[Refactor] use native JS instead of lodash

package.json

@@ -87,7 +87,6 @@
     "eslint-import-resolver-node": "^0.3.2",
     "eslint-module-utils": "^2.4.0",
     "has": "^1.0.3",
-    "lodash": "^4.17.11",
     "minimatch": "^3.0.4",
     "read-pkg-up": "^2.0.0",
     "resolve": "^1.11.0"

src/core/importType.js

@@ -1,13 +1,8 @@
-import cond from 'lodash/cond'
 import coreModules from 'resolve/lib/core'
 import { join } from 'path'
 
 import resolve from 'eslint-module-utils/resolve'
 
-function constant(value) {
-  return () => value
-}
-
 function baseModule(name) {
   if (isScoped(name)) {
     const [scope, pkg] = name.split('/')
@@ -76,17 +71,17 @@ function isRelativeToSibling(name) {
   return /^\.[\\/]/.test(name)
 }
 
-const typeTest = cond([
-  [isAbsolute, constant('absolute')],
-  [isBuiltIn, constant('builtin')],
-  [isInternalModule, constant('internal')],
-  [isExternalModule, constant('external')],
-  [isScoped, constant('external')],
-  [isRelativeToParent, constant('parent')],
-  [isIndex, constant('index')],
-  [isRelativeToSibling, constant('sibling')],
-  [constant(true), constant('unknown')],
-])
+function typeTest(name, settings, path) {
+  if (isAbsolute(name, settings, path)) { return 'absolute' }
+  if (isBuiltIn(name, settings, path)) { return 'builtin' }
+  if (isInternalModule(name, settings, path)) { return 'internal' }
+  if (isExternalModule(name, settings, path)) { return 'external' }
+  if (isScoped(name, settings, path)) { return 'external' }
+  if (isRelativeToParent(name, settings, path)) { return 'parent' }
+  if (isIndex(name, settings, path)) { return 'index' }
+  if (isRelativeToSibling(name, settings, path)) { return 'sibling' }
+  return 'unknown'
+}
 
 export default function resolveImportType(name, context) {
   return typeTest(name, context.settings, resolve(name, context))

src/rules/no-extraneous-dependencies.js

@@ -1,6 +1,5 @@
 import path from 'path'
 import fs from 'fs'
-import { isArray, isEmpty } from 'lodash'
 import readPkgUp from 'read-pkg-up'
 import minimatch from 'minimatch'
 import resolve from 'eslint-module-utils/resolve'
@@ -31,15 +30,15 @@ function getDependencies(context, packageDir) {
       peerDependencies: {},
     }
 
-    if (!isEmpty(packageDir)) {
-      if (!isArray(packageDir)) {
+    if (packageDir && packageDir.length > 0) {
+      if (!Array.isArray(packageDir)) {
         paths = [path.resolve(packageDir)]
       } else {
         paths = packageDir.map(dir => path.resolve(dir))
       }
     }
 
-    if (!isEmpty(paths)) {
+    if (paths.length > 0) {
       // use rule config to find package.json
       paths.forEach(dir => {
         const _packageContent = extractDepFields(
@@ -70,7 +69,7 @@ function getDependencies(context, packageDir) {
 
     return packageContent
   } catch (e) {
-    if (!isEmpty(paths) && e.code === 'ENOENT') {
+    if (paths.length > 0 && e.code === 'ENOENT') {
       context.report({
         message: 'The package.json file could not be found.',
         loc: { line: 0, column: 0 },

tests/dep-time-travel.sh

@@ -7,7 +7,7 @@ npm install --no-save eslint@$ESLINT_VERSION --ignore-scripts || true
 # completely remove the new typescript parser for ESLint < v5
 if [[ "$ESLINT_VERSION" -lt "5" ]]; then
   echo "Removing @typescript-eslint/parser..."
-  npm uninstall @typescript-eslint/parser
+  npm uninstall --no-save @typescript-eslint/parser
 fi
 
 # use these alternate typescript dependencies for ESLint < v4

tests/src/rules/no-amd.js

@@ -1,4 +1,6 @@
 import { RuleTester } from 'eslint'
+import eslintPkg from 'eslint/package.json'
+import semver from 'semver'
 
 var ruleTester = new RuleTester()
 
@@ -25,11 +27,11 @@ ruleTester.run('no-amd', require('rules/no-amd'), {
     'define("a")',
 	],
 
-	invalid: [
-    { code: 'define([], function() {})', errors: [ { message: 'Expected imports instead of AMD define().' }] },
-    { code: 'define(["a"], function(a) { console.log(a); })', errors: [ { message: 'Expected imports instead of AMD define().' }] },
+	invalid: semver.satisfies(eslintPkg.version, '< 4.0.0') ? [] : [
+      { code: 'define([], function() {})', errors: [ { message: 'Expected imports instead of AMD define().' }] },
+      { code: 'define(["a"], function(a) { console.log(a); })', errors: [ { message: 'Expected imports instead of AMD define().' }] },
 
-		{ code: 'require([], function() {})', errors: [ { message: 'Expected imports instead of AMD require().' }] },
-		{ code: 'require(["a"], function(a) { console.log(a); })', errors: [ { message: 'Expected imports instead of AMD require().' }] },
+      { code: 'require([], function() {})', errors: [ { message: 'Expected imports instead of AMD require().' }] },
+      { code: 'require(["a"], function(a) { console.log(a); })', errors: [ { message: 'Expected imports instead of AMD require().' }] },
 	],
 })

tests/src/rules/no-commonjs.js

@@ -1,4 +1,6 @@
 import { RuleTester } from 'eslint'
+import eslintPkg from 'eslint/package.json'
+import semver from 'semver'
 
 const EXPORT_MESSAGE = 'Expected "export" or "export default"'
     , IMPORT_MESSAGE = 'Expected "import" instead of "require()"'
@@ -59,9 +61,11 @@ ruleTester.run('no-commonjs', require('rules/no-commonjs'), {
   invalid: [
 
     // imports
-    { code: 'var x = require("x")', errors: [ { message: IMPORT_MESSAGE }] },
-    { code: 'x = require("x")', errors: [ { message: IMPORT_MESSAGE }] },
-    { code: 'require("x")', errors: [ { message: IMPORT_MESSAGE }] },
+    ...(semver.satisfies(eslintPkg.version, '< 4.0.0') ? [] : [
+      { code: 'var x = require("x")', errors: [ { message: IMPORT_MESSAGE }] },
+      { code: 'x = require("x")', errors: [ { message: IMPORT_MESSAGE }] },
+      { code: 'require("x")', errors: [ { message: IMPORT_MESSAGE }] },
+    ]),
 
     // exports
     { code: 'exports.face = "palm"', errors: [ { message: EXPORT_MESSAGE }] },