Prune redundant items from SCM data source

For uncommitted items we no longer show folders if items from these folders are already shown.

For untracked items we only show the top-level (untracked) directory and not the items it contains.

Frameworks/OakFileBrowser/src/io/FSSCMDataSource.mm

@@ -5,6 +5,7 @@
 #import <OakAppKit/OakFileIconImage.h>
 #import <io/path.h>
 #import <text/encode.h>
+#import <text/ctype.h>
 #import <oak/oak.h>
 
 static NSImage* SCMFolderIcon ()
@@ -34,6 +35,33 @@ static NSArray* convert (std::vector<std::string> const& paths, std::string cons
 	return [FSDataSource sortArray:res usingOptions:options];
 }
 
+template <typename _Iter>
+_Iter prune_path_parents (_Iter it, _Iter last)
+{
+	_Iter out = it;
+	std::sort(it, last);
+	std::reverse(it, last);
+	for(std::string child = NULL_STR; it != last; child = *it++)
+	{
+		if(child.size() <= it->size() || child.at(it->size()) != '/' || child.find(*it) != 0)
+			*out++ = *it;
+	}
+	return out;
+}
+
+template <typename _Iter>
+_Iter prune_path_children (_Iter it, _Iter last)
+{
+	_Iter out = it;
+	std::sort(it, last);
+	for(std::string parent = NULL_STR; it != last; parent = *it++)
+	{
+		if(it->size() <= parent.size() || it->at(parent.size()) != '/' || it->find(parent) != 0)
+			*out++ = *it;
+	}
+	return out;
+}
+
 @implementation FSSCMDataSource
 + (NSURL*)scmURLWithPath:(NSString*)aPath
 {
@@ -52,6 +80,12 @@ static NSArray* convert (std::vector<std::string> const& paths, std::string cons
 		else	unstagedPaths.push_back(pair->first);
 	}
 
+	unstagedPaths.erase(prune_path_parents(unstagedPaths.begin(), unstagedPaths.end()), unstagedPaths.end());
+	untrackedPaths.erase(prune_path_children(untrackedPaths.begin(), untrackedPaths.end()), untrackedPaths.end());
+
+	std::sort(unstagedPaths.begin(), unstagedPaths.end(), text::less_t());
+	std::sort(untrackedPaths.begin(), untrackedPaths.end(), text::less_t());
+
 	FSItem* unstagedItem  = [FSItem itemWithURL:URLAppend(self.rootItem.url, @".unstaged/")];
 	unstagedItem.icon     = SCMFolderIcon();
 	unstagedItem.name     = @"Uncommitted Changes";