require-array-join-separator: Check optional member (#1569)

Author: fisker

rules/require-array-join-separator.js

@@ -9,7 +9,11 @@ const messages = {
 
 const selector = matches([
 	// `foo.join()`
-	methodCallSelector({method: 'join', argumentsLength: 0}),
+	methodCallSelector({
+		method: 'join',
+		argumentsLength: 0,
+		includeOptionalMember: true,
+	}),
 	// `[].join.call(foo)` and `Array.prototype.join.call(foo)`
 	[
 		methodCallSelector({method: 'call', argumentsLength: 1}),

test/require-array-join-separator.mjs

@@ -8,7 +8,8 @@ test.snapshot({
 		'foo.join(",")',
 		'join()',
 		'foo.join(...[])',
-		'foo?.join()',
+		'foo.join?.()',
+		'foo?.join?.()',
 		'foo[join]()',
 		'foo["join"]()',
 		'[].join.call(foo, ",")',
@@ -71,5 +72,6 @@ test.snapshot({
 					)/**/
 			)
 		`,
+		'foo?.join()',
 	],
 });

test/snapshots/require-array-join-separator.mjs.md

@@ -192,3 +192,19 @@ Generated by [AVA](https://avajs.dev).
          | ^^^^ Missing the separator argument.␊
       26 | )␊
     `
+
+## Invalid #8
+      1 | foo?.join()
+
+> Output
+
+    `␊
+      1 | foo?.join(',')␊
+    `
+
+> Error 1/1
+
+    `␊
+    > 1 | foo?.join()␊
+        |          ^^ Missing the separator argument.␊
+    `