From 6bb20ed973241b125549fcaee8b375c3c1c6c50d Mon Sep 17 00:00:00 2001
From: YeonJuan <yeonjuan93@naver.com>
Date: Wed, 8 Jan 2025 00:14:41 +0900
Subject: [PATCH 1/2] fix(eslint-plugin): [no-unnecessary-type-arguments]
 handle type args on jsx

---
 .../rules/no-unnecessary-type-arguments.ts    |  9 +++-
 .../no-unnecessary-type-arguments.test.ts     | 42 +++++++++++++++++++
 2 files changed, 49 insertions(+), 2 deletions(-)

diff --git a/packages/eslint-plugin/src/rules/no-unnecessary-type-arguments.ts b/packages/eslint-plugin/src/rules/no-unnecessary-type-arguments.ts
index 95f0e66ccecc..caad90d40b41 100644
--- a/packages/eslint-plugin/src/rules/no-unnecessary-type-arguments.ts
+++ b/packages/eslint-plugin/src/rules/no-unnecessary-type-arguments.ts
@@ -142,7 +142,8 @@ function getTypeParametersFromNode(
   if (
     ts.isCallExpression(tsNode) ||
     ts.isNewExpression(tsNode) ||
-    ts.isTaggedTemplateExpression(tsNode)
+    ts.isTaggedTemplateExpression(tsNode) ||
+    ts.isJsxOpeningElement(tsNode)
   ) {
     return getTypeParametersFromCall(node, tsNode, checker);
   }
@@ -189,7 +190,11 @@ function getTypeParametersFromType(
 
 function getTypeParametersFromCall(
   node: TSESTree.TSTypeParameterInstantiation,
-  tsNode: ts.CallExpression | ts.NewExpression | ts.TaggedTemplateExpression,
+  tsNode:
+    | ts.CallExpression
+    | ts.JsxOpeningElement
+    | ts.NewExpression
+    | ts.TaggedTemplateExpression,
   checker: ts.TypeChecker,
 ): readonly ts.TypeParameterDeclaration[] | undefined {
   const sig = checker.getResolvedSignature(tsNode);
diff --git a/packages/eslint-plugin/tests/rules/no-unnecessary-type-arguments.test.ts b/packages/eslint-plugin/tests/rules/no-unnecessary-type-arguments.test.ts
index ad4133e13ff4..b5aaf6ca6437 100644
--- a/packages/eslint-plugin/tests/rules/no-unnecessary-type-arguments.test.ts
+++ b/packages/eslint-plugin/tests/rules/no-unnecessary-type-arguments.test.ts
@@ -179,6 +179,21 @@ namespace Foo {
 }
 class Bar extends Foo<string> {}
     `,
+    {
+      code: `
+function Button<T>() {
+  return <div></div>;
+}
+const button = <Button<string>></Button>;
+      `,
+      languageOptions: {
+        parserOptions: {
+          ecmaFeatures: {
+            jsx: true,
+          },
+        },
+      },
+    },
   ],
   invalid: [
     {
@@ -560,5 +575,32 @@ namespace Foo {
 class Bar extends Foo {}
       `,
     },
+    {
+      code: `
+function Button<T = string>() {
+  return <div></div>;
+}
+const button = <Button<string>></Button>;
+      `,
+      errors: [
+        {
+          line: 5,
+          messageId: 'unnecessaryTypeParameter',
+        },
+      ],
+      languageOptions: {
+        parserOptions: {
+          ecmaFeatures: {
+            jsx: true,
+          },
+        },
+      },
+      output: `
+function Button<T = string>() {
+  return <div></div>;
+}
+const button = <Button></Button>;
+      `,
+    },
   ],
 });

From 672f5335156cfa4b3975a99cdad7b06201a2d936 Mon Sep 17 00:00:00 2001
From: YeonJuan <yeonjuan93@naver.com>
Date: Fri, 10 Jan 2025 20:28:14 +0900
Subject: [PATCH 2/2] apply review

---
 .../rules/no-unnecessary-type-arguments.ts    |  4 +-
 .../no-unnecessary-type-arguments.test.ts     | 42 +++++++++++++++++++
 2 files changed, 45 insertions(+), 1 deletion(-)

diff --git a/packages/eslint-plugin/src/rules/no-unnecessary-type-arguments.ts b/packages/eslint-plugin/src/rules/no-unnecessary-type-arguments.ts
index caad90d40b41..c380c3cb24f3 100644
--- a/packages/eslint-plugin/src/rules/no-unnecessary-type-arguments.ts
+++ b/packages/eslint-plugin/src/rules/no-unnecessary-type-arguments.ts
@@ -143,7 +143,8 @@ function getTypeParametersFromNode(
     ts.isCallExpression(tsNode) ||
     ts.isNewExpression(tsNode) ||
     ts.isTaggedTemplateExpression(tsNode) ||
-    ts.isJsxOpeningElement(tsNode)
+    ts.isJsxOpeningElement(tsNode) ||
+    ts.isJsxSelfClosingElement(tsNode)
   ) {
     return getTypeParametersFromCall(node, tsNode, checker);
   }
@@ -193,6 +194,7 @@ function getTypeParametersFromCall(
   tsNode:
     | ts.CallExpression
     | ts.JsxOpeningElement
+    | ts.JsxSelfClosingElement
     | ts.NewExpression
     | ts.TaggedTemplateExpression,
   checker: ts.TypeChecker,
diff --git a/packages/eslint-plugin/tests/rules/no-unnecessary-type-arguments.test.ts b/packages/eslint-plugin/tests/rules/no-unnecessary-type-arguments.test.ts
index b5aaf6ca6437..18e74325d7b6 100644
--- a/packages/eslint-plugin/tests/rules/no-unnecessary-type-arguments.test.ts
+++ b/packages/eslint-plugin/tests/rules/no-unnecessary-type-arguments.test.ts
@@ -194,6 +194,21 @@ const button = <Button<string>></Button>;
         },
       },
     },
+    {
+      code: `
+function Button<T>() {
+  return <div></div>;
+}
+const button = <Button<string> />;
+      `,
+      languageOptions: {
+        parserOptions: {
+          ecmaFeatures: {
+            jsx: true,
+          },
+        },
+      },
+    },
   ],
   invalid: [
     {
@@ -602,5 +617,32 @@ function Button<T = string>() {
 const button = <Button></Button>;
       `,
     },
+    {
+      code: `
+function Button<T = string>() {
+  return <div></div>;
+}
+const button = <Button<string> />;
+      `,
+      errors: [
+        {
+          line: 5,
+          messageId: 'unnecessaryTypeParameter',
+        },
+      ],
+      languageOptions: {
+        parserOptions: {
+          ecmaFeatures: {
+            jsx: true,
+          },
+        },
+      },
+      output: `
+function Button<T = string>() {
+  return <div></div>;
+}
+const button = <Button />;
+      `,
+    },
   ],
 });