Merge pull request rust-lang/libm#221 from Lokathor/tests

slightly improve spec and sanity check coverage

8 files changed, 171 insertions, 5 deletions

diff --git a/library/compiler-builtins/libm/src/math/ceil.rs b/library/compiler-builtins/libm/src/math/ceil.rs
index 63c1121c6d3..eda28b9a0f2 100644
--- a/library/compiler-builtins/libm/src/math/ceil.rs
+++ b/library/compiler-builtins/libm/src/math/ceil.rs
@@ -42,9 +42,22 @@ pub fn ceil(x: f64) -> f64 {
 
 #[cfg(test)]
 mod tests {
+    use super::*;
+    use core::f64::*;
+
     #[test]
     fn sanity_check() {
-        assert_eq!(super::ceil(1.1), 2.0);
-        assert_eq!(super::ceil(2.9), 3.0);
+        assert_eq!(ceil(1.1), 2.0);
+        assert_eq!(ceil(2.9), 3.0);
+    }
+
+    /// The spec: https://en.cppreference.com/w/cpp/numeric/math/ceil
+    #[test]
+    fn spec_tests() {
+        // Not Asserted: that the current rounding mode has no effect.
+        assert!(ceil(NAN).is_nan());
+        for f in [0.0, -0.0, INFINITY, NEG_INFINITY].iter().copied() {
+            assert_eq!(ceil(f), f);
+        }
     }
 }
diff --git a/library/compiler-builtins/libm/src/math/ceilf.rs b/library/compiler-builtins/libm/src/math/ceilf.rs
index 87d96982aab..f1edbd061bf 100644
--- a/library/compiler-builtins/libm/src/math/ceilf.rs
+++ b/library/compiler-builtins/libm/src/math/ceilf.rs
@@ -39,3 +39,25 @@ pub fn ceilf(x: f32) -> f32 {
     }
     f32::from_bits(ui)
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use core::f32::*;
+
+    #[test]
+    fn sanity_check() {
+        assert_eq!(ceilf(1.1), 2.0);
+        assert_eq!(ceilf(2.9), 3.0);
+    }
+
+    /// The spec: https://en.cppreference.com/w/cpp/numeric/math/ceil
+    #[test]
+    fn spec_tests() {
+        // Not Asserted: that the current rounding mode has no effect.
+        assert!(ceilf(NAN).is_nan());
+        for f in [0.0, -0.0, INFINITY, NEG_INFINITY].iter().copied() {
+            assert_eq!(ceilf(f), f);
+        }
+    }
+}
diff --git a/library/compiler-builtins/libm/src/math/fabs.rs b/library/compiler-builtins/libm/src/math/fabs.rs
index 5a7f795f6a3..b2255ad32cf 100644
--- a/library/compiler-builtins/libm/src/math/fabs.rs
+++ b/library/compiler-builtins/libm/src/math/fabs.rs
@@ -15,3 +15,27 @@ pub fn fabs(x: f64) -> f64 {
     }
     f64::from_bits(x.to_bits() & (u64::MAX / 2))
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use core::f64::*;
+
+    #[test]
+    fn sanity_check() {
+        assert_eq!(fabs(-1.0), 1.0);
+        assert_eq!(fabs(2.8), 2.8);
+    }
+
+    /// The spec: https://en.cppreference.com/w/cpp/numeric/math/fabs
+    #[test]
+    fn spec_tests() {
+        assert!(fabs(NAN).is_nan());
+        for f in [0.0, -0.0].iter().copied() {
+            assert_eq!(fabs(f), 0.0);
+        }
+        for f in [INFINITY, NEG_INFINITY].iter().copied() {
+            assert_eq!(fabs(f), INFINITY);
+        }
+    }
+}
diff --git a/library/compiler-builtins/libm/src/math/fabsf.rs b/library/compiler-builtins/libm/src/math/fabsf.rs
index 495512584d2..6655c4c3ccc 100644
--- a/library/compiler-builtins/libm/src/math/fabsf.rs
+++ b/library/compiler-builtins/libm/src/math/fabsf.rs
@@ -13,3 +13,27 @@ pub fn fabsf(x: f32) -> f32 {
     }
     f32::from_bits(x.to_bits() & 0x7fffffff)
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use core::f32::*;
+
+    #[test]
+    fn sanity_check() {
+        assert_eq!(fabsf(-1.0), 1.0);
+        assert_eq!(fabsf(2.8), 2.8);
+    }
+
+    /// The spec: https://en.cppreference.com/w/cpp/numeric/math/fabs
+    #[test]
+    fn spec_tests() {
+        assert!(fabsf(NAN).is_nan());
+        for f in [0.0, -0.0].iter().copied() {
+            assert_eq!(fabsf(f), 0.0);
+        }
+        for f in [INFINITY, NEG_INFINITY].iter().copied() {
+            assert_eq!(fabsf(f), INFINITY);
+        }
+    }
+}
diff --git a/library/compiler-builtins/libm/src/math/floor.rs b/library/compiler-builtins/libm/src/math/floor.rs
index 91825e3c88f..b2b760570de 100644
--- a/library/compiler-builtins/libm/src/math/floor.rs
+++ b/library/compiler-builtins/libm/src/math/floor.rs
@@ -38,3 +38,25 @@ pub fn floor(x: f64) -> f64 {
         x + y
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use core::f64::*;
+
+    #[test]
+    fn sanity_check() {
+        assert_eq!(floor(1.1), 1.0);
+        assert_eq!(floor(2.9), 2.0);
+    }
+
+    /// The spec: https://en.cppreference.com/w/cpp/numeric/math/floor
+    #[test]
+    fn spec_tests() {
+        // Not Asserted: that the current rounding mode has no effect.
+        assert!(floor(NAN).is_nan());
+        for f in [0.0, -0.0, INFINITY, NEG_INFINITY].iter().copied() {
+            assert_eq!(floor(f), f);
+        }
+    }
+}
diff --git a/library/compiler-builtins/libm/src/math/floorf.rs b/library/compiler-builtins/libm/src/math/floorf.rs
index 6d751b077ef..287f0864277 100644
--- a/library/compiler-builtins/libm/src/math/floorf.rs
+++ b/library/compiler-builtins/libm/src/math/floorf.rs
@@ -42,8 +42,23 @@ pub fn floorf(x: f32) -> f32 {
 
 #[cfg(test)]
 mod tests {
+    use super::*;
+    use core::f32::*;
+
     #[test]
-    fn no_overflow() {
-        assert_eq!(super::floorf(0.5), 0.0);
+    fn sanity_check() {
+        assert_eq!(floorf(0.5), 0.0);
+        assert_eq!(floorf(1.1), 1.0);
+        assert_eq!(floorf(2.9), 2.0);
+    }
+
+    /// The spec: https://en.cppreference.com/w/cpp/numeric/math/floor
+    #[test]
+    fn spec_tests() {
+        // Not Asserted: that the current rounding mode has no effect.
+        assert!(floorf(NAN).is_nan());
+        for f in [0.0, -0.0, INFINITY, NEG_INFINITY].iter().copied() {
+            assert_eq!(floorf(f), f);
+        }
     }
 }
diff --git a/library/compiler-builtins/libm/src/math/sqrt.rs b/library/compiler-builtins/libm/src/math/sqrt.rs
index 31afe33566b..f06b209a49f 100644
--- a/library/compiler-builtins/libm/src/math/sqrt.rs
+++ b/library/compiler-builtins/libm/src/math/sqrt.rs
@@ -37,7 +37,7 @@
  *      If (2) is false, then q   = q ; otherwise q   = q  + 2      .
  *                             i+1   i             i+1   i
  *
- *      With some algebric manipulation, it is not difficult to see
+ *      With some algebraic manipulation, it is not difficult to see
  *      that (2) is equivalent to
  *                             -(i+1)
  *                      s  +  2       <= y                      (3)
@@ -239,3 +239,26 @@ pub fn sqrt(x: f64) -> f64 {
         f64::from_bits((ix0 as u64) << 32 | ix1.0 as u64)
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use core::f64::*;
+
+    #[test]
+    fn sanity_check() {
+        assert_eq!(sqrt(100.0), 10.0);
+        assert_eq!(sqrt(4.0), 2.0);
+    }
+
+    /// The spec: https://en.cppreference.com/w/cpp/numeric/math/sqrt
+    #[test]
+    fn spec_tests() {
+        // Not Asserted: FE_INVALID exception is raised if argument is negative.
+        assert!(sqrt(-1.0).is_nan());
+        assert!(sqrt(NAN).is_nan());
+        for f in [0.0, -0.0, INFINITY].iter().copied() {
+            assert_eq!(sqrt(f), f);
+        }
+    }
+}
diff --git a/library/compiler-builtins/libm/src/math/sqrtf.rs b/library/compiler-builtins/libm/src/math/sqrtf.rs
index 1d5b78e84c6..ee868c8c811 100644
--- a/library/compiler-builtins/libm/src/math/sqrtf.rs
+++ b/library/compiler-builtins/libm/src/math/sqrtf.rs
@@ -127,3 +127,26 @@ pub fn sqrtf(x: f32) -> f32 {
         f32::from_bits(ix as u32)
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use core::f32::*;
+
+    #[test]
+    fn sanity_check() {
+        assert_eq!(sqrtf(100.0), 10.0);
+        assert_eq!(sqrtf(4.0), 2.0);
+    }
+
+    /// The spec: https://en.cppreference.com/w/cpp/numeric/math/sqrt
+    #[test]
+    fn spec_tests() {
+        // Not Asserted: FE_INVALID exception is raised if argument is negative.
+        assert!(sqrtf(-1.0).is_nan());
+        assert!(sqrtf(NAN).is_nan());
+        for f in [0.0, -0.0, INFINITY].iter().copied() {
+            assert_eq!(sqrtf(f), f);
+        }
+    }
+}