list: ($) =>
      seq(
        "(",
        optional(
          seq($.parameter, repeat(seq(",", $.parameter)), optional(",")),
        ),
        ")",
      ),

    parameter: ($) =>
      seq(field("name", $.identifier), field("type", $.type_expression)),

    type_expression: ($) =>
      choice(
        $.identifier,
        $.qualified_type,
        $.slice_type,
        $.pointer_type,
        $.generic_type,
        $.map_type,
        $.func_type,
      ),

    qualified_type: ($) => seq($.identifier, ".", $.identifier),
    slice_type: ($) => seq("[", "]", $.type_expression),
    pointer_type: ($) => seq("*", $.type_expression),
    // Map type: map[K]V
    map_type: ($) => seq("map", "[", $.type_expression, "]", $.type_expression),
    // Function type: func(), func(T), func(T1, T2) R, func() (R1, R2)
    func_type: ($) =>
      seq(
        "func",
        "(",
        optional(seq($.type_expression, repeat(seq(",", $.type_expression)))),
        ")",
        optional($.return_type),
      ),
    // Generic type: Type[T] or pkg.Type[T]
    generic_type: ($) =>
      seq(
        choice($.identifier, $.qualified_type),
        "[",
        $.type_expression,
        repeat(seq(",", $.type_expression)),
        "]",
      ),

    // Struct type declaration: type Name struct { fields }
    // Uses prec(1) to take priority over the opaque go_declaration for struct types.
    type_struct_declaration: ($) =>
      prec(
        1,
        seq(
          "type",
          field("name", $.identifier),
          "struct",
          field("body", $.struct_body),
        ),
      ),

    struct_body: ($) => seq("{", repeat($.struct_field), "}"),

    struct_field: ($) =>
      seq(field("name", $.identifier), field("type", $.type_expression)),

    component_body: ($) => seq("{", repeat($._child), "}"),

    _child: ($) =>
      choice(
        $.element,
        $.for_statement,
        $.if_statement,
        $.let_binding,
        $.state_declaration,
        $.component_call,
        $.children_slot,
        $.go_expression,
      ),

    // Elements
    element: ($) => choice($.self_closing_element, $.element_with_children),

    self_closing_element: ($) =>
      seq("<", field("tag", $.identifier), repeat($.attribute), "/", ">"),

    element_with_children: ($) =>
      seq(
        "<",
        field("tag", $.identifier),
        repeat($.attribute),
        ">",
        repeat($._element_child),
        "</",
        $.identifier,
        ">",
      ),

    _element_child: ($) =>
      choice(
        $.element,
        $.for_statement,
        $.if_statement,
        $.let_binding,
        $.component_call,
        $.children_slot,
        $.go_expression,
        $.text_content,
      ),

    text_content: ($) => /[^<>{}@\s][^<>{}@\n]*/,

    attribute: ($) =>
      seq(
        field("name", $.identifier),
        optional(seq("=", field("value", $._attribute_value))),
      ),

    _attribute_value: ($) => choice($.string, $.go_expression, $.number),

    // Control flow
    for_statement: ($) =>
      seq("for", field("clause", $.for_clause), field("body", $.block)),

    for_clause: ($) =>
      seq(
        optional(seq(field("index", $.identifier), ",")),
        field("value", $.identifier),
        ":=",
        "range",
        field("collection", $._expression),
      ),

    if_statement: ($) =>
      seq(
        "if",
        field("condition", $._expression),
        field("consequence", $.block),
        optional(
          seq("else", field("alternative", choice($.block, $.if_statement))),
        ),
      ),

    let_binding: ($) =>
      choice(
        // := syntax
        seq(
          field("name", $.identifier),
          ":=",
          field("value", choice($.element, $.component_call)),
        ),
        // var syntax
        seq(
          "var",
          field("name", $.identifier),
          "=",
          field("value", choice($.element, $.component_call)),
        ),
      ),

    // State declaration: name := tui.NewState(value)
    state_declaration: ($) =>
      seq(
        field("name", $.identifier),
        ":=",
        field("initializer", $.call_expression),
      ),

    // Component call: @Name(args) or @Name(args) { children }
    // prec(1) ensures that a '{' after the argument list is parsed as a
    // children block rather than a separate go_expression sibling.
    component_call: ($) =>
      prec.right(
        1,
        seq(
          "@",
          field("name", $.identifier),
          field("arguments", $.argument_list),
          optional(field("children", $.block)),
        ),
      ),

    // Children slot: {children...}
    children_slot: ($) => seq("{", "children", "...", "}"),

    block: ($) => seq("{", repeat($._child), "}"),

    // Go expressions: content between balanced braces, including nested braces
    // and string literals (which may contain unbalanced braces).
    go_expression: ($) => seq("{", $.expression_content, "}"),

    expression_content: ($) =>
      repeat1(
        choice(
          $.go_string_literal, // Handle string literals so braces inside them don't confuse parsing
          /[^{}"'`]+/, // Non-brace, non-quote content
          $.nested_braces,
        ),
      ),

    // String and rune literals inside Go expressions — captures "...", '...', `...`
    // to prevent their contents (which may include braces) from being parsed as structure.
    go_string_literal: ($) =>
      choice(
        /"[^"\\]*(?:\\.[^"\\]*)*"/, // Double-quoted string with escape handling
        /`[^`]*`/, // Backtick (raw) string
        /'[^'\\]'/, // Simple rune literal: 'a', '/', etc.
        /'\\.'/, // Escaped rune literal: '\n', '\\', '\'', etc.
      ),

    nested_braces: ($) =>
      seq(
        "{",
        repeat(choice($.go_string_literal, /[^{}"'`]+/, $.nested_braces)),
        "}",
      ),

    // Expressions (simplified)
    _expression: ($) =>
      choice(
        $.identifier,
        $.number,
        $.string,
        $.true,
        $.false,
        $.binary_expression,
        $.call_expression,
        $.selector_expression,
        $.parenthesized_expression,
      ),

    binary_expression: ($) =>
      prec.left(
        1,
        seq(
          $._expression,
          choice(
            "==",
            "!=",
            "<",
            ">",
            "<=",
            ">=",
            "+",
            "-",
            "*",
            "/",
            "&&",
            "||",
          ),
          $._expression,
        ),
      ),

    call_expression: ($) =>
      prec(
        2,
        seq(choice($.identifier, $.selector_expression), $.argument_list),
      ),

    selector_expression: ($) => prec(3, seq($._expression, ".", $.identifier)),

    parenthesized_expression: ($) => seq("(", $._expression, ")"),

    argument_list: ($) =>
      seq(
        "(",
        optional(seq($._expression, repeat(seq(",", $._expression)))),
        ")",
      ),

    // Literals
    identifier: ($) => /[a-zA-Z_][a-zA-Z0-9_]*/,
    number: ($) => /\d+(\.\d+)?/,
    string: ($) => /"[^"]*"/,
    true: ($) => "true",
    false: ($) => "false",

    // Return type: single type or tuple (T1, T2)
    return_type: ($) =>
      choice(
        $.type_expression,
        seq(
          "(",
          $.type_expression,
          repeat(seq(",", $.type_expression)),
          ")",
        ),
      ),

    // Function declarations: supports both regular and method forms
    //   func name(params) returnType { body }
    //   func (recv) name(params) returnType { body }
    function_declaration: ($) =>
      choice(
        seq(
          "func",
          field("name", $.identifier),
          field("parameters", $.parameter_list),
          optional(field("return_type", $.return_type)),
          field("body", $.function_body),
        ),
        seq(
          "func",
          field("receiver", $.receiver),
          field("name", $.identifier),
          field("parameters", $.parameter_list),
          optional(field("return_type", $.return_type)),
          field("body", $.function_body),
        ),
      ),

    // Go declaration: type, var, or const blocks (captured as opaque Go code)
    // Handles non-struct type declarations, grouped declarations, and interface checks.
    // Note: struct declarations are handled by type_struct_declaration above.
    // The preamble uses choice(identifier, punctuation_regex) instead of a single greedy
    // regex so that Go keywords like "struct" are tokenized separately and not consumed
    // as part of the opaque preamble text.
    go_declaration: ($) =>
      choice(
        // Braced form: type Name interface { ... }, var/const ... { ... }
        seq(
          field("keyword", choice("type", "var", "const")),
          field(
            "preamble",
            repeat1(choice($.identifier, /[^\sa-zA-Z_0-9{()"'`\n]+/)),
          ),
          field("body", $.go_brace_body),
        ),
        // Parenthesized form: var ( ... ) or const ( ... )
        seq(
          field("keyword", choice("type", "var", "const")),
          field("body", $.go_paren_body),
        ),
        // Single-line form: var _ tui.Component = (*foo)(nil)
        seq(
          field("keyword", choice("type", "var", "const")),
          field(
            "preamble",
            repeat1(choice($.identifier, /[^\sa-zA-Z_0-9{()"'`\n]+/)),
          ),
          // Parenthesized expressions in single-line form
          optional(seq("(", /[^)]*/, ")")),
          optional(seq("(", /[^)]*/, ")")),
        ),
      ),

    // Brace-delimited body (for interface, etc. — struct handled by type_struct_declaration)
    go_brace_body: ($) => seq("{", optional($.go_code_content), "}"),

    // Parenthesis-delimited body (for grouped var/const/type)
    go_paren_body: ($) =>
      seq(
        "(",
        repeat(choice($.go_string_literal, /[^()"'`]+/, $.nested_parens)),
        ")",
      ),

    nested_parens: ($) =>
      seq(
        "(",
        repeat(choice($.go_string_literal, /[^()"'`]+/, $.nested_parens)),
        ")",
      ),

    function_body: ($) => seq("{", optional($.go_code_content), "}"),

    // Named node for Go code content inside function/brace bodies.
    // Having a named node enables Go language injection for syntax highlighting.
    go_code_content: ($) =>
      repeat1(choice($.go_string_literal, /[^{}"'`]+/, $.nested_braces)),

    // Comments (for explicit use in the AST)
    comment: ($) => choice(/\/\/.*/, /\/\*[^*]*\*+([^/*][^*]*\*+)*\//),
  },
});