Store view regions in undo history

edit.go

@@ -7,6 +7,7 @@ package backend
 import (
 	"fmt"
 
+	"github.com/limetext/backend/render"
 	"github.com/limetext/text"
 )
 
@@ -20,6 +21,9 @@ type (
 		invalid    bool
 		composite  text.CompositeAction
 		savedSel   text.RegionSet
+		finalSel   text.RegionSet
+		savedRegs  render.ViewRegionMap
+		finalRegs  render.ViewRegionMap
 		savedCount int
 		command    string
 		args       Args
@@ -36,9 +40,36 @@ func newEdit(v *View) *Edit {
 	for _, r := range v.Sel().Regions() {
 		ret.savedSel.Add(r)
 	}
+	ret.savedRegs = cloneViewRegionMap(v.regions)
 	return ret
 }
 
+func cloneViewRegionMap(src render.ViewRegionMap) render.ViewRegionMap {
+	if src == nil {
+		return nil
+	}
+	dst := make(render.ViewRegionMap, len(src))
+	for key, regions := range src {
+		dst[key] = *regions.Clone()
+	}
+	return dst
+}
+
+func copyRegionSet(dst *text.RegionSet, src text.RegionSet) {
+	dst.Clear()
+	dst.AddAll(src.Regions())
+}
+
+func (e *Edit) saveFinalRegions() {
+	copyRegionSet(&e.finalSel, *e.v.Sel())
+	e.finalRegs = cloneViewRegionMap(e.v.regions)
+}
+
+func (e *Edit) restoreRegions(sel text.RegionSet, regs render.ViewRegionMap) {
+	copyRegionSet(e.v.Sel(), sel)
+	e.v.regions = cloneViewRegionMap(regs)
+}
+
 // Returns a string describing this Edit object. Should typically not be manually called.
 func (e *Edit) String() string {
 	return fmt.Sprintf("%s: %v, %v, %v", e.command, e.args, e.bypassUndo, e.composite)
@@ -47,13 +78,11 @@ func (e *Edit) String() string {
 // Applies the action of this Edit object. Should typically not be manually called.
 func (e *Edit) Apply() {
 	e.composite.Apply()
+	e.restoreRegions(e.finalSel, e.finalRegs)
 }
 
 // Reverses the application of this Edit object. Should typically not be manually called.
 func (e *Edit) Undo() {
 	e.composite.Undo()
-	e.v.Sel().Clear()
-	for _, r := range e.savedSel.Regions() {
-		e.v.Sel().Add(r)
-	}
+	e.restoreRegions(e.savedSel, e.savedRegs)
 }

undo.go

@@ -121,6 +121,7 @@ func (us *UndoStack) GlueFrom(mark int) {
 	}
 	e.v = us.actions[mark].v
 	e.savedSel.AddAll(us.actions[mark].savedSel.Regions())
+	e.savedRegs = cloneViewRegionMap(us.actions[mark].savedRegs)
 
 	entries := make([]entry, us.position-mark)
 	for i := range entries {
@@ -133,5 +134,6 @@ func (us *UndoStack) GlueFrom(mark int) {
 	us.actions = us.actions[:mark+1]
 	e.args = make(Args)
 	e.args["commands"] = entries
+	e.saveFinalRegions()
 	us.Add(&e)
 }

undo_test.go

@@ -5,6 +5,7 @@
 package backend
 
 import (
+	"reflect"
 	"testing"
 
 	"github.com/limetext/text"
@@ -207,3 +208,87 @@ func TestUndoStackGlueFrom(t *testing.T) {
 		t.Errorf("Expected the UndoStack to only contain 2 things, but it had %d", len(us.actions))
 	}
 }
+
+func TestUndoStackRestoresViewRegions(t *testing.T) {
+	w := GetEditor().NewWindow()
+	defer w.Close()
+
+	v := w.NewFile()
+	defer func() {
+		v.SetScratch(true)
+		v.Close()
+	}()
+
+	e := v.BeginEdit()
+	v.Insert(e, 0, "abcdef")
+	v.EndEdit(e)
+
+	const key = "test"
+	original := []text.Region{{A: 1, B: 3}, {A: 4, B: 6}}
+	v.AddRegions(key, original, "scope", "icon", 0)
+
+	e = v.BeginEdit()
+	v.Erase(e, text.Region{A: 0, B: v.Size()})
+	v.EndEdit(e)
+
+	afterErase := v.GetRegions(key)
+	if reflect.DeepEqual(afterErase, original) {
+		t.Fatalf("expected edit to adjust regions before undo, got unchanged regions %v", afterErase)
+	}
+
+	v.undoStack.Undo(true)
+	if got := v.GetRegions(key); !reflect.DeepEqual(got, original) {
+		t.Fatalf("expected undo to restore regions %v, got %v", original, got)
+	}
+
+	v.undoStack.Redo(true)
+	if got := v.GetRegions(key); !reflect.DeepEqual(got, afterErase) {
+		t.Fatalf("expected redo to restore edited regions %v, got %v", afterErase, got)
+	}
+}
+
+func TestUndoStackGlueFromRestoresViewRegions(t *testing.T) {
+	w := GetEditor().NewWindow()
+	defer w.Close()
+
+	v := w.NewFile()
+	defer func() {
+		v.SetScratch(true)
+		v.Close()
+	}()
+
+	e := v.BeginEdit()
+	v.Insert(e, 0, "abcdef")
+	v.EndEdit(e)
+
+	mark := v.undoStack.Position()
+
+	const key = "test"
+	original := []text.Region{{A: 1, B: 3}, {A: 4, B: 6}}
+	v.AddRegions(key, original, "scope", "icon", 0)
+
+	e = v.BeginEdit()
+	v.Erase(e, text.Region{A: 1, B: 2})
+	v.EndEdit(e)
+
+	e = v.BeginEdit()
+	v.Insert(e, 2, "Z")
+	v.EndEdit(e)
+
+	final := v.GetRegions(key)
+	if reflect.DeepEqual(final, original) {
+		t.Fatalf("expected edits to adjust regions before glue, got unchanged regions %v", final)
+	}
+
+	v.undoStack.GlueFrom(mark)
+
+	v.undoStack.Undo(true)
+	if got := v.GetRegions(key); !reflect.DeepEqual(got, original) {
+		t.Fatalf("expected glued undo to restore regions %v, got %v", original, got)
+	}
+
+	v.undoStack.Redo(true)
+	if got := v.GetRegions(key); !reflect.DeepEqual(got, final) {
+		t.Fatalf("expected glued redo to restore regions %v, got %v", final, got)
+	}
+}

view.go

@@ -431,6 +431,7 @@ func (v *View) EndEdit(edit *Edit) {
 	for j := len(v.editstack) - 1; j >= i; j-- {
 		current_edit := v.editstack[j]
 		current_edit.invalid = true
+		current_edit.saveFinalRegions()
 		sel_same := reflect.DeepEqual(*v.Sel(), current_edit.savedSel)
 		buf_same := v.ChangeCount() == current_edit.savedCount
 		eq := (sel_same && buf_same && current_edit.composite.Len() == 0)