fix comments not being retained from MethodDefinition in classes

CHANGELOG.md

@@ -1,3 +1,7 @@
+# 1.12.16
+
+ * Fix missing comments not being retained from `MethodDefinition` in classes.
+
 # 1.12.15
 
  * Update `acorn-6to5`.

lib/6to5/transformation/transformers/classes.js

@@ -254,6 +254,7 @@ Class.prototype.pushConstructor = function (method) {
 
   this.hasConstructor = true;
   t.inherits(construct, fn);
+  t.inheritsComments(construct, method);
 
   construct.defaults = fn.defaults;
   construct.params   = fn.params;

lib/6to5/types/index.js

@@ -70,6 +70,9 @@ t.isReferenced = function (node, parent) {
   // we're a property key so we aren't referenced
   if (t.isProperty(parent) && parent.key === node) return false;
 
+  // we're a variable declarator id so we aren't referenced
+  if (t.isVariableDeclarator(parent) && parent.id === node) return false;
+
   var isMemberExpression = t.isMemberExpression(parent);
 
   // we're in a member expression and we're the computed property so we're referenced
@@ -161,7 +164,7 @@ t.toBlock = function (node, parent) {
 t.getIds = function (node, map, ignoreTypes) {
   ignoreTypes = ignoreTypes || [];
 
-  var search = [node];
+  var search = [].concat(node);
   var ids    = {};
 
   while (search.length) {
@@ -185,14 +188,6 @@ t.getIds = function (node, map, ignoreTypes) {
   return ids;
 };
 
-t.isLet = function (node) {
-  return t.isVariableDeclaration(node) && (node.kind !== "var" || node._let);
-};
-
-t.isVar = function (node) {
-  return t.isVariableDeclaration(node, { kind: "var" }) && !node._let;
-};
-
 t.getIds.nodes = {
   AssignmentExpression: "left",
   ImportSpecifier: "id",
@@ -214,13 +209,32 @@ t.getIds.arrays = {
   ObjectPattern: "properties"
 };
 
+t.isLet = function (node) {
+  return t.isVariableDeclaration(node) && (node.kind !== "var" || node._let);
+};
+
+t.isVar = function (node) {
+  return t.isVariableDeclaration(node, { kind: "var" }) && !node._let;
+};
+
+t.removeComments = function (child) {
+  delete child.leadingComments;
+  delete child.trailingComments;
+  return child;
+};
+
+t.inheritsComments = function (child, parent) {
+  child.leadingComments  = _.compact([].concat(child.leadingComments, parent.leadingComments));
+  child.trailingComments = _.compact([].concat(child.trailingComments, parent.trailingComments));
+  return child;
+};
+
 t.inherits = function (child, parent) {
-  child.loc              = parent.loc;
-  child.end              = parent.end;
-  child.range            = parent.range;
-  child.start            = parent.start;
-  child.leadingComments  = parent.leadingComments;
-  child.trailingComments = parent.trailingComments;
+  child.loc   = parent.loc;
+  child.end   = parent.end;
+  child.range = parent.range;
+  child.start = parent.start;
+  t.inheritsComments(child, parent);
   return child;
 };
 

lib/6to5/util.js

@@ -106,8 +106,13 @@ exports.buildDefineProperties = function (mutatorMap) {
       if (key[0] === "_") return;
 
       node = _.clone(node);
+      var inheritNode = node;
       if (t.isMethodDefinition(node)) node = node.value;
-      mapNode.properties.push(t.property("init", t.identifier(key), node));
+
+      var prop = t.property("init", t.identifier(key), node);
+      t.inheritsComments(prop, inheritNode);
+      t.removeComments(inheritNode);
+      mapNode.properties.push(prop);
     });
 
     objExpr.properties.push(propNode);