From b847e4e862ed7882b8863e78534ccc0364fd682e Mon Sep 17 00:00:00 2001
From: yosuke ota <otameshiyo23@gmail.com>
Date: Sat, 30 Oct 2021 17:11:46 +0900
Subject: [PATCH] Add `SCREAMING_SNAKE_CASE` option to `key-format-style` rule

---
 lib/rules/key-format-style.ts       |  7 ++++-
 lib/utils/casing.ts                 | 25 +++++++++++++++--
 tests/lib/rules/key-format-style.ts | 43 +++++++++++++++++++++++++++++
 3 files changed, 72 insertions(+), 3 deletions(-)

diff --git a/lib/rules/key-format-style.ts b/lib/rules/key-format-style.ts
index 01d8fc79..1d6ebf18 100644
--- a/lib/rules/key-format-style.ts
+++ b/lib/rules/key-format-style.ts
@@ -11,7 +11,12 @@ import { getCasingChecker } from '../utils/casing'
 import type { LocaleMessage } from '../utils/locale-messages'
 const debug = debugBuilder('eslint-plugin-vue-i18n:key-format-style')
 
-const allowedCaseOptions = ['camelCase', 'kebab-case', 'snake_case'] as const
+const allowedCaseOptions = [
+  'camelCase',
+  'kebab-case',
+  'snake_case',
+  'SCREAMING_SNAKE_CASE'
+] as const
 type CaseOption = typeof allowedCaseOptions[number]
 
 function create(context: RuleContext): RuleListener {
diff --git a/lib/utils/casing.ts b/lib/utils/casing.ts
index 74077329..5686f638 100644
--- a/lib/utils/casing.ts
+++ b/lib/utils/casing.ts
@@ -16,6 +16,14 @@ function hasUpper(str: string) {
   return /[A-Z]/u.exec(str)
 }
 
+/**
+ * Checks whether the given string has lower.
+ * @param {string} str
+ */
+function hasLower(str: string) {
+  return /[a-z]/u.test(str)
+}
+
 /**
  * Checks whether the given string is kebab-case.
  */
@@ -74,18 +82,31 @@ export function isPascalCase(str: string): boolean {
   return true
 }
 
+/**
+ * Checks whether the given string is SCREAMING_SNAKE_CASE.
+ * @param {string} str
+ */
+export function isScreamingSnakeCase(str: string): boolean {
+  if (hasLower(str) || hasSymbols(str) || /-|__|\s/u.test(str)) {
+    return false
+  }
+  return true
+}
+
 const checkersMap = {
   'kebab-case': isKebabCase,
   snake_case: isSnakeCase,
   camelCase: isCamelCase,
-  PascalCase: isPascalCase
+  PascalCase: isPascalCase,
+  SCREAMING_SNAKE_CASE: isScreamingSnakeCase
 }
 
 export const allowedCaseOptions = [
   'camelCase',
   'kebab-case',
   'PascalCase',
-  'snake_case'
+  'snake_case',
+  'SCREAMING_SNAKE_CASE'
 ] as const
 
 /**
diff --git a/tests/lib/rules/key-format-style.ts b/tests/lib/rules/key-format-style.ts
index 8e0695dc..5d3439f0 100644
--- a/tests/lib/rules/key-format-style.ts
+++ b/tests/lib/rules/key-format-style.ts
@@ -489,6 +489,49 @@ tester.run('key-format-style', rule as never, {
           line: 5
         }
       ]
+    },
+    {
+      filename: 'test.vue',
+      code: `
+      <i18n>
+      {
+        "en-US": {
+          "foo-bar": "baz",
+          "fooBar": "baz",
+          "foo_bar": "baz",
+          "FOO_BAR": "baz",
+        }
+      }
+      </i18n>
+      <template></template>
+      <script></script>`,
+      errors: [
+        '"foo-bar" is not camelCase',
+        '"foo_bar" is not camelCase',
+        '"FOO_BAR" is not camelCase'
+      ]
+    },
+    {
+      filename: 'test.vue',
+      code: `
+      <i18n>
+      {
+        "en-US": {
+          "foo-bar": "baz",
+          "fooBar": "baz",
+          "foo_bar": "baz",
+          "FOO_BAR": "baz",
+        }
+      }
+      </i18n>
+      <template></template>
+      <script></script>`,
+      options: ['SCREAMING_SNAKE_CASE'],
+      errors: [
+        '"foo-bar" is not SCREAMING_SNAKE_CASE',
+        '"fooBar" is not SCREAMING_SNAKE_CASE',
+        '"foo_bar" is not SCREAMING_SNAKE_CASE'
+      ]
     }
   ]
 })