Fix Bug 30240 - std::string: append(first, last) error when aliasing. Add test cases for append/insert/assign/replace while we're at it, and fix a similar bug in insert.

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@280643 91177308-0d34-0410-b5e6-96231b3b80d8

test/std/strings/basic.string/string.modifiers/string_insert/iter_iter_iter.pass.cpp

@@ -169,4 +169,21 @@ int main()
         assert(false);
     }
 #endif
+
+	{ // test inserting into self
+    typedef std::string S;
+	S s_short = "123/";
+	S s_long  = "Lorem ipsum dolor sit amet, consectetur/";
+	
+	s_short.insert(s_short.begin(), s_short.begin(), s_short.end());
+	assert(s_short == "123/123/");
+	s_short.insert(s_short.begin(), s_short.begin(), s_short.end());
+	assert(s_short == "123/123/123/123/");
+	s_short.insert(s_short.begin(), s_short.begin(), s_short.end());
+	assert(s_short == "123/123/123/123/123/123/123/123/");
+	
+	s_long.insert(s_long.begin(), s_long.begin(), s_long.end());
+	assert(s_long == "Lorem ipsum dolor sit amet, consectetur/Lorem ipsum dolor sit amet, consectetur/");
+	}
+
 }

test/std/strings/basic.string/string.modifiers/string_insert/size_pointer.pass.cpp

@@ -210,4 +210,20 @@ int main()
     test(S("abcdefghijklmnopqrst"), 21, "12345678901234567890", S("can't happen"));
     }
 #endif
+
+	{ // test inserting into self
+    typedef std::string S;
+	S s_short = "123/";
+	S s_long  = "Lorem ipsum dolor sit amet, consectetur/";
+	
+	s_short.insert(0, s_short.c_str());
+	assert(s_short == "123/123/");
+	s_short.insert(0, s_short.c_str());
+	assert(s_short == "123/123/123/123/");
+	s_short.insert(0, s_short.c_str());
+	assert(s_short == "123/123/123/123/123/123/123/123/");
+	
+	s_long.insert(0, s_long.c_str());
+	assert(s_long == "Lorem ipsum dolor sit amet, consectetur/Lorem ipsum dolor sit amet, consectetur/");
+	}
 }

test/std/strings/basic.string/string.modifiers/string_insert/size_pointer_size.pass.cpp

@@ -691,4 +691,20 @@ int main()
     test(S("abcdefghijklmnopqrst"), 21, "12345678901234567890", 20, S("can't happen"));
     }
 #endif
+
+	{ // test inserting into self
+    typedef std::string S;
+	S s_short = "123/";
+	S s_long  = "Lorem ipsum dolor sit amet, consectetur/";
+	
+	s_short.insert(0, s_short.data(), s_short.size());
+	assert(s_short == "123/123/");
+	s_short.insert(0, s_short.data(), s_short.size());
+	assert(s_short == "123/123/123/123/");
+	s_short.insert(0, s_short.data(), s_short.size());
+	assert(s_short == "123/123/123/123/123/123/123/123/");
+	
+	s_long.insert(0, s_long.data(), s_long.size());
+	assert(s_long == "Lorem ipsum dolor sit amet, consectetur/Lorem ipsum dolor sit amet, consectetur/");
+	}
 }