Rollup merge of #146152 - rperier:unify_and_dedup_algebraic_float_tests, r=tgross35

Unify and deduplicate algebraic float tests

cc rust-lang/rust#141726

This is a proposal to unify and deduplicate the algebraic tests for f16, f32, f64 and f128

5 files changed, 44 insertions, 83 deletions

diff --git a/library/coretests/tests/floats/f128.rs b/library/coretests/tests/floats/f128.rs
index c173d7f0ae0..4267fef50f8 100644
--- a/library/coretests/tests/floats/f128.rs
+++ b/library/coretests/tests/floats/f128.rs
@@ -1,7 +1,9 @@
 // FIXME(f16_f128): only tested on platforms that have symbols and aren't buggy
 #![cfg(target_has_reliable_f128)]
 
-use super::{assert_approx_eq, assert_biteq};
+#[cfg(any(miri, target_has_reliable_f128_math))]
+use super::assert_approx_eq;
+use super::assert_biteq;
 
 // Note these tolerances make sense around zero, but not for more extreme exponents.
 
@@ -75,25 +77,6 @@ fn test_float_bits_conv() {
 }
 
 #[test]
-fn test_algebraic() {
-    let a: f128 = 123.0;
-    let b: f128 = 456.0;
-
-    // Check that individual operations match their primitive counterparts.
-    //
-    // This is a check of current implementations and does NOT imply any form of
-    // guarantee about future behavior. The compiler reserves the right to make
-    // these operations inexact matches in the future.
-    let eps = if cfg!(miri) { 1e-6 } else { 0.0 };
-
-    assert_approx_eq!(a.algebraic_add(b), a + b, eps);
-    assert_approx_eq!(a.algebraic_sub(b), a - b, eps);
-    assert_approx_eq!(a.algebraic_mul(b), a * b, eps);
-    assert_approx_eq!(a.algebraic_div(b), a / b, eps);
-    assert_approx_eq!(a.algebraic_rem(b), a % b, eps);
-}
-
-#[test]
 fn test_from() {
     assert_biteq!(f128::from(false), 0.0);
     assert_biteq!(f128::from(true), 1.0);
diff --git a/library/coretests/tests/floats/f16.rs b/library/coretests/tests/floats/f16.rs
index c12de7221ba..d2818a6d768 100644
--- a/library/coretests/tests/floats/f16.rs
+++ b/library/coretests/tests/floats/f16.rs
@@ -74,27 +74,6 @@ fn test_float_bits_conv() {
 }
 
 #[test]
-fn test_algebraic() {
-    let a: f16 = 123.0;
-    let b: f16 = 456.0;
-
-    // Check that individual operations match their primitive counterparts.
-    //
-    // This is a check of current implementations and does NOT imply any form of
-    // guarantee about future behavior. The compiler reserves the right to make
-    // these operations inexact matches in the future.
-    let eps_add = if cfg!(miri) { 1e1 } else { 0.0 };
-    let eps_mul = if cfg!(miri) { 1e3 } else { 0.0 };
-    let eps_div = if cfg!(miri) { 1e0 } else { 0.0 };
-
-    assert_approx_eq!(a.algebraic_add(b), a + b, eps_add);
-    assert_approx_eq!(a.algebraic_sub(b), a - b, eps_add);
-    assert_approx_eq!(a.algebraic_mul(b), a * b, eps_mul);
-    assert_approx_eq!(a.algebraic_div(b), a / b, eps_div);
-    assert_approx_eq!(a.algebraic_rem(b), a % b, eps_div);
-}
-
-#[test]
 fn test_from() {
     assert_biteq!(f16::from(false), 0.0);
     assert_biteq!(f16::from(true), 1.0);
diff --git a/library/coretests/tests/floats/f32.rs b/library/coretests/tests/floats/f32.rs
index b79295f470d..7b25f354da4 100644
--- a/library/coretests/tests/floats/f32.rs
+++ b/library/coretests/tests/floats/f32.rs
@@ -1,6 +1,6 @@
 use core::f32;
 
-use super::{assert_approx_eq, assert_biteq};
+use super::assert_biteq;
 
 /// First pattern over the mantissa
 const NAN_MASK1: u32 = 0x002a_aaaa;
@@ -47,24 +47,3 @@ fn test_float_bits_conv() {
     assert_eq!(f32::from_bits(masked_nan1).to_bits(), masked_nan1);
     assert_eq!(f32::from_bits(masked_nan2).to_bits(), masked_nan2);
 }
-
-#[test]
-fn test_algebraic() {
-    let a: f32 = 123.0;
-    let b: f32 = 456.0;
-
-    // Check that individual operations match their primitive counterparts.
-    //
-    // This is a check of current implementations and does NOT imply any form of
-    // guarantee about future behavior. The compiler reserves the right to make
-    // these operations inexact matches in the future.
-    let eps_add = if cfg!(miri) { 1e-3 } else { 0.0 };
-    let eps_mul = if cfg!(miri) { 1e-1 } else { 0.0 };
-    let eps_div = if cfg!(miri) { 1e-4 } else { 0.0 };
-
-    assert_approx_eq!(a.algebraic_add(b), a + b, eps_add);
-    assert_approx_eq!(a.algebraic_sub(b), a - b, eps_add);
-    assert_approx_eq!(a.algebraic_mul(b), a * b, eps_mul);
-    assert_approx_eq!(a.algebraic_div(b), a / b, eps_div);
-    assert_approx_eq!(a.algebraic_rem(b), a % b, eps_div);
-}
diff --git a/library/coretests/tests/floats/f64.rs b/library/coretests/tests/floats/f64.rs
index a2540586328..099d85627a3 100644
--- a/library/coretests/tests/floats/f64.rs
+++ b/library/coretests/tests/floats/f64.rs
@@ -1,6 +1,6 @@
 use core::f64;
 
-use super::{assert_approx_eq, assert_biteq};
+use super::assert_biteq;
 
 /// First pattern over the mantissa
 const NAN_MASK1: u64 = 0x000a_aaaa_aaaa_aaaa;
@@ -46,22 +46,3 @@ fn test_float_bits_conv() {
     assert_eq!(f64::from_bits(masked_nan1).to_bits(), masked_nan1);
     assert_eq!(f64::from_bits(masked_nan2).to_bits(), masked_nan2);
 }
-
-#[test]
-fn test_algebraic() {
-    let a: f64 = 123.0;
-    let b: f64 = 456.0;
-
-    // Check that individual operations match their primitive counterparts.
-    //
-    // This is a check of current implementations and does NOT imply any form of
-    // guarantee about future behavior. The compiler reserves the right to make
-    // these operations inexact matches in the future.
-    let eps = if cfg!(miri) { 1e-6 } else { 0.0 };
-
-    assert_approx_eq!(a.algebraic_add(b), a + b, eps);
-    assert_approx_eq!(a.algebraic_sub(b), a - b, eps);
-    assert_approx_eq!(a.algebraic_mul(b), a * b, eps);
-    assert_approx_eq!(a.algebraic_div(b), a / b, eps);
-    assert_approx_eq!(a.algebraic_rem(b), a % b, eps);
-}
diff --git a/library/coretests/tests/floats/mod.rs b/library/coretests/tests/floats/mod.rs
index 5f59cb9cce3..c0439845a4a 100644
--- a/library/coretests/tests/floats/mod.rs
+++ b/library/coretests/tests/floats/mod.rs
@@ -27,6 +27,9 @@ trait TestableFloat: Sized {
     const NAN_MASK1: Self::Int;
     /// Second pattern over the mantissa
     const NAN_MASK2: Self::Int;
+    const EPS_ADD: Self;
+    const EPS_MUL: Self;
+    const EPS_DIV: Self;
 }
 
 impl TestableFloat for f16 {
@@ -44,6 +47,9 @@ impl TestableFloat for f16 {
     const MAX_DOWN: Self = Self::from_bits(0x7bfe);
     const NAN_MASK1: Self::Int = 0x02aa;
     const NAN_MASK2: Self::Int = 0x0155;
+    const EPS_ADD: Self = if cfg!(miri) { 1e1 } else { 0.0 };
+    const EPS_MUL: Self = if cfg!(miri) { 1e3 } else { 0.0 };
+    const EPS_DIV: Self = if cfg!(miri) { 1e0 } else { 0.0 };
 }
 
 impl TestableFloat for f32 {
@@ -63,6 +69,9 @@ impl TestableFloat for f32 {
     const MAX_DOWN: Self = Self::from_bits(0x7f7f_fffe);
     const NAN_MASK1: Self::Int = 0x002a_aaaa;
     const NAN_MASK2: Self::Int = 0x0055_5555;
+    const EPS_ADD: Self = if cfg!(miri) { 1e-3 } else { 0.0 };
+    const EPS_MUL: Self = if cfg!(miri) { 1e-1 } else { 0.0 };
+    const EPS_DIV: Self = if cfg!(miri) { 1e-4 } else { 0.0 };
 }
 
 impl TestableFloat for f64 {
@@ -78,6 +87,9 @@ impl TestableFloat for f64 {
     const MAX_DOWN: Self = Self::from_bits(0x7fef_ffff_ffff_fffe);
     const NAN_MASK1: Self::Int = 0x000a_aaaa_aaaa_aaaa;
     const NAN_MASK2: Self::Int = 0x0005_5555_5555_5555;
+    const EPS_ADD: Self = if cfg!(miri) { 1e-6 } else { 0.0 };
+    const EPS_MUL: Self = if cfg!(miri) { 1e-6 } else { 0.0 };
+    const EPS_DIV: Self = if cfg!(miri) { 1e-6 } else { 0.0 };
 }
 
 impl TestableFloat for f128 {
@@ -93,6 +105,9 @@ impl TestableFloat for f128 {
     const MAX_DOWN: Self = Self::from_bits(0x7ffefffffffffffffffffffffffffffe);
     const NAN_MASK1: Self::Int = 0x0000aaaaaaaaaaaaaaaaaaaaaaaaaaaa;
     const NAN_MASK2: Self::Int = 0x00005555555555555555555555555555;
+    const EPS_ADD: Self = if cfg!(miri) { 1e-6 } else { 0.0 };
+    const EPS_MUL: Self = if cfg!(miri) { 1e-6 } else { 0.0 };
+    const EPS_DIV: Self = if cfg!(miri) { 1e-6 } else { 0.0 };
 }
 
 /// Determine the tolerance for values of the argument type.
@@ -1440,3 +1455,27 @@ float_test! {
         assert_biteq!(neg_inf.to_radians(), neg_inf);
     }
 }
+
+float_test! {
+    name: to_algebraic,
+    attrs: {
+        f16: #[cfg(target_has_reliable_f16)],
+        f128: #[cfg(target_has_reliable_f128)],
+    },
+    test<Float> {
+        let a: Float = 123.0;
+        let b: Float = 456.0;
+
+        // Check that individual operations match their primitive counterparts.
+        //
+        // This is a check of current implementations and does NOT imply any form of
+        // guarantee about future behavior. The compiler reserves the right to make
+        // these operations inexact matches in the future.
+
+        assert_approx_eq!(a.algebraic_add(b), a + b, Float::EPS_ADD);
+        assert_approx_eq!(a.algebraic_sub(b), a - b, Float::EPS_ADD);
+        assert_approx_eq!(a.algebraic_mul(b), a * b, Float::EPS_MUL);
+        assert_approx_eq!(a.algebraic_div(b), a / b, Float::EPS_DIV);
+        assert_approx_eq!(a.algebraic_rem(b), a % b, Float::EPS_DIV);
+    }
+}