fix: add default value for browserslist config path

packages/babel-helper-compilation-targets/src/index.js

@@ -179,6 +179,7 @@ export default function getTargets(
   options: GetTargetsOption = {},
 ): Targets {
   let { browsers, esmodules } = inputTargets;
+  const { configPath = "." } = options;
 
   validateBrowsers(browsers);
 
@@ -193,7 +194,7 @@ export default function getTargets(
   if (!browsers && shouldSearchForConfig) {
     browsers = browserslist.loadConfig({
       config: options.configFile,
-      path: options.configPath,
+      path: configPath,
       env: options.browserslistEnv,
     });
     if (browsers == null) {

packages/babel-helper-compilation-targets/test/load-browserslist-package-json/load-browserslist-package-json.spec.js

@@ -0,0 +1,19 @@
+import getTargets from "../..";
+import { fileURLToPath } from "url";
+import path from "path";
+
+const oldCwd = process.cwd();
+
+beforeAll(() => {
+  process.chdir(path.dirname(fileURLToPath(import.meta.url)));
+});
+
+afterAll(() => {
+  process.chdir(oldCwd);
+});
+
+it("loads packageJson.browserslist", () => {
+  const actual = getTargets({}, {});
+
+  expect(actual).toEqual({ chrome: "4.0.0" });
+});

packages/babel-helper-compilation-targets/test/load-browserslist-package-json/package.json

@@ -0,0 +1,3 @@
+{
+  "browserslist": "chrome 4"
+}

packages/babel-helper-compilation-targets/test/load-browserslistrc/.browserslistrc

@@ -0,0 +1,4 @@
+chrome 4
+
+[development]
+chrome 88

packages/babel-helper-compilation-targets/test/load-browserslistrc/load-browserslistrc.spec.js

@@ -0,0 +1,30 @@
+import getTargets from "../..";
+import { fileURLToPath } from "url";
+import path from "path";
+
+const oldCwd = process.cwd();
+
+beforeAll(() => {
+  process.chdir(path.dirname(fileURLToPath(import.meta.url)));
+});
+
+afterAll(() => {
+  process.chdir(oldCwd);
+});
+
+it("loads browserslistrc", () => {
+  const actual = getTargets({}, {});
+
+  expect(actual).toEqual({ chrome: "4.0.0" });
+});
+
+it("loads browserslistrc and respects browserslistEnv", () => {
+  const actual = getTargets(
+    {},
+    {
+      browserslistEnv: "development",
+    },
+  );
+
+  expect(actual).toEqual({ chrome: "88.0.0" });
+});