From a8dd1b9480b150dd3e36e299b3b6a6e24a496fa3 Mon Sep 17 00:00:00 2001
From: Linus Groh <mail@linusgroh.de>
Date: Wed, 28 Jul 2021 18:48:35 +0100
Subject: [PATCH] LibJS: Implement Temporal.PlainTime.prototype.calendar

---
 .../Runtime/Temporal/PlainTimePrototype.cpp   | 30 +++++++++++++++++++
 .../Runtime/Temporal/PlainTimePrototype.h     |  1 +
 .../PlainTime/PlainTime.prototype.calendar.js | 15 ++++++++++
 3 files changed, 46 insertions(+)
 create mode 100644 Userland/Libraries/LibJS/Tests/builtins/Temporal/PlainTime/PlainTime.prototype.calendar.js

diff --git a/Userland/Libraries/LibJS/Runtime/Temporal/PlainTimePrototype.cpp b/Userland/Libraries/LibJS/Runtime/Temporal/PlainTimePrototype.cpp
index 5ec0b77935..6d6ddaeb75 100644
--- a/Userland/Libraries/LibJS/Runtime/Temporal/PlainTimePrototype.cpp
+++ b/Userland/Libraries/LibJS/Runtime/Temporal/PlainTimePrototype.cpp
@@ -5,6 +5,8 @@
  */
 
 #include <LibJS/Runtime/GlobalObject.h>
+#include <LibJS/Runtime/Temporal/Calendar.h>
+#include <LibJS/Runtime/Temporal/PlainTime.h>
 #include <LibJS/Runtime/Temporal/PlainTimePrototype.h>
 
 namespace JS::Temporal {
@@ -24,10 +26,38 @@ void PlainTimePrototype::initialize(GlobalObject& global_object)
     // 4.3.2 Temporal.PlainTime.prototype[ @@toStringTag ], https://tc39.es/proposal-temporal/#sec-temporal.plaintime.prototype-@@tostringtag
     define_direct_property(*vm.well_known_symbol_to_string_tag(), js_string(vm.heap(), "Temporal.PlainTime"), Attribute::Configurable);
 
+    define_native_accessor(vm.names.calendar, calendar_getter, {}, Attribute::Configurable);
+
     u8 attr = Attribute::Writable | Attribute::Configurable;
     define_native_function(vm.names.valueOf, value_of, 0, attr);
 }
 
+static PlainTime* typed_this(GlobalObject& global_object)
+{
+    auto& vm = global_object.vm();
+    auto* this_object = vm.this_value(global_object).to_object(global_object);
+    if (!this_object)
+        return {};
+    if (!is<PlainTime>(this_object)) {
+        vm.throw_exception<TypeError>(global_object, ErrorType::NotA, "Temporal.PlainTime");
+        return {};
+    }
+    return static_cast<PlainTime*>(this_object);
+}
+
+// 4.3.3 get Temporal.PlainTime.prototype.calendar, https://tc39.es/proposal-temporal/#sec-get-temporal.plaintime.prototype.calendar
+JS_DEFINE_NATIVE_FUNCTION(PlainTimePrototype::calendar_getter)
+{
+    // 1. Let temporalTime be the this value.
+    // 2. Perform ? RequireInternalSlot(temporalTime, [[InitializedTemporalTime]]).
+    auto* temporal_time = typed_this(global_object);
+    if (vm.exception())
+        return {};
+
+    // 3. Return temporalTime.[[Calendar]].
+    return Value(&temporal_time->calendar());
+}
+
 // 4.3.23 Temporal.PlainTime.prototype.valueOf ( ), https://tc39.es/proposal-temporal/#sec-temporal.plaintime.prototype.valueof
 JS_DEFINE_NATIVE_FUNCTION(PlainTimePrototype::value_of)
 {
diff --git a/Userland/Libraries/LibJS/Runtime/Temporal/PlainTimePrototype.h b/Userland/Libraries/LibJS/Runtime/Temporal/PlainTimePrototype.h
index b9793df22e..4c05717b60 100644
--- a/Userland/Libraries/LibJS/Runtime/Temporal/PlainTimePrototype.h
+++ b/Userland/Libraries/LibJS/Runtime/Temporal/PlainTimePrototype.h
@@ -19,6 +19,7 @@ public:
     virtual ~PlainTimePrototype() override = default;
 
 private:
+    JS_DECLARE_NATIVE_FUNCTION(calendar_getter);
     JS_DECLARE_NATIVE_FUNCTION(value_of);
 };
 
diff --git a/Userland/Libraries/LibJS/Tests/builtins/Temporal/PlainTime/PlainTime.prototype.calendar.js b/Userland/Libraries/LibJS/Tests/builtins/Temporal/PlainTime/PlainTime.prototype.calendar.js
new file mode 100644
index 0000000000..815f76b566
--- /dev/null
+++ b/Userland/Libraries/LibJS/Tests/builtins/Temporal/PlainTime/PlainTime.prototype.calendar.js
@@ -0,0 +1,15 @@
+describe("correct behavior", () => {
+    test("basic functionality", () => {
+        const plainTime = new Temporal.PlainTime();
+        expect(plainTime.calendar).toBeInstanceOf(Temporal.Calendar);
+        expect(plainTime.calendar.id).toBe("iso8601");
+    });
+});
+
+test("errors", () => {
+    test("this value must be a Temporal.PlainTime object", () => {
+        expect(() => {
+            Reflect.get(Temporal.PlainTime.prototype, "calendar", "foo");
+        }).toThrowWithMessage(TypeError, "Not a Temporal.PlainTime");
+    });
+});