[ruby/prism] Invalid pinned locals in pattern matching

https://github.com/ruby/prism/commit/3a67b37a56

6 files changed, 28 insertions, 11 deletions

diff --git a/prism/diagnostic.c b/prism/diagnostic.c
index b3a8282cda..fd5dce5a04 100644
--- a/prism/diagnostic.c
+++ b/prism/diagnostic.c
@@ -192,6 +192,7 @@ static const char* const diagnostic_messages[PM_DIAGNOSTIC_ID_LEN] = {
     [PM_ERR_MODULE_TERM]                        = "expected an `end` to close the `module` statement",
     [PM_ERR_MULTI_ASSIGN_MULTI_SPLATS]          = "multiple splats in multiple assignment",
     [PM_ERR_NOT_EXPRESSION]                     = "expected an expression after `not`",
+    [PM_ERR_NO_LOCAL_VARIABLE]                  = "%.*s: no such local variable",
     [PM_ERR_NUMBER_LITERAL_UNDERSCORE]          = "number literal ending with a `_`",
     [PM_ERR_NUMBERED_PARAMETER_NOT_ALLOWED]     = "numbered parameters are not allowed when an ordinary parameter is defined",
     [PM_ERR_NUMBERED_PARAMETER_OUTER_SCOPE]     = "numbered parameter is already used in outer scope",
diff --git a/prism/diagnostic.h b/prism/diagnostic.h
index c88a704488..08a3284abf 100644
--- a/prism/diagnostic.h
+++ b/prism/diagnostic.h
@@ -184,6 +184,7 @@ typedef enum {
     PM_ERR_MODULE_TERM,
     PM_ERR_MULTI_ASSIGN_MULTI_SPLATS,
     PM_ERR_NOT_EXPRESSION,
+    PM_ERR_NO_LOCAL_VARIABLE,
     PM_ERR_NUMBER_LITERAL_UNDERSCORE,
     PM_ERR_NUMBERED_PARAMETER_NOT_ALLOWED,
     PM_ERR_NUMBERED_PARAMETER_OUTER_SCOPE,
diff --git a/prism/prism.c b/prism/prism.c
index ec51bf06fa..5746399ff7 100644
--- a/prism/prism.c
+++ b/prism/prism.c
@@ -13352,8 +13352,15 @@ parse_pattern_primitive(pm_parser_t *parser, pm_diagnostic_id_t diag_id) {
             // expression to determine if it's a variable or an expression.
             switch (parser->current.type) {
                 case PM_TOKEN_IDENTIFIER: {
+                    int depth = pm_parser_local_depth(parser, &parser->current);
+
+                    if (depth == -1) {
+                        depth = 0;
+                        PM_PARSER_ERR_TOKEN_FORMAT(parser, parser->current, PM_ERR_NO_LOCAL_VARIABLE, (int) (parser->current.end - parser->current.start), parser->current.start);
+                    }
+
+                    pm_node_t *variable = (pm_node_t *) pm_local_variable_read_node_create(parser, &parser->current, (uint32_t) depth);
                     parser_lex(parser);
-                    pm_node_t *variable = (pm_node_t *) pm_local_variable_read_node_create(parser, &parser->previous, 0);
 
                     return (pm_node_t *) pm_pinned_variable_node_create(parser, &operator, variable);
                 }
diff --git a/test/prism/fixtures/patterns.txt b/test/prism/fixtures/patterns.txt
index d73c8d025e..dcd6786d4b 100644
--- a/test/prism/fixtures/patterns.txt
+++ b/test/prism/fixtures/patterns.txt
@@ -51,7 +51,7 @@ foo => __LINE__ .. __LINE__
 foo => __ENCODING__ .. __ENCODING__
 foo => -> { bar } .. -> { bar }
 
-foo => ^bar
+bar = 1; foo => ^bar
 foo => ^@bar
 foo => ^@@bar
 foo => ^$bar
diff --git a/test/prism/location_test.rb b/test/prism/location_test.rb
index 809c1bd8ae..e5b7546925 100644
--- a/test/prism/location_test.rb
+++ b/test/prism/location_test.rb
@@ -673,7 +673,7 @@ module Prism
     end
 
     def test_PinnedVariableNode
-      assert_location(PinnedVariableNode, "foo in ^bar", 7...11, &:pattern)
+      assert_location(PinnedVariableNode, "bar = 1; foo in ^bar", 16...20, &:pattern)
     end
 
     def test_PostExecutionNode
diff --git a/test/prism/snapshots/patterns.txt b/test/prism/snapshots/patterns.txt
index aacdbb250e..13179be338 100644
--- a/test/prism/snapshots/patterns.txt
+++ b/test/prism/snapshots/patterns.txt
@@ -2,7 +2,7 @@
 ├── locals: [:bar, :baz, :qux, :b, :a, :foo, :x]
 └── statements:
     @ StatementsNode (location: (1,0)-(202,19))
-    └── body: (length: 175)
+    └── body: (length: 176)
         ├── @ MatchRequiredNode (location: (1,0)-(1,10))
         │   ├── value:
         │   │   @ CallNode (location: (1,0)-(1,3))
@@ -1235,26 +1235,34 @@
         │   │   │               └── depth: 1
         │   │   └── operator_loc: (52,18)-(52,20) = ".."
         │   └── operator_loc: (52,4)-(52,6) = "=>"
-        ├── @ MatchRequiredNode (location: (54,0)-(54,11))
+        ├── @ LocalVariableWriteNode (location: (54,0)-(54,7))
+        │   ├── name: :bar
+        │   ├── depth: 0
+        │   ├── name_loc: (54,0)-(54,3) = "bar"
         │   ├── value:
-        │   │   @ CallNode (location: (54,0)-(54,3))
+        │   │   @ IntegerNode (location: (54,6)-(54,7))
+        │   │   └── flags: decimal
+        │   └── operator_loc: (54,4)-(54,5) = "="
+        ├── @ MatchRequiredNode (location: (54,9)-(54,20))
+        │   ├── value:
+        │   │   @ CallNode (location: (54,9)-(54,12))
         │   │   ├── flags: variable_call
         │   │   ├── receiver: ∅
         │   │   ├── call_operator_loc: ∅
         │   │   ├── name: :foo
-        │   │   ├── message_loc: (54,0)-(54,3) = "foo"
+        │   │   ├── message_loc: (54,9)-(54,12) = "foo"
         │   │   ├── opening_loc: ∅
         │   │   ├── arguments: ∅
         │   │   ├── closing_loc: ∅
         │   │   └── block: ∅
         │   ├── pattern:
-        │   │   @ PinnedVariableNode (location: (54,7)-(54,11))
+        │   │   @ PinnedVariableNode (location: (54,16)-(54,20))
         │   │   ├── variable:
-        │   │   │   @ LocalVariableReadNode (location: (54,8)-(54,11))
+        │   │   │   @ LocalVariableReadNode (location: (54,17)-(54,20))
         │   │   │   ├── name: :bar
         │   │   │   └── depth: 0
-        │   │   └── operator_loc: (54,7)-(54,8) = "^"
-        │   └── operator_loc: (54,4)-(54,6) = "=>"
+        │   │   └── operator_loc: (54,16)-(54,17) = "^"
+        │   └── operator_loc: (54,13)-(54,15) = "=>"
         ├── @ MatchRequiredNode (location: (55,0)-(55,12))
         │   ├── value:
         │   │   @ CallNode (location: (55,0)-(55,3))