Fix signum of NAN and int conversion of specials

Author: rtheunissen

php_decimal.c

@@ -211,6 +211,22 @@ static void php_decimal_integer_overflow()
     zend_throw_exception(spl_ce_OverflowException, "Integer overflow", 0);
 }
 
+/**
+ * Called when NaN or Inf is converted to integer.
+ */
+void php_decimal_integer_from_special_is_not_defined()
+{
+    zend_throw_exception(spl_ce_RuntimeException, "Converting NaN or Inf to integer is not defined", 0);
+}
+
+/**
+ * Called when attempting to query the signum of NaN.
+ */
+void php_decimal_sign_of_nan_is_not_defined()
+{
+    zend_throw_exception(spl_ce_RuntimeException, "Sign of NaN is not defined", 0);
+}
+
 /**
  * Called when __construct is called directly on a decimal object.
  */
@@ -777,8 +793,9 @@ static zend_long php_decimal_to_long(php_decimal_t *obj)
     uint32_t  status = 0;
     zend_long result = 0;
 
-    /* This matches PHP's behaviour. */
+    /* PHP converts to zero but that does not make sense and could hide bugs. */
     if (UNEXPECTED(mpd_isspecial(mpd))) {
+        php_decimal_integer_from_special_is_not_defined();
         return 0;
     }
 
@@ -883,6 +900,16 @@ static zend_string *php_decimal_format(php_decimal_t *obj, zend_long places, zen
 /*                                OPERATIONS                                  */
 /******************************************************************************/
 
+static int php_decimal_signum(const mpd_t *mpd)
+{
+    if (UNEXPECTED(mpd_isnan(mpd))) {
+        php_decimal_sign_of_nan_is_not_defined();
+        return 0;
+    }
+
+    return mpd_iszero(mpd) ? 0 : mpd_arith_sign(mpd);
+}
+
 /**
  * Sets the result of res to op1 + op2, using the precision of res.
  *
@@ -2086,7 +2113,7 @@ PHP_DECIMAL_ARGINFO_END()
 PHP_DECIMAL_METHOD(signum)
 {
     PHP_DECIMAL_PARAMS_PARSE_NONE();
-    RETURN_LONG(mpd_iszero(THIS_MPD()) ? 0 : mpd_arith_sign(THIS_MPD()));
+    RETURN_LONG(php_decimal_signum(THIS_MPD()));
 }
 
 /**

tests/cast.phpt

@@ -50,10 +50,6 @@ $tests = [
     [(int) decimal(PHP_INT_MAX),        PHP_INT_MAX],
     [(int) decimal(PHP_INT_MIN),        PHP_INT_MIN],
 
-    [(int) decimal( NAN),               0],
-    [(int) decimal( INF),               0],
-    [(int) decimal(-INF),               0],
-
     /**
      * FLOAT
      */
@@ -92,23 +88,44 @@ foreach ($tests as $test) {
 try {
     (int) decimal("1E+1000");
 } catch (OverflowException $e) {
-    printf("%s\n", $e->getMessage());
+    printf("A %s\n", $e->getMessage());
 }
 
 try {
     (float) decimal("1E-1000");
 } catch (UnderflowException $e) {
-    printf("%s\n", $e->getMessage());
+    printf("B %s\n", $e->getMessage());
 }
 
 try {
     (float) decimal("-1E-1000");
 } catch (UnderflowException $e) {
-    printf("%s\n", $e->getMessage());
+    printf("C %s\n", $e->getMessage());
+}
+
+try {
+    (int) decimal(NAN);
+} catch (RuntimeException $e) {
+    printf("D %s\n", $e->getMessage());
+}
+
+try {
+    (int) decimal(INF);
+} catch (RuntimeException $e) {
+    printf("E %s\n", $e->getMessage());
+}
+
+try {
+    (int) decimal(-INF);
+} catch (RuntimeException $e) {
+    printf("F %s\n", $e->getMessage());
 }
 
 ?>
 --EXPECT--
-Integer overflow
-Floating point underflow
-Floating point underflow
+A Integer overflow
+B Floating point underflow
+C Floating point underflow
+D Converting NaN or Inf to integer is not defined
+E Converting NaN or Inf to integer is not defined
+F Converting NaN or Inf to integer is not defined

tests/methods/signum.phpt

@@ -23,9 +23,15 @@ var_dump(decimal("1234.5678E-9")->signum());
 var_dump(decimal("-1234.5678E+9")->signum());
 var_dump(decimal("-1234.5678E-9")->signum());
 
-var_dump(decimal( "NAN")->signum());
 var_dump(decimal( "INF")->signum());
 var_dump(decimal("-INF")->signum());
+
+try {
+    decimal("NAN")->signum();
+} catch (RuntimeException $e) {
+    printf("%s\n", $e->getMessage());
+}
+
 ?>
 --EXPECT--
 int(0)
@@ -36,5 +42,5 @@ int(1)
 int(-1)
 int(-1)
 int(1)
-int(1)
 int(-1)
+Sign of NaN is not defined

tests/methods/toInt.phpt

@@ -72,6 +72,9 @@ if ((string) $number !== "2.5") {
 
 ?>
 --EXPECT--
+RuntimeException: Converting NaN or Inf to integer is not defined
+RuntimeException: Converting NaN or Inf to integer is not defined
+RuntimeException: Converting NaN or Inf to integer is not defined
 OverflowException: Integer overflow
 TypeError: Decimal\Decimal::__construct() expected parameter 1 to be a string, integer, or decimal, float given
 TypeError: Decimal\Decimal::__construct() expected parameter 1 to be a string, integer, or decimal, float given