Add an optional argument to AssFile::Commit which indicates that only a single line was changed. Currently used only to cut down on file copies when coalescing.

Originally committed to SVN as r5614.

aegisub/src/ass_file.cpp

@@ -760,12 +760,23 @@ wxString AssFile::GetWildcardList(int mode) {
 	else return "";
 }
 
-int AssFile::Commit(wxString desc, int type, int amendId) {
+int AssFile::Commit(wxString desc, int type, int amendId, AssEntry *single_line) {
 	++commitId;
 	// Allow coalescing only if it's the last change and the file has not been
 	// saved since the last change
 	if (commitId == amendId+1 && RedoStack.empty() && savedCommitId != commitId) {
+		// If only one line changed just modify it instead of copying the file
+		if (single_line) {
+			entryIter this_it = Line.begin(), undo_it = UndoStack.back().Line.begin();
+			while (*this_it != single_line) {
+				++this_it;
+				++undo_it;
+			}
+			**undo_it = *single_line;
+		}
+		else {
 			UndoStack.back() = *this;
+		}
 		AnnounceCommit(type);
 		return commitId;
 	}

aegisub/src/ass_file.h

@@ -197,11 +197,12 @@ public:
 	DEFINE_SIGNAL_ADDERS(FileSave, AddFileSaveListener)
 
 	/// @brief Flag the file as modified and push a copy onto the undo stack
-	/// @param desc     Undo description
-	/// @param type     Type of changes made to the file in this commit
-	/// @param commitId Commit to amend rather than pushing a new commit
+	/// @param desc        Undo description
+	/// @param type        Type of changes made to the file in this commit
+	/// @param commitId    Commit to amend rather than pushing a new commit
+	/// @param single_line Line which was changed, if only one line was
 	/// @return Unique identifier for the new undo group
-	int Commit(wxString desc, int type, int commitId = -1);
+	int Commit(wxString desc, int type, int commitId = -1, AssEntry *single_line = 0);
 	/// @brief Undo the last set of changes to the file
 	void Undo();
 	/// @brief Redo the last undone changes

aegisub/src/audio_timing_dialogue.cpp

@@ -392,7 +392,7 @@ void AudioTimingControllerDialogue::Commit()
 			commit_id = -1; // never coalesce with a manually triggered commit
 		}
 		else
-			commit_id = ass->Commit(_("timing"), AssFile::COMMIT_DIAG_TIME, commit_id);
+			commit_id = context->ass->Commit(_("timing"), AssFile::COMMIT_DIAG_TIME, commit_id, selection_controller->GetActiveLine());
 
 		commit_slot.Unblock();
 		timing_modified = false;

aegisub/src/audio_timing_karaoke.cpp

@@ -226,7 +226,7 @@ void AudioTimingControllerKaraoke::GetMarkers(SampleRange const& range, AudioMar
 void AudioTimingControllerKaraoke::DoCommit() {
 	active_line->Text = kara->GetText();
 	file_changed_slot.Block();
-	commit_id = c->ass->Commit(_("karaoke timing"), AssFile::COMMIT_TEXT, commit_id);
+	commit_id = c->ass->Commit(_("karaoke timing"), AssFile::COMMIT_DIAG_TEXT, commit_id, active_line);
 	file_changed_slot.Unblock();
 }
 

aegisub/src/subs_edit_box.cpp

@@ -485,7 +485,7 @@ void SubsEditBox::SetSelectedRows(setter set, T value, wxString desc, int type,
 
 	for_each(sel.begin(), sel.end(), std::tr1::bind(set, _1, value));
 
-	commitId = c->ass->Commit(desc, type, (amend && desc == lastCommitType) ? commitId : -1);
+	commitId = c->ass->Commit(desc, type, (amend && desc == lastCommitType) ? commitId : -1, sel.size() == 1 ? *sel.begin() : 0);
 	lastCommitType = desc;
 }
 
@@ -518,7 +518,7 @@ void SubsEditBox::CommitTimes(TimeField field) {
 		}
 	}
 
-	timeCommitId[field] = c->ass->Commit(_("modify times"), AssFile::COMMIT_DIAG_TIME, timeCommitId[field]);
+	timeCommitId[field] = c->ass->Commit(_("modify times"), AssFile::COMMIT_DIAG_TIME, timeCommitId[field], sel.size() == 1 ? *sel.begin() : 0);
 }
 
 void SubsEditBox::OnSize(wxSizeEvent &evt) {