Document MultiWriteNode fields

Author: herwinw

config.yml

@@ -3003,8 +3003,36 @@ nodes:
           - CallTargetNode
           - IndexTargetNode
           - MultiTargetNode
+        comment: |
+          Represents the targets expressions before a splat node.
+
+              a, b, * = 1, 2, 3, 4, 5
+              ^^^^
+
+          The splat node can be absent, in that case all target expressions are in the left field.
+
+              a, b, c = 1, 2, 3, 4, 5
+              ^^^^^^^
       - name: rest
         type: node?
+        kind:
+          - ImplicitRestNode
+          - SplatNode
+        comment: |
+          Represents a splat node in the target expression.
+
+              a, b, *c = 1, 2, 3, 4
+                    ^^
+
+          The variable can be empty, this results in a `SplatNode` with a `nil` expression field.
+
+              a, b, * = 1, 2, 3, 4
+                    ^
+
+          If the `*` is omitted, the field will containt an `ImplicitRestNode`
+
+              a, b, = 1, 2, 3, 4
+                  ^
       - name: rights
         type: node[]
         kind:
@@ -3017,14 +3045,39 @@ nodes:
           - CallTargetNode
           - IndexTargetNode
           - MultiTargetNode
+        comment: |
+          Represents the targets expressions after a splat node.
+
+              a, *, b, c = 1, 2, 3, 4, 5
+                    ^^^^
       - name: lparen_loc
         type: location?
+        comment: |
+          The location of the opening parenthesis.
+
+              (a, b, c) = 1, 2, 3
+              ^
       - name: rparen_loc
         type: location?
+        comment: |
+          The location of the closing parenthesis.
+
+              (a, b, c) = 1, 2, 3
+                      ^
       - name: operator_loc
         type: location
+        comment: |
+          The location of the operator.
+
+              a, b, c = 1, 2, 3
+                      ^
       - name: value
         type: node
+        comment: |
+          The value to write to the targets. It can be any [non-void expression](https://github.com/ruby/prism/blob/main/docs/parsing_rules.md#non-void-expression).
+
+              a, b, c = 1, 2, 3
+                        ^^^^^^^
     comment: |
       Represents a write to a multi-target expression.