From 47286f78f21b421e4a0a51169f35c2eb5f08892f Mon Sep 17 00:00:00 2001
From: oxyu8 <liberalist0449@gmail.com>
Date: Sat, 22 Apr 2023 22:10:49 +0900
Subject: [PATCH] change: [unified-signatures] check every b.params[i]

---
 packages/eslint-plugin/src/rules/unified-signatures.ts     | 4 +---
 .../eslint-plugin/tests/rules/unified-signatures.test.ts   | 7 +++++++
 2 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/packages/eslint-plugin/src/rules/unified-signatures.ts b/packages/eslint-plugin/src/rules/unified-signatures.ts
index 5fb841bc8bd..8d8cda0e378 100644
--- a/packages/eslint-plugin/src/rules/unified-signatures.ts
+++ b/packages/eslint-plugin/src/rules/unified-signatures.ts
@@ -213,11 +213,9 @@ export default util.createRule<Options, MessageIds>({
         b.typeParameters !== undefined ? b.typeParameters.params : undefined;
 
       if (ignoreDifferentlyNamedParameters) {
-        if (b.params.length === 0) {
-          return false;
-        }
         for (let i = 0; i < a.params.length; i += 1) {
           if (
+            b.params[i] &&
             a.params[i].type === b.params[i].type &&
             getStaticParameterName(a.params[i]) !==
               getStaticParameterName(b.params[i])
diff --git a/packages/eslint-plugin/tests/rules/unified-signatures.test.ts b/packages/eslint-plugin/tests/rules/unified-signatures.test.ts
index 2de59aaa3b4..ce62f6c571c 100644
--- a/packages/eslint-plugin/tests/rules/unified-signatures.test.ts
+++ b/packages/eslint-plugin/tests/rules/unified-signatures.test.ts
@@ -184,6 +184,13 @@ function f(): string;
     },
     {
       code: `
+function f(v: boolean, u: boolean): number;
+function f(v: boolean): string;
+      `,
+      options: [{ ignoreDifferentlyNamedParameters: true }],
+    },
+    {
+      code: `
 function f(v: number, u?: string): void {}
 function f(v: number): void;
 function f(): string;