feature: @putout/plugin-eslint: remove-useless-match-to-flat: add

Author: coderaiser

packages/plugin-eslint/README.md

@@ -38,6 +38,7 @@ npm i @putout/plugin-eslint -D
 - ✅ [remove-overrides-with-empty-rules](#remove-overrides-with-empty-rules);
 - ✅ [remove-useless-slice](#remove-useless-slice);
 - ✅ [remove-useless-properties](#remove-useless-properties);
+- ✅ [remove-useless-match-to-flat](#remove-useless-match-to-flat);
 - ✅ [remove-parser-options](#remove-parser-options);
 - ✅ [remove-suffix-config](#remove-suffix-config);
 - ✅ [remove-create-eslint-config-with-one-argument](#remove-create-eslint-config-with-one-argument);
@@ -71,6 +72,7 @@ npm i @putout/plugin-eslint -D
         "eslint/remove-overrides-with-empty-rules": "on",
         "eslint/remove-useless-slice": "on",
         "eslint/remove-useless-properties": "on",
+        "eslint/remove-useless-match-to-flat": "on",
         "eslint/remove-parser-options": "on",
         "eslint/remove-suffix-config": "on",
         "eslint/remove-create-eslint-config-with-one-argument": "on",
@@ -635,6 +637,27 @@ module.exports = [
 module.exports = safeAlign;
 ```
 
+## remove-useless-match-to-flat
+
+Checkout in 🐊[**Putout Editor**](https://putout.cloudcmd.io/#/gist/bab49b08d12e779729265c05423bb856/a0b80b8e52f5319c40174773f36d8afbffb1c8b9).
+
+### ❌ Example of incorrect code
+
+```js
+import {safeAlign} from 'eslint-plugin-putout';
+
+export let match;
+export default createESLintConfig([safeAlign, matchToFlat(match)]);
+```
+
+## ✅ Example of correct code
+
+```js
+import {safeAlign} from 'eslint-plugin-putout';
+
+export default safeAlign;
+```
+
 ## convert-export-match-to-declaration
 
 Fixes [apply-match-to-flat](#apply-match-to-flat).

packages/plugin-eslint/lib/index.js

@@ -25,6 +25,7 @@ const removeParserOptions = require('./remove-parser-options');
 const removeSpreadFromCreateEslintConfig = require('./remove-spread-from-create-eslint-config');
 const removeSuffixConfig = require('./remove-suffix-config');
 const removeCreateEslintConfigWithOneArgument = require('./remove-create-eslint-config-with-one-argument');
+const removeUselessMatchToFlat = require('./remove-useless-match-to-flat');
 
 module.exports.rules = {
     'add-putout': addPutout,
@@ -52,4 +53,5 @@ module.exports.rules = {
     'remove-spread-from-create-eslint-config': removeSpreadFromCreateEslintConfig,
     'remove-suffix-config': removeSuffixConfig,
     'remove-create-eslint-config-with-one-argument': removeCreateEslintConfigWithOneArgument,
+    'remove-useless-match-to-flat': removeUselessMatchToFlat,
 };

packages/plugin-eslint/lib/remove-useless-match-to-flat/fixture/remove-useless-match-to-flat-fix.js

@@ -0,0 +1,3 @@
+import {safeAlign} from 'eslint-plugin-putout/config';
+
+export default createESLintConfig([safeAlign]);

packages/plugin-eslint/lib/remove-useless-match-to-flat/fixture/remove-useless-match-to-flat.js

@@ -0,0 +1,4 @@
+import {safeAlign} from 'eslint-plugin-putout/config';
+
+export let match;
+export default createESLintConfig([safeAlign, matchToFlat(match)]);

packages/plugin-eslint/lib/remove-useless-match-to-flat/index.js

@@ -0,0 +1,32 @@
+'use strict';
+
+const {operator} = require('putout');
+const {compare, remove} = operator;
+
+module.exports.report = () => `Avoid useless 'matchToFlat()'`;
+
+const EXPORT_LET_MATCH = 'export let match';
+
+module.exports.match = () => ({
+    'matchToFlat(match)': (vars, path) => getExportLetMatch(path),
+});
+
+module.exports.replace = () => ({
+    'matchToFlat(match)': (vars, path) => {
+        const letMatch = getExportLetMatch(path);
+        remove(letMatch);
+        
+        return '';
+    },
+});
+
+function getExportLetMatch(path) {
+    const programScope = path.scope.getProgramParent();
+    const programPath = programScope.path;
+    
+    for (const current of programPath.get('body'))
+        if (compare(current, EXPORT_LET_MATCH))
+            return current;
+    
+    return null;
+}

packages/plugin-eslint/lib/remove-useless-match-to-flat/index.spec.js

@@ -0,0 +1,20 @@
+'use strict';
+
+const {createTest} = require('@putout/test');
+const plugin = require('.');
+
+const test = createTest(__dirname, {
+    plugins: [
+        ['remove-useless-match-to-flat', plugin],
+    ],
+});
+
+test('eslint: remove-useless-match-to-flat: report', (t) => {
+    t.report('remove-useless-match-to-flat', `Avoid useless 'matchToFlat()'`);
+    t.end();
+});
+
+test('eslint: remove-useless-match-to-flat: transform', (t) => {
+    t.transform('remove-useless-match-to-flat');
+    t.end();
+});

packages/plugin-eslint/test/eslint.js

@@ -138,3 +138,8 @@ test('plugin-eslint: transform: remove-create-eslint-config-with-one-argument',
     t.transform('remove-create-eslint-config-with-one-argument');
     t.end();
 });
+
+test('plugin-eslint: transform: remove-useless-match-to-flat', (t) => {
+    t.transform('remove-useless-match-to-flat');
+    t.end();
+});

packages/plugin-eslint/test/fixture/remove-useless-match-to-flat-fix.js

@@ -0,0 +1,4 @@
+import {safeAlign} from 'eslint-plugin-putout';
+import {createESLintConfig} from '@putout/eslint-flat';
+
+export default safeAlign;

packages/plugin-eslint/test/fixture/remove-useless-match-to-flat.js

@@ -0,0 +1,4 @@
+import {safeAlign} from 'eslint-plugin-putout/config';
+
+export let match;
+export default createESLintConfig([safeAlign, matchToFlat(match)]);