Merged in wbinnssmith/live-reexports (pull request #5)

Live reexports fix

Approved-by: Maia Teegarden

packages/core/integration-tests/test/integration/scope-hoisting/es6/live-bindings-cross-bundle/a.html

@@ -0,0 +1 @@
+<script src="a.js"></script>

packages/core/integration-tests/test/integration/scope-hoisting/es6/live-bindings-cross-bundle/a.js

@@ -0,0 +1,4 @@
+import "./library/a.js";
+import { a } from "./library/index.js";
+
+output = a;

packages/core/integration-tests/test/integration/scope-hoisting/es6/live-bindings-cross-bundle/b.html

@@ -0,0 +1 @@
+<script src="b.js"></script>

packages/core/integration-tests/test/integration/scope-hoisting/es6/live-bindings-cross-bundle/b.js

@@ -0,0 +1,4 @@
+import "./library/a.js";
+import { a } from "./library/index.js";
+
+output = a;

packages/core/integration-tests/test/integration/scope-hoisting/es6/live-bindings-cross-bundle/library/a.js

@@ -0,0 +1,2 @@
+import { b } from "./index.js";
+export var a = "aaa";

packages/core/integration-tests/test/integration/scope-hoisting/es6/live-bindings-cross-bundle/library/b.js

@@ -0,0 +1 @@
+export var b = "bbb";

packages/core/integration-tests/test/integration/scope-hoisting/es6/live-bindings-cross-bundle/library/index.js

@@ -0,0 +1,2 @@
+export { a } from "./a.js";
+export { b } from "./b.js";

packages/core/integration-tests/test/integration/scope-hoisting/es6/live-bindings-cross-bundle/package.json

@@ -0,0 +1,5 @@
+{
+ "@parcel/bundler-default": {
+ "minBundleSize": 0
+ }
+}

packages/core/integration-tests/test/integration/scope-hoisting/es6/live-bindings-reexports-namespace/a.js

@@ -0,0 +1,11 @@
+import * as x from "./b.js";
+
+function get(obj, prop) {
+ return obj[prop];
+}
+
+let a = get(x, "v");
+get(x, "update")();
+let b = get(x, "v");
+
+output = [a, b];

packages/core/integration-tests/test/integration/scope-hoisting/es6/live-bindings-reexports-namespace/b.js

@@ -0,0 +1 @@
+export {v, update} from "./c.js";

packages/core/integration-tests/test/integration/scope-hoisting/es6/live-bindings-reexports-namespace/c.js

@@ -0,0 +1,4 @@
+export let v = 1;
+export function update() {
+ v++;
+}

packages/core/integration-tests/test/scope-hoisting.js

@@ -441,6 +441,36 @@ describe('scope hoisting', function() {
  assert.equal(output, 8);
  });
 
+ it('supports live bindings in namespaces of reexporting assets', async function() {
+ let b = await bundle(
+ path.join(
+ __dirname,
+ '/integration/scope-hoisting/es6/live-bindings-reexports-namespace/a.js',
+ ),
+ );
+
+ let output = await run(b);
+ assert.deepEqual(output, [1, 2]);
+ });
+
+ it('supports live bindings across bundles', async function() {
+ let b = await bundle(
+ ['a.html', 'b.html'].map(f =>
+ path.join(
+ __dirname,
+ '/integration/scope-hoisting/es6/live-bindings-cross-bundle',
+ f,
+ ),
+ ),
+ );
+
+ let output = await runBundle(
+ b,
+ b.getBundles().find(b => b.type === 'html'),
+ );
+ assert.strictEqual(output, 'aaa');
+ });
+
  it('supports dynamic import syntax for code splitting', async function() {
  let b = await bundle(
  path.join(

packages/shared/scope-hoisting/src/helpers.js

@@ -6,6 +6,10 @@ function $parcel$defineInteropFlag(a) {
  Object.defineProperty(a, '__esModule', {value: true});
 }
 
+function $parcel$reexport(e, n, v) {
+ Object.defineProperty(e, n, {get: v, enumerable: true});
+}
+
 function $parcel$exportWildcard(dest, source) {
  Object.keys(source).forEach(function(key) {
  if (key === 'default' || key === '__esModule') {

packages/shared/scope-hoisting/src/hoist.js

@@ -59,6 +59,10 @@ const EXPORT_ASSIGN_TEMPLATE = template.statement<
  {|EXPORTS: Identifier, NAME: Identifier, LOCAL: Expression|},
  Statement,
 >('EXPORTS.NAME = LOCAL;');
+const REEXPORT_TEMPLATE = template.statement<
+ {|EXPORTS: Identifier, NAME: StringLiteral, LOCAL: Expression|},
+ Statement,
+>('$parcel$reexport(EXPORTS, NAME, function(){return LOCAL;});');
 const EXPORT_ALL_TEMPLATE = template.statement<
  {|OLD_NAME: Identifier, ID: StringLiteral, SOURCE: StringLiteral|},
  Statement,
@@ -647,9 +651,9 @@ const VISITOR: Visitor<MutableAsset> = {
 
  id.loc = specifier.loc;
  path.insertAfter(
- EXPORT_ASSIGN_TEMPLATE({
+ REEXPORT_TEMPLATE({
  EXPORTS: getExportsIdentifier(asset, path.scope),
- NAME: exported,
+ NAME: t.stringLiteral(exported.name),
  LOCAL: id,
  }),
  );

packages/shared/scope-hoisting/src/shake.js

@@ -81,7 +81,10 @@ function getUnusedBinding(path, name, exportsMap) {
 
  // Is there any references which aren't simple assignments?
  let bailout = binding.referencePaths.some(
- path => !isExportAssignment(path, exportsMap) && !isWildcardDest(path),
+ path =>
+ !isExportAssignment(path, exportsMap) &&
+ !isWildcardDest(path) &&
+ !isReexportDest(path),
  );
 
  if (!bailout) {
@@ -154,6 +157,17 @@ function isWildcardDest(path) {
  );
 }
 
+// check if the argument appears as $parcel$reexport(path, ...)
+function isReexportDest(path) {
+ let parent: Node = path.parent;
+
+ return (
+ isCallExpression(parent) &&
+ isIdentifier(parent.callee, {name: '$parcel$reexport'}) &&
+ parent.arguments[0] === path.node
+ );
+}
+
 function remove(
  path: NodePath<Node>,
  scope: Scope,
@@ -200,6 +214,8 @@ function remove(
  );
  remove(path.parentPath, scope, exportsMap);
  }
+ } else if (isReexportDest(path)) {
+ remove(path.parentPath, scope, exportsMap);
  } else if (!path.removed) {
  if (isSequenceExpression(parent) && parent.expressions.length === 1) {
  // TODO missing test coverage