Add ignores option to no-unused-keys rule

docs/rules/no-unused-keys.md

@@ -159,6 +159,7 @@ i18n.t('hi')
     {
       "src": "./src",
       "extensions": [".js", ".vue"],
+      "ignores": [],
       "enableFix": false
     }
   ]
@@ -167,6 +168,7 @@ i18n.t('hi')
 
 - `src`: specify the source codes directory to be able to lint. If you don't set any options, it set to `process.cwd()` as default.
 - `extensions`: an array to allow specified lintable target file extension. If you don't set any options, it set to `.js` and `.vue` as default.
+- `ignores`: An array of key names and patterns to exclude from the check. If you want to specify a pattern, specify a string such as `/pattern/`.
 - `enableFix`: if `true`, enable automatically remove unused keys on `eslint --fix`. If you don't set any options, it set to `false` as default. (This is an experimental feature.)
 
 ## :couple: Related Rules

lib/rules/no-raw-text.ts

@@ -25,6 +25,7 @@ import type {
 } from '../types'
 import { isKebabCase, pascalCase } from '../utils/casing'
 import { createRule } from '../utils/rule'
+import { toRegExp } from '../utils/regexp'
 
 type LiteralValue = VAST.ESLintLiteral['value']
 type StaticTemplateLiteral = VAST.ESLintTemplateLiteral & {
@@ -54,32 +55,9 @@ function getFixQuote(quotes: Quotes, code: string) {
   }
   return null
 }
-const RE_REGEXP_CHAR = /[\\^$.*+?()[\]{}|]/gu
-const RE_HAS_REGEXP_CHAR = new RegExp(RE_REGEXP_CHAR.source)
-const RE_REGEXP_STR = /^\/(.+)\/(.*)$/u
-function toRegExp(str: string): RegExp {
-  const parts = RE_REGEXP_STR.exec(str)
-  if (parts) {
-    return new RegExp(parts[1], parts[2])
-  }
-  return new RegExp(`^${escape(str)}$`)
-}
 const hasOnlyWhitespace = (value: string) => /^[\r\n\s\t\f\v]+$/.test(value)
 const INNER_START_OFFSET = '<template>'.length
 
-/**
- * Escapes the `RegExp` special characters "^", "$", "\", ".", "*", "+",
- * "?", "(", ")", "[", "]", "{", "}", and "|" in `string`.
- *
- * @param {string} string The string to escape.
- * @returns {string} Returns the escaped string.
- */
-function escape(str: string) {
-  return str && RE_HAS_REGEXP_CHAR.test(str)
-    ? str.replace(RE_REGEXP_CHAR, '\\$&')
-    : str
-}
-
 /**
  * Get the attribute to be verified from the element name.
  */

lib/rules/no-unused-keys.ts

@@ -23,6 +23,7 @@ import type {
 import { joinPath, parsePath } from '../utils/key-path'
 import { getCwd } from '../utils/get-cwd'
 import { createRule } from '../utils/rule'
+import { toRegExp } from '../utils/regexp'
 const debug = debugBuilder('eslint-plugin-vue-i18n:no-unused-keys')
 
 type UsedKeys = {
@@ -78,6 +79,7 @@ function create(context: RuleContext): RuleListener {
   const filename = context.getFilename()
   const options = (context.options && context.options[0]) || {}
   const enableFix = options.enableFix
+  const ignores = ((options.ignores || []) as string[]).map(toRegExp)
 
   function createVerifyContext<N extends JSONAST.JSONNode | YAMLAST.YAMLNode>(
     usedKeys: UsedKeys,
@@ -129,6 +131,9 @@ function create(context: RuleContext): RuleListener {
       reports() {
         for (const { node, keyPath } of reports) {
           const keyPathStr = joinPath(...keyPath)
+          if (ignores.some(reg => reg.test(keyPathStr))) {
+            continue
+          }
           const fix = buildFixer(node)
           context.report({
             message: `unused '${keyPathStr}' key`,
@@ -578,6 +583,10 @@ export = createRule({
             items: { type: 'string' },
             default: ['.js', '.vue']
           },
+          ignores: {
+            type: 'array',
+            items: { type: 'string' }
+          },
           enableFix: {
             type: 'boolean'
           }

lib/utils/regexp.ts

@@ -0,0 +1,20 @@
+const RE_REGEXP_CHAR = /[\\^$.*+?()[\]{}|]/gu
+const RE_REGEXP_STR = /^\/(.+)\/(.*)$/u
+
+export function toRegExp(str: string): RegExp {
+  const parts = RE_REGEXP_STR.exec(str)
+  if (parts) {
+    return new RegExp(parts[1], parts[2])
+  }
+  return new RegExp(`^${escape(str)}$`)
+}
+/**
+ * Escapes the `RegExp` special characters "^", "$", "\", ".", "*", "+",
+ * "?", "(", ")", "[", "]", "{", "}", and "|" in `string`.
+ *
+ * @param {string} string The string to escape.
+ * @returns {string} Returns the escaped string.
+ */
+function escape(str: string) {
+  return str && str.replace(RE_REGEXP_CHAR, '\\$&')
+}

tests/lib/rules/no-unused-keys.ts

@@ -205,6 +205,52 @@ new RuleTester({
         }
       }
       </script>`
+    },
+    {
+      filename: 'test.vue',
+      code: `
+    <i18n locale="en">
+    {
+      "foo": "foo",
+      "bar": {
+        "nest": "nest",
+        "ignore": "ignore",
+      },
+      "ignore": "ignore",
+    }
+    </i18n>
+    <script>
+    export default {
+      created () {
+        this.$t('foo')
+        this.$t('bar.nest')
+      }
+    }
+    </script>`,
+      options: [{ ignores: ['ignore', 'bar.ignore'] }]
+    },
+    {
+      filename: 'test.vue',
+      code: `
+    <i18n locale="en">
+    {
+      "foo": "foo",
+      "bar": {
+        "nest": "nest",
+        "ptn_foo": "ignore",
+      },
+      "ptn_bar": "ignore"
+    }
+    </i18n>
+    <script>
+    export default {
+      created () {
+        this.$t('foo')
+        this.$t('bar.nest')
+      }
+    }
+    </script>`,
+      options: [{ ignores: ['/ptn/'] }]
     }
   ],
   invalid: [
@@ -1026,6 +1072,80 @@ ${' '.repeat(6)}
     <script></script>`,
       errors: [`unused '["[{foo: bar}]"].foo' key`]
     },
+    {
+      filename: 'test.vue',
+      code: `
+    <i18n locale="en">
+    {
+      "foo": "foo",
+      "bar": {
+        "nest": "nest",
+        "ignore": "ignore",
+        "not_ignore": "not_ignore",
+      },
+      "ignore": "ignore",
+      "not_ignore": "not_ignore",
+    }
+    </i18n>
+    <script>
+    export default {
+      created () {
+        this.$t('foo')
+        this.$t('bar.nest')
+      }
+    }
+    </script>`,
+      options: [{ ignores: ['ignore', 'bar.ignore'] }],
+      errors: [
+        {
+          message: "unused 'bar.not_ignore' key",
+          line: 8,
+          column: 9
+        },
+        {
+          message: "unused 'not_ignore' key",
+          line: 11,
+          column: 7
+        }
+      ]
+    },
+    {
+      filename: 'test.vue',
+      code: `
+    <i18n locale="en">
+    {
+      "foo": "foo",
+      "bar": {
+        "nest": "nest",
+        "ptn_foo": "ignore",
+        "no_hit_pattern_foo": "not_ignore"
+      },
+      "ptn_bar": "ignore",
+      "no_hit_pattern_bar": "not_ignore"
+    }
+    </i18n>
+    <script>
+    export default {
+      created () {
+        this.$t('foo')
+        this.$t('bar.nest')
+      }
+    }
+    </script>`,
+      options: [{ ignores: ['/ptn/'] }],
+      errors: [
+        {
+          message: "unused 'bar.no_hit_pattern_foo' key",
+          line: 8,
+          column: 9
+        },
+        {
+          message: "unused 'no_hit_pattern_bar' key",
+          line: 11,
+          column: 7
+        }
+      ]
+    },
     ...getTestCasesFromFixtures(
       {
         cwd: join(cwdRoot, './valid')