From bacbd85543965911cdcf221d232559ae07c05c35 Mon Sep 17 00:00:00 2001
From: Bob Nystrom <robert@stuffwithstuff.com>
Date: Wed, 30 Sep 2015 08:41:43 -0700
Subject: [PATCH] Add .isInfinity and .isInteger to Num.

---
 doc/site/core/num.markdown        | 16 ++++++++++++++++
 src/vm/wren_core.c                | 14 ++++++++++++++
 test/core/number/is_infinity.wren |  3 +++
 test/core/number/is_integer.wren  | 11 +++++++++++
 4 files changed, 44 insertions(+)
 create mode 100644 test/core/number/is_infinity.wren
 create mode 100644 test/core/number/is_integer.wren

diff --git a/doc/site/core/num.markdown b/doc/site/core/num.markdown
index 41e058ce..a0bdc375 100644
--- a/doc/site/core/num.markdown
+++ b/doc/site/core/num.markdown
@@ -60,6 +60,22 @@ Rounds the number down to the nearest integer.
     1.5.floor    // 1
     (-3.2).floor // -4
 
+### **isInfinity**
+
+Whether the number is positive or negative infinity or not.
+
+    :::wren
+    99999.isInfinity  // false
+    (1/0).isInfinity  // true
+
+### **isInteger**
+
+Whether the number is an integer or has some fractional component.
+
+    :::wren
+    2.isInteger   // true
+    2.3.isInteger // false
+
 ### **isNan**
 
 Whether the number is [not a number](http://en.wikipedia.org/wiki/NaN). This is
diff --git a/src/vm/wren_core.c b/src/vm/wren_core.c
index ab3f1a30..eb9e3dd7 100644
--- a/src/vm/wren_core.c
+++ b/src/vm/wren_core.c
@@ -665,6 +665,18 @@ DEF_PRIMITIVE(num_fraction)
   RETURN_NUM(modf(AS_NUM(args[0]) , &dummy));
 }
 
+DEF_PRIMITIVE(num_isInfinity)
+{
+  RETURN_BOOL(isinf(AS_NUM(args[0])));
+}
+
+DEF_PRIMITIVE(num_isInteger)
+{
+  double value = AS_NUM(args[0]);
+  if (isnan(value) || isinf(value)) RETURN_FALSE;
+  RETURN_BOOL(trunc(value) == value);
+}
+
 DEF_PRIMITIVE(num_isNan)
 {
   RETURN_BOOL(isnan(AS_NUM(args[0])));
@@ -1194,6 +1206,8 @@ void wrenInitializeCore(WrenVM* vm)
   PRIMITIVE(vm->numClass, "...(_)", num_dotDotDot);
   PRIMITIVE(vm->numClass, "atan(_)", num_atan2);
   PRIMITIVE(vm->numClass, "fraction", num_fraction);
+  PRIMITIVE(vm->numClass, "isInfinity", num_isInfinity);
+  PRIMITIVE(vm->numClass, "isInteger", num_isInteger);
   PRIMITIVE(vm->numClass, "isNan", num_isNan);
   PRIMITIVE(vm->numClass, "sign", num_sign);
   PRIMITIVE(vm->numClass, "toString", num_toString);
diff --git a/test/core/number/is_infinity.wren b/test/core/number/is_infinity.wren
new file mode 100644
index 00000000..5f503a18
--- /dev/null
+++ b/test/core/number/is_infinity.wren
@@ -0,0 +1,3 @@
+System.print(123.isInfinity) // expect: false
+System.print((1/0).isInfinity)  // expect: true
+System.print((-10/0).isInfinity)  // expect: true
diff --git a/test/core/number/is_integer.wren b/test/core/number/is_integer.wren
new file mode 100644
index 00000000..0eb76fca
--- /dev/null
+++ b/test/core/number/is_integer.wren
@@ -0,0 +1,11 @@
+System.print(123.isInteger) // expect: true
+System.print(123.0.isInteger) // expect: true
+System.print(0.isInteger) // expect: true
+System.print(1.0000001.isInteger) // expect: false
+System.print((-2.3).isInteger) // expect: false
+
+// NaN is not an integer.
+System.print((0/0).isInteger) // expect: false
+
+// Infinity is not an integer.
+System.print((1/0).isInteger)  // expect: false