AliasNode: {left, right} -> {new_name, old_name}

- Fixes #348 except for the `keyword_loc`

Author: davidwessman

lib/syntax_tree/dsl.rb

@@ -32,8 +32,12 @@ def EndContent(value)
     end
 
     # Create a new AliasNode node.
-    def AliasNode(left, right)
-      AliasNode.new(left: left, right: right, location: Location.default)
+    def AliasNode(new_name, old_name)
+      AliasNode.new(
+        new_name: new_name,
+        old_name: old_name,
+        location: Location.default
+      )
     end
 
     # Create a new ARef node.

lib/syntax_tree/field_visitor.rb

@@ -67,8 +67,8 @@ def visit_aref_field(node)
 
       def visit_alias(node)
         node(node, "alias") do
-          field("left", node.left)
-          field("right", node.right)
+          field("new_name", node.new_name)
+          field("old_name", node.old_name)
           comments(node)
         end
       end

lib/syntax_tree/index.rb

@@ -475,7 +475,8 @@ def initialize
 
         visit_methods do
           def visit_alias(node)
-            if node.left.is_a?(SymbolLiteral) && node.right.is_a?(SymbolLiteral)
+            if node.new_name.is_a?(SymbolLiteral) &&
+                 node.old_name.is_a?(SymbolLiteral)
               location =
                 Location.new(
                   node.location.start_line,
@@ -484,7 +485,7 @@ def visit_alias(node)
 
               results << AliasMethodDefinition.new(
                 nesting.dup,
-                node.left.value.value.to_sym,
+                node.new_name.value.value.to_sym,
                 location,
                 comments_for(node)
               )

lib/syntax_tree/mutation_visitor.rb

@@ -62,7 +62,10 @@ def visit___end__(node)
 
       # Visit a AliasNode node.
       def visit_alias(node)
-        node.copy(left: visit(node.left), right: visit(node.right))
+        node.copy(
+          new_name: visit(node.new_name),
+          old_name: visit(node.old_name)
+        )
       end
 
       # Visit a ARef node.

lib/syntax_tree/node.rb

@@ -485,17 +485,17 @@ def format(q)
     end
 
     # [DynaSymbol | GVar | SymbolLiteral] the new name of the method
-    attr_reader :left
+    attr_reader :new_name
 
     # [Backref | DynaSymbol | GVar | SymbolLiteral] the old name of the method
-    attr_reader :right
+    attr_reader :old_name
 
     # [Array[ Comment | EmbDoc ]] the comments attached to this node
     attr_reader :comments
 
-    def initialize(left:, right:, location:)
-      @left = left
-      @right = right
+    def initialize(new_name:, old_name:, location:)
+      @new_name = new_name
+      @old_name = old_name
       @location = location
       @comments = []
     end
@@ -505,14 +505,14 @@ def accept(visitor)
     end
 
     def child_nodes
-      [left, right]
+      [new_name, old_name]
     end
 
-    def copy(left: nil, right: nil, location: nil)
+    def copy(new_name: nil, old_name: nil, location: nil)
       node =
         AliasNode.new(
-          left: left || self.left,
-          right: right || self.right,
+          new_name: new_name || self.new_name,
+          old_name: old_name || self.old_name,
           location: location || self.location
         )
 
@@ -523,31 +523,41 @@ def copy(left: nil, right: nil, location: nil)
     alias deconstruct child_nodes
 
     def deconstruct_keys(_keys)
-      { left: left, right: right, location: location, comments: comments }
+      {
+        new_name: new_name,
+        old_name: old_name,
+        location: location,
+        comments: comments
+      }
     end
 
     def format(q)
       keyword = "alias "
-      left_argument = AliasArgumentFormatter.new(left)
+      new_name_argument = AliasArgumentFormatter.new(new_name)
 
       q.group do
         q.text(keyword)
-        q.format(left_argument, stackable: false)
+        q.format(new_name_argument, stackable: false)
         q.group do
           q.nest(keyword.length) do
-            left_argument.comments.any? ? q.breakable_force : q.breakable_space
-            q.format(AliasArgumentFormatter.new(right), stackable: false)
+            if new_name_argument.comments.any?
+              q.breakable_force
+            else
+              q.breakable_space
+            end
+            q.format(AliasArgumentFormatter.new(old_name), stackable: false)
           end
         end
       end
     end
 
     def ===(other)
-      other.is_a?(AliasNode) && left === other.left && right === other.right
+      other.is_a?(AliasNode) && new_name === other.new_name &&
+        old_name === other.old_name
     end
 
     def var_alias?
-      left.is_a?(GVar)
+      new_name.is_a?(GVar)
     end
   end
 

lib/syntax_tree/parser.rb

@@ -447,16 +447,16 @@ def on___end__(value)
 
     # :call-seq:
     #   on_alias: (
-    #     (DynaSymbol | SymbolLiteral) left,
-    #     (DynaSymbol | SymbolLiteral) right
+    #     (DynaSymbol | SymbolLiteral) new_name,
+    #     (DynaSymbol | SymbolLiteral) old_name
     #   ) -> AliasNode
-    def on_alias(left, right)
+    def on_alias(new_name, old_name)
       keyword = consume_keyword(:alias)
 
       AliasNode.new(
-        left: left,
-        right: right,
-        location: keyword.location.to(right.location)
+        new_name: new_name,
+        old_name: old_name,
+        location: keyword.location.to(old_name.location)
       )
     end
 
@@ -3902,14 +3902,14 @@ def on_until_mod(predicate, statement)
     end
 
     # :call-seq:
-    #   on_var_alias: (GVar left, (Backref | GVar) right) -> AliasNode
-    def on_var_alias(left, right)
+    #   on_var_alias: (GVar new_name, (Backref | GVar) old_name) -> AliasNode
+    def on_var_alias(new_name, old_name)
       keyword = consume_keyword(:alias)
 
       AliasNode.new(
-        left: left,
-        right: right,
-        location: keyword.location.to(right.location)
+        new_name: new_name,
+        old_name: old_name,
+        location: keyword.location.to(old_name.location)
       )
     end
 

lib/syntax_tree/translation/parser.rb

@@ -94,7 +94,7 @@ def visit(node)
         def visit_alias(node)
           s(
             :alias,
-            [visit(node.left), visit(node.right)],
+            [visit(node.new_name), visit(node.old_name)],
             smap_keyword_bare(
               srange_length(node.start_char, 5),
               srange_node(node)

lib/syntax_tree/yarv/compiler.rb

@@ -339,8 +339,8 @@ def visit_END(node)
       def visit_alias(node)
         iseq.putspecialobject(PutSpecialObject::OBJECT_VMCORE)
         iseq.putspecialobject(PutSpecialObject::OBJECT_CBASE)
-        visit(node.left)
-        visit(node.right)
+        visit(node.new_name)
+        visit(node.old_name)
         iseq.send(YARV.calldata(:"core#set_method_alias", 3))
       end