add float division by zero

src/public/py_number.c

@@ -70,6 +70,7 @@ static bool int__truediv__(int argc, py_Ref argv) {
     py_i64 lhs = py_toint(&argv[0]);
     py_f64 rhs;
     if(try_castfloat(&argv[1], &rhs)) {
+        if(rhs == 0.0) return ZeroDivisionError("float division by zero");
         py_newfloat(py_retval(), lhs / rhs);
     } else {
         py_newnotimplemented(py_retval());
@@ -82,6 +83,7 @@ static bool float__truediv__(int argc, py_Ref argv) {
     py_f64 lhs = py_tofloat(&argv[0]);
     py_f64 rhs;
     if(try_castfloat(&argv[1], &rhs)) {
+        if(rhs == 0.0) return ZeroDivisionError("float division by zero");
         py_newfloat(py_retval(), lhs / rhs);
     } else {
         py_newnotimplemented(py_retval());

tests/02_float.py

@@ -54,8 +54,19 @@ assert eq(float("123.456"), 123.456)
 
 
 inf = float("inf")
-assert 1/0 == inf
-assert -1/0 == -inf
+
+try:
+    assert 1/0 == inf
+    exit(1)
+except ZeroDivisionError:
+    pass
+
+try:
+    assert -1/0 == -inf
+    exit(1)
+except ZeroDivisionError:
+    pass
+
 assert 1/inf == 0
 assert -1/inf == 0