Load .browserslistrc when using old @babel/core versions

packages/babel-preset-env/package.json

@@ -90,6 +90,7 @@
   },
   "devDependencies": {
     "@babel/core": "workspace:*",
+    "@babel/core-7.12": "npm:@babel/core@7.12.9",
     "@babel/helper-plugin-test-runner": "workspace:*",
     "@babel/plugin-syntax-dynamic-import": "^7.8.3"
   }

packages/babel-preset-env/src/index.js

@@ -1,6 +1,6 @@
 //@flow
 
-import { SemVer } from "semver";
+import { SemVer, lt } from "semver";
 import { logPluginOrPolyfill } from "./debug";
 import getOptionSpecificExcludesFor from "./get-option-specific-excludes";
 import { removeUnnecessaryItems } from "./filter-items";
@@ -295,6 +295,10 @@ export default declare((api, opts) => {
   let targets = babelTargets;
 
   if (
+    // @babel/core < 7.13.0 doesn't load targets (api.targets() always
+    // returns {} thanks to @babel/helper-plugin-utils), so we always want
+    // to fallback to the old targets behavior in this case.
+    lt(api.version, "7.13.0") ||
     // If any browserslist-related option is specified, fallback to the old
     // behavior of not using the targets specified in the top-level options.
     opts.targets ||

packages/babel-preset-env/test/regressions.js

@@ -0,0 +1,22 @@
+import * as babel7_12 from "@babel/core";
+import env from "..";
+import path from "path";
+
+describe("#12880", () => {
+  it("read the .browserslistrc file when using @babel/core < 7.13.0", () => {
+    // The browserslistrc file contains "firefox 50".
+    // a ** b is supported starting from firefox 52;
+    // a => b is supported starting from firefox 45.
+    const out = babel7_12.transformSync("a ** b; a => b;", {
+      configFile: false,
+      presets: [[env, { modules: false }]],
+      filename: path.join(__dirname, "regressions", "input.js"),
+    });
+
+    expect(out.code).toMatchInlineSnapshot(`
+      "Math.pow(a, b);
+
+      a => b;"
+    `);
+  });
+});

packages/babel-preset-env/test/regressions/.browserslistrc

@@ -0,0 +1 @@
+firefox 50

yarn.lock

@@ -150,6 +150,30 @@ __metadata:
   languageName: unknown
   linkType: soft
 
+"@babel/core-7.12@npm:@babel/core@7.12.9":
+  version: 7.12.9
+  resolution: "@babel/core@npm:7.12.9"
+  dependencies:
+    "@babel/code-frame": ^7.10.4
+    "@babel/generator": ^7.12.5
+    "@babel/helper-module-transforms": ^7.12.1
+    "@babel/helpers": ^7.12.5
+    "@babel/parser": ^7.12.7
+    "@babel/template": ^7.12.7
+    "@babel/traverse": ^7.12.9
+    "@babel/types": ^7.12.7
+    convert-source-map: ^1.7.0
+    debug: ^4.1.0
+    gensync: ^1.0.0-beta.1
+    json5: ^2.1.2
+    lodash: ^4.17.19
+    resolve: ^1.3.2
+    semver: ^5.4.1
+    source-map: ^0.5.0
+  checksum: beefb9f490cfff7cafc02e5a11148297a71260ee18f5fdf6e14bf5694bc28431eec3813a91d0f0fc8c6122c5133d90d3261dadf45cb914d7d340a5b3077fd9bd
+  languageName: node
+  linkType: hard
+
 "@babel/core@npm:7.13.1, @babel/core@npm:^7.1.0, @babel/core@npm:^7.13.1, @babel/core@npm:^7.7.5":
   version: 7.13.1
   resolution: "@babel/core@npm:7.13.1"
@@ -285,7 +309,7 @@ __metadata:
   languageName: unknown
   linkType: soft
 
-"@babel/generator@npm:^7.13.0":
+"@babel/generator@npm:^7.12.5, @babel/generator@npm:^7.13.0":
   version: 7.13.0
   resolution: "@babel/generator@npm:7.13.0"
   dependencies:
@@ -617,7 +641,7 @@ __metadata:
   languageName: unknown
   linkType: soft
 
-"@babel/helper-module-transforms@npm:^7.12.13, @babel/helper-module-transforms@npm:^7.13.0":
+"@babel/helper-module-transforms@npm:^7.12.1, @babel/helper-module-transforms@npm:^7.12.13, @babel/helper-module-transforms@npm:^7.13.0":
   version: 7.13.0
   resolution: "@babel/helper-module-transforms@npm:7.13.0"
   dependencies:
@@ -855,7 +879,7 @@ __metadata:
   languageName: unknown
   linkType: soft
 
-"@babel/helpers@npm:^7.13.0":
+"@babel/helpers@npm:^7.12.5, @babel/helpers@npm:^7.13.0":
   version: 7.13.0
   resolution: "@babel/helpers@npm:7.13.0"
   dependencies:
@@ -924,7 +948,7 @@ __metadata:
   languageName: unknown
   linkType: soft
 
-"@babel/parser@npm:^7.0.0, @babel/parser@npm:^7.12.13, @babel/parser@npm:^7.13.0":
+"@babel/parser@npm:^7.0.0, @babel/parser@npm:^7.12.13, @babel/parser@npm:^7.12.7, @babel/parser@npm:^7.13.0":
   version: 7.13.4
   resolution: "@babel/parser@npm:7.13.4"
   bin:
@@ -3037,6 +3061,7 @@ __metadata:
   dependencies:
     "@babel/compat-data": "workspace:^7.13.8"
     "@babel/core": "workspace:*"
+    "@babel/core-7.12": "npm:@babel/core@7.12.9"
     "@babel/helper-compilation-targets": "workspace:^7.13.8"
     "@babel/helper-plugin-test-runner": "workspace:*"
     "@babel/helper-plugin-utils": "workspace:^7.13.0"
@@ -3367,7 +3392,7 @@ __metadata:
   languageName: unknown
   linkType: soft
 
-"@babel/template@npm:^7.12.13, @babel/template@npm:^7.3.3":
+"@babel/template@npm:^7.12.13, @babel/template@npm:^7.12.7, @babel/template@npm:^7.3.3":
   version: 7.12.13
   resolution: "@babel/template@npm:7.12.13"
   dependencies:
@@ -3398,7 +3423,7 @@ __metadata:
   languageName: unknown
   linkType: soft
 
-"@babel/traverse@npm:^7.0.0, @babel/traverse@npm:^7.1.0, @babel/traverse@npm:^7.13.0":
+"@babel/traverse@npm:^7.0.0, @babel/traverse@npm:^7.1.0, @babel/traverse@npm:^7.12.9, @babel/traverse@npm:^7.13.0":
   version: 7.13.0
   resolution: "@babel/traverse@npm:7.13.0"
   dependencies:
@@ -3432,7 +3457,7 @@ __metadata:
   languageName: unknown
   linkType: soft
 
-"@babel/types@npm:^7.0.0, @babel/types@npm:^7.12.1, @babel/types@npm:^7.12.13, @babel/types@npm:^7.13.0, @babel/types@npm:^7.3.3, @babel/types@npm:^7.4.4":
+"@babel/types@npm:^7.0.0, @babel/types@npm:^7.12.1, @babel/types@npm:^7.12.13, @babel/types@npm:^7.12.7, @babel/types@npm:^7.13.0, @babel/types@npm:^7.3.3, @babel/types@npm:^7.4.4":
   version: 7.13.0
   resolution: "@babel/types@npm:7.13.0"
   dependencies:
@@ -8370,7 +8395,7 @@ fsevents@^1.2.7:
   languageName: node
   linkType: hard
 
-"gensync@npm:^1.0.0-beta.2":
+"gensync@npm:^1.0.0-beta.1, gensync@npm:^1.0.0-beta.2":
   version: 1.0.0-beta.2
   resolution: "gensync@npm:1.0.0-beta.2"
   checksum: d523437689c97b3aba9c5cdeca4677d5fff9a29d620db693fea40d852bad63563110f16979d0170248439dbcd2ecee0780fb2533d3f0519f019081aa10767c60
@@ -12820,7 +12845,7 @@ fsevents@^1.2.7:
   languageName: node
   linkType: hard
 
-"resolve@^1.1.4, resolve@^1.1.6, resolve@^1.1.7, resolve@^1.10.0, resolve@^1.13.1, resolve@^1.14.2, resolve@^1.17.0, resolve@^1.18.1, resolve@^1.19.0, resolve@^1.4.0, resolve@^1.9.0":
+"resolve@^1.1.4, resolve@^1.1.6, resolve@^1.1.7, resolve@^1.10.0, resolve@^1.13.1, resolve@^1.14.2, resolve@^1.17.0, resolve@^1.18.1, resolve@^1.19.0, resolve@^1.3.2, resolve@^1.4.0, resolve@^1.9.0":
   version: 1.20.0
   resolution: "resolve@npm:1.20.0"
   dependencies:
@@ -12830,7 +12855,7 @@ fsevents@^1.2.7:
   languageName: node
   linkType: hard
 
-"resolve@patch:resolve@^1.1.4#builtin<compat/resolve>, resolve@patch:resolve@^1.1.6#builtin<compat/resolve>, resolve@patch:resolve@^1.1.7#builtin<compat/resolve>, resolve@patch:resolve@^1.10.0#builtin<compat/resolve>, resolve@patch:resolve@^1.13.1#builtin<compat/resolve>, resolve@patch:resolve@^1.14.2#builtin<compat/resolve>, resolve@patch:resolve@^1.17.0#builtin<compat/resolve>, resolve@patch:resolve@^1.18.1#builtin<compat/resolve>, resolve@patch:resolve@^1.19.0#builtin<compat/resolve>, resolve@patch:resolve@^1.4.0#builtin<compat/resolve>, resolve@patch:resolve@^1.9.0#builtin<compat/resolve>":
+"resolve@patch:resolve@^1.1.4#builtin<compat/resolve>, resolve@patch:resolve@^1.1.6#builtin<compat/resolve>, resolve@patch:resolve@^1.1.7#builtin<compat/resolve>, resolve@patch:resolve@^1.10.0#builtin<compat/resolve>, resolve@patch:resolve@^1.13.1#builtin<compat/resolve>, resolve@patch:resolve@^1.14.2#builtin<compat/resolve>, resolve@patch:resolve@^1.17.0#builtin<compat/resolve>, resolve@patch:resolve@^1.18.1#builtin<compat/resolve>, resolve@patch:resolve@^1.19.0#builtin<compat/resolve>, resolve@patch:resolve@^1.3.2#builtin<compat/resolve>, resolve@patch:resolve@^1.4.0#builtin<compat/resolve>, resolve@patch:resolve@^1.9.0#builtin<compat/resolve>":
   version: 1.20.0
   resolution: "resolve@patch:resolve@npm%3A1.20.0#builtin<compat/resolve>::version=1.20.0&hash=3388aa"
   dependencies:
@@ -13156,7 +13181,7 @@ fsevents@^1.2.7:
   languageName: node
   linkType: hard
 
-"semver@npm:2 || 3 || 4 || 5, semver@npm:^5.5.0, semver@npm:^5.6.0, semver@npm:^5.7.0":
+"semver@npm:2 || 3 || 4 || 5, semver@npm:^5.4.1, semver@npm:^5.5.0, semver@npm:^5.6.0, semver@npm:^5.7.0":
   version: 5.7.1
   resolution: "semver@npm:5.7.1"
   bin: