From 1bbf109e8eb6ba6520d28ac6762e354d5ee46311 Mon Sep 17 00:00:00 2001
From: Logan Smyth <loganfsmyth@gmail.com>
Date: Sat, 16 Jul 2016 17:34:15 -0700
Subject: [PATCH] Move aux comments entirely into printer.

---
 .../src/generators/expressions.js             |  1 -
 packages/babel-generator/src/index.js         |  5 +--
 packages/babel-generator/src/printer.js       | 37 +++++++++++--------
 .../auxiliary-comment/overview/expected.js    | 10 ++---
 4 files changed, 28 insertions(+), 25 deletions(-)

diff --git a/packages/babel-generator/src/generators/expressions.js b/packages/babel-generator/src/generators/expressions.js
index 72e7f4ac9c..0c2ca52cbd 100644
--- a/packages/babel-generator/src/generators/expressions.js
+++ b/packages/babel-generator/src/generators/expressions.js
@@ -95,7 +95,6 @@ function commaSeparatorNewline() {
 
 export function CallExpression(node: Object) {
   this.print(node.callee, node);
-  if (node.loc) this.printAuxAfterComment();
 
   this.token("(");
 
diff --git a/packages/babel-generator/src/index.js b/packages/babel-generator/src/index.js
index 124789ef28..5b106a401b 100644
--- a/packages/babel-generator/src/index.js
+++ b/packages/babel-generator/src/index.js
@@ -30,10 +30,7 @@ class Generator extends Printer {
    */
 
   generate() {
-    this.print(this.ast);
-    this.printAuxAfterComment();
-
-    return this._buf.get();
+    return super.generate(this.ast);
   }
 }
 
diff --git a/packages/babel-generator/src/printer.js b/packages/babel-generator/src/printer.js
index da81052b05..0ab1998be4 100644
--- a/packages/babel-generator/src/printer.js
+++ b/packages/babel-generator/src/printer.js
@@ -33,18 +33,25 @@ export default class Printer {
   }
 
   format: Format;
-  insideAux: boolean = false;
   inForStatementInitCounter: number = 0;
 
   _buf: Buffer;
   _whitespace: Whitespace;
   _printStack: Array<Node> = [];
   _indent: number = 0;
+  _insideAux: boolean = false;
   _printedCommentStarts: Object = {};
   _parenPushNewlineState: ?Object = null;
   _printAuxAfterOnNextUserNode: boolean = false;
   _printedComments: WeakSet = new WeakSet();
 
+  generate(ast) {
+    this.print(ast);
+    this._maybeAddAuxComment();
+
+    return this._buf.get();
+  }
+
   /**
    * Increment indent size.
    */
@@ -70,6 +77,7 @@ export default class Printer {
    */
 
   semicolon(force: boolean = false): void {
+    this._maybeAddAuxComment();
     this._append(";", !force /* queue */);
   }
 
@@ -112,6 +120,7 @@ export default class Printer {
   word(str: string): void {
     if (this._endsWithWord) this._space();
 
+    this._maybeAddAuxComment();
     this._append(str);
 
     this._endsWithWord = true;
@@ -133,6 +142,7 @@ export default class Printer {
       this._space();
     }
 
+    this._maybeAddAuxComment();
     this._append(str);
   }
 
@@ -296,10 +306,9 @@ export default class Printer {
 
     this._printStack.push(node);
 
-    let oldInAux = this.insideAux;
-    this.insideAux = !node.loc;
-    if (!this.insideAux) this.printAuxAfterComment();
-    else if (!oldInAux) this._printAuxBeforeComment();
+    let oldInAux = this._insideAux;
+    this._insideAux = !node.loc;
+    this._maybeAddAuxComment(this._insideAux && !oldInAux);
 
     let needsParens = n.needsParens(node, parent, this._printStack);
     if (needsParens) this.token("(");
@@ -311,9 +320,6 @@ export default class Printer {
       this[node.type](node, parent);
     });
 
-    // Check again if any of our children may have left an aux comment on the stack
-    if (!this.insideAux) this.printAuxAfterComment();
-
     this._printTrailingComments(node, parent);
 
     if (needsParens) this.token(")");
@@ -322,7 +328,12 @@ export default class Printer {
     this._printStack.pop();
 
     this.format.concise = oldConcise;
-    this.insideAux = oldInAux;
+    this._insideAux = oldInAux;
+  }
+
+  _maybeAddAuxComment(enteredPositionlessNode) {
+    if (enteredPositionlessNode) this._printAuxBeforeComment();
+    if (!this._insideAux) this._printAuxAfterComment();
   }
 
   _printAuxBeforeComment() {
@@ -338,7 +349,7 @@ export default class Printer {
     }
   }
 
-  printAuxAfterComment() {
+  _printAuxAfterComment() {
     if (!this._printAuxAfterOnNextUserNode) return;
     this._printAuxAfterOnNextUserNode = false;
 
@@ -381,10 +392,6 @@ export default class Printer {
         opts.iterator(node, i);
       }
 
-      if (opts.separator && parent.loc) {
-        this.printAuxAfterComment();
-      }
-
       if (opts.separator && i < nodes.length - 1) {
         opts.separator.call(this);
       }
@@ -527,7 +534,7 @@ export default class Printer {
       }
 
       //
-      this.token(val);
+      this._append(val);
 
       // whitespace after
       this.newline((this._whitespace ? this._whitespace.getNewlinesAfter(comment) : 0) +
diff --git a/packages/babel-plugin-transform-es2015-modules-commonjs/test/fixtures/auxiliary-comment/overview/expected.js b/packages/babel-plugin-transform-es2015-modules-commonjs/test/fixtures/auxiliary-comment/overview/expected.js
index 7c0eb1860c..3ea207e748 100644
--- a/packages/babel-plugin-transform-es2015-modules-commonjs/test/fixtures/auxiliary-comment/overview/expected.js
+++ b/packages/babel-plugin-transform-es2015-modules-commonjs/test/fixtures/auxiliary-comment/overview/expected.js
@@ -5,11 +5,11 @@ Object.defineProperty(exports, "__esModule", {
 });
 exports.test = undefined;
 
-/*after*/ /*before*/require("foo"); /*after*/
+/*after*/ /*before*/require("foo") /*after*/;
 
-/*before*/require("foo-bar"); /*after*/
+/*before*/require("foo-bar") /*after*/;
 
-/*before*/require("./directory/foo-bar"); /*after*/
+/*before*/require("./directory/foo-bar") /*after*/;
 
 var /*before*/_foo = require("foo2") /*after*/;
 
@@ -29,5 +29,5 @@ var test = /*before*/exports. /*after*/test = 5;
 /*before*/(0, _foo4.bar) /*after*/( /*before*/_foo2.default /*after*/, /*before*/_foo5.foo /*after*/);
 
 /* my comment */
-/*before*/_foo5.foo; /*after*/
-/*before*/_foo2.default; /*after*/
+/*before*/_foo5.foo /*after*/;
+/*before*/_foo2.default /*after*/;