StringView_Partition for One-Off Splits

src/StringView/StringView.c

@@ -133,6 +133,22 @@ StringView StringView_Slice(StringView string, size_t start, size_t end)
 	return slice;
 }
 
+bool StringView_Partition(StringView* left, StringView* right, StringView source, StringView delim)
+{
+	if (source.length == 0) return false;
+
+	size_t offset = StringView_FindStringOffset(source, delim);
+	if (offset != SIZE_MAX) {
+		if (left != NULL)  *left  = StringView_Slice(source, 0, offset);
+		if (right != NULL) *right = StringView_Slice(source, offset + delim.length, source.length);
+	} else {
+		if (left != NULL)  *left  = source;
+		if (right != NULL) *right = STRINGVIEW_NONE;
+	}
+
+	return offset != SIZE_MAX;
+}
+
 bool StringView_NextSplit(StringView* dest, StringView* source, StringView delim)
 {
 	if (source->length == 0) return false;
@@ -149,6 +165,23 @@ bool StringView_NextSplit(StringView* dest, StringView* source, StringView delim
 	return true;
 }
 
+bool StringView_LastSplit(StringView* dest, StringView* source, StringView delim)
+{
+	StringView s = *source;
+	while (s.length != 0 && ! StringView_EndsWith(s, delim)) {
+		s.length -= 1;
+	}
+
+	if (s.length == 0) {
+		return false;
+	} else {
+		*dest = StringView_Slice(*source, s.length, source->length);
+		s.length -= delim.length;
+		*source = s;
+		return true;
+	}
+}
+
 StringView StringView_StripLeft(StringView sv, StringView strip)
 {
 	while (StringView_StartsWith(sv, strip)) {

src/StringView/StringView.h

@@ -46,7 +46,9 @@ size_t StringView_FindStringOffset(StringView haystack, StringView needle);
 StringView StringView_FindString(StringView haystack, StringView needle);
 StringView StringView_Slice(StringView string, size_t start, size_t end); // start and end are offsets
 
+bool StringView_Partition(StringView* left, StringView* right, StringView source, StringView delim);
 bool StringView_NextSplit(StringView* dest, StringView* source, StringView delim);
+bool StringView_LastSplit(StringView* dest, StringView* source, StringView delim);
 
 StringView StringView_StripLeft(StringView sv, StringView strip);
 StringView StringView_StripRight(StringView sv, StringView strip);

tests/StringView.test.c

@@ -29,8 +29,24 @@ void test_split(void)
 	return;
 }
 
+void test_fext(void)
+{
+	const char* filepath = "database.sqlite.old";
+
+	StringView sourceSV = StringView_FromString(filepath);
+	StringView delim   = StringView_FromString(".");
+	StringView split;
+
+	assert(StringView_LastSplit(&split, &sourceSV, delim));
+	assert(StringView_Equal(split, StringView_FromString("old")));
+	assert(StringView_Equal(sourceSV, StringView_FromString("database.sqlite")));
+
+	return;
+}
+
 int main()
 {
 	test_split();
+	test_fext();
 	return 0;
 }