From 37f8e9a2460cc10ee975f900b11af0fc55ca1406 Mon Sep 17 00:00:00 2001
From: Conrad Pankoff <deoxxa@fknsrs.biz>
Date: Tue, 17 Dec 2019 17:34:20 +1100
Subject: [PATCH] support Number.isNaN

---
 builtin_number.go |  7 +++++++
 builtin_test.go   | 11 +++++++++++
 inline.go         | 31 +++++++++++++++++++++++++++++++
 inline.pl         |  1 +
 4 files changed, 50 insertions(+)

diff --git a/builtin_number.go b/builtin_number.go
index f99a42a..9f11ef6 100644
--- a/builtin_number.go
+++ b/builtin_number.go
@@ -88,6 +88,13 @@ func builtinNumber_toPrecision(call FunctionCall) Value {
 	return toValue_string(strconv.FormatFloat(call.This.float64(), 'g', int(precision), 64))
 }
 
+func builtinNumber_isNaN(call FunctionCall) Value {
+	if len(call.ArgumentList) < 1 {
+		return toValue_bool(false)
+	}
+	return toValue_bool(call.Argument(0).IsNaN())
+}
+
 func builtinNumber_toLocaleString(call FunctionCall) Value {
 	return builtinNumber_toString(call)
 }
diff --git a/builtin_test.go b/builtin_test.go
index f5be00a..dd76dcd 100644
--- a/builtin_test.go
+++ b/builtin_test.go
@@ -134,3 +134,14 @@ func TestGlobal_unescape(t *testing.T) {
         `, "abc,==,abc=%+32,世界")
 	})
 }
+
+func TestNumber_isNaN(t *testing.T) {
+	tt(t, func() {
+		test, _ := test()
+		test(`Number.isNaN(1)`, false)
+		test(`Number.isNaN(null)`, false)
+		test(`Number.isNaN()`, false)
+		test(`Number.isNaN(Number.NaN)`, true)
+		test(`Number.isNaN(0+undefined)`, true)
+	})
+}
diff --git a/inline.go b/inline.go
index 6e5df83..149ffd8 100644
--- a/inline.go
+++ b/inline.go
@@ -2627,6 +2627,29 @@ func _newContext(runtime *_runtime) {
 				call: builtinNumber_toLocaleString,
 			},
 		}
+		isNaN_function := &_object{
+			runtime:     runtime,
+			class:       "Function",
+			objectClass: _classObject,
+			prototype:   runtime.global.FunctionPrototype,
+			extensible:  true,
+			property: map[string]_property{
+				"length": _property{
+					mode: 0,
+					value: Value{
+						kind:  valueNumber,
+						value: 1,
+					},
+				},
+			},
+			propertyOrder: []string{
+				"length",
+			},
+			value: _nativeFunctionObject{
+				name: "isNaN",
+				call: builtinNumber_isNaN,
+			},
+		}
 		runtime.global.NumberPrototype = &_object{
 			runtime:     runtime,
 			class:       "Number",
@@ -2713,6 +2736,13 @@ func _newContext(runtime *_runtime) {
 						value: runtime.global.NumberPrototype,
 					},
 				},
+				"isNaN": _property{
+					mode: 0101,
+					value: Value{
+						kind:  valueObject,
+						value: isNaN_function,
+					},
+				},
 				"MAX_VALUE": _property{
 					mode: 0,
 					value: Value{
@@ -2752,6 +2782,7 @@ func _newContext(runtime *_runtime) {
 			propertyOrder: []string{
 				"length",
 				"prototype",
+				"isNaN",
 				"MAX_VALUE",
 				"MIN_VALUE",
 				"NaN",
diff --git a/inline.pl b/inline.pl
index e902904..e21444d 100755
--- a/inline.pl
+++ b/inline.pl
@@ -372,6 +372,7 @@ sub newContext {
                 1,
                 $self->functionDeclare(
                     $class,
+                    "isNaN", 1,
                 ),
                 $self->numberConstantDeclare(
                     "MAX_VALUE", "math.MaxFloat64",