py: Fix build error when float disabled; add test for divmod.

py/builtin.c

@@ -247,14 +247,16 @@ STATIC mp_obj_t mp_builtin_divmod(mp_obj_t o1_in, mp_obj_t o2_in) {
         mp_int_t i1 = MP_OBJ_SMALL_INT_VALUE(o1_in);
         mp_int_t i2 = MP_OBJ_SMALL_INT_VALUE(o2_in);
         if (i2 == 0) {
+            #if MICROPY_PY_BUILTINS_FLOAT
             zero_division_error:
+            #endif
             nlr_raise(mp_obj_new_exception_msg(&mp_type_ZeroDivisionError, "division by zero"));
         }
         mp_obj_t args[2];
         args[0] = MP_OBJ_NEW_SMALL_INT(i1 / i2);
         args[1] = MP_OBJ_NEW_SMALL_INT(i1 % i2);
         return mp_obj_new_tuple(2, args);
-#if MICROPY_PY_BUILTINS_FLOAT
+    #if MICROPY_PY_BUILTINS_FLOAT
     } else if (MP_OBJ_IS_TYPE(o1_in, &mp_type_float) || MP_OBJ_IS_TYPE(o2_in, &mp_type_float)) {
         mp_float_t f1 = mp_obj_get_float(o1_in);
         mp_float_t f2 = mp_obj_get_float(o2_in);
@@ -267,7 +269,7 @@ STATIC mp_obj_t mp_builtin_divmod(mp_obj_t o1_in, mp_obj_t o2_in) {
             mp_obj_new_float(f2),
         };
         return mp_obj_new_tuple(2, tuple);
-#endif
+    #endif
     } else {
         nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_TypeError, "unsupported operand type(s) for divmod(): '%s' and '%s'", mp_obj_get_type_str(o1_in), mp_obj_get_type_str(o2_in)));
     }

tests/float/float_divmod.py

@@ -0,0 +1,25 @@
+# test floating point floor divide and modulus
+# it has some tricky corner cases
+
+def test(x, y):
+    div, mod = divmod(x, y)
+    print('%.8f %.8f %.8f %.8f' % (x // y, x % y, div, mod))
+    print(div == x // y, mod == x % y, abs(div * y + mod - x) < 1e-15)
+
+test(1.23456, 0.7)
+test(-1.23456, 0.7)
+test(1.23456, -0.7)
+test(-1.23456, -0.7)
+
+a = 1.23456
+b = 0.7
+test(a, b)
+test(a, -b)
+test(-a, b)
+test(-a, -b)
+
+for i in range(25):
+    x = (i - 12.5) / 6
+    for j in range(25):
+        y = (j - 12.5) / 6
+        test(x, y)

tests/float/float_divmod_relaxed.py

@@ -0,0 +1,27 @@
+# test floating point floor divide and modulus
+# it has some tricky corner cases
+
+# pyboard has 32-bit floating point and gives different (but still
+# correct) answers for certain combinations of divmod arguments.
+
+def test(x, y):
+    div, mod = divmod(x, y)
+    print(div == x // y, mod == x % y, abs(div * y + mod - x) < 1e-6)
+
+test(1.23456, 0.7)
+test(-1.23456, 0.7)
+test(1.23456, -0.7)
+test(-1.23456, -0.7)
+
+a = 1.23456
+b = 0.7
+test(a, b)
+test(a, -b)
+test(-a, b)
+test(-a, -b)
+
+for i in range(25):
+    x = (i - 12.5) / 6
+    for j in range(25):
+        y = (j - 12.5) / 6
+        test(x, y)