Do not load unnecessary Babel 7 syntax plugins in Babel 8 (#16406)

babel · Apr 3, 2024 · 5a4fb2d · 5a4fb2d
1 parent fa9c005
commit 5a4fb2d
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Showing 7 changed files with 29 additions and 14 deletions.
diff --git a/...nsform-class-properties/test/fixtures/assumption-setPublicClassFields/foobar/options.json b/...nsform-class-properties/test/fixtures/assumption-setPublicClassFields/foobar/options.json
@@ -3,6 +3,5 @@
   "presets": [["env", { "targets": { "browsers": "ie 6" } }]],
   "assumptions": {
     "setPublicClassFields": true
-  },
-  "SKIP_babel7plugins_babel8core": "This test uses preset-env"
+  }
 }
diff --git a/...abel-plugin-transform-class-properties/test/fixtures/private/tagged-template/options.json b/...abel-plugin-transform-class-properties/test/fixtures/private/tagged-template/options.json
@@ -9,6 +9,5 @@
         }
       }
     ]
-  ],
-  "SKIP_babel7plugins_babel8core": "This test uses preset-env"
+  ]
 }
diff --git a/packages/babel-plugin-transform-class-properties/test/fixtures/public/foobar/options.json b/packages/babel-plugin-transform-class-properties/test/fixtures/public/foobar/options.json
@@ -1,5 +1,4 @@
 {
   "plugins": ["transform-class-properties"],
-  "presets": [["env", { "targets": { "browsers": "ie 6" } }]],
-  "SKIP_babel7plugins_babel8core": "This test uses preset-env"
+  "presets": [["env", { "targets": { "browsers": "ie 6" } }]]
 }
diff --git a/packages/babel-plugin-transform-class-properties/test/fixtures/regression/6154/options.json b/packages/babel-plugin-transform-class-properties/test/fixtures/regression/6154/options.json
@@ -1,5 +1,4 @@
 {
   "presets": [["env", { "targets": { "browsers": "ie 6" } }]],
-  "plugins": ["transform-class-properties"],
-  "SKIP_babel7plugins_babel8core": "This test uses preset-env"
+  "plugins": ["transform-class-properties"]
 }
diff --git a/packages/babel-preset-env/src/available-plugins.ts b/packages/babel-preset-env/src/available-plugins.ts
@@ -136,6 +136,8 @@ const availablePlugins = {
 };
 
 export const minVersions = {};
+// TODO(Babel 8): Remove this
+export let legacyBabel7SyntaxPlugins: Set<string>;
 
 if (!process.env.BABEL_8_BREAKING) {
   /* eslint-disable no-restricted-globals */
@@ -156,7 +158,7 @@ if (!process.env.BABEL_8_BREAKING) {
   // This is a factory to create a function that returns a no-op plugn
   const e = () => () => () => ({});
 
-  Object.assign(availablePlugins, {
+  const legacyBabel7SyntaxPluginsLoaders = {
     "syntax-async-generators":
       USE_ESM || IS_STANDALONE
         ? e()
@@ -217,15 +219,21 @@ if (!process.env.BABEL_8_BREAKING) {
       USE_ESM || IS_STANDALONE
         ? e()
         : () => require("@babel/plugin-syntax-top-level-await"),
-  });
+  };
 
   // This is a CJS plugin that depends on a package from the monorepo, so it
   // breaks using ESM. Given that ESM builds are new enough to have this
   // syntax enabled by default, we can safely skip enabling it.
   if (!USE_ESM) {
     // @ts-expect-error unknown key
-    availablePlugins["unicode-sets-regex"] = IS_STANDALONE
+    legacyBabel7SyntaxPluginsLoaders["unicode-sets-regex"] = IS_STANDALONE
       ? e()
       : () => require("@babel/plugin-syntax-unicode-sets-regex");
   }
+
+  Object.assign(availablePlugins, legacyBabel7SyntaxPluginsLoaders);
+
+  legacyBabel7SyntaxPlugins = new Set(
+    Object.keys(legacyBabel7SyntaxPluginsLoaders),
+  );
 }
diff --git a/packages/babel-preset-env/src/filter-items.ts b/packages/babel-preset-env/src/filter-items.ts
@@ -1,5 +1,5 @@
 import semver from "semver";
-import { minVersions } from "./available-plugins.ts";
+import { minVersions, legacyBabel7SyntaxPlugins } from "./available-plugins.ts";
 
 export function addProposalSyntaxPlugins(
   items: Set<string>,
@@ -31,6 +31,12 @@ export function removeUnsupportedItems(
       )
     ) {
       items.delete(item);
+    } else if (
+      !process.env.BABEL_8_BREAKING &&
+      babelVersion[0] === "8" &&
+      legacyBabel7SyntaxPlugins.has(item)
+    ) {
+      items.delete(item);
     }
   });
 }
diff --git a/packages/babel-preset-env/src/index.ts b/packages/babel-preset-env/src/index.ts
@@ -117,6 +117,7 @@ export const transformIncludesAndExcludes = (opts: Array<string>): any => {
 function getSpecialModulesPluginNames(
   modules: Exclude<ModuleOption, "auto">,
   shouldTransformDynamicImport: boolean,
+  babelVersion: string,
 ) {
   const modulesPluginNames = [];
   if (modules) {
@@ -134,7 +135,7 @@ function getSpecialModulesPluginNames(
     }
   }
 
-  if (!process.env.BABEL_8_BREAKING) {
+  if (!process.env.BABEL_8_BREAKING && babelVersion[0] !== "8") {
     // Enable module-related syntax plugins for older Babel versions
     if (!shouldTransformDynamicImport) {
       modulesPluginNames.push("syntax-dynamic-import");
@@ -419,7 +420,11 @@ option \`forceAllTransforms: true\` instead.
     include.plugins,
     exclude.plugins,
     transformTargets,
-    getSpecialModulesPluginNames(modules, shouldTransformDynamicImport),
+    getSpecialModulesPluginNames(
+      modules,
+      shouldTransformDynamicImport,
+      api.version,
+    ),
     process.env.BABEL_8_BREAKING || !loose
       ? undefined
       : ["transform-typeof-symbol"],