add string view substr function

bst789 · May 8, 2016 · 1ee49cc · 1ee49cc
1 parent 8916e7d
commit 1ee49cc
Show file tree

Hide file tree

Showing 3 changed files with 23 additions and 0 deletions.
diff --git a/shared/qcommon/safe/string.cpp b/shared/qcommon/safe/string.cpp
@@ -39,6 +39,17 @@ namespace Q
 		return Ordering::LT;
 	}
 
+	gsl::cstring_view substr( const gsl::cstring_view& lhs, const std::string::size_type pos, const std::string::size_type count )
+	{
+		if( pos > lhs.size() )
+		{
+			throw std::out_of_range( "Q::substr called with out-of-bounds pos parameter!" );
+		}
+		auto start = lhs.begin() + pos;
+		auto end = count == std::string::npos ? lhs.end() : std::min( start + count, lhs.end() );
+		return{ start, end };
+	}
+
 	int svtoi( const gsl::cstring_view& view )
 	{
 		int result = 0;

diff --git a/shared/qcommon/safe/string.h b/shared/qcommon/safe/string.h
@@ -6,6 +6,7 @@
 
 #include <cassert>
 #include <iostream>
+#include <string>
 
 namespace Q
 {
@@ -25,6 +26,8 @@ namespace Q
 		}
 	};
 
+	gsl::cstring_view substr( const gsl::cstring_view& lhs, const std::string::size_type pos = 0, const std::string::size_type count = std::string::npos );
+
 	int svtoi( const gsl::cstring_view& view );
 	float svtof( const gsl::cstring_view& view );
 }

diff --git a/tests/safe/string.cpp b/tests/safe/string.cpp
@@ -35,6 +35,15 @@ BOOST_AUTO_TEST_CASE( stricmp )
 	BOOST_CHECK_EQUAL( Q::stricmp( CSTRING_VIEW( "a" ), CSTRING_VIEW( "" ) ), Q::Ordering::GT );
 }
 
+BOOST_AUTO_TEST_CASE( substr )
+{
+	BOOST_CHECK_EQUAL( Q::substr( CSTRING_VIEW( "Hello World" ), 6 ), CSTRING_VIEW( "World" ) );
+	BOOST_CHECK_EQUAL( Q::substr( CSTRING_VIEW( "Hello World" ), 6, 100 ), CSTRING_VIEW( "World" ) );
+	BOOST_CHECK_EQUAL( Q::substr( CSTRING_VIEW( "Hello World" ), 0, 5 ), CSTRING_VIEW( "Hello" ) );
+	BOOST_CHECK_EQUAL( Q::substr( CSTRING_VIEW( "Hello my World!" ), 6, 2 ), CSTRING_VIEW( "my" ) );
+	BOOST_CHECK_THROW( Q::substr( CSTRING_VIEW( "Hello" ), 20 ), std::out_of_range );
+}
+
 BOOST_AUTO_TEST_CASE( svtoi )
 {
 	BOOST_CHECK_EQUAL( Q::svtoi( CSTRING_VIEW( "" ) ), 0 );