Merge pull request #19316 from arubiales/quit_runtimewarning_moduleop_

BUG: Fix warning problems of the mod operator

3 files changed, 51 insertions, 90 deletions

diff --git a/numpy/core/src/npymath/npy_math_internal.h.src b/numpy/core/src/npymath/npy_math_internal.h.src
index ff4663dc3..1e46a2303 100644
--- a/numpy/core/src/npymath/npy_math_internal.h.src
+++ b/numpy/core/src/npymath/npy_math_internal.h.src
@@ -398,8 +398,8 @@ NPY_INPLACE @type@ npy_@kind@@c@(@type@ x)
 /**end repeat1**/
 
 /**begin repeat1
- * #kind = atan2,hypot,pow,copysign#
- * #KIND = ATAN2,HYPOT,POW,COPYSIGN#
+ * #kind = atan2,hypot,pow,fmod,copysign#
+ * #KIND = ATAN2,HYPOT,POW,FMOD,COPYSIGN#
  */
 #ifdef @kind@@c@
 #undef @kind@@c@
@@ -412,32 +412,6 @@ NPY_INPLACE @type@ npy_@kind@@c@(@type@ x, @type@ y)
 #endif
 /**end repeat1**/
 
-/**begin repeat1
- * #kind = fmod#
- * #KIND = FMOD#
- */
-#ifdef @kind@@c@
-#undef @kind@@c@
-#endif
-#ifndef HAVE_MODF@C@
-NPY_INPLACE @type@
-npy_@kind@@c@(@type@ x, @type@ y)
-{
-    int are_inputs_inf = (npy_isinf(x) && npy_isinf(y));
-    /* force set invalid flag, doesnt raise by default on gcc < 8 */
-    if (npy_isnan(x) || npy_isnan(y)) {
-        npy_set_floatstatus_invalid();
-    }
-    if (are_inputs_inf || !y) {
-        if (!npy_isnan(x)) {
-            npy_set_floatstatus_invalid();
-        }
-    }
-    return (@type@) npy_@kind@((double)x, (double) y);
-}
-#endif
-/**end repeat1**/
-
 #ifdef modf@c@
 #undef modf@c@
 #endif
@@ -499,8 +473,8 @@ NPY_INPLACE @type@ npy_@kind@@c@(@type@ x)
 /**end repeat1**/
 
 /**begin repeat1
- * #kind = atan2,hypot,pow,copysign#
- * #KIND = ATAN2,HYPOT,POW,COPYSIGN#
+ * #kind = atan2,hypot,pow,fmod,copysign#
+ * #KIND = ATAN2,HYPOT,POW,FMOD,COPYSIGN#
  */
 #ifdef HAVE_@KIND@@C@
 NPY_INPLACE @type@ npy_@kind@@c@(@type@ x, @type@ y)
@@ -510,29 +484,6 @@ NPY_INPLACE @type@ npy_@kind@@c@(@type@ x, @type@ y)
 #endif
 /**end repeat1**/
 
-/**begin repeat1
- * #kind = fmod#
- * #KIND = FMOD#
- */
-#ifdef HAVE_FMOD@C@
-NPY_INPLACE @type@
-npy_@kind@@c@(@type@ x, @type@ y)
-{
-    int are_inputs_inf = (npy_isinf(x) && npy_isinf(y));
-    /* force set invalid flag, doesnt raise by default on gcc < 8 */
-    if (npy_isnan(x) || npy_isnan(y)) {
-        npy_set_floatstatus_invalid();
-    }
-    if (are_inputs_inf || !y) {
-        if (!npy_isnan(x)) {
-            npy_set_floatstatus_invalid();
-        }
-    }
-    return @kind@@c@(x, y);
-}
-#endif
-/**end repeat1**/
-
 #ifdef HAVE_MODF@C@
 NPY_INPLACE @type@ npy_modf@c@(@type@ x, @type@ *iptr)
 {
@@ -682,8 +633,14 @@ npy_remainder@c@(@type@ a, @type@ b)
 {
     @type@ mod;
     if (NPY_UNLIKELY(!b)) {
+        /*
+         * in2 == 0 (and not NaN): normal fmod will give the correct
+         * result (always NaN). `divmod` may set additional FPE for the
+         * division by zero creating an inf.
+         */
         mod = npy_fmod@c@(a, b);
-    } else {
+    }
+    else {
         npy_divmod@c@(a, b, &mod);
     }
     return mod;
@@ -693,13 +650,14 @@ NPY_INPLACE @type@
 npy_floor_divide@c@(@type@ a, @type@ b) {
     @type@ div, mod;
     if (NPY_UNLIKELY(!b)) {
+        /*
+         * in2 == 0 (and not NaN): normal division will give the correct
+         * result (Inf or NaN). `divmod` may set additional FPE for the modulo
+         * evaluating to NaN.
+         */
         div = a / b;
-        if (!a || npy_isnan(a)) {
-            npy_set_floatstatus_invalid();
-        } else {
-            npy_set_floatstatus_divbyzero();
-        }
-    } else {
+    }
+    else {
         div = npy_divmod@c@(a, b, &mod);
     }
     return div;
@@ -715,19 +673,11 @@ npy_divmod@c@(@type@ a, @type@ b, @type@ *modulus)
 {
     @type@ div, mod, floordiv;
 
-    /* force set invalid flag, doesnt raise by default on gcc < 8 */
-    if (npy_isnan(a) || npy_isnan(b)) {
-        npy_set_floatstatus_invalid();
-    }
     mod = npy_fmod@c@(a, b);
     if (NPY_UNLIKELY(!b)) {
-        div = a / b;
-        if (a && !npy_isnan(a)) {
-            npy_set_floatstatus_divbyzero();
-        }
-        /* If b == 0, return result of fmod. For IEEE is nan */
+        /* b == 0 (not NaN): return result of fmod. For IEEE is nan */
         *modulus = mod;
-        return div;
+        return a / b;
     }
 
     /* a - mod should be very nearly an integer multiple of b */
@@ -735,7 +685,7 @@ npy_divmod@c@(@type@ a, @type@ b, @type@ *modulus)
 
     /* adjust fmod result to conform to Python convention of remainder */
     if (mod) {
-        if ((b < 0) != (mod < 0)) {
+        if (isless(b, 0) != isless(mod, 0)) {
             mod += b;
             div -= 1.0@c@;
         }
@@ -748,7 +698,7 @@ npy_divmod@c@(@type@ a, @type@ b, @type@ *modulus)
     /* snap quotient to nearest integral value */
     if (div) {
         floordiv = npy_floor@c@(div);
-        if (div - floordiv > 0.5@c@)
+        if (isgreater(div - floordiv, 0.5@c@))
             floordiv += 1.0@c@;
     }
     else {
diff --git a/numpy/core/src/umath/scalarmath.c.src b/numpy/core/src/umath/scalarmath.c.src
index 66f97a831..5836545f8 100644
--- a/numpy/core/src/umath/scalarmath.c.src
+++ b/numpy/core/src/umath/scalarmath.c.src
@@ -283,19 +283,13 @@ static void
 
 static void
 @name@_ctype_floor_divide(@type@ a, @type@ b, @type@ *out) {
-    @type@ mod;
-
-    if (!b) {
-        *out = a / b;
-    } else {
-        *out = npy_divmod@c@(a, b, &mod);
-    }
+    *out = npy_floor_divide@c@(a, b);
 }
 
 
 static void
 @name@_ctype_remainder(@type@ a, @type@ b, @type@ *out) {
-    npy_divmod@c@(a, b, out);
+    *out = npy_remainder@c@(a, b);
 }
 
 
diff --git a/numpy/core/tests/test_umath.py b/numpy/core/tests/test_umath.py
index 6fd4b4659..ebd61d199 100644
--- a/numpy/core/tests/test_umath.py
+++ b/numpy/core/tests/test_umath.py
@@ -458,10 +458,15 @@ class TestDivision:
         # divide by zero error check
         with np.errstate(divide='raise', invalid='ignore'):
             assert_raises(FloatingPointError, np.floor_divide, fone, fzer)
-        with np.errstate(invalid='raise'):
-            assert_raises(FloatingPointError, np.floor_divide, fnan, fone)
-            assert_raises(FloatingPointError, np.floor_divide, fone, fnan)
-            assert_raises(FloatingPointError, np.floor_divide, fnan, fzer)
+        with np.errstate(divide='ignore', invalid='raise'):
+            np.floor_divide(fone, fzer)
+
+        # The following already contain a NaN and should not warn
+        with np.errstate(all='raise'):
+            np.floor_divide(fnan, fone)
+            np.floor_divide(fone, fnan)
+            np.floor_divide(fnan, fzer)
+            np.floor_divide(fzer, fnan)
 
     @pytest.mark.parametrize('dtype', np.typecodes['Float'])
     def test_floor_division_corner_cases(self, dtype):
@@ -558,6 +563,9 @@ class TestRemainder:
                     else:
                         assert_(b > rem >= 0, msg)
 
+    @pytest.mark.xfail(sys.platform.startswith("darwin"),
+            reason="MacOS seems to not give the correct 'invalid' warning for "
+                   "`fmod`.  Hopefully, others always do.")
     @pytest.mark.parametrize('dtype', np.typecodes['Float'])
     def test_float_divmod_errors(self, dtype):
         # Check valid errors raised for divmod and remainder
@@ -578,8 +586,12 @@ class TestRemainder:
         with np.errstate(divide='ignore', invalid='raise'):
             assert_raises(FloatingPointError, np.divmod, finf, fzero)
         with np.errstate(divide='raise', invalid='ignore'):
-            assert_raises(FloatingPointError, np.divmod, finf, fzero)
+            # inf / 0 does not set any flags, only the modulo creates a NaN
+            np.divmod(finf, fzero)
 
+    @pytest.mark.xfail(sys.platform.startswith("darwin"),
+           reason="MacOS seems to not give the correct 'invalid' warning for "
+                  "`fmod`.  Hopefully, others always do.")
     @pytest.mark.parametrize('dtype', np.typecodes['Float'])
     @pytest.mark.parametrize('fn', [np.fmod, np.remainder])
     def test_float_remainder_errors(self, dtype, fn):
@@ -587,11 +599,16 @@ class TestRemainder:
         fone = np.array(1.0, dtype=dtype)
         finf = np.array(np.inf, dtype=dtype)
         fnan = np.array(np.nan, dtype=dtype)
-        with np.errstate(invalid='raise'):
-            assert_raises(FloatingPointError, fn, fone, fzero)
-            assert_raises(FloatingPointError, fn, fnan, fzero)
-            assert_raises(FloatingPointError, fn, fone, fnan)
-            assert_raises(FloatingPointError, fn, fnan, fone)
+
+        # The following already contain a NaN and should not warn.
+        with np.errstate(all='raise'):
+            with pytest.raises(FloatingPointError,
+                    match="invalid value"):
+                fn(fone, fzero)
+            fn(fnan, fzero)
+            fn(fzero, fnan)
+            fn(fone, fnan)
+            fn(fnan, fone)
 
     def test_float_remainder_overflow(self):
         a = np.finfo(np.float64).tiny