Use IEEE 754 semantics for NaN (Issue #1084)

2 files changed, 99 insertions, 1 deletions

diff --git a/src/test/run-pass/float-nan.rs b/src/test/run-pass/float-nan.rs
new file mode 100644
index 00000000000..61ef4373a8c
--- /dev/null
+++ b/src/test/run-pass/float-nan.rs
@@ -0,0 +1,74 @@
+use std;
+import std::float;
+
+fn main() {
+  let nan = float::NaN();
+  assert(float::isNaN(nan));
+
+  let inf = float::infinity();
+  assert(-inf == float::neg_infinity());
+
+  assert( nan !=  nan);
+  assert( nan != -nan);
+  assert(-nan != -nan);
+  assert(-nan !=  nan);
+
+  assert( nan !=   1.);
+  assert( nan !=   0.);
+  assert( nan !=  inf);
+  assert( nan != -inf);
+
+  assert(  1. !=  nan);
+  assert(  0. !=  nan);
+  assert( inf !=  nan);
+  assert(-inf !=  nan);
+
+  assert(!( nan ==  nan));
+  assert(!( nan == -nan));
+  assert(!( nan ==   1.));
+  assert(!( nan ==   0.));
+  assert(!( nan ==  inf));
+  assert(!( nan == -inf));
+  assert(!(  1. ==  nan));
+  assert(!(  0. ==  nan));
+  assert(!( inf ==  nan));
+  assert(!(-inf ==  nan));
+  assert(!(-nan ==  nan));
+  assert(!(-nan == -nan));
+
+  assert(!( nan >  nan));
+  assert(!( nan > -nan));
+  assert(!( nan >   0.));
+  assert(!( nan >  inf));
+  assert(!( nan > -inf));
+  assert(!(  0. >  nan));
+  assert(!( inf >  nan));
+  assert(!(-inf >  nan));
+  assert(!(-nan >  nan));
+
+  assert(!(nan <   0.));
+  assert(!(nan <   1.));
+  assert(!(nan <  -1.));
+  assert(!(nan <  inf));
+  assert(!(nan < -inf));
+  assert(!(nan <  nan));
+  assert(!(nan < -nan));
+
+  assert(!(  0. < nan));
+  assert(!(  1. < nan));
+  assert(!( -1. < nan));
+  assert(!( inf < nan));
+  assert(!(-inf < nan));
+  assert(!(-nan < nan));
+
+  assert(float::isNaN(nan + inf));
+  assert(float::isNaN(nan + -inf));
+  assert(float::isNaN(nan + 0.));
+  assert(float::isNaN(nan + 1.));
+  assert(float::isNaN(nan * 1.));
+  assert(float::isNaN(nan / 1.));
+  assert(float::isNaN(nan / 0.));
+  assert(float::isNaN(0. / 0.));
+  assert(float::isNaN(-inf + inf));
+  assert(float::isNaN(inf - inf));
+}
diff --git a/src/test/stdtest/float.rs b/src/test/stdtest/float.rs
index 086942fb8c1..302d6b1679e 100644
--- a/src/test/stdtest/float.rs
+++ b/src/test/stdtest/float.rs
@@ -10,7 +10,7 @@ fn test_from_str() {
    assert ( float::from_str("2.5e10") == 25000000000. );
    assert ( float::from_str("25000000000.E-10") == 2.5 );
    assert ( float::from_str("") == 0. );
-   assert ( float::from_str("   ") == 0. );
+   assert ( float::isNaN(float::from_str("   ")) );
    assert ( float::from_str(".") == 0. );
    assert ( float::from_str("5.") == 5. );
    assert ( float::from_str(".5") == 0.5 );
@@ -25,6 +25,7 @@ fn test_positive() {
   assert(!float::positive(-1.));
   assert(!float::positive(float::neg_infinity()));
   assert(!float::positive(1./float::neg_infinity()));
+  assert(!float::positive(float::NaN()));
 }
 
 #[test]
@@ -35,4 +36,27 @@ fn test_negative() {
   assert(float::negative(-1.));
   assert(float::negative(float::neg_infinity()));
   assert(float::negative(1./float::neg_infinity()));
+  assert(!float::negative(float::NaN()));
+}
+
+#[test]
+fn test_nonpositive() {
+  assert(!float::nonpositive(float::infinity()));
+  assert(!float::nonpositive(1.));
+  assert(!float::nonpositive(0.));
+  assert(float::nonpositive(-1.));
+  assert(float::nonpositive(float::neg_infinity()));
+  assert(float::nonpositive(1./float::neg_infinity()));
+  // TODO: assert(!float::nonpositive(float::NaN()));
+}
+
+#[test]
+fn test_nonnegative() {
+  assert(float::nonnegative(float::infinity()));
+  assert(float::nonnegative(1.));
+  assert(float::nonnegative(0.));
+  assert(!float::nonnegative(-1.));
+  assert(!float::nonnegative(float::neg_infinity()));
+  assert(!float::nonnegative(1./float::neg_infinity()));
+  // TODO: assert(!float::nonnegative(float::NaN()));
 }