add Invocation of the instance's then method test

test/built-ins/Promise/any/invoke-then.js

@@ -0,0 +1,53 @@
+// Copyright (C) 2019 Sergey Rubanov. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+
+/*---
+description: >
+  Invocation of the instance's `then` method
+esid: sec-promise.any
+info: |
+  5. Let result be PerformPromiseAny(iteratorRecord, C, promiseCapability).
+  6. If result is an abrupt completion, then
+    a. If iteratorRecord.[[Done]] is false, set result to IteratorClose(iteratorRecord, result).
+    b. IfAbruptRejectPromise(result, promiseCapability).
+
+  Runtime Semantics: PerformPromiseAny
+
+  r. Perform ? Invoke(nextPromise, "then", « resultCapability.[[Resolve]], rejectElement »).
+features: [Promise.any]
+---*/
+
+var p1 = new Promise(function() {});
+var p2 = new Promise(function() {});
+var p3 = new Promise(function() {});
+var callCount = 0;
+var currentThis = p1;
+var nextThis = p2;
+var afterNextThis = p3;
+
+p1.then = p2.then = p3.then = function(a, b) {
+  assert.sameValue(typeof a, 'function', 'type of first argument');
+  assert.sameValue(
+    a.length,
+    1,
+    'The length property of a promise resolve function is 1.'
+  );
+  assert.sameValue(typeof b, 'function', 'type of second argument');
+  assert.sameValue(
+    b.length,
+    1,
+    'The length property of a promise reject function is 1.'
+  );
+  assert.sameValue(arguments.length, 2, '`then` invoked with two arguments');
+  assert.sameValue(this, currentThis, '`this` value');
+
+  currentThis = nextThis;
+  nextThis = afterNextThis;
+  afterNextThis = null;
+
+  callCount += 1;
+};
+
+Promise.any([p1, p2, p3]);
+
+assert.sameValue(callCount, 3, '`then` invoked once for every iterated value');