py: Raise exception if trying to convert inf/nan to int.

py/mpz.c

@@ -711,16 +711,9 @@ typedef uint32_t mp_float_int_t;
         // value == 0 || value < 1
         mpz_init_zero(z);
     } else if (u.p.exp == ((1 << EXP_SZ) - 1)) {
-        // inf or NaN
-#if 0
-        // TODO: this probably isn't the right place to throw an exception
-        if(u.p.frc == 0)
-            nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_OverflowError, "cannot convert float infinity to integer"));
-        else
-            nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError, "cannot convert float NaN to integer"));
-#else
+        // u.p.frc == 0 indicates inf, else NaN
+        // should be handled by caller
         mpz_init_zero(z);
-#endif
     } else {
         const int adj_exp = (int)u.p.exp - ((1 << (EXP_SZ - 1)) - 1);
         if (adj_exp < 0) {

py/objint_mpz.c

@@ -298,9 +298,16 @@ mp_obj_t mp_obj_new_int_from_uint(mp_uint_t value) {
 
 #if MICROPY_PY_BUILTINS_FLOAT
 mp_obj_t mp_obj_new_int_from_float(mp_float_t val) {
-    mp_obj_int_t *o = mp_obj_int_new_mpz();
-    mpz_set_from_float(&o->mpz, val);
-    return o;
+    int cl = fpclassify(val);
+    if (cl == FP_INFINITE) {
+        nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_OverflowError, "can't convert inf to int"));
+    } else if (cl == FP_NAN) {
+        nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError, "can't convert NaN to int"));
+    } else {
+        mp_obj_int_t *o = mp_obj_int_new_mpz();
+        mpz_set_from_float(&o->mpz, val);
+        return o;
+    }
 }
 #endif
 

tests/float/float2int.py

@@ -22,3 +22,15 @@ for i in range(0,23):
         print('fail: 10**%u was %u digits long' % (i, digcnt));
         testpass = False
 print("power of 10 test: %s" % (testpass and 'passed' or 'failed'))
+
+# test inf conversion
+try:
+    int(float('inf'))
+except OverflowError:
+    print("OverflowError")
+
+# test nan conversion
+try:
+    int(float('nan'))
+except ValueError:
+    print("ValueError")