intermediate packages

build-system/babel-config/bento-element-config.js

@@ -1,5 +1,39 @@
+const bentoRuntimePackages = require('../compile/generate/metadata/bento-runtime-packages');
+const {generateIntermediatePackage} = require('../compile/generate/bento');
 const {getMinifiedConfig} = require('./minified-config');
 const {getUnminifiedConfig} = require('./unminified-config');
+const {outputFileSync, pathExistsSync} = require('fs-extra');
+
+/**
+ * @param {string} original
+ * @param {string[]} names
+ * @return {string}
+ */
+function writeIntermediatePackage(original, names) {
+  const basename = original.replace(/[^a-z0-9]/g, '_');
+  const filePath = `build/bento-package/${basename}.js`;
+  if (!pathExistsSync(filePath)) {
+    outputFileSync(filePath, generateIntermediatePackage(original, names));
+  }
+  // #build is an alias to the root build/
+  return `#${filePath}`;
+}
+
+/**
+ * @return {[string, {packages: {[original: string]: {pkg: string, names: string[]}}}]}
+ */
+function getImportPlugin() {
+  const packages = Object.fromEntries(
+    Object.entries(bentoRuntimePackages).map(([original, names]) => {
+      const pkg = writeIntermediatePackage(original, names);
+      return [original, {pkg, names}];
+    })
+  );
+  return [
+    './build-system/babel-plugins/babel-plugin-bento-imports',
+    {packages},
+  ];
+}
 
 /**
  * @param {!Object} config
@@ -8,10 +42,7 @@ const {getUnminifiedConfig} = require('./unminified-config');
 function mergeWithConfig(config) {
   return {
     ...config,
-    plugins: [
-      './build-system/babel-plugins/babel-plugin-bento-imports',
-      ...config.plugins,
-    ],
+    plugins: [getImportPlugin(), ...config.plugins],
   };
 }
 

build-system/babel-plugins/babel-plugin-bento-imports/index.js

@@ -1,12 +1,11 @@
 /**
  * @fileoverview
- * Replaces `import` statements of listed modules with `const` statements.
- * These reference the global `BENTO` which is meant to provide the contents of
- * these listed modules.
+ * Replaces `import` statements of listed module specifiers with a different
+ * module.
+ * This is similar to `module-resolver`, except that it preserves specifiers to
+ * the original package if a specific name is not listed.
  */
 
-const bentoRuntimePackages = require('../../compile/generate/metadata/bento-runtime-packages');
-
 module.exports = function (babel) {
   const {types: t} = babel;
 
@@ -27,32 +26,22 @@ module.exports = function (babel) {
 
   const visitor = {
     ImportDeclaration(path, state) {
-      // Options for tests
-      const packages = state.opts.packages || bentoRuntimePackages;
+      const {packages} = state.opts;
 
       const source = path.node.source.value;
-      const names = packages[source];
-      if (!names) {
+      const def = packages[source];
+      if (!def) {
         return;
       }
 
+      const {names, pkg} = def;
       const preservedSpecifiers = [];
       const statements = path.node.specifiers.map((node) => {
-        // Full object reference for namespace imports
-        // - import * as p from 'package';
-        // + const p = {'x': BENTO['package']['x'], ...}
         if (t.isImportNamespaceSpecifier(node)) {
-          const properties = names
-            .map((name) => `'${name}': PKG['${name}']`)
-            .join(',');
-          return `const ${node.local.name} = {${properties}}`;
+          return `import * as ${node.local.name} from '${pkg}';`;
         }
-        // One statement per named import
-        // - import {z, y} from 'package';
-        // + const z = BENTO['package']['z'];
-        // + const y = BENTO['package']['y'];
         if (t.isImportSpecifier(node) && names.includes(node.imported.name)) {
-          return `const ${node.local.name} = PKG['${node.imported.name}']`;
+          return `import {${node.imported.name} as ${node.local.name}} from '${pkg}';`;
         }
         preservedSpecifiers.push(node);
       });
@@ -62,13 +51,8 @@ module.exports = function (babel) {
         return;
       }
 
-      const template = statements.filter(Boolean).join(';\n');
-
-      const declaration = babel.template(template)({
-        // We need to specify a placeholder key because babel's `template` will
-        // fail with unspecified UPPERCASE identifiers.
-        'PKG': `BENTO[${JSON.stringify(source)}]`,
-      });
+      const template = statements.filter(Boolean).join('\n');
+      const declaration = babel.template(template)();
 
       // Insert below this sequence of ImportDeclarations
       getLastInSequenceOfType(path).insertAfter(declaration);

build-system/babel-plugins/babel-plugin-bento-imports/test/fixtures/transform-assertions/local-name/output.mjs

@@ -1,3 +1,3 @@
-const a = BENTO["~foo"]['a'];
-const b = BENTO["~foo"]['b'];
-const x = BENTO["~foo"]['c'];
+import { a } from '#build/overridden_foo';
+import { b } from '#build/overridden_foo';
+import { c as x } from '#build/overridden_foo';

build-system/babel-plugins/babel-plugin-bento-imports/test/fixtures/transform-assertions/mixed/output.mjs

@@ -1,8 +1,4 @@
 import { __unlistedShouldBePreserved } from '~bar/baz';
 import { ignored } from './unlisted';
-const fooBar = BENTO["~bar/baz"]['fooBar'];
-const foo = {
-  'a': BENTO["~foo"]['a'],
-  'b': BENTO["~foo"]['b'],
-  'c': BENTO["~foo"]['c']
-};
+import * as foo from '#build/overridden_foo';
+import { fooBar } from '#build/overridden_bar_baz';

build-system/babel-plugins/babel-plugin-bento-imports/test/fixtures/transform-assertions/namespace/output.mjs

@@ -1,5 +1 @@
-const foo = {
-  'a': BENTO["~foo"]['a'],
-  'b': BENTO["~foo"]['b'],
-  'c': BENTO["~foo"]['c']
-};
+import * as foo from '#build/overridden_foo';

build-system/babel-plugins/babel-plugin-bento-imports/test/fixtures/transform-assertions/options.json

@@ -0,0 +1,25 @@
+{
+  "plugins": [
+    [
+      "../../..",
+      {
+        "packages": {
+          "~foo": {
+            "pkg": "#build/overridden_foo",
+            "names": [
+              "a",
+              "b",
+              "c"
+            ]
+          },
+          "~bar/baz": {
+            "pkg": "#build/overridden_bar_baz",
+            "names": [
+              "fooBar"
+            ]
+          }
+        }
+      }
+    ]
+  ]
+}

build-system/babel-plugins/babel-plugin-bento-imports/test/fixtures/transform-assertions/preserved/output.mjs

@@ -1,2 +1,2 @@
 import { __unlistedShouldBePreserved } from '~foo';
-const a = BENTO["~foo"]['a'];
+import { a } from '#build/overridden_foo';

build-system/compile/compile.js

@@ -39,7 +39,6 @@ const MAX_PARALLEL_CLOSURE_INVOCATIONS =
  *  noAddDeps?: boolean,
  *  continueOnError?: boolean,
  *  errored?: boolean,
- *  babelCaller?: string,
  * }}
  */
 let OptionsDef;
@@ -138,9 +137,6 @@ function getSrcs(entryModuleFilenames, options) {
           .split(path.win32.sep)
           .join(path.posix.sep)
       );
-    } else {
-      // Ensure that entrypoint itself is listed.
-      srcs.push(filename);
     }
   });
   if (options.extraGlobs) {

build-system/compile/generate/bento.js

@@ -59,6 +59,18 @@ function generateBentoRuntime(packages = bentoRuntimePackages) {
   `);
 }
 
+/**
+ * @param {string} original
+ * @param {string[]} names
+ * @return {?string}
+ */
+function generateIntermediatePackage(original, names) {
+  return names
+    .map((name) => `export const ${name} = BENTO['${original}'].${name};`)
+    .join('\n');
+}
+
 module.exports = {
   generateBentoRuntime,
+  generateIntermediatePackage,
 };