From 5bbfc11e1167ad52d1015b1e07a0e01191e61162 Mon Sep 17 00:00:00 2001
From: yeonjuan <yeonjuan93@naver.com>
Date: Mon, 22 Jan 2024 00:46:29 +0900
Subject: [PATCH] fix(eslint-plugin): [no-useless-template-literals] incorrect
 bigint autofix result

---
 .../src/rules/no-useless-template-literals.ts | 13 +++-------
 .../no-useless-template-literals.test.ts      | 25 ++++++++++++++++++-
 2 files changed, 28 insertions(+), 10 deletions(-)

diff --git a/packages/eslint-plugin/src/rules/no-useless-template-literals.ts b/packages/eslint-plugin/src/rules/no-useless-template-literals.ts
index d5a8a602b6b4..394947ff9a32 100644
--- a/packages/eslint-plugin/src/rules/no-useless-template-literals.ts
+++ b/packages/eslint-plugin/src/rules/no-useless-template-literals.ts
@@ -6,6 +6,7 @@ import {
   createRule,
   getConstrainedTypeAtLocation,
   getParserServices,
+  getStaticStringValue,
   isTypeFlagSet,
   isUndefinedIdentifier,
 } from '../util';
@@ -118,16 +119,10 @@ export default createRule<[], MessageId>({
                 ]),
               ];
 
-              // Remove quotes for string literals (i.e. `'a'` will become `a`).
-              const isStringLiteral =
-                isUnderlyingTypeString(expression) &&
-                expression.type === AST_NODE_TYPES.Literal;
+              const stringValue = getStaticStringValue(expression);
 
-              if (isStringLiteral) {
-                const escapedValue = expression.value.replace(
-                  /([`$\\])/g,
-                  '\\$1',
-                );
+              if (stringValue != null) {
+                const escapedValue = stringValue.replace(/([`$\\])/g, '\\$1');
 
                 fixes.push(fixer.replaceText(expression, escapedValue));
               }
diff --git a/packages/eslint-plugin/tests/rules/no-useless-template-literals.test.ts b/packages/eslint-plugin/tests/rules/no-useless-template-literals.test.ts
index 674b4ccefe77..0bbd79c15654 100644
--- a/packages/eslint-plugin/tests/rules/no-useless-template-literals.test.ts
+++ b/packages/eslint-plugin/tests/rules/no-useless-template-literals.test.ts
@@ -17,7 +17,6 @@ ruleTester.run('no-useless-template-literals', rule, {
   valid: [
     "const string = 'a';",
     'const string = `a`;',
-
     `
       declare const string: 'a';
       \`\${string}b\`;
@@ -147,6 +146,30 @@ ruleTester.run('no-useless-template-literals', rule, {
         },
       ],
     },
+    {
+      code: '`${1n}`;',
+      output: '`1`;',
+      errors: [
+        {
+          messageId: 'noUselessTemplateLiteral',
+          line: 1,
+          column: 4,
+          endColumn: 6,
+        },
+      ],
+    },
+    {
+      code: '`${/a/}`;',
+      output: '`/a/`;',
+      errors: [
+        {
+          messageId: 'noUselessTemplateLiteral',
+          line: 1,
+          column: 4,
+          endColumn: 7,
+        },
+      ],
+    },
 
     {
       code: noFormat`\`\${    1    }\`;`,