eslint-community · aladdin-add · Jun 17, 2021 · Jun 16, 2021 · aladdin-add · Jun 17, 2021
diff --git a/.eslintrc.js b/.eslintrc.js
@@ -7,7 +7,12 @@ module.exports = {
     'not-an-aardvark/node',
     'plugin:node/recommended',
     'plugin:self/all',
+    'plugin:unicorn/recommended',
   ],
+  parserOptions: {
+    ecmaVersion: 2021,
+    sourceType: 'script',
+  },
   rules: {
     'comma-dangle': [
       'error',
@@ -22,6 +27,14 @@ module.exports = {
     'self/meta-property-ordering': 'off',
     'self/require-meta-docs-url': 'off',
     'self/report-message-format': ['error', '^[^a-z].*.$'],
+
+    'unicorn/consistent-function-scoping': 'off',
+    'unicorn/no-array-callback-reference': 'off',
+    'unicorn/no-array-for-each': 'off',
+    'unicorn/no-array-reduce': 'off',
+    'unicorn/no-null': 'off',
+    'unicorn/prefer-module': 'off',
+    'unicorn/prevent-abbreviations': 'off',
   },
   overrides: [
     {

diff --git a/lib/rules/consistent-output.js b/lib/rules/consistent-output.js
@@ -39,7 +39,7 @@ module.exports = {
         utils.getTestInfo(context, ast).forEach(testRun => {
           const readableCases = testRun.invalid.filter(testCase => testCase.type === 'ObjectExpression');
           const casesWithoutOutput = readableCases
-            .filter(testCase => testCase.properties.map(utils.getKeyName).indexOf('output') === -1);
+            .filter(testCase => !testCase.properties.map(utils.getKeyName).includes('output'));
 
           if (
             (casesWithoutOutput.length < readableCases.length) ||

diff --git a/lib/rules/meta-property-ordering.js b/lib/rules/meta-property-ordering.js
@@ -51,7 +51,7 @@ module.exports = {
         const violatingProps = props.filter(prop => {
           const curr = orderMap.has(getKeyName(prop))
             ? orderMap.get(getKeyName(prop))
-            : Infinity;
+            : Number.POSITIVE_INFINITY;
           return last > (last = curr);
         });
 

diff --git a/lib/rules/no-deprecated-context-methods.js b/lib/rules/no-deprecated-context-methods.js
@@ -55,7 +55,7 @@ module.exports = {
 
     return {
       'Program:exit' () {
-        Array.from(utils.getContextIdentifiers(context, sourceCode.ast))
+        [...utils.getContextIdentifiers(context, sourceCode.ast)]
           .filter(
             contextId =>
               contextId.parent.type === 'MemberExpression' &&

diff --git a/lib/rules/no-identical-tests.js b/lib/rules/no-identical-tests.js
@@ -60,8 +60,8 @@ module.exports = {
         propertiesSetA.add(code);
       });
 
-      for (let i = 0; i < propertiesB.length; i++) {
-        const code = sourceCode.getText(propertiesB[i]);
+      for (const element of propertiesB) {
+        const code = sourceCode.getText(element);
         if (!propertiesSetA.has(code)) {
           return false;
         }

diff --git a/lib/rules/no-missing-placeholders.js b/lib/rules/no-missing-placeholders.js
@@ -56,7 +56,7 @@ module.exports = {
           ) {
             // Same regex as the one ESLint uses
             // https://github.com/eslint/eslint/blob/e5446449d93668ccbdb79d78cc69f165ce4fde07/lib/eslint.js#L990
-            const PLACEHOLDER_MATCHER = /\{\{\s*([^{}]+?)\s*\}\}/g;
+            const PLACEHOLDER_MATCHER = /{{\s*([^{}]+?)\s*}}/g;
             let match;
 
             while ((match = PLACEHOLDER_MATCHER.exec(reportInfo.message.value || messageStaticValue.value))) { // eslint-disable-line no-extra-parens

diff --git a/lib/rules/no-unused-placeholders.js b/lib/rules/no-unused-placeholders.js
@@ -57,7 +57,7 @@ module.exports = {
           ) {
             const message = reportInfo.message.value || messageStaticValue.value;
             // https://github.com/eslint/eslint/blob/2874d75ed8decf363006db25aac2d5f8991bd969/lib/linter.js#L986
-            const PLACEHOLDER_MATCHER = /\{\{\s*([^{}]+?)\s*\}\}/g;
+            const PLACEHOLDER_MATCHER = /{{\s*([^{}]+?)\s*}}/g;
             const placeholdersInMessage = new Set();
 
             message.replace(PLACEHOLDER_MATCHER, (fullMatch, term) => {

diff --git a/lib/rules/no-useless-token-range.js b/lib/rules/no-useless-token-range.js
@@ -103,7 +103,7 @@ module.exports = {
 
     return {
       'Program:exit' (ast) {
-        Array.from(utils.getSourceCodeIdentifiers(context, ast))
+        [...utils.getSourceCodeIdentifiers(context, ast)]
           .filter(identifier => identifier.parent.type === 'MemberExpression' &&
             identifier.parent.object === identifier &&
             identifier.parent.property.type === 'Identifier' &&

diff --git a/lib/rules/prefer-output-null.js b/lib/rules/prefer-output-null.js
@@ -43,7 +43,7 @@ module.exports = {
             function getTestInfo (key) {
               if (test.type === 'ObjectExpression') {
                 const res = test.properties.filter(item => item.key.name === key);
-                return res.length ? res[res.length - 1] : null;
+                return res.length > 0 ? res[res.length - 1] : null;
               }
               return key === 'code' ? test : null;
             }

diff --git a/lib/rules/prefer-placeholders.js b/lib/rules/prefer-placeholders.js
@@ -75,7 +75,7 @@ module.exports = {
           }
 
           if (
-            (messageNode.type === 'TemplateLiteral' && messageNode.expressions.length) ||
+            (messageNode.type === 'TemplateLiteral' && messageNode.expressions.length > 0) ||
             (messageNode.type === 'BinaryExpression' && messageNode.operator === '+')
           ) {
             context.report({

diff --git a/lib/rules/require-meta-docs-url.js b/lib/rules/require-meta-docs-url.js
@@ -94,6 +94,7 @@ module.exports = {
 
           message:
             !urlPropNode ? 'Rules should export a `meta.docs.url` property.' :
+              // eslint-disable-next-line unicorn/no-nested-ternary
               !expectedUrl ? '`meta.docs.url` property must be a string.' :
                 /* otherwise */ '`meta.docs.url` property must be `{{expectedUrl}}`.',
 

diff --git a/lib/rules/require-meta-fixable.js b/lib/rules/require-meta-fixable.js
@@ -65,6 +65,7 @@ module.exports = {
           const VALID_VALUES = new Set(['code', 'whitespace', null, undefined]);
           const valueIsValid = metaFixableProp.value.type === 'Literal'
             ? VALID_VALUES.has(metaFixableProp.value.value)
+            // eslint-disable-next-line unicorn/no-nested-ternary
             : metaFixableProp.value.type === 'TemplateLiteral' && metaFixableProp.value.quasis.length === 1
               ? VALID_VALUES.has(metaFixableProp.value.quasis[0].value.cooked)
               : metaFixableProp.value.type === 'Identifier' && metaFixableProp.value.name === 'undefined';

diff --git a/lib/rules/test-case-property-ordering.js b/lib/rules/test-case-property-ordering.js
@@ -58,10 +58,8 @@ module.exports = {
                 // current < lastChecked to catch unordered;
                 // and lastChecked === -1 to catch extra properties before.
                 if (current > -1 && (current < lastChecked || lastChecked === -1)) {
-                  let orderMsg = order.filter(item => keyNames.indexOf(item) > -1);
-                  orderMsg = orderMsg.concat(
-                    lastChecked === -1 ? keyNames.filter(item => order.indexOf(item) === -1) : []
-                  );
+                  let orderMsg = order.filter(item => keyNames.includes(item));
+                  orderMsg = [...orderMsg, ...lastChecked === -1 ? keyNames.filter(item => !order.includes(item)) : []];
 
                   context.report({
                     node: properties[i],

diff --git a/lib/utils.js b/lib/utils.js
@@ -53,7 +53,7 @@ function isNormalFunctionExpressionReference (node, scopeManager) {
   }
 
   const definitions = createReference.resolved.defs;
-  if (!definitions || !definitions.length) {
+  if (!definitions || definitions.length === 0) {
     return false;
   }
 
@@ -175,7 +175,7 @@ module.exports = {
   getContextIdentifiers (context, ast) {
     const ruleInfo = module.exports.getRuleInfo({ ast });
 
-    if (!ruleInfo || !ruleInfo.create.params.length || ruleInfo.create.params[0].type !== 'Identifier') {
+    if (!ruleInfo || ruleInfo.create.params.length === 0 || ruleInfo.create.params[0].type !== 'Identifier') {
       return new Set();
     }
 
@@ -270,7 +270,7 @@ module.exports = {
     // ['node', 'message', 'data', 'fix'].
     // Otherwise, the arguments are interpreted as ['node', 'loc', 'message', 'data', 'fix'].
 
-    if (!reportArgs.length) {
+    if (reportArgs.length === 0) {
       return null;
     }
 
@@ -320,7 +320,7 @@ module.exports = {
    * @returns {Set<ASTNode>} A set of all identifiers referring to the `SourceCode` object.
    */
   getSourceCodeIdentifiers (context, ast) {
-    return new Set(Array.from(module.exports.getContextIdentifiers(context, ast))
+    return new Set([...module.exports.getContextIdentifiers(context, ast)]
       .filter(identifier => identifier.parent &&
         identifier.parent.type === 'MemberExpression' &&
         identifier === identifier.parent.object &&
@@ -333,9 +333,9 @@ module.exports = {
         identifier.parent.parent.parent.id.type === 'Identifier'
       )
       .map(identifier => context.getDeclaredVariables(identifier.parent.parent.parent))
-      .reduce((allVariables, variablesForIdentifier) => allVariables.concat(variablesForIdentifier), [])
+      .reduce((allVariables, variablesForIdentifier) => [...allVariables, ...variablesForIdentifier], [])
       .map(variable => variable.references)
-      .reduce((allRefs, refsForVariable) => allRefs.concat(refsForVariable), [])
+      .reduce((allRefs, refsForVariable) => [...allRefs, ...refsForVariable], [])
       .map(ref => ref.identifier));
   },
 

diff --git a/package.json b/package.json
@@ -38,6 +38,7 @@
     "eslint-config-not-an-aardvark": "^2.1.0",
     "eslint-plugin-node": "^11.1.0",
     "eslint-plugin-self": "^1.2.1",
+    "eslint-plugin-unicorn": "^31.0.0",
     "eslint-scope": "^5.1.1",
     "espree": "^7.3.0",
     "estraverse": "^5.0.0",

diff --git a/tests/lib/index.js b/tests/lib/index.js
@@ -3,9 +3,11 @@
 const assert = require('chai').assert;
 const plugin = require('../..');
 
+const RULE_NAMES = Object.keys(plugin.rules);
+
 describe('exported plugin', () => {
   describe('adds a meta.docs.url property to each rule', () => {
-    Object.keys(plugin.rules).forEach(ruleName => {
+    RULE_NAMES.forEach(ruleName => {
       it(ruleName, () => {
         assert.match(
           plugin.rules[ruleName].meta.docs.url,

diff --git a/tests/lib/utils.js b/tests/lib/utils.js
@@ -1,6 +1,6 @@
 'use strict';
 
-const util = require('util');
+const { inspect } = require('util');
 const lodash = require('lodash');
 const espree = require('espree');
 const eslintScope = require('eslint-scope');
@@ -118,7 +118,7 @@ describe('utils', () => {
           const ruleInfo = utils.getRuleInfo({ ast });
           assert(
             lodash.isMatch(ruleInfo, CASES[ruleSource]),
-            `Expected \n${util.inspect(ruleInfo)}\nto match\n${util.inspect(CASES[ruleSource])}`
+            `Expected \n${inspect(ruleInfo)}\nto match\n${inspect(CASES[ruleSource])}`
           );
         });
       });
@@ -143,7 +143,7 @@ describe('utils', () => {
           const ruleInfo = utils.getRuleInfo({ ast, scopeManager });
           assert(
             lodash.isMatch(ruleInfo, expected),
-            `Expected \n${util.inspect(ruleInfo)}\nto match\n${util.inspect(expected)}`
+            `Expected \n${inspect(ruleInfo)}\nto match\n${inspect(expected)}`
           );
         });
       }
@@ -178,7 +178,7 @@ describe('utils', () => {
         const identifiers = utils.getContextIdentifiers(scope, ast);
 
         assert(identifiers instanceof Set, 'getContextIdentifiers should return a Set');
-        Array.from(identifiers).forEach((identifier, index) => {
+        [...identifiers].forEach((identifier, index) => {
           assert.strictEqual(identifier, CASES[ruleSource](ast)[index]);
         });
       });