From 73d97130afe79b8a458c215581ce86c62009ad8b Mon Sep 17 00:00:00 2001
From: Timo Zander <timo---zander@live.de>
Date: Sun, 1 Nov 2020 20:25:48 +0100
Subject: [PATCH] fix(eslint-plugin): [consistent-indexed-object-style] fix
 wrong autofix behaviour with generics (#2722)

---
 .../rules/consistent-indexed-object-style.ts  | 15 +++++++-
 .../consistent-indexed-object-style.test.ts   | 34 +++++++++++++++++++
 2 files changed, 48 insertions(+), 1 deletion(-)

diff --git a/packages/eslint-plugin/src/rules/consistent-indexed-object-style.ts b/packages/eslint-plugin/src/rules/consistent-indexed-object-style.ts
index 021f5038770..c1b86bf8c61 100644
--- a/packages/eslint-plugin/src/rules/consistent-indexed-object-style.ts
+++ b/packages/eslint-plugin/src/rules/consistent-indexed-object-style.ts
@@ -115,7 +115,20 @@ export default createRule<Options, MessageIds>({
       },
 
       TSInterfaceDeclaration(node): void {
-        checkMembers(node.body.body, node, `type ${node.id.name} = `, ';');
+        let genericTypes = '';
+
+        if ((node.typeParameters?.params ?? []).length > 0) {
+          genericTypes = `<${node.typeParameters?.params
+            .map(p => p.name.name)
+            .join(', ')}>`;
+        }
+
+        checkMembers(
+          node.body.body,
+          node,
+          `type ${node.id.name}${genericTypes} = `,
+          ';',
+        );
       },
     };
   },
diff --git a/packages/eslint-plugin/tests/rules/consistent-indexed-object-style.test.ts b/packages/eslint-plugin/tests/rules/consistent-indexed-object-style.test.ts
index 328f0cbf5dd..ebedccf424a 100644
--- a/packages/eslint-plugin/tests/rules/consistent-indexed-object-style.test.ts
+++ b/packages/eslint-plugin/tests/rules/consistent-indexed-object-style.test.ts
@@ -140,6 +140,32 @@ type Foo = Record<string, any>;
       errors: [{ messageId: 'preferRecord', line: 2, column: 1 }],
     },
 
+    // Interface with generic parameter
+    {
+      code: `
+interface Foo<A> {
+  [key: string]: A;
+}
+      `,
+      output: `
+type Foo<A> = Record<string, A>;
+      `,
+      errors: [{ messageId: 'preferRecord', line: 2, column: 1 }],
+    },
+
+    // Interface with multiple generic parameters
+    {
+      code: `
+interface Foo<A, B> {
+  [key: A]: B;
+}
+      `,
+      output: `
+type Foo<A, B> = Record<A, B>;
+      `,
+      errors: [{ messageId: 'preferRecord', line: 2, column: 1 }],
+    },
+
     // Type literal
     {
       code: 'type Foo = { [key: string]: any };',
@@ -175,6 +201,14 @@ type Foo = Record<string, any>;
       errors: [{ messageId: 'preferIndexSignature', line: 1, column: 12 }],
     },
 
+    // Type literal with generic parameter
+    {
+      code: 'type Foo<T> = Record<string, T>;',
+      options: ['index-signature'],
+      output: 'type Foo<T> = { [key: string]: T };',
+      errors: [{ messageId: 'preferIndexSignature', line: 1, column: 15 }],
+    },
+
     // Generic
     {
       code: 'type Foo = Generic<Record<string, any>>;',