Consolidate contiguous var declarations in destructuring transform

packages/babel-plugin-check-es2015-constants/test/fixtures/general/destructuring/expected.js

@@ -1,10 +1,10 @@
-var a = 1;
-var b = 2;
-var c = 3;
-var d = 4;
-var _e$f = { e: 5, f: 6 };
-var e = _e$f.e;
-var f = _e$f.f;
-var _a$b = { a: 7, b: 8 };
-var g = _a$b.a;
-var h = _a$b.b;
+var a = 1,
+    b = 2;
+var c = 3,
+    d = 4;
+var _e$f = { e: 5, f: 6 },
+    e = _e$f.e,
+    f = _e$f.f;
+var _a$b = { a: 7, b: 8 },
+    g = _a$b.a,
+    h = _a$b.b;

packages/babel-plugin-transform-es2015-destructuring/src/index.js

@@ -492,7 +492,21 @@ export default function ({ types: t }) {
           }
         }
 
-        path.replaceWithMultiple(nodes);
+        const nodesOut = [];
+        for (const node of nodes) {
+          const tail = nodesOut[nodesOut.length - 1];
+          if (tail && t.isVariableDeclaration(tail) && t.isVariableDeclaration(node) && tail.kind === node.kind) {
+            tail.declarations.push(...node.declarations);
+          } else {
+            nodesOut.push(node);
+          }
+        }
+
+        if (nodesOut.length === 1) {
+          path.replaceWith(nodesOut[0]);
+        } else {
+          path.replaceWithMultiple(nodesOut);
+        }
       }
     }
   };

packages/babel-plugin-transform-es2015-destructuring/test/fixtures/destructuring/array-unpack-optimisation/expected.js

@@ -1,36 +1,36 @@
-var a = 1;
-var b = 2;
-var a = 1;
-var b = 2;
-var a = 1;
-var b = 2;
-var c = [3, 4];
-var a = 1;
-var b = 2;
-var c = [3, 4];
-var _ref = [1, 2, 3];
-var a = _ref[0];
-var b = _ref[1];
-var _ref2 = [1, 2, 3];
-var a = _ref2[0];
-var b = _ref2[1];
-var _ref3 = [a, b];
-var a = _ref3[0];
-var b = _ref3[1];
+var a = 1,
+    b = 2;
+var a = 1,
+    b = 2;
+var a = 1,
+    b = 2,
+    c = [3, 4];
+var a = 1,
+    b = 2,
+    c = [3, 4];
+var _ref = [1, 2, 3],
+    a = _ref[0],
+    b = _ref[1];
+var _ref2 = [1, 2, 3],
+    a = _ref2[0],
+    b = _ref2[1];
+var _ref3 = [a, b],
+    a = _ref3[0],
+    b = _ref3[1];
 var _ref4 = [a[1], a[0]];
 a[0] = _ref4[0];
 a[1] = _ref4[1];
 
-var _ref5 = [].concat(babelHelpers.toConsumableArray(foo), [bar]);
+var _ref5 = [].concat(babelHelpers.toConsumableArray(foo), [bar]),
+    a = _ref5[0],
+    b = _ref5[1];
 
-var a = _ref5[0];
-var b = _ref5[1];
-var _ref6 = [foo(), bar];
-var a = _ref6[0];
-var b = _ref6[1];
-var _ref7 = [clazz.foo(), bar];
-var a = _ref7[0];
-var b = _ref7[1];
-var _ref8 = [clazz.foo, bar];
-var a = _ref8[0];
-var b = _ref8[1];
+var _ref6 = [foo(), bar],
+    a = _ref6[0],
+    b = _ref6[1];
+var _ref7 = [clazz.foo(), bar],
+    a = _ref7[0],
+    b = _ref7[1];
+var _ref8 = [clazz.foo, bar],
+    a = _ref8[0],
+    b = _ref8[1];

packages/babel-plugin-transform-es2015-destructuring/test/fixtures/destructuring/array/expected.js

@@ -1,7 +1,7 @@
-var a = "hello";
-var _ref = [", ", "junk"];
-var b = _ref[0];
-var c = "world";
+var a = "hello",
+    _ref = [", ", "junk"],
+    b = _ref[0],
+    c = "world";
 a = "hello";
 var _ref2 = [", ", "junk"];
 b = _ref2[0];

packages/babel-plugin-transform-es2015-destructuring/test/fixtures/destructuring/empty/expected.js

@@ -1,11 +1,7 @@
-var _ref = ["foo", "hello", [", ", "junk"], ["world"]];
-var a = _ref[1];
-
-var _ref$ = babelHelpers.slicedToArray(_ref[2], 1);
-
-var b = _ref$[0];
-
-var _ref$2 = babelHelpers.slicedToArray(_ref[3], 1);
-
-var c = _ref$2[0];
-var d = _ref[4];
+var _ref = ["foo", "hello", [", ", "junk"], ["world"]],
+    a = _ref[1],
+    _ref$ = babelHelpers.slicedToArray(_ref[2], 1),
+    b = _ref$[0],
+    _ref$2 = babelHelpers.slicedToArray(_ref[3], 1),
+    c = _ref$2[0],
+    d = _ref[4];

packages/babel-plugin-transform-es2015-destructuring/test/fixtures/destructuring/es7-object-rest/expected.js

@@ -1,11 +1,11 @@
 var z = {};
 var x = babelHelpers.objectWithoutProperties(z, []);
-var x = z.x;
-var y = babelHelpers.objectWithoutProperties(z, ["x"]);
-var x = z[x];
-var y = babelHelpers.objectWithoutProperties(z, [x]);
+var x = z.x,
+    y = babelHelpers.objectWithoutProperties(z, ["x"]);
+var x = z[x],
+    y = babelHelpers.objectWithoutProperties(z, [x]);
 
 (function (_ref) {
-  var x = _ref.x;
-  var y = babelHelpers.objectWithoutProperties(_ref, ["x"]);
+  var x = _ref.x,
+      y = babelHelpers.objectWithoutProperties(_ref, ["x"]);
 });

packages/babel-plugin-transform-es2015-destructuring/test/fixtures/destructuring/export-variable/expected.js

@@ -1,6 +1,6 @@
 var _ref = {};
-var a = _ref.a;
-var b = _ref.b;
+var a = _ref.a,
+    b = _ref.b;
 var _ref$c = _ref.c;
 var d = _ref$c.d;
 var _ref$c$e$f = _ref$c.e.f;

packages/babel-plugin-transform-es2015-destructuring/test/fixtures/destructuring/issue-3081/actual.js

@@ -0,0 +1,4 @@
+let list = [1, 2, 3, 4];
+for (let i = 0, { length } = list; i < length; i++) {
+  list[i];
+}

packages/babel-plugin-transform-es2015-destructuring/test/fixtures/destructuring/issue-3081/expected.js

@@ -0,0 +1,4 @@
+var list = [1, 2, 3, 4];
+for (var i = 0, length = list.length; i < length; i++) {
+  list[i];
+}

packages/babel-plugin-transform-es2015-destructuring/test/fixtures/destructuring/known-array/expected.js

@@ -1,3 +1,3 @@
 var z = [];
-var x = z[0];
-var y = z.slice(1);
+var x = z[0],
+    y = z.slice(1);

packages/babel-plugin-transform-es2015-destructuring/test/fixtures/destructuring/mixed/expected.js

@@ -1,11 +1,8 @@
 var rect = {};
 
-var _rect$topLeft = babelHelpers.slicedToArray(rect.topLeft, 2);
-
-var x1 = _rect$topLeft[0];
-var y1 = _rect$topLeft[1];
-
-var _rect$bottomRight = babelHelpers.slicedToArray(rect.bottomRight, 2);
-
-var x2 = _rect$bottomRight[0];
-var y2 = _rect$bottomRight[1];
+var _rect$topLeft = babelHelpers.slicedToArray(rect.topLeft, 2),
+    x1 = _rect$topLeft[0],
+    y1 = _rect$topLeft[1],
+    _rect$bottomRight = babelHelpers.slicedToArray(rect.bottomRight, 2),
+    x2 = _rect$bottomRight[0],
+    y2 = _rect$bottomRight[1];

packages/babel-plugin-transform-es2015-destructuring/test/fixtures/destructuring/multiple/expected.js

@@ -1,4 +1,4 @@
 var coords = [1, 2];
-var x = coords.x;
-var y = coords.y;
-var foo = "bar";
+var x = coords.x,
+    y = coords.y,
+    foo = "bar";

packages/babel-plugin-transform-es2015-destructuring/test/fixtures/destructuring/object-advanced/expected.js

@@ -1,10 +1,10 @@
 var rect = {};
-var _rect$topLeft = rect.topLeft;
-var x1 = _rect$topLeft.x;
-var y1 = _rect$topLeft.y;
-var _rect$bottomRight = rect.bottomRight;
-var x2 = _rect$bottomRight.x;
-var y2 = _rect$bottomRight.y;
-var _ref = [0, 1, 2, 3, 4, 5, 6];
-var foo = _ref[3];
-var bar = _ref[5];
+var _rect$topLeft = rect.topLeft,
+    x1 = _rect$topLeft.x,
+    y1 = _rect$topLeft.y,
+    _rect$bottomRight = rect.bottomRight,
+    x2 = _rect$bottomRight.x,
+    y2 = _rect$bottomRight.y;
+var _ref = [0, 1, 2, 3, 4, 5, 6],
+    foo = _ref[3],
+    bar = _ref[5];

packages/babel-plugin-transform-es2015-destructuring/test/fixtures/destructuring/object-basic/expected.js

@@ -1,3 +1,3 @@
 var coords = [1, 2];
-var x = coords.x;
-var y = coords.y;
+var x = coords.x,
+    y = coords.y;

packages/babel-plugin-transform-es2015-destructuring/test/fixtures/destructuring/parameters/expected.js

@@ -1,35 +1,33 @@
 function somethingAdvanced(_ref, p2, p3) {
   var _ref$topLeft = _ref.topLeft;
   _ref$topLeft = _ref$topLeft === undefined ? {} : _ref$topLeft;
-  var x1 = _ref$topLeft.x;
-  var y1 = _ref$topLeft.y;
-  var _ref$bottomRight = _ref.bottomRight;
+  var x1 = _ref$topLeft.x,
+      y1 = _ref$topLeft.y,
+      _ref$bottomRight = _ref.bottomRight;
   _ref$bottomRight = _ref$bottomRight === undefined ? {} : _ref$bottomRight;
-  var x2 = _ref$bottomRight.x;
-  var y2 = _ref$bottomRight.y;
+  var x2 = _ref$bottomRight.x,
+      y2 = _ref$bottomRight.y;
 }
 
 function unpackObject(_ref2) {
-  var title = _ref2.title;
-  var author = _ref2.author;
+  var title = _ref2.title,
+      author = _ref2.author;
 
   return title + " " + author;
 }
 
 console.log(unpackObject({ title: "title", author: "author" }));
 
 var unpackArray = function (_ref3, _ref4) {
-  var _ref6 = babelHelpers.slicedToArray(_ref3, 3);
-
-  var a = _ref6[0];
-  var b = _ref6[1];
-  var c = _ref6[2];
-
-  var _ref5 = babelHelpers.slicedToArray(_ref4, 3);
-
-  var x = _ref5[0];
-  var y = _ref5[1];
-  var z = _ref5[2];
+  var _ref6 = babelHelpers.slicedToArray(_ref3, 3),
+      a = _ref6[0],
+      b = _ref6[1],
+      c = _ref6[2];
+
+  var _ref5 = babelHelpers.slicedToArray(_ref4, 3),
+      x = _ref5[0],
+      y = _ref5[1],
+      z = _ref5[2];
 
   return a + b + c;
 };

packages/babel-plugin-transform-es2015-destructuring/test/fixtures/destructuring/spread/expected.js

@@ -1,10 +1,8 @@
 function isSorted(_ref) {
-  var _ref2 = babelHelpers.toArray(_ref);
-
-  var x = _ref2[0];
-  var y = _ref2[1];
-
-  var wow = _ref2.slice(2);
+  var _ref2 = babelHelpers.toArray(_ref),
+      x = _ref2[0],
+      y = _ref2[1],
+      wow = _ref2.slice(2);
 
   if (!zs.length) return true;
   if (y > x) return isSorted(zs);

packages/babel-plugin-transform-es2015-modules-commonjs/test/fixtures/regression/T7199/expected.js

@@ -8,8 +8,7 @@ var _foo2 = _interopRequireDefault(_foo);
 
 function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { 'default': obj }; }
 
-var _bar = bar;
-
-var _bar2 = _slicedToArray(_bar, 1);
+var _bar = bar,
+    _bar2 = _slicedToArray(_bar, 1);
 
 const x = _bar2[0];

packages/babel-plugin-transform-es2015-parameters/test/fixtures/parameters/destructuring-rest/expected.js

@@ -2,12 +2,12 @@
 function t() {
   var x = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : "default";
   var _ref = arguments[1];
-  var a = _ref.a;
-  var b = _ref.b;
+  var a = _ref.a,
+      b = _ref.b;
 
   for (var _len = arguments.length, args = Array(_len > 2 ? _len - 2 : 0), _key = 2; _key < _len; _key++) {
     args[_key - 2] = arguments[_key];
   }
 
   console.log(x, a, b, args);
-}
+}