Simplify Jest config

Author: mjackson

jest-preset.js

@@ -1,36 +1,27 @@
-const { jest: lernaAliases } = require("lerna-alias");
-const { TEST_ENV } = process.env;
-
-const moduleType = ["cjs", "umd"].includes(TEST_ENV) ? TEST_ENV : "modules";
-
-const mapValues = (obj, mapper) => {
-  const mapped = {};
-  Object.keys(obj).forEach(key => {
-    mapped[key] = mapper(obj[key]);
-  });
-  return mapped;
-};
-
-const mapAliasPathToSourceEntry = path =>
-  path.replace("/src/index", `/${moduleType}/index`);
-
-const mapAliasPathToDistEntry = path =>
-  path.replace(/\/([a-z-]+)\/src\/index/, (match, pkgName) =>
-    match.replace("/src/index", `/${moduleType}/${pkgName}`)
-  );
+function resolveName(packageName) {
+  switch (process.env.TEST_ENV) {
+    case "cjs":
+      return `<rootDir>/../${packageName}/cjs/${packageName}.js`;
+    case "umd":
+      return `<rootDir>/../${packageName}/umd/${packageName}.js`;
+    case "module":
+    default:
+      return `<rootDir>/../${packageName}/modules/index.js`;
+  }
+}
 
 module.exports = {
   testRunner: "jest-circus/runner",
   restoreMocks: true,
   globals: {
     __DEV__: true
   },
-  moduleNameMapper: mapValues(
-    lernaAliases(),
-    moduleType === "modules"
-      ? mapAliasPathToSourceEntry
-      : mapAliasPathToDistEntry
-  ),
+  moduleNameMapper: {
+    "^react-router$": resolveName("react-router"),
+    "^react-router-config$": resolveName("react-router-config"),
+    "^react-router-dom$": resolveName("react-router-dom"),
+    "^react-router-native$": resolveName("react-router-native")
+  },
   setupFiles: ["raf/polyfill"],
   testMatch: ["**/__tests__/**/*-test.js"],
   transform: {

package.json

@@ -24,7 +24,6 @@
     "jest": "^24.9.0",
     "jest-circus": "^24.9.0",
     "lerna": "^3.13.4",
-    "lerna-alias": "3.0.3-0",
     "lerna-changelog": "^0.8.2",
     "metro-react-native-babel-preset": "^0.56.0",
     "prettier": "^1.14.3",

packages/react-router-native/jest.config.js

@@ -1,37 +1,36 @@
 const preset = require("react-native/jest-preset");
-const { jest: lernaAliases } = require("lerna-alias");
 
-const mapValues = (obj, mapper) => {
+function mapValues(obj, mapper) {
   const mapped = {};
+
   Object.keys(obj).forEach(key => {
     mapped[key] = mapper(obj[key]);
   });
-  return mapped;
-};
 
-const omitBy = (obj, predicate) => {
-  const mapped = {};
-  Object.keys(obj).forEach(key => {
-    if (predicate(obj[key], key)) {
-      return;
-    }
-    mapped[key] = obj[key];
-  });
   return mapped;
-};
+}
 
-const monorepoAliases = lernaAliases();
-const transpilableAliases = omitBy(monorepoAliases, (_, key) =>
-  key.includes("react-router-native")
-);
+function resolveName(packageName) {
+  switch (process.env.TEST_ENV) {
+    case "cjs":
+      return `<rootDir>/../${packageName}/cjs/${packageName}.js`;
+    case "umd":
+      return `<rootDir>/../${packageName}/umd/${packageName}.js`;
+    case "module":
+    default:
+      return `<rootDir>/../${packageName}/modules/index.js`;
+  }
+}
 
 module.exports = {
   ...preset,
   testRunner: "jest-circus/runner",
   restoreMocks: true,
-  moduleNameMapper: mapValues(transpilableAliases, path =>
-    path.replace("/src/index", `/modules/index`)
-  ),
+  moduleNameMapper: {
+    "^react-router$": resolveName("react-router"),
+    "^react-router-dom$": resolveName("react-router-dom"),
+    "^react-router-config": resolveName("react-router-config")
+  },
   transform: mapValues(preset.transform, transformer =>
     transformer === "babel-jest"
       ? ["babel-jest", { rootMode: "upward" }]

yarn.lock

@@ -4316,13 +4316,6 @@ get-caller-file@^2.0.1:
   resolved "https://registry.yarnpkg.com/get-caller-file/-/get-caller-file-2.0.5.tgz#4f94412a82db32f36e3b0b9741f8a97feb031f7e"
   integrity sha512-DyFP3BM/3YHTQOCUL/w0OZHR0lpKeGrxotcHWcqNEdnltqFwXVfhEBQ94eIo34AfQpo0rGki4cyIiftY06h2Fg==
 
-get-lerna-packages@^0.1.1:
-  version "0.1.1"
-  resolved "https://registry.npmjs.org/get-lerna-packages/-/get-lerna-packages-0.1.1.tgz#37aaaac36fd14f00082f17b1096dd6c69290cef9"
-  integrity sha512-venxkvga57gOUZoTmXZlJ0zHc8cmvsx7Y0GTMcoEK/7OCEK3PLpG5gVTbUUMJaLxbzK13AWQdKPf1LSkuEfWqA==
-  dependencies:
-    glob "^7.1.2"
-
 get-pkg-repo@^1.0.0:
   version "1.4.0"
   resolved "https://registry.yarnpkg.com/get-pkg-repo/-/get-pkg-repo-1.4.0.tgz#c73b489c06d80cc5536c2c853f9e05232056972d"
@@ -5759,13 +5752,6 @@ left-pad@^1.3.0:
   resolved "https://registry.yarnpkg.com/left-pad/-/left-pad-1.3.0.tgz#5b8a3a7765dfe001261dde915589e782f8c94d1e"
   integrity sha512-XI5MPzVNApjAyhQzphX8BkmKsKUxD4LdyK24iZeQGinBN9yTQT3bFlCBy/aVx2HrNcqQGsdot8ghrjyrvMCoEA==
 
-[email protected]:
-  version "3.0.3-0"
-  resolved "https://registry.npmjs.org/lerna-alias/-/lerna-alias-3.0.3-0.tgz#d681842deed66644ab9f38a7b365658cfe52dd43"
-  integrity sha512-IX0c2QH3v4rkgE+iG7Ro0FSEWKqqrMhvbGbB1txrnaJ8YbcrNbJ0IPpcJi+uiiPLV3olNX74EO08x9hGZ+J5ig==
-  dependencies:
-    get-lerna-packages "^0.1.1"
-
 lerna-changelog@^0.8.2:
   version "0.8.2"
   resolved "https://registry.yarnpkg.com/lerna-changelog/-/lerna-changelog-0.8.2.tgz#05dc24add91741a4c198a79f82a1a4ac3fbb4754"