fix: allow "match" on LHS of named_expression (#153)

Fixes #150
tree-sitter · Feb 7, 2022 · d8521fa · d8521fa
1 parent 0d17ed6
commit d8521fa
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Showing 7 changed files with 29,368 additions and 29,312 deletions.
diff --git a/grammar.js b/grammar.js
@@ -190,11 +190,16 @@ module.exports = grammar({
     ),
 
     named_expression: $ => seq(
-      field('name', $.identifier),
+      field('name', $._named_expresssion_lhs),
       ':=',
       field('value', $.expression)
     ),
 
+    _named_expresssion_lhs: $ => choice(
+      $.identifier,
+      alias('match', $.identifier), // ambiguity with match statement: only ":" at end of line decides if "match" keyword
+    ),
+
     return_statement: $ => seq(
       'return',
       optional($._expressions)
@@ -261,7 +266,9 @@ module.exports = grammar({
       commaSep1(field('subject', $.expression)),
       optional(','),
       ':',
-      repeat(field('alternative', $.case_clause))),
+      $.case_block),
+
+    case_block: $ => repeat1(field('alternative', $.case_clause)),
 
     case_clause: $ => seq(
       'case',
@@ -499,7 +506,7 @@ module.exports = grammar({
 
     pattern: $ => choice(
       $.identifier,
-      alias("match", $.identifier), // ambiguity with match statement: only ":" at end of line decides if "match" keyword
+      alias('match', $.identifier), // ambiguity with match statement: only ":" at end of line decides if "match" keyword
       $.keyword_identifier,
       $.subscript,
       $.attribute,

diff --git a/src/grammar.json b/src/grammar.json
@@ -604,7 +604,7 @@
           "name": "name",
           "content": {
             "type": "SYMBOL",
-            "name": "identifier"
+            "name": "_named_expresssion_lhs"
           }
         },
         {
@@ -621,6 +621,24 @@
         }
       ]
     },
+    "_named_expresssion_lhs": {
+      "type": "CHOICE",
+      "members": [
+        {
+          "type": "SYMBOL",
+          "name": "identifier"
+        },
+        {
+          "type": "ALIAS",
+          "content": {
+            "type": "STRING",
+            "value": "match"
+          },
+          "named": true,
+          "value": "identifier"
+        }
+      ]
+    },
     "return_statement": {
       "type": "SEQ",
       "members": [
@@ -942,18 +960,22 @@
           "value": ":"
         },
         {
-          "type": "REPEAT",
-          "content": {
-            "type": "FIELD",
-            "name": "alternative",
-            "content": {
-              "type": "SYMBOL",
-              "name": "case_clause"
-            }
-          }
+          "type": "SYMBOL",
+          "name": "case_block"
         }
       ]
     },
+    "case_block": {
+      "type": "REPEAT1",
+      "content": {
+        "type": "FIELD",
+        "name": "alternative",
+        "content": {
+          "type": "SYMBOL",
+          "name": "case_clause"
+        }
+      }
+    },
     "case_clause": {
       "type": "SEQ",
       "members": [

diff --git a/src/node-types.json b/src/node-types.json
@@ -796,6 +796,22 @@
       }
     }
   },
+  {
+    "type": "case_block",
+    "named": true,
+    "fields": {
+      "alternative": {
+        "multiple": true,
+        "required": true,
+        "types": [
+          {
+            "type": "case_clause",
+            "named": true
+          }
+        ]
+      }
+    }
+  },
   {
     "type": "case_clause",
     "named": true,
@@ -1901,16 +1917,6 @@
     "type": "match_statement",
     "named": true,
     "fields": {
-      "alternative": {
-        "multiple": true,
-        "required": false,
-        "types": [
-          {
-            "type": "case_clause",
-            "named": true
-          }
-        ]
-      },
       "subject": {
         "multiple": true,
         "required": true,
@@ -1921,6 +1927,16 @@
           }
         ]
       }
+    },
+    "children": {
+      "multiple": false,
+      "required": true,
+      "types": [
+        {
+          "type": "case_block",
+          "named": true
+        }
+      ]
     }
   },
   {