Improve GetFunctionRealm coverage (#2155)

* Fix Function.prototype.bind test

* Simplify Proxy test

* Info tweaks

* Add Function.prototype.bind recursive test

* Add Proxy recursive test

test/built-ins/Function/prototype/bind/get-fn-realm-recursive.js

@@ -0,0 +1,25 @@
+// Copyright (C) 2019 Aleksey Shvayka. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-getfunctionrealm
+description: >
+    The realm of a bound function exotic object is the realm of its target
+    function. GetFunctionRealm is called recursively.
+info: |
+    7.3.22 GetFunctionRealm ( obj )
+
+    [...]
+    2. If obj has a [[Realm]] internal slot, then
+       a. Return obj.[[Realm]].
+    3. If obj is a Bound Function exotic object, then
+       a. Let target be obj.[[BoundTargetFunction]].
+       b. Return ? GetFunctionRealm(target).
+features: [cross-realm]
+---*/
+
+var other = $262.createRealm().global;
+var C = new other.Function();
+C.prototype = null;
+var B = C.bind().bind();
+
+assert.sameValue(Object.getPrototypeOf(new B()), other.Object.prototype);

test/built-ins/Function/prototype/bind/get-fn-realm.js

@@ -7,17 +7,20 @@ description: >
     The realm of a bound function exotic object is the realm of its target
     function
 info: |
+    7.3.22 GetFunctionRealm ( obj )
+
     [...]
     2. If obj has a [[Realm]] internal slot, then
-       a, Return obj's [[Realm]] internal slot.
+       a. Return obj.[[Realm]].
     3. If obj is a Bound Function exotic object, then
-       a. Let target be obj's [[BoundTargetFunction]] internal slot.
+       a. Let target be obj.[[BoundTargetFunction]].
        b. Return ? GetFunctionRealm(target).
 features: [cross-realm]
 ---*/
 
 var other = $262.createRealm().global;
 var C = new other.Function();
-var B = Function.prototype.bind.call(C);
+C.prototype = null;
+var B = C.bind();
 
-assert.sameValue(Object.getPrototypeOf(new B()), C.prototype);
+assert.sameValue(Object.getPrototypeOf(new B()), other.Object.prototype);

test/built-ins/Proxy/get-fn-realm-recursive.js

@@ -0,0 +1,27 @@
+// Copyright (C) 2019 Aleksey Shvayka. All rights reserved.
+// This code is governed by the BSD license found in the LICENSE file.
+/*---
+esid: sec-getfunctionrealm
+description: >
+    The realm of a proxy exotic object is the realm of its target function.
+    GetFunctionRealm is called recursively.
+info: |
+    7.3.22 GetFunctionRealm ( obj )
+
+    [...]
+    2. If obj has a [[Realm]] internal slot, then
+       a. Return obj.[[Realm]].
+    [...]
+    4. If obj is a Proxy exotic object, then
+       a. If obj.[[ProxyHandler]] is null, throw a TypeError exception.
+       b. Let proxyTarget be obj.[[ProxyTarget]].
+       c. Return ? GetFunctionRealm(proxyTarget).
+features: [cross-realm, Proxy]
+---*/
+
+var other = $262.createRealm().global;
+var C = new other.Function();
+C.prototype = null;
+var P = new Proxy(new Proxy(C, {}), {});
+
+assert.sameValue(Object.getPrototypeOf(new P()), other.Object.prototype);

test/built-ins/Proxy/get-fn-realm.js

@@ -6,24 +6,22 @@ es6id: 7.3.22
 description: >
     The realm of a proxy exotic object is the realm of its target function
 info: |
+    7.3.22 GetFunctionRealm ( obj )
+
     [...]
     2. If obj has a [[Realm]] internal slot, then
-       a, Return obj's [[Realm]] internal slot.
-    3. If obj is a Bound Function exotic object, then
-       [...]
+       a. Return obj.[[Realm]].
+    [...]
     4. If obj is a Proxy exotic object, then
-       a. If the value of the [[ProxyHandler]] internal slot of obj is null,
-          throw a TypeError exception.
-       b. Let proxyTarget be the value of obj's [[ProxyTarget]] internal slot.
+       a. If obj.[[ProxyHandler]] is null, throw a TypeError exception.
+       b. Let proxyTarget be obj.[[ProxyTarget]].
        c. Return ? GetFunctionRealm(proxyTarget).
 features: [cross-realm, Proxy]
 ---*/
 
 var other = $262.createRealm().global;
 var C = new other.Function();
-// Ensure that the proxy does not report a `prototype` property
-var P = new Proxy(C, {
-  get: function() {}
-});
+C.prototype = null;
+var P = new Proxy(C, {});
 
 assert.sameValue(Object.getPrototypeOf(new P()), other.Object.prototype);