fix(eslint-plugin): [unbound-method] false positive on property function initializer (typescript-eslint#1890)

vapurrmaid · web-flow · commit f1c3b18f7aad · 2020-04-13T09:28:56.000-07:00
diff --git a/packages/eslint-plugin/src/rules/unbound-method.ts b/packages/eslint-plugin/src/rules/unbound-method.ts
@@ -198,6 +198,11 @@ function isDangerousMethod(symbol: ts.Symbol, ignoreStatic: boolean): boolean {
   }
 
   switch (valueDeclaration.kind) {
+    case ts.SyntaxKind.PropertyDeclaration:
+      return (
+        (valueDeclaration as ts.PropertyDeclaration).initializer?.kind ===
+        ts.SyntaxKind.FunctionExpression
+      );
     case ts.SyntaxKind.MethodDeclaration:
     case ts.SyntaxKind.MethodSignature:
       return !(
diff --git a/packages/eslint-plugin/tests/rules/unbound-method.test.ts b/packages/eslint-plugin/tests/rules/unbound-method.test.ts
@@ -367,5 +367,19 @@ instance.unbound = x; // THIS SHOULD NOT
         },
       ],
     },
+    {
+      code: `
+class Foo {
+  unbound = function() {};
+}
+const unbound = new Foo().unbound;
+      `,
+      errors: [
+        {
+          line: 5,
+          messageId: 'unbound',
+        },
+      ],
+    },
   ],
 });
