LibJS: Start implementing Temporal.Calendar

Just like the previous Temporal.{Instant,TimeZone} commits, this patch
adds the Calendar object itself, its constructor and prototype
(currently empty), and two required abstract operations.

12 files changed, 250 insertions, 3 deletions

diff --git a/Userland/Libraries/LibJS/CMakeLists.txt b/Userland/Libraries/LibJS/CMakeLists.txt
index 921ce02bac..a289b85195 100644
--- a/Userland/Libraries/LibJS/CMakeLists.txt
+++ b/Userland/Libraries/LibJS/CMakeLists.txt
@@ -123,6 +123,8 @@ set(SOURCES
     Runtime/SymbolPrototype.cpp
     Runtime/Temporal/AbstractOperations.cpp
     Runtime/Temporal/Calendar.cpp
+    Runtime/Temporal/CalendarConstructor.cpp
+    Runtime/Temporal/CalendarPrototype.cpp
     Runtime/Temporal/Instant.cpp
     Runtime/Temporal/InstantConstructor.cpp
     Runtime/Temporal/InstantPrototype.cpp
diff --git a/Userland/Libraries/LibJS/Forward.h b/Userland/Libraries/LibJS/Forward.h
index 7df5cbec22..5032199e38 100644
--- a/Userland/Libraries/LibJS/Forward.h
+++ b/Userland/Libraries/LibJS/Forward.h
@@ -76,8 +76,9 @@
     __JS_ENUMERATE(Float32Array, float32_array, Float32ArrayPrototype, Float32ArrayConstructor, float)                          \
     __JS_ENUMERATE(Float64Array, float64_array, Float64ArrayPrototype, Float64ArrayConstructor, double)
 
-#define JS_ENUMERATE_TEMPORAL_OBJECTS                                      \
-    __JS_ENUMERATE(Instant, instant, InstantPrototype, InstantConstructor) \
+#define JS_ENUMERATE_TEMPORAL_OBJECTS                                          \
+    __JS_ENUMERATE(Calendar, calendar, CalendarPrototype, CalendarConstructor) \
+    __JS_ENUMERATE(Instant, instant, InstantPrototype, InstantConstructor)     \
     __JS_ENUMERATE(TimeZone, time_zone, TimeZonePrototype, TimeZoneConstructor)
 
 #define JS_ENUMERATE_ITERATOR_PROTOTYPES          \
diff --git a/Userland/Libraries/LibJS/Runtime/ErrorTypes.h b/Userland/Libraries/LibJS/Runtime/ErrorTypes.h
index ee685a5093..6220ae4f41 100644
--- a/Userland/Libraries/LibJS/Runtime/ErrorTypes.h
+++ b/Userland/Libraries/LibJS/Runtime/ErrorTypes.h
@@ -166,8 +166,9 @@
     M(StringNonGlobalRegExp, "RegExp argument is non-global")                                                                           \
     M(StringRawCannotConvert, "Cannot convert property 'raw' to object from {}")                                                        \
     M(StringRepeatCountMustBe, "repeat count must be a {} number")                                                                      \
-    M(TemporalInvalidISODate, "Invalid ISO date")                                                                                       \
+    M(TemporalInvalidCalendarIdentifier, "Invalid calendar identifier '{}'")                                                            \
     M(TemporalInvalidEpochNanoseconds, "Invalid epoch nanoseconds value, must be in range -86400 * 10^17 to 86400 * 10^17")             \
+    M(TemporalInvalidISODate, "Invalid ISO date")                                                                                       \
     M(TemporalInvalidTime, "Invalid time")                                                                                              \
     M(TemporalInvalidTimeZoneName, "Invalid time zone name")                                                                            \
     M(ThisHasNotBeenInitialized, "|this| has not been initialized")                                                                     \
diff --git a/Userland/Libraries/LibJS/Runtime/GlobalObject.cpp b/Userland/Libraries/LibJS/Runtime/GlobalObject.cpp
index 2b729d4deb..a56cff9e54 100644
--- a/Userland/Libraries/LibJS/Runtime/GlobalObject.cpp
+++ b/Userland/Libraries/LibJS/Runtime/GlobalObject.cpp
@@ -68,6 +68,8 @@
 #include <LibJS/Runtime/StringPrototype.h>
 #include <LibJS/Runtime/SymbolConstructor.h>
 #include <LibJS/Runtime/SymbolPrototype.h>
+#include <LibJS/Runtime/Temporal/CalendarConstructor.h>
+#include <LibJS/Runtime/Temporal/CalendarPrototype.h>
 #include <LibJS/Runtime/Temporal/InstantConstructor.h>
 #include <LibJS/Runtime/Temporal/InstantPrototype.h>
 #include <LibJS/Runtime/Temporal/Temporal.h>
diff --git a/Userland/Libraries/LibJS/Runtime/Temporal/Calendar.cpp b/Userland/Libraries/LibJS/Runtime/Temporal/Calendar.cpp
index f9948eea02..aa53db94bb 100644
--- a/Userland/Libraries/LibJS/Runtime/Temporal/Calendar.cpp
+++ b/Userland/Libraries/LibJS/Runtime/Temporal/Calendar.cpp
@@ -4,11 +4,55 @@
  * SPDX-License-Identifier: BSD-2-Clause
  */
 
+#include <LibJS/Runtime/AbstractOperations.h>
+#include <LibJS/Runtime/GlobalObject.h>
 #include <LibJS/Runtime/Temporal/Calendar.h>
+#include <LibJS/Runtime/Temporal/CalendarConstructor.h>
 #include <LibJS/Runtime/Value.h>
 
 namespace JS::Temporal {
 
+// 12 Temporal.Calendar Objects, https://tc39.es/proposal-temporal/#sec-temporal-calendar-objects
+Calendar::Calendar(String identifier, Object& prototype)
+    : Object(prototype)
+    , m_identifier(move(identifier))
+{
+}
+
+// 12.1.1 CreateTemporalCalendar ( identifier [ , newTarget ] ), https://tc39.es/proposal-temporal/#sec-temporal-createtemporalcalendar
+Calendar* create_temporal_calendar(GlobalObject& global_object, String const& identifier, FunctionObject* new_target)
+{
+    auto& vm = global_object.vm();
+
+    // 1. Assert: ! IsBuiltinCalendar(identifier) is true.
+    VERIFY(is_builtin_calendar(identifier));
+
+    // 2. If newTarget is not provided, set newTarget to %Temporal.Calendar%.
+    if (!new_target)
+        new_target = global_object.temporal_calendar_constructor();
+
+    // 3. Let object be ? OrdinaryCreateFromConstructor(newTarget, "%Temporal.Calendar.prototype%", « [[InitializedTemporalCalendar]], [[Identifier]] »).
+    // 4. Set object.[[Identifier]] to identifier.
+    auto* object = ordinary_create_from_constructor<Calendar>(global_object, *new_target, &GlobalObject::temporal_calendar_prototype, identifier);
+    if (vm.exception())
+        return {};
+
+    // 5. Return object.
+    return object;
+}
+
+// 12.1.2 IsBuiltinCalendar ( id ), https://tc39.es/proposal-temporal/#sec-temporal-isbuiltincalendar
+// NOTE: This is the minimum IsBuiltinCalendar implementation for engines without ECMA-402.
+bool is_builtin_calendar(String const& identifier)
+{
+    // 1. If id is not "iso8601", return false.
+    if (identifier != "iso8601"sv)
+        return false;
+
+    // 2. Return true.
+    return true;
+}
+
 // 12.1.30 IsISOLeapYear ( year ), https://tc39.es/proposal-temporal/#sec-temporal-isisoleapyear
 bool is_iso_leap_year(i32 year)
 {
diff --git a/Userland/Libraries/LibJS/Runtime/Temporal/Calendar.h b/Userland/Libraries/LibJS/Runtime/Temporal/Calendar.h
index edb742c566..e7b8ba1839 100644
--- a/Userland/Libraries/LibJS/Runtime/Temporal/Calendar.h
+++ b/Userland/Libraries/LibJS/Runtime/Temporal/Calendar.h
@@ -1,15 +1,35 @@
 /*
  * Copyright (c) 2021, Idan Horowitz <idan.horowitz@serenityos.org>
+ * Copyright (c) 2021, Linus Groh <linusg@serenityos.org>
  *
  * SPDX-License-Identifier: BSD-2-Clause
  */
 
 #pragma once
 
+#include <LibJS/Runtime/Object.h>
 #include <LibJS/Runtime/Value.h>
 
 namespace JS::Temporal {
 
+class Calendar final : public Object {
+    JS_OBJECT(Calendar, Object);
+
+public:
+    explicit Calendar(String identifier, Object& prototype);
+    virtual ~Calendar() override = default;
+
+    String const& identifier() const { return m_identifier; }
+
+private:
+    // 12.5 Properties of Temporal.Calendar Instances, https://tc39.es/proposal-temporal/#sec-properties-of-temporal-calendar-instances
+
+    // [[Identifier]]
+    String m_identifier;
+};
+
+Calendar* create_temporal_calendar(GlobalObject&, String const& identifier, FunctionObject* new_target = nullptr);
+bool is_builtin_calendar(String const& identifier);
 bool is_iso_leap_year(i32 year);
 i32 iso_days_in_month(i32 year, i32 month);
 
diff --git a/Userland/Libraries/LibJS/Runtime/Temporal/CalendarConstructor.cpp b/Userland/Libraries/LibJS/Runtime/Temporal/CalendarConstructor.cpp
new file mode 100644
index 0000000000..c4b6b5863f
--- /dev/null
+++ b/Userland/Libraries/LibJS/Runtime/Temporal/CalendarConstructor.cpp
@@ -0,0 +1,64 @@
+/*
+ * Copyright (c) 2021, Linus Groh <linusg@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <LibJS/Runtime/GlobalObject.h>
+#include <LibJS/Runtime/Temporal/Calendar.h>
+#include <LibJS/Runtime/Temporal/CalendarConstructor.h>
+
+namespace JS::Temporal {
+
+// 12.2 The Temporal.Calendar Constructor, https://tc39.es/proposal-temporal/#sec-temporal-calendar-constructor
+CalendarConstructor::CalendarConstructor(GlobalObject& global_object)
+    : NativeFunction(vm().names.Calendar.as_string(), *global_object.function_prototype())
+{
+}
+
+void CalendarConstructor::initialize(GlobalObject& global_object)
+{
+    NativeFunction::initialize(global_object);
+
+    auto& vm = this->vm();
+
+    // 12.3.1 Temporal.Calendar.prototype, https://tc39.es/proposal-temporal/#sec-temporal-calendar-prototype
+    define_direct_property(vm.names.prototype, global_object.temporal_calendar_prototype(), 0);
+
+    define_direct_property(vm.names.length, Value(1), Attribute::Configurable);
+}
+
+// 12.2.1 Temporal.Calendar ( id ), https://tc39.es/proposal-temporal/#sec-temporal.calendar
+Value CalendarConstructor::call()
+{
+    auto& vm = this->vm();
+
+    // 1. If NewTarget is undefined, then
+    // a. Throw a TypeError exception.
+    vm.throw_exception<TypeError>(global_object(), ErrorType::ConstructorWithoutNew, "Temporal.Calendar");
+    return {};
+}
+
+// 12.2.1 Temporal.Calendar ( id ), https://tc39.es/proposal-temporal/#sec-temporal.calendar
+Value CalendarConstructor::construct(FunctionObject& new_target)
+{
+    auto& vm = this->vm();
+    auto& global_object = this->global_object();
+
+    // 2. Set id to ? ToString(id).
+    auto identifier = vm.argument(0).to_string(global_object);
+    if (vm.exception())
+        return {};
+
+    // 3. If ! IsBuiltinCalendar(id) is false, then
+    if (!is_builtin_calendar(identifier)) {
+        // a. Throw a RangeError exception.
+        vm.throw_exception<RangeError>(global_object, ErrorType::TemporalInvalidCalendarIdentifier, identifier);
+        return {};
+    }
+
+    // 4. Return ? CreateTemporalCalendar(id, NewTarget).
+    return create_temporal_calendar(global_object, identifier, &new_target);
+}
+
+}
diff --git a/Userland/Libraries/LibJS/Runtime/Temporal/CalendarConstructor.h b/Userland/Libraries/LibJS/Runtime/Temporal/CalendarConstructor.h
new file mode 100644
index 0000000000..5ce91aaa72
--- /dev/null
+++ b/Userland/Libraries/LibJS/Runtime/Temporal/CalendarConstructor.h
@@ -0,0 +1,28 @@
+/*
+ * Copyright (c) 2021, Linus Groh <linusg@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <LibJS/Runtime/NativeFunction.h>
+
+namespace JS::Temporal {
+
+class CalendarConstructor final : public NativeFunction {
+    JS_OBJECT(CalendarConstructor, NativeFunction);
+
+public:
+    explicit CalendarConstructor(GlobalObject&);
+    virtual void initialize(GlobalObject&) override;
+    virtual ~CalendarConstructor() override = default;
+
+    virtual Value call() override;
+    virtual Value construct(FunctionObject& new_target) override;
+
+private:
+    virtual bool has_constructor() const override { return true; }
+};
+
+}
diff --git a/Userland/Libraries/LibJS/Runtime/Temporal/CalendarPrototype.cpp b/Userland/Libraries/LibJS/Runtime/Temporal/CalendarPrototype.cpp
new file mode 100644
index 0000000000..d362658085
--- /dev/null
+++ b/Userland/Libraries/LibJS/Runtime/Temporal/CalendarPrototype.cpp
@@ -0,0 +1,23 @@
+/*
+ * Copyright (c) 2021, Linus Groh <linusg@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <LibJS/Runtime/GlobalObject.h>
+#include <LibJS/Runtime/Temporal/CalendarPrototype.h>
+
+namespace JS::Temporal {
+
+// 12.4 Properties of the Temporal.Calendar Prototype Object, https://tc39.es/proposal-temporal/#sec-properties-of-the-temporal-calendar-prototype-object
+CalendarPrototype::CalendarPrototype(GlobalObject& global_object)
+    : Object(*global_object.object_prototype())
+{
+}
+
+void CalendarPrototype::initialize(GlobalObject& global_object)
+{
+    Object::initialize(global_object);
+}
+
+}
diff --git a/Userland/Libraries/LibJS/Runtime/Temporal/CalendarPrototype.h b/Userland/Libraries/LibJS/Runtime/Temporal/CalendarPrototype.h
new file mode 100644
index 0000000000..4f17d1b68f
--- /dev/null
+++ b/Userland/Libraries/LibJS/Runtime/Temporal/CalendarPrototype.h
@@ -0,0 +1,22 @@
+/*
+ * Copyright (c) 2021, Linus Groh <linusg@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <LibJS/Runtime/Object.h>
+
+namespace JS::Temporal {
+
+class CalendarPrototype final : public Object {
+    JS_OBJECT(CalendarPrototype, Object);
+
+public:
+    explicit CalendarPrototype(GlobalObject&);
+    virtual void initialize(GlobalObject&) override;
+    virtual ~CalendarPrototype() override = default;
+};
+
+}
diff --git a/Userland/Libraries/LibJS/Runtime/Temporal/Temporal.cpp b/Userland/Libraries/LibJS/Runtime/Temporal/Temporal.cpp
index b35583c7ab..83c208fb71 100644
--- a/Userland/Libraries/LibJS/Runtime/Temporal/Temporal.cpp
+++ b/Userland/Libraries/LibJS/Runtime/Temporal/Temporal.cpp
@@ -5,6 +5,7 @@
  */
 
 #include <LibJS/Runtime/GlobalObject.h>
+#include <LibJS/Runtime/Temporal/CalendarConstructor.h>
 #include <LibJS/Runtime/Temporal/InstantConstructor.h>
 #include <LibJS/Runtime/Temporal/Now.h>
 #include <LibJS/Runtime/Temporal/Temporal.h>
@@ -26,6 +27,7 @@ void Temporal::initialize(GlobalObject& global_object)
     u8 attr = Attribute::Writable | Attribute::Configurable;
 
     define_direct_property(vm.names.now, heap().allocate<Now>(global_object, global_object), attr);
+    define_direct_property(vm.names.Calendar, global_object.temporal_calendar_constructor(), attr);
     define_direct_property(vm.names.Instant, global_object.temporal_instant_constructor(), attr);
     define_direct_property(vm.names.TimeZone, global_object.temporal_time_zone_constructor(), attr);
 }
diff --git a/Userland/Libraries/LibJS/Tests/builtins/Temporal/Calendar/Calendar.js b/Userland/Libraries/LibJS/Tests/builtins/Temporal/Calendar/Calendar.js
new file mode 100644
index 0000000000..4ddefcf3d7
--- /dev/null
+++ b/Userland/Libraries/LibJS/Tests/builtins/Temporal/Calendar/Calendar.js
@@ -0,0 +1,38 @@
+describe("errors", () => {
+    test("called without new", () => {
+        expect(() => {
+            Temporal.Calendar();
+        }).toThrowWithMessage(TypeError, "Temporal.Calendar constructor must be called with 'new'");
+    });
+
+    test("argument must be coercible to string", () => {
+        expect(() => {
+            new Temporal.Calendar({
+                toString() {
+                    throw new Error();
+                },
+            });
+        }).toThrow(Error);
+    });
+
+    test("invalid calendar identifier", () => {
+        expect(() => {
+            new Temporal.Calendar("foo");
+        }).toThrowWithMessage(RangeError, "Invalid calendar identifier 'foo'");
+    });
+});
+
+describe("normal behavior", () => {
+    test("length is 1", () => {
+        expect(Temporal.Calendar).toHaveLength(1);
+    });
+
+    test("basic functionality", () => {
+        const calendar = new Temporal.Calendar("iso8601");
+        // FIXME: Enable this once Temporal.Calendar.prototype.id is implemented
+        // expect(calendar.id).toBe("iso8601");
+        expect(typeof calendar).toBe("object");
+        expect(calendar).toBeInstanceOf(Temporal.Calendar);
+        expect(Object.getPrototypeOf(calendar)).toBe(Temporal.Calendar.prototype);
+    });
+});