[ruby/yarp] Simplify multi-target parsing

This simplifies how we handle multi-targets, and also fixes a bug we
had where for loops were always getting multi-targets, even when there
was only a single target.

https://github.com/ruby/yarp/commit/31eb8b7ad5

3 files changed, 24 insertions, 56 deletions

diff --git a/test/yarp/snapshots/for.txt b/test/yarp/snapshots/for.txt
index 3475d585e2..e8b3868b7b 100644
--- a/test/yarp/snapshots/for.txt
+++ b/test/yarp/snapshots/for.txt
@@ -5,13 +5,9 @@
     └── body: (length: 6)
         ├── @ ForNode (location: (0...20))
         │   ├── index:
-        │   │   @ MultiTargetNode (location: (4...5))
-        │   │   ├── targets: (length: 1)
-        │   │   │   └── @ LocalVariableTargetNode (location: (4...5))
-        │   │   │       ├── name: :i
-        │   │   │       └── depth: 0
-        │   │   ├── lparen_loc: ∅
-        │   │   └── rparen_loc: ∅
+        │   │   @ LocalVariableTargetNode (location: (4...5))
+        │   │   ├── name: :i
+        │   │   └── depth: 0
         │   ├── collection:
         │   │   @ RangeNode (location: (9...14))
         │   │   ├── left:
@@ -34,13 +30,9 @@
         │   └── end_keyword_loc: (17...20) = "end"
         ├── @ ForNode (location: (22...44))
         │   ├── index:
-        │   │   @ MultiTargetNode (location: (26...27))
-        │   │   ├── targets: (length: 1)
-        │   │   │   └── @ LocalVariableTargetNode (location: (26...27))
-        │   │   │       ├── name: :i
-        │   │   │       └── depth: 0
-        │   │   ├── lparen_loc: ∅
-        │   │   └── rparen_loc: ∅
+        │   │   @ LocalVariableTargetNode (location: (26...27))
+        │   │   ├── name: :i
+        │   │   └── depth: 0
         │   ├── collection:
         │   │   @ RangeNode (location: (31...36))
         │   │   ├── left:
@@ -130,13 +122,9 @@
         │   └── end_keyword_loc: (91...94) = "end"
         ├── @ ForNode (location: (96...119))
         │   ├── index:
-        │   │   @ MultiTargetNode (location: (100...101))
-        │   │   ├── targets: (length: 1)
-        │   │   │   └── @ LocalVariableTargetNode (location: (100...101))
-        │   │   │       ├── name: :i
-        │   │   │       └── depth: 0
-        │   │   ├── lparen_loc: ∅
-        │   │   └── rparen_loc: ∅
+        │   │   @ LocalVariableTargetNode (location: (100...101))
+        │   │   ├── name: :i
+        │   │   └── depth: 0
         │   ├── collection:
         │   │   @ RangeNode (location: (105...110))
         │   │   ├── left:
@@ -159,13 +147,9 @@
         │   └── end_keyword_loc: (116...119) = "end"
         └── @ ForNode (location: (121...143))
             ├── index:
-            │   @ MultiTargetNode (location: (125...126))
-            │   ├── targets: (length: 1)
-            │   │   └── @ LocalVariableTargetNode (location: (125...126))
-            │   │       ├── name: :i
-            │   │       └── depth: 0
-            │   ├── lparen_loc: ∅
-            │   └── rparen_loc: ∅
+            │   @ LocalVariableTargetNode (location: (125...126))
+            │   ├── name: :i
+            │   └── depth: 0
             ├── collection:
             │   @ RangeNode (location: (130...135))
             │   ├── left:
diff --git a/test/yarp/snapshots/unparser/corpus/literal/for.txt b/test/yarp/snapshots/unparser/corpus/literal/for.txt
index 682c2bcb14..62fde3418d 100644
--- a/test/yarp/snapshots/unparser/corpus/literal/for.txt
+++ b/test/yarp/snapshots/unparser/corpus/literal/for.txt
@@ -13,13 +13,9 @@
         │   │   └── arguments: (length: 1)
         │   │       └── @ ForNode (location: (4...29))
         │   │           ├── index:
-        │   │           │   @ MultiTargetNode (location: (8...9))
-        │   │           │   ├── targets: (length: 1)
-        │   │           │   │   └── @ LocalVariableTargetNode (location: (8...9))
-        │   │           │   │       ├── name: :a
-        │   │           │   │       └── depth: 0
-        │   │           │   ├── lparen_loc: ∅
-        │   │           │   └── rparen_loc: ∅
+        │   │           │   @ LocalVariableTargetNode (location: (8...9))
+        │   │           │   ├── name: :a
+        │   │           │   └── depth: 0
         │   │           ├── collection:
         │   │           │   @ CallNode (location: (13...16))
         │   │           │   ├── receiver: ∅
@@ -54,13 +50,9 @@
         │   └── name: "bar"
         ├── @ ForNode (location: (31...56))
         │   ├── index:
-        │   │   @ MultiTargetNode (location: (35...36))
-        │   │   ├── targets: (length: 1)
-        │   │   │   └── @ LocalVariableTargetNode (location: (35...36))
-        │   │   │       ├── name: :a
-        │   │   │       └── depth: 0
-        │   │   ├── lparen_loc: ∅
-        │   │   └── rparen_loc: ∅
+        │   │   @ LocalVariableTargetNode (location: (35...36))
+        │   │   ├── name: :a
+        │   │   └── depth: 0
         │   ├── collection:
         │   │   @ CallNode (location: (40...43))
         │   │   ├── receiver: ∅
diff --git a/test/yarp/snapshots/whitequark/for.txt b/test/yarp/snapshots/whitequark/for.txt
index daf73081e6..285dadd26d 100644
--- a/test/yarp/snapshots/whitequark/for.txt
+++ b/test/yarp/snapshots/whitequark/for.txt
@@ -5,13 +5,9 @@
     └── body: (length: 2)
         ├── @ ForNode (location: (0...24))
         │   ├── index:
-        │   │   @ MultiTargetNode (location: (4...5))
-        │   │   ├── targets: (length: 1)
-        │   │   │   └── @ LocalVariableTargetNode (location: (4...5))
-        │   │   │       ├── name: :a
-        │   │   │       └── depth: 0
-        │   │   ├── lparen_loc: ∅
-        │   │   └── rparen_loc: ∅
+        │   │   @ LocalVariableTargetNode (location: (4...5))
+        │   │   ├── name: :a
+        │   │   └── depth: 0
         │   ├── collection:
         │   │   @ CallNode (location: (9...12))
         │   │   ├── receiver: ∅
@@ -47,13 +43,9 @@
         │   └── end_keyword_loc: (21...24) = "end"
         └── @ ForNode (location: (26...48))
             ├── index:
-            │   @ MultiTargetNode (location: (30...31))
-            │   ├── targets: (length: 1)
-            │   │   └── @ LocalVariableTargetNode (location: (30...31))
-            │   │       ├── name: :a
-            │   │       └── depth: 0
-            │   ├── lparen_loc: ∅
-            │   └── rparen_loc: ∅
+            │   @ LocalVariableTargetNode (location: (30...31))
+            │   ├── name: :a
+            │   └── depth: 0
             ├── collection:
             │   @ CallNode (location: (35...38))
             │   ├── receiver: ∅