From 0151e94463bc826be6eecac29ad1c588169f9976 Mon Sep 17 00:00:00 2001
From: Vasil Markoukin <1istoobig@gmail.com>
Date: Mon, 25 Nov 2024 13:09:52 +0300
Subject: [PATCH] feat: support non-indented cases in Scala3 match expression
 ----

Addresses #264
---
 .gitignore                  |  4 ++++
 grammar.js                  |  7 ++++++-
 test/corpus/expressions.txt | 36 ++++++++++++++++++++++++++----------
 3 files changed, 36 insertions(+), 11 deletions(-)

diff --git a/.gitignore b/.gitignore
index 308fcab..71f786a 100644
--- a/.gitignore
+++ b/.gitignore
@@ -38,3 +38,7 @@ dist/
 *.tar.gz
 *.tgz
 *.zip
+
+# scala-cli
+.scala-build
+.bsp
diff --git a/grammar.js b/grammar.js
index f30d2b9..51de0af 100644
--- a/grammar.js
+++ b/grammar.js
@@ -95,6 +95,8 @@ module.exports = grammar({
     [$._if_condition, $._simple_expression],
     // _postfix_expression_choice  ':'  '('  wildcard  •  ':'  …
     [$.binding, $._simple_type],
+    // expression  'match'  'case'  _case_pattern  ';'  _automatic_semicolon  expression  •  'match'  …
+    [$.match_expression, $._block],
   ],
 
   word: $ => $._alpha_identifier,
@@ -806,6 +808,9 @@ module.exports = grammar({
     indented_cases: $ =>
       prec.left(seq($._indent, repeat1($.case_clause), $._outdent)),
 
+    non_indented_cases: $ =>
+      prec.right(sep1($._automatic_semicolon, $.case_clause)),
+
     _indented_type_cases: $ =>
       prec.left(seq($._indent, repeat1($.type_case_clause), $._outdent)),
 
@@ -1157,7 +1162,7 @@ module.exports = grammar({
         optional($.inline_modifier),
         field("value", $.expression),
         "match",
-        field("body", choice($.case_block, $.indented_cases)),
+        field("body", choice($.case_block, $.indented_cases, $.non_indented_cases)),
       ),
 
     try_expression: $ =>
diff --git a/test/corpus/expressions.txt b/test/corpus/expressions.txt
index 6c5613f..62873cb 100644
--- a/test/corpus/expressions.txt
+++ b/test/corpus/expressions.txt
@@ -689,12 +689,12 @@ def matchTest(x: Int): String = x match {
   case 3 => {
     "3"
   }
-  case 4 => 
+  case 4 =>
     ;
   case A if a == 1 =>
   case A if a == 2 => 2
   case ((i, _)) => i
-  case s"$l1 -- $l2" => 
+  case s"$l1 -- $l2" =>
     l1 + l2
   case _ =>
     val x = "many"
@@ -791,6 +791,10 @@ def matchTest(x: Int): String =
     case _ =>
       val x = "many"
       "more"
+  y match
+  case 0 => "zero"
+    case 1 => "one"
+  case _ => "idk"
 
 --------------------------------------------------------------------------------
 
@@ -837,6 +841,18 @@ def matchTest(x: Int): String =
             (val_definition
               (identifier)
               (string))
+            (string))))
+      (match_expression
+        (identifier)
+        (non_indented_cases
+          (case_clause
+            (integer_literal)
+            (string))
+          (case_clause
+            (integer_literal)
+            (string))
+          (case_clause
+            (wildcard)
             (string)))))))
 
 ================================================================================
@@ -850,8 +866,8 @@ class C {
     a
       .b
       // comment1
-      /* 
-         comment2 
+      /*
+         comment2
       */
       .c
   }
@@ -1105,11 +1121,11 @@ object O {
   val l = a => a + 1
   val b = (x: Int, y: Int) => { x * y }
   val f = _ => 2
-  foo { i => 
-    val x = 2 + i 
+  foo { i =>
+    val x = 2 + i
     x
   }
-  { x => 
+  { x =>
     val y = 2 * x
     y * y
   }
@@ -1223,7 +1239,7 @@ Unit expressions
 ================================================================================
 
 val x = ()
-def f(): Unit = { (   
+def f(): Unit = { (
 ); }
 
 --------------------------------------------------------------------------------
@@ -1649,9 +1665,9 @@ class A:
 Inline matches (Scala 3)
 ================================================================================
 
-def hello = 
+def hello =
   inline c match {
-    case 1 => 
+    case 1 =>
   }
 
 --------------------------------------------------------------------------------