From ed784d68999f0a24e84fd48778e23e25f1c95ca4 Mon Sep 17 00:00:00 2001
From: Dominic Gannaway <dg@domgan.com>
Date: Fri, 28 Sep 2018 15:52:11 -0700
Subject: [PATCH] Add abstract support to Object.getOwnPropertySymbols (#2575)

Summary:
Release notes: none

Fixes https://github.com/facebook/prepack/issues/2574. This PR adds abstract value support to `Object.getOwnPropertySymbols` like we have done other internal methods (like `Object.keys` and `Array.from`) where we know the internal method creates an array with unknown numeric properties.
Pull Request resolved: https://github.com/facebook/prepack/pull/2575

Differential Revision: D10114237

Pulled By: trueadm

fbshipit-source-id: 07301147e2dff1ab370243a8dc9648745bbbbb96
---
 src/intrinsics/ecma262/Object.js              | 22 +++++++++-
 src/realm.js                                  |  4 +-
 src/serializer/functions.js                   |  2 +-
 .../optimizations/getOwnPropertySymbols.js    | 40 +++++++++++++++++++
 4 files changed, 63 insertions(+), 5 deletions(-)
 create mode 100644 test/serializer/optimizations/getOwnPropertySymbols.js

diff --git a/src/intrinsics/ecma262/Object.js b/src/intrinsics/ecma262/Object.js
index 233a3d3c5..dc91d392b 100644
--- a/src/intrinsics/ecma262/Object.js
+++ b/src/intrinsics/ecma262/Object.js
@@ -495,11 +495,29 @@ export default function(realm: Realm): NativeFunctionValue {
   });
 
   // ECMA262 19.1.2.9
-  if (!realm.isCompatibleWith(realm.MOBILE_JSC_VERSION) && !realm.isCompatibleWith("mobile"))
-    func.defineNativeMethod("getOwnPropertySymbols", 1, (context, [O]) => {
+  if (!realm.isCompatibleWith(realm.MOBILE_JSC_VERSION) && !realm.isCompatibleWith("mobile")) {
+    let getOwnPropertySymbols = func.defineNativeMethod("getOwnPropertySymbols", 1, (context, [O]) => {
+      if (O instanceof AbstractValue && realm.isInPureScope()) {
+        let obj = O instanceof AbstractObjectValue ? O : To.ToObject(realm, O);
+
+        realm.callReportObjectGetOwnProperties(obj);
+        return ArrayValue.createTemporalWithWidenedNumericProperty(
+          realm,
+          [getOwnPropertySymbols, obj],
+          createOperationDescriptor("UNKNOWN_ARRAY_METHOD_CALL")
+        );
+      } else if (ArrayValue.isIntrinsicAndHasWidenedNumericProperty(O)) {
+        realm.callReportObjectGetOwnProperties(O);
+        return ArrayValue.createTemporalWithWidenedNumericProperty(
+          realm,
+          [getOwnPropertySymbols, O],
+          createOperationDescriptor("UNKNOWN_ARRAY_METHOD_CALL")
+        );
+      }
       // Return ? GetOwnPropertyKeys(O, Symbol).
       return GetOwnPropertyKeys(realm, O, SymbolValue);
     });
+  }
 
   // ECMA262 19.1.2.10
   func.defineNativeMethod("getPrototypeOf", 1, (context, [O]) => {
diff --git a/src/realm.js b/src/realm.js
index f9938595d..ff70103c7 100644
--- a/src/realm.js
+++ b/src/realm.js
@@ -365,7 +365,7 @@ export class Realm {
   modifiedProperties: void | PropertyBindings;
   createdObjects: void | CreatedObjects;
   createdObjectsTrackedForLeaks: void | CreatedObjects;
-  reportObjectGetOwnProperties: void | (ObjectValue => void);
+  reportObjectGetOwnProperties: void | ((ObjectValue | AbstractObjectValue) => void);
   reportSideEffectCallbacks: Set<
     (sideEffectType: SideEffectType, binding: void | Binding | PropertyBinding, expressionLocation: any) => void
   >;
@@ -1491,7 +1491,7 @@ export class Realm {
     return binding;
   }
 
-  callReportObjectGetOwnProperties(ob: ObjectValue): void {
+  callReportObjectGetOwnProperties(ob: ObjectValue | AbstractObjectValue): void {
     if (this.reportObjectGetOwnProperties !== undefined) {
       this.reportObjectGetOwnProperties(ob);
     }
diff --git a/src/serializer/functions.js b/src/serializer/functions.js
index 84cab06ff..6ad8e069c 100644
--- a/src/serializer/functions.js
+++ b/src/serializer/functions.js
@@ -390,7 +390,7 @@ export class Functions {
       writtenObjects.add(key.object);
     });
     let oldReportObjectGetOwnProperties = this.realm.reportObjectGetOwnProperties;
-    this.realm.reportObjectGetOwnProperties = (ob: ObjectValue) => {
+    this.realm.reportObjectGetOwnProperties = (ob: ObjectValue | AbstractObjectValue) => {
       let location = this.realm.currentLocation;
       invariant(location);
       if (writtenObjects.has(ob) && !conflicts.has(location))
diff --git a/test/serializer/optimizations/getOwnPropertySymbols.js b/test/serializer/optimizations/getOwnPropertySymbols.js
new file mode 100644
index 000000000..32fbff41d
--- /dev/null
+++ b/test/serializer/optimizations/getOwnPropertySymbols.js
@@ -0,0 +1,40 @@
+function objectSpread(target) {
+  for (var i = 1; i < arguments.length; i++) {
+    var source = arguments[i] != null ? arguments[i] : {};
+    var ownKeys = Object.keys(source);
+
+    if (typeof Object.getOwnPropertySymbols === "function") {
+      ownKeys = ownKeys.concat(
+        Object.getOwnPropertySymbols(source).filter(function(sym) {
+          return Object.getOwnPropertyDescriptor(source, sym).enumerable;
+        })
+      );
+    }
+
+    ownKeys.forEach(function(key) {
+      babelHelpers.defineProperty(target, key, source[key]);
+    });
+  }
+
+  return target;
+}
+
+function fn(baseHeaders, contentEncoding, userAgent) {
+  var headers = objectSpread({}, baseHeaders);
+
+  if (contentEncoding) {
+    headers["Content-Encoding"] = contentEncoding;
+  }
+
+  if (userAgent) {
+    headers["User-Agent"] = userAgent;
+  }
+
+  return headers;
+}
+
+global.__optimize && __optimize(fn);
+
+inspect = function() {
+  return JSON.stringify(fn({ a: 1, b: 2 }, "123", "456"));
+};