From 9b9bc127548db6e2f9b17bafec64e5ab3c898625 Mon Sep 17 00:00:00 2001
From: auvred <aauvred@gmail.com>
Date: Fri, 21 Jul 2023 21:47:54 +0000
Subject: [PATCH 1/2] fix(eslint-plugin): [non-nullable-type-assertion-style]
 consider operator precedence when fixing

---
 .../non-nullable-type-assertion-style.ts      | 12 ++++++-
 .../non-nullable-type-assertion-style.test.ts | 36 +++++++++++++++++++
 2 files changed, 47 insertions(+), 1 deletion(-)

diff --git a/packages/eslint-plugin/src/rules/non-nullable-type-assertion-style.ts b/packages/eslint-plugin/src/rules/non-nullable-type-assertion-style.ts
index 2cfdd7ea1f88..69189417943d 100644
--- a/packages/eslint-plugin/src/rules/non-nullable-type-assertion-style.ts
+++ b/packages/eslint-plugin/src/rules/non-nullable-type-assertion-style.ts
@@ -117,11 +117,21 @@ export default util.createRule({
         }
 
         if (sameTypeWithoutNullish(assertedTypes, originalTypes)) {
+          const expressionSourceCode = sourceCode.getText(node.expression);
+
+          const higherPrecedenceThanUnary =
+            util.getOperatorPrecedence(
+              services.esTreeNodeToTSNodeMap.get(node.expression).kind,
+              ts.SyntaxKind.Unknown,
+            ) > util.OperatorPrecedence.Unary;
+
           context.report({
             fix(fixer) {
               return fixer.replaceText(
                 node,
-                `${sourceCode.getText(node.expression)}!`,
+                higherPrecedenceThanUnary
+                  ? `${expressionSourceCode}!`
+                  : `(${expressionSourceCode})!`,
               );
             },
             messageId: 'preferNonNullAssertion',
diff --git a/packages/eslint-plugin/tests/rules/non-nullable-type-assertion-style.test.ts b/packages/eslint-plugin/tests/rules/non-nullable-type-assertion-style.test.ts
index 8b86634d2797..0171b1f14514 100644
--- a/packages/eslint-plugin/tests/rules/non-nullable-type-assertion-style.test.ts
+++ b/packages/eslint-plugin/tests/rules/non-nullable-type-assertion-style.test.ts
@@ -199,6 +199,42 @@ declare const x: T;
 const y = x!;
       `,
     },
+    {
+      code: `
+declare function nullablePromise(): Promise<string | null>;
+
+async function fn(): Promise<string> {
+  return (await nullablePromise()) as string;
+}
+
+declare const a: string | null;
+
+const b = (a || undefined) as string;
+      `,
+      errors: [
+        {
+          column: 10,
+          line: 5,
+          messageId: 'preferNonNullAssertion',
+        },
+        {
+          column: 11,
+          line: 10,
+          messageId: 'preferNonNullAssertion',
+        },
+      ],
+      output: `
+declare function nullablePromise(): Promise<string | null>;
+
+async function fn(): Promise<string> {
+  return (await nullablePromise())!;
+}
+
+declare const a: string | null;
+
+const b = (a || undefined)!;
+      `,
+    },
   ],
 });
 

From 78fe250eb39edfd8c5f2ef8541498248fd691f6c Mon Sep 17 00:00:00 2001
From: auvred <aauvred@gmail.com>
Date: Wed, 26 Jul 2023 15:30:22 +0000
Subject: [PATCH 2/2] test: split huge test case

---
 .../non-nullable-type-assertion-style.test.ts | 24 ++++++++++++-------
 1 file changed, 15 insertions(+), 9 deletions(-)

diff --git a/packages/eslint-plugin/tests/rules/non-nullable-type-assertion-style.test.ts b/packages/eslint-plugin/tests/rules/non-nullable-type-assertion-style.test.ts
index 0171b1f14514..a5dd34cb94aa 100644
--- a/packages/eslint-plugin/tests/rules/non-nullable-type-assertion-style.test.ts
+++ b/packages/eslint-plugin/tests/rules/non-nullable-type-assertion-style.test.ts
@@ -206,10 +206,6 @@ declare function nullablePromise(): Promise<string | null>;
 async function fn(): Promise<string> {
   return (await nullablePromise()) as string;
 }
-
-declare const a: string | null;
-
-const b = (a || undefined) as string;
       `,
       errors: [
         {
@@ -217,11 +213,6 @@ const b = (a || undefined) as string;
           line: 5,
           messageId: 'preferNonNullAssertion',
         },
-        {
-          column: 11,
-          line: 10,
-          messageId: 'preferNonNullAssertion',
-        },
       ],
       output: `
 declare function nullablePromise(): Promise<string | null>;
@@ -229,7 +220,22 @@ declare function nullablePromise(): Promise<string | null>;
 async function fn(): Promise<string> {
   return (await nullablePromise())!;
 }
+      `,
+    },
+    {
+      code: `
+declare const a: string | null;
 
+const b = (a || undefined) as string;
+      `,
+      errors: [
+        {
+          column: 11,
+          line: 4,
+          messageId: 'preferNonNullAssertion',
+        },
+      ],
+      output: `
 declare const a: string | null;
 
 const b = (a || undefined)!;