Merge pull request #3103 from amasad/spacing

Respect spacing in compact mode

packages/babel-generator/src/generators/expressions.js

@@ -141,7 +141,9 @@ export function ExpressionStatement(node: Object) {
 
 export function AssignmentPattern(node: Object) {
   this.print(node.left, node);
-  this.push(" = ");
+  this.space();
+  this.push("=");
+  this.space();
   this.print(node.right, node);
 }
 
@@ -158,7 +160,6 @@ export function AssignmentExpression(node: Object, parent: Object) {
   this.print(node.left, node);
 
   let spaces = !this.format.compact || node.operator === "in" || node.operator === "instanceof";
-  spaces = true; // todo: https://github.com/babel/babel/issues/1835
   if (spaces) this.push(" ");
 
   this.push(node.operator);
@@ -168,7 +169,11 @@ export function AssignmentExpression(node: Object, parent: Object) {
     // http://javascript.spec.whatwg.org/#comment-syntax
     spaces = node.operator === "<" &&
              t.isUnaryExpression(node.right, { prefix: true, operator: "!" }) &&
-             t.isUnaryExpression(node.right.argument, { prefix: true, operator: "--" });
+             t.isUnaryExpression(node.right.argument, { prefix: true, operator: "--" }) ||
+             // Need spaces for operators of the same kind to avoid: `a+++b`
+             t.isUnaryExpression(node.right, { prefix: true, operator: node.operator }) ||
+             t.isUpdateExpression(node.right, { prefix: true, operator: node.operator + node.operator });
+
   }
 
   if (spaces) this.push(" ");

packages/babel-generator/src/printer.js

@@ -146,6 +146,7 @@ export default class Printer extends Buffer {
 
   printBlock(parent) {
     let node = parent.body;
+
     if (!t.isEmptyStatement(node)) {
       this.space();
     }

packages/babel-generator/test/fixtures/compact/assignment/actual.js

@@ -0,0 +1,2 @@
+x = 1;
+var { y = 1 } = obj;

packages/babel-generator/test/fixtures/compact/assignment/expected.js

@@ -0,0 +1 @@
+x=1;var {y=1}=obj;

packages/babel-generator/test/fixtures/compact/binary-expressions/actual.js

@@ -0,0 +1,4 @@
+1 * 1;
+1 && 1;
+1 + +1;
+x + ++y;

packages/babel-generator/test/fixtures/compact/binary-expressions/expected.js

@@ -0,0 +1 @@
+1*1;1&&1;1+ +1;x+ ++y;

packages/babel-generator/test/fixtures/compact/while/actual.js

@@ -0,0 +1 @@
+while(true) x();

packages/babel-generator/test/fixtures/compact/while/expected.js

@@ -0,0 +1 @@
+while(true)x();