From: Nobuyoshi Nakada <nobu@...>
Date: 2008-03-06T10:46:41+09:00
Subject: [ruby-dev:33997] Re: printf "[%08f]\n", 0.0/0.0

なかだです。

At Thu, 6 Mar 2008 01:57:27 +0900,
Tanaka Akira wrote in [ruby-dev:33994]:
> 以下のように、printf で NaN, Inf で 0 padding が起こります。
> 
> % ./ruby -ve 'printf "[%08f]\n", 0.0/0.0'
> ruby 1.9.0 (2008-03-06 revision 15699) [i686-linux]
> [00000NaN]
> % ./ruby -e 'printf "[%08f]\n", 1.0/0.0'
> [00000Inf]
> % ./ruby -e 'printf "[%08f]\n", -1.0/0.0'
> [-0000Inf]

テストも間違っているということでしょうか。


Index: sprintf.c
===================================================================
--- sprintf.c	(revision 15701)
+++ sprintf.c	(working copy)
@@ -767,4 +767,5 @@ rb_str_format(int argc, const VALUE *arg
 		    const char *expr;
 
+		    flags &= ~FZERO;
 		    if  (isnan(fval)) {
 			expr = "NaN";
Index: test/ruby/test_sprintf.rb
===================================================================
--- test/ruby/test_sprintf.rb	(revision 15701)
+++ test/ruby/test_sprintf.rb	(working copy)
@@ -88,7 +88,7 @@ class TestSprintf < Test::Unit::TestCase
     assert_equal("    +NaN", sprintf("%+8f", nan))
 
-    assert_equal("00000NaN", sprintf("%08f", nan))
+    assert_equal("     NaN", sprintf("%08f", nan))
     assert_equal("NaN     ", sprintf("%-08f", nan))
-    assert_equal("+0000NaN", sprintf("%+08f", nan))
+    assert_equal("    +NaN", sprintf("%+08f", nan))
 
     assert_equal("     NaN", sprintf("% 8f", nan))
@@ -96,7 +96,7 @@ class TestSprintf < Test::Unit::TestCase
     assert_equal("    +NaN", sprintf("%+ 8f", nan))
 
-    assert_equal(" 0000NaN", sprintf("% 08f", nan))
+    assert_equal("     NaN", sprintf("% 08f", nan))
     assert_equal(" NaN    ", sprintf("%- 08f", nan))
-    assert_equal("+0000NaN", sprintf("%+ 08f", nan))
+    assert_equal("    +NaN", sprintf("%+ 08f", nan))
   end
 
@@ -111,7 +111,7 @@ class TestSprintf < Test::Unit::TestCase
     assert_equal("    +Inf", sprintf("%+8f", inf))
 
-    assert_equal("00000Inf", sprintf("%08f", inf))
+    assert_equal("     Inf", sprintf("%08f", inf))
     assert_equal("Inf     ", sprintf("%-08f", inf))
-    assert_equal("+0000Inf", sprintf("%+08f", inf))
+    assert_equal("    +Inf", sprintf("%+08f", inf))
 
     assert_equal("     Inf", sprintf("% 8f", inf))
@@ -119,7 +119,7 @@ class TestSprintf < Test::Unit::TestCase
     assert_equal("    +Inf", sprintf("%+ 8f", inf))
 
-    assert_equal(" 0000Inf", sprintf("% 08f", inf))
+    assert_equal("     Inf", sprintf("% 08f", inf))
     assert_equal(" Inf    ", sprintf("%- 08f", inf))
-    assert_equal("+0000Inf", sprintf("%+ 08f", inf))
+    assert_equal("    +Inf", sprintf("%+ 08f", inf))
 
     assert_equal("-Inf", sprintf("%f", -inf))
@@ -131,7 +131,7 @@ class TestSprintf < Test::Unit::TestCase
     assert_equal("    -Inf", sprintf("%+8f", -inf))
 
-    assert_equal("-0000Inf", sprintf("%08f", -inf))
+    assert_equal("    -Inf", sprintf("%08f", -inf))
     assert_equal("-Inf    ", sprintf("%-08f", -inf))
-    assert_equal("-0000Inf", sprintf("%+08f", -inf))
+    assert_equal("    -Inf", sprintf("%+08f", -inf))
 
     assert_equal("    -Inf", sprintf("% 8f", -inf))
@@ -139,7 +139,7 @@ class TestSprintf < Test::Unit::TestCase
     assert_equal("    -Inf", sprintf("%+ 8f", -inf))
 
-    assert_equal("-0000Inf", sprintf("% 08f", -inf))
+    assert_equal("    -Inf", sprintf("% 08f", -inf))
     assert_equal("-Inf    ", sprintf("%- 08f", -inf))
-    assert_equal("-0000Inf", sprintf("%+ 08f", -inf))
+    assert_equal("    -Inf", sprintf("%+ 08f", -inf))
     assert_equal('..f00000000',
       sprintf("%x", -2**32), '[ruby-dev:32351]')


-- 
--- 僕の前にBugはない。
--- 僕の後ろにBugはできる。
    中田 伸悦