From d3bed13f4ba7c105bc96119c8d498b2dd35a240a Mon Sep 17 00:00:00 2001
From: Linus Groh <mail@linusgroh.de>
Date: Wed, 28 Jul 2021 19:07:29 +0100
Subject: [PATCH] LibJS: Implement Temporal.PlainTime.prototype.nanosecond

---
 .../Libraries/LibJS/Runtime/CommonPropertyNames.h  |  1 +
 .../LibJS/Runtime/Temporal/PlainTimePrototype.cpp  | 14 ++++++++++++++
 .../LibJS/Runtime/Temporal/PlainTimePrototype.h    |  1 +
 .../PlainTime/PlainTime.prototype.nanosecond.js    | 14 ++++++++++++++
 4 files changed, 30 insertions(+)
 create mode 100644 Userland/Libraries/LibJS/Tests/builtins/Temporal/PlainTime/PlainTime.prototype.nanosecond.js

diff --git a/Userland/Libraries/LibJS/Runtime/CommonPropertyNames.h b/Userland/Libraries/LibJS/Runtime/CommonPropertyNames.h
index 12861d0a67..1ee234dafe 100644
--- a/Userland/Libraries/LibJS/Runtime/CommonPropertyNames.h
+++ b/Userland/Libraries/LibJS/Runtime/CommonPropertyNames.h
@@ -275,6 +275,7 @@ namespace JS {
     P(monthsInYear)                          \
     P(multiline)                             \
     P(name)                                  \
+    P(nanosecond)                            \
     P(nanoseconds)                           \
     P(negated)                               \
     P(next)                                  \
diff --git a/Userland/Libraries/LibJS/Runtime/Temporal/PlainTimePrototype.cpp b/Userland/Libraries/LibJS/Runtime/Temporal/PlainTimePrototype.cpp
index a1b152c61e..b233444e25 100644
--- a/Userland/Libraries/LibJS/Runtime/Temporal/PlainTimePrototype.cpp
+++ b/Userland/Libraries/LibJS/Runtime/Temporal/PlainTimePrototype.cpp
@@ -32,6 +32,7 @@ void PlainTimePrototype::initialize(GlobalObject& global_object)
     define_native_accessor(vm.names.second, second_getter, {}, Attribute::Configurable);
     define_native_accessor(vm.names.millisecond, millisecond_getter, {}, Attribute::Configurable);
     define_native_accessor(vm.names.microsecond, microsecond_getter, {}, Attribute::Configurable);
+    define_native_accessor(vm.names.nanosecond, nanosecond_getter, {}, Attribute::Configurable);
 
     u8 attr = Attribute::Writable | Attribute::Configurable;
     define_native_function(vm.names.valueOf, value_of, 0, attr);
@@ -128,6 +129,19 @@ JS_DEFINE_NATIVE_FUNCTION(PlainTimePrototype::microsecond_getter)
     return Value(temporal_time->iso_microsecond());
 }
 
+// 4.3.9 get Temporal.PlainTime.prototype.nanosecond, https://tc39.es/proposal-temporal/#sec-get-temporal.plaintime.prototype.nanosecond
+JS_DEFINE_NATIVE_FUNCTION(PlainTimePrototype::nanosecond_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 𝔽(temporalTime.[[ISONanosecond]]).
+    return Value(temporal_time->iso_nanosecond());
+}
+
 // 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 f6eb822b49..4c1694a019 100644
--- a/Userland/Libraries/LibJS/Runtime/Temporal/PlainTimePrototype.h
+++ b/Userland/Libraries/LibJS/Runtime/Temporal/PlainTimePrototype.h
@@ -25,6 +25,7 @@ private:
     JS_DECLARE_NATIVE_FUNCTION(second_getter);
     JS_DECLARE_NATIVE_FUNCTION(millisecond_getter);
     JS_DECLARE_NATIVE_FUNCTION(microsecond_getter);
+    JS_DECLARE_NATIVE_FUNCTION(nanosecond_getter);
     JS_DECLARE_NATIVE_FUNCTION(value_of);
 };
 
diff --git a/Userland/Libraries/LibJS/Tests/builtins/Temporal/PlainTime/PlainTime.prototype.nanosecond.js b/Userland/Libraries/LibJS/Tests/builtins/Temporal/PlainTime/PlainTime.prototype.nanosecond.js
new file mode 100644
index 0000000000..5f9923e27f
--- /dev/null
+++ b/Userland/Libraries/LibJS/Tests/builtins/Temporal/PlainTime/PlainTime.prototype.nanosecond.js
@@ -0,0 +1,14 @@
+describe("correct behavior", () => {
+    test("basic functionality", () => {
+        const plainTime = new Temporal.PlainTime(0, 0, 0, 0, 0, 12);
+        expect(plainTime.nanosecond).toBe(12);
+    });
+});
+
+test("errors", () => {
+    test("this value must be a Temporal.PlainTime object", () => {
+        expect(() => {
+            Reflect.get(Temporal.PlainTime.prototype, "nanosecond", "foo");
+        }).toThrowWithMessage(TypeError, "Not a Temporal.PlainTime");
+    });
+});