* ext/bigdecimal/bigdecimal.c (VpCtoV): 1E1000...000 is interpreted as

  Infinity.  [ruby-dev:36159]

* ext/bigdecimal/bigdecimal.c (VpPower): Infinity ** 1 returns
  Infinity instead of NaN.  [ruby-dev:36159]

* test/bigdecimal/test_bigdecimal.rb: add tests for above.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@19419 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

3 files changed, 47 insertions, 5 deletions

diff --git a/ChangeLog b/ChangeLog
index da07f5688a..1cf32b0bcd 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,13 @@
+Thu Sep 18 22:35:03 2008  Yusuke Endoh  <mame@tsg.ne.jp>
+
+	* ext/bigdecimal/bigdecimal.c (VpCtoV): 1E1000...000 is interpreted as
+	  Infinity.  [ruby-dev:36159]
+
+	* ext/bigdecimal/bigdecimal.c (VpPower): Infinity ** 1 returns
+	  Infinity instead of NaN.  [ruby-dev:36159]
+
+	* test/bigdecimal/test_bigdecimal.rb: add tests for above.
+
 Thu Sep 18 21:57:32 2008  Yukihiro Matsumoto  <matz@ruby-lang.org>
 
 	* string.c (rb_str_comparable): make ascii8bit string to be
diff --git a/ext/bigdecimal/bigdecimal.c b/ext/bigdecimal/bigdecimal.c
index 754c319991..3051143b07 100644
--- a/ext/bigdecimal/bigdecimal.c
+++ b/ext/bigdecimal/bigdecimal.c
@@ -3944,7 +3944,12 @@ VpCtoV(Real *a, const char *int_chr, U_LONG ni, const char *frac, U_LONG nf, con
             es = e*((S_INT)BASE_FIG);
             e = e * 10 + exp_chr[i] - '0';
             if(es>e*((S_INT)BASE_FIG)) {
-                return VpException(VP_EXCEPTION_INFINITY,"exponent overflow",0);
+                VpException(VP_EXCEPTION_INFINITY,"exponent overflow",0);
+                sign = 1;
+                if(int_chr[0] == '-') sign = -1;
+                if(signe > 0) VpSetInf(a, sign);
+                else VpSetZero(a, sign);
+                return 1;
             }
             ++i;
         }
@@ -4633,8 +4638,20 @@ VpPower(Real *y, Real *x, S_INT n)
         }
         goto Exit;
     }
-    if(!VpIsDef(x)) {
-        VpSetNaN(y); /* Not sure !!! */
+    if(VpIsNaN(x)) {
+        VpSetNaN(y);
+        goto Exit;
+    }
+    if(VpIsInf(x)) {
+        if(n==0) {
+            VpSetOne(y);
+            goto Exit;
+        }
+        if(n>0) {
+            VpSetInf(y, (n%2==0 || VpIsPosInf(x)) ? 1 : -1);
+            goto Exit;
+        }
+        VpSetZero(y, (n%2==0 || VpIsPosInf(x)) ? 1 : -1);
         goto Exit;
     }
 
diff --git a/test/bigdecimal/test_bigdecimal.rb b/test/bigdecimal/test_bigdecimal.rb
index c3899033e3..e9d1d0bdb6 100644
--- a/test/bigdecimal/test_bigdecimal.rb
+++ b/test/bigdecimal/test_bigdecimal.rb
@@ -595,7 +595,18 @@ class TestBigDecimal < Test::Unit::TestCase
     assert_equal(BigDecimal.new("-Infinity"), BigDecimal.new("-0") ** -1)
     BigDecimal.mode(BigDecimal::EXCEPTION_NaN, false)
     assert_equal(true, (BigDecimal.new("NaN") ** 1).nan?)
-    assert_equal(true, (BigDecimal.new("Infinity") ** 1).nan?) # OK?
+
+    assert_equal(BigDecimal::SIGN_POSITIVE_INFINITE, (BigDecimal.new("Infinity") ** 2).sign)
+    assert_equal(BigDecimal::SIGN_POSITIVE_INFINITE, (BigDecimal.new("Infinity") ** 1).sign)
+    assert_equal(1, BigDecimal.new("Infinity") ** 0)
+    assert_equal(BigDecimal::SIGN_POSITIVE_ZERO, (BigDecimal.new("Infinity") ** -1).sign)
+    assert_equal(BigDecimal::SIGN_POSITIVE_ZERO, (BigDecimal.new("Infinity") ** -2).sign)
+
+    assert_equal(BigDecimal::SIGN_POSITIVE_INFINITE, (BigDecimal.new("-Infinity") ** 2).sign)
+    assert_equal(BigDecimal::SIGN_NEGATIVE_INFINITE, (BigDecimal.new("-Infinity") ** 1).sign)
+    assert_equal(1, BigDecimal.new("-Infinity") ** 0)
+    assert_equal(BigDecimal::SIGN_NEGATIVE_ZERO, (BigDecimal.new("-Infinity") ** -1).sign)
+    assert_equal(BigDecimal::SIGN_POSITIVE_ZERO, (BigDecimal.new("-Infinity") ** -2).sign)
   end
 
   def test_limit
@@ -676,6 +687,10 @@ class TestBigDecimal < Test::Unit::TestCase
     assert_equal(10, BigDecimal.new("1E+1"))
     assert_equal(1, BigDecimal.new("+1"))
     BigDecimal.mode(BigDecimal::EXCEPTION_OVERFLOW, false)
-    assert_equal(0, BigDecimal.new("1E1" + "0" * 100)) # OK? must it be inf?
+
+    assert_equal(BigDecimal::SIGN_POSITIVE_INFINITE, BigDecimal.new("1E1" + "0" * 10000).sign)
+    assert_equal(BigDecimal::SIGN_NEGATIVE_INFINITE, BigDecimal.new("-1E1" + "0" * 10000).sign)
+    assert_equal(BigDecimal::SIGN_POSITIVE_ZERO, BigDecimal.new("1E-1" + "0" * 10000).sign)
+    assert_equal(BigDecimal::SIGN_NEGATIVE_ZERO, BigDecimal.new("-1E-1" + "0" * 10000).sign)
   end
 end