[Boost-commit] svn:boost r85519 - in trunk: boost libs/rational/test

Subject: [Boost-commit] svn:boost r85519 - in trunk: boost libs/rational/test
From: dwalker07_at_[hidden]
Date: 2013-08-29 20:22:01

Author: dlwalker
Date: 2013-08-29 20:22:01 EDT (Thu, 29 Aug 2013)
New Revision: 85519
URL: http://svn.boost.org/trac/boost/changeset/85519

Log:
Started modernizing Boost.Rational I/O (refs #7187)

Text files modified: 
   trunk/boost/rational.hpp                   |    60 ++++++++++++++++++++++++++++------------
   trunk/libs/rational/test/rational_test.cpp |    31 +++++++++++++++++++-                    
   2 files changed, 71 insertions(+), 20 deletions(-)

Modified: trunk/boost/rational.hpp
==============================================================================
--- trunk/boost/rational.hpp	Thu Aug 29 19:05:33 2013	(r85518)
+++ trunk/boost/rational.hpp	2013-08-29 20:22:01 EDT (Thu, 29 Aug 2013)	(r85519)
@@ -61,10 +61,13 @@
 
 #include <boost/config.hpp>      // for BOOST_NO_STDC_NAMESPACE, BOOST_MSVC, etc
 #ifndef BOOST_NO_IOSTREAM
-#include <ios>                   // for std::noskipws
+#include <iomanip>               // for std::setw
+#include <ios>                   // for std::noskipws, streamsize
 #include <istream>               // for std::istream
 #include <ostream>               // for std::ostream
+#include <sstream>               // for std::ostringstream
 #endif
+#include <cstddef>               // for NULL
 #include <stdexcept>             // for std::domain_error
 #include <string>                // for std::string implicit constructor
 #include <boost/operators.hpp>   // for boost::addable etc
@@ -593,21 +596,23 @@
     char c = 0;
     detail::resetter sentry(is);
 
-    is >> n;
-    c = is.get();
-
-    if (c != '/')
-        is.clear(std::istream::badbit);  // old GNU c++ lib has no ios_base
-
-#if !defined(__GNUC__) || (defined(__GNUC__) && (__GNUC__ >= 3)) || defined __SGI_STL_PORT
-    is >> std::noskipws;
-#else
-    is.unsetf(ios::skipws); // compiles, but seems to have no effect.
-#endif
-    is >> d;
-
-    if (is)
-        r.assign(n, d);
+    if ( is >> n )
+    {
+        if ( is.get(c) )
+        {
+            if ( c == '/' )
+            {
+                if ( is >> std::noskipws >> d )
+                    // TODO: check if d is non-zero, fail if not.
+                    // ("assign" will normalize the value otherwise.)
+                    // Or: let it throw on normalization fail, but catch the
+                    // exception and translate it to IOStream error handling.
+                    r.assign( n, d );
+            }
+            else
+                is.setstate( std::ios::failbit );
+        }
+    }
 
     return is;
 }
@@ -616,8 +621,27 @@
 template <typename IntType>
 std::ostream& operator<< (std::ostream& os, const rational<IntType>& r)
 {
-    os << r.numerator() << '/' << r.denominator();
-    return os;
+    using namespace std;
+
+    // The slash directly preceeds the denominator, which has no prefixes.
+    ostringstream  ss;
+
+    ss.copyfmt( os );
+    ss.tie( NULL );
+    ss.exceptions( ios::goodbit );
+    ss.width( 0 );
+    ss << noshowpos << noshowbase << '/' << r.denominator();
+
+    // The numerator holds the showpos, internal, and showbase flags.
+    string const   tail = ss.str();
+    streamsize const  w = os.width() - static_cast<streamsize>( tail.size() );
+
+    ss.clear();
+    ss.str( "" );
+    ss.flags( os.flags() );
+    ss << setw( w < 0 || (os.flags() & ios::adjustfield) != ios::internal ? 0 :
+     w ) << r.numerator();
+    return os << ss.str() + tail;
 }
 #endif  // BOOST_NO_IOSTREAM
 

Modified: trunk/libs/rational/test/rational_test.cpp
==============================================================================
--- trunk/libs/rational/test/rational_test.cpp	Thu Aug 29 19:05:33 2013	(r85518)
+++ trunk/libs/rational/test/rational_test.cpp	2013-08-29 20:22:01 EDT (Thu, 29 Aug 2013)	(r85519)
@@ -47,6 +47,8 @@
 #include <boost/test/unit_test.hpp>
 
 #include <climits>
+#include <iomanip>
+#include <ios>
 #include <iostream>
 #include <istream>
 #include <ostream>
@@ -810,10 +812,34 @@
 // Output test
 BOOST_AUTO_TEST_CASE_TEMPLATE( rational_output_test, T, all_signed_test_types )
 {
-    std::ostringstream  oss;
+    using namespace std;
+    typedef boost::rational<T>  rational_type;
+
+    // Basic test
+    ostringstream  oss;
 
-    oss << boost::rational<T>( 44, 14 );
+    oss << rational_type( 44, 14 );
     BOOST_CHECK_EQUAL( oss.str(), "22/7" );
+
+    // Width
+    oss.clear(); oss.str( "" );
+    oss << setw( 5 ) << setfill('*') << rational_type( 1, 2 ) << 'r';
+    BOOST_CHECK_EQUAL( oss.str(), "**1/2r" );  // not "****1/2r"
+
+    // Positive-sign
+    oss.clear(); oss.str( "" );
+    oss << showpos << rational_type( 2, 3 ) << noshowpos;
+    BOOST_CHECK_EQUAL( oss.str(), "+2/3" );  // not "+2/+3"
+
+    // Internal padding
+    oss.clear(); oss.str( "" );
+    oss << setw( 8 ) << internal << rational_type( 36, -15 ) << right << 'r';
+    BOOST_CHECK_EQUAL( oss.str(), "-***12/5r" );  // not "-*****12/5r"
+
+    // Showbase prefix
+    oss.clear(); oss.str( "" );
+    oss << showbase << hex << rational_type( 34, 987 ) << noshowbase << dec;
+    BOOST_CHECK_EQUAL( oss.str(), "0x22/3db" );  // not "0x22/0x3db"
 }
 
 // Input test, failing
@@ -825,6 +851,7 @@
 
     iss >> r;
     BOOST_CHECK( !iss );
+    BOOST_CHECK( !iss.bad() );
 
     iss.clear();
     iss.str( "42" );