don't let patch manager ever be nil

6 files changed, 48 insertions, 33 deletions

diff --git a/pkg/commands/git.go b/pkg/commands/git.go
index 42c1749af..1448b37cb 100644
--- a/pkg/commands/git.go
+++ b/pkg/commands/git.go
@@ -109,7 +109,7 @@ func NewGitCommand(log *logrus.Entry, osCommand *OSCommand, tr *i18n.Localizer,
 		return nil, err
 	}
 
-	return &GitCommand{
+	gitCommand := &GitCommand{
 		Log:                log,
 		OSCommand:          osCommand,
 		Tr:                 tr,
@@ -120,7 +120,11 @@ func NewGitCommand(log *logrus.Entry, osCommand *OSCommand, tr *i18n.Localizer,
 		getLocalGitConfig:  gitconfig.Local,
 		removeFile:         os.RemoveAll,
 		DotGitDir:          dotGitDir,
-	}, nil
+	}
+
+	gitCommand.PatchManager = NewPatchManager(log, gitCommand.ApplyPatch)
+
+	return gitCommand, nil
 }
 
 func findDotGitDir(stat func(string) (os.FileInfo, error), readFile func(filename string) ([]byte, error)) (string, error) {
diff --git a/pkg/commands/patch_manager.go b/pkg/commands/patch_manager.go
index 1c747c33d..4abf737a0 100644
--- a/pkg/commands/patch_manager.go
+++ b/pkg/commands/patch_manager.go
@@ -25,21 +25,23 @@ type PatchManager struct {
 }
 
 // NewPatchManager returns a new PatchModifier
-func NewPatchManager(log *logrus.Entry, applyPatch applyPatchFunc, commitSha string, diffMap map[string]string) *PatchManager {
-	infoMap := map[string]*fileInfo{}
+func NewPatchManager(log *logrus.Entry, applyPatch applyPatchFunc) *PatchManager {
+	return &PatchManager{
+		Log:        log,
+		ApplyPatch: applyPatch,
+	}
+}
+
+// NewPatchManager returns a new PatchModifier
+func (p *PatchManager) Start(commitSha string, diffMap map[string]string) {
+	p.CommitSha = commitSha
+	p.fileInfoMap = map[string]*fileInfo{}
 	for filename, diff := range diffMap {
-		infoMap[filename] = &fileInfo{
+		p.fileInfoMap[filename] = &fileInfo{
 			mode: UNSELECTED,
 			diff: diff,
 		}
 	}
-
-	return &PatchManager{
-		Log:         log,
-		fileInfoMap: infoMap,
-		CommitSha:   commitSha,
-		ApplyPatch:  applyPatch,
-	}
 }
 
 func (p *PatchManager) AddFile(filename string) {
@@ -200,3 +202,13 @@ func (p *PatchManager) ApplyPatches(reverse bool) error {
 
 	return nil
 }
+
+// clears the patch
+func (p *PatchManager) Reset() {
+	p.CommitSha = ""
+	p.fileInfoMap = map[string]*fileInfo{}
+}
+
+func (p *PatchManager) IsEmpty() bool {
+	return p != nil && p.CommitSha == "" || len(p.fileInfoMap) == 0
+}
diff --git a/pkg/commands/patch_rebases.go b/pkg/commands/patch_rebases.go
index f0dadbc16..19116e071 100644
--- a/pkg/commands/patch_rebases.go
+++ b/pkg/commands/patch_rebases.go
@@ -22,7 +22,7 @@ func (c *GitCommand) DeletePatchesFromCommit(commits []*Commit, commitIndex int,
 	}
 
 	c.onSuccessfulContinue = func() error {
-		c.PatchManager = nil
+		c.PatchManager.Reset()
 		return nil
 	}
 
@@ -50,7 +50,7 @@ func (c *GitCommand) MovePatchToSelectedCommit(commits []*Commit, sourceCommitId
 		}
 
 		c.onSuccessfulContinue = func() error {
-			c.PatchManager = nil
+			c.PatchManager.Reset()
 			return nil
 		}
 
@@ -121,7 +121,7 @@ func (c *GitCommand) MovePatchToSelectedCommit(commits []*Commit, sourceCommitId
 		}
 
 		c.onSuccessfulContinue = func() error {
-			c.PatchManager = nil
+			c.PatchManager.Reset()
 			return nil
 		}
 
@@ -161,7 +161,7 @@ func (c *GitCommand) PullPatchIntoIndex(commits []*Commit, commitIdx int, p *Pat
 			return err
 		}
 
-		c.PatchManager = nil
+		c.PatchManager.Reset()
 		return nil
 	}
 
diff --git a/pkg/gui/commit_files_panel.go b/pkg/gui/commit_files_panel.go
index 0141e25b8..c0cab24cb 100644
--- a/pkg/gui/commit_files_panel.go
+++ b/pkg/gui/commit_files_panel.go
@@ -136,8 +136,8 @@ func (gui *Gui) handleToggleFileForPatch(g *gocui.Gui, v *gocui.View) error {
 	}
 
 	toggleTheFile := func() error {
-		if gui.GitCommand.PatchManager == nil {
-			if err := gui.createPatchManager(); err != nil {
+		if gui.GitCommand.PatchManager.IsEmpty() {
+			if err := gui.startPatchManager(); err != nil {
 				return err
 			}
 		}
@@ -147,9 +147,9 @@ func (gui *Gui) handleToggleFileForPatch(g *gocui.Gui, v *gocui.View) error {
 		return gui.refreshCommitFilesView()
 	}
 
-	if gui.GitCommand.PatchManager != nil && gui.GitCommand.PatchManager.CommitSha != commitFile.Sha {
+	if !gui.GitCommand.PatchManager.IsEmpty() && gui.GitCommand.PatchManager.CommitSha != commitFile.Sha {
 		return gui.createConfirmationPanel(g, v, true, gui.Tr.SLocalize("DiscardPatch"), gui.Tr.SLocalize("DiscardPatchConfirm"), func(g *gocui.Gui, v *gocui.View) error {
-			gui.GitCommand.PatchManager = nil
+			gui.GitCommand.PatchManager.Reset()
 			return toggleTheFile()
 		}, nil)
 	}
@@ -157,7 +157,7 @@ func (gui *Gui) handleToggleFileForPatch(g *gocui.Gui, v *gocui.View) error {
 	return toggleTheFile()
 }
 
-func (gui *Gui) createPatchManager() error {
+func (gui *Gui) startPatchManager() error {
 	diffMap := map[string]string{}
 	for _, commitFile := range gui.State.CommitFiles {
 		commitText, err := gui.GitCommand.ShowCommitFile(commitFile.Sha, commitFile.Name, true)
@@ -172,7 +172,7 @@ func (gui *Gui) createPatchManager() error {
 		return errors.New("No commit selected")
 	}
 
-	gui.GitCommand.PatchManager = commands.NewPatchManager(gui.Log, gui.GitCommand.ApplyPatch, commit.Sha, diffMap)
+	gui.GitCommand.PatchManager.Start(commit.Sha, diffMap)
 	return nil
 }
 
@@ -187,8 +187,8 @@ func (gui *Gui) handleEnterCommitFile(g *gocui.Gui, v *gocui.View) error {
 	}
 
 	enterTheFile := func() error {
-		if gui.GitCommand.PatchManager == nil {
-			if err := gui.createPatchManager(); err != nil {
+		if gui.GitCommand.PatchManager.IsEmpty() {
+			if err := gui.startPatchManager(); err != nil {
 				return err
 			}
 		}
@@ -202,9 +202,9 @@ func (gui *Gui) handleEnterCommitFile(g *gocui.Gui, v *gocui.View) error {
 		return gui.refreshPatchBuildingPanel()
 	}
 
-	if gui.GitCommand.PatchManager != nil && gui.GitCommand.PatchManager.CommitSha != commitFile.Sha {
+	if !gui.GitCommand.PatchManager.IsEmpty() && gui.GitCommand.PatchManager.CommitSha != commitFile.Sha {
 		return gui.createConfirmationPanel(g, v, false, gui.Tr.SLocalize("DiscardPatch"), gui.Tr.SLocalize("DiscardPatchConfirm"), func(g *gocui.Gui, v *gocui.View) error {
-			gui.GitCommand.PatchManager = nil
+			gui.GitCommand.PatchManager.Reset()
 			return enterTheFile()
 		}, nil)
 	}
diff --git a/pkg/gui/patch_building_panel.go b/pkg/gui/patch_building_panel.go
index b32253557..26196f6d1 100644
--- a/pkg/gui/patch_building_panel.go
+++ b/pkg/gui/patch_building_panel.go
@@ -5,7 +5,7 @@ import (
 )
 
 func (gui *Gui) refreshPatchBuildingPanel() error {
-	if gui.GitCommand.PatchManager == nil {
+	if gui.GitCommand.PatchManager.IsEmpty() {
 		return gui.handleEscapePatchBuildingPanel(gui.g, nil)
 	}
 
@@ -91,7 +91,7 @@ func (gui *Gui) handleEscapePatchBuildingPanel(g *gocui.Gui, v *gocui.View) erro
 }
 
 func (gui *Gui) refreshSecondaryPatchPanel() error {
-	if gui.GitCommand.PatchManager != nil {
+	if !gui.GitCommand.PatchManager.IsEmpty() {
 		gui.State.SplitMainPanel = true
 		secondaryView := gui.getSecondaryView()
 		secondaryView.Highlight = true
diff --git a/pkg/gui/patch_options_panel.go b/pkg/gui/patch_options_panel.go
index a966040e2..748f70365 100644
--- a/pkg/gui/patch_options_panel.go
+++ b/pkg/gui/patch_options_panel.go
@@ -17,15 +17,14 @@ func (o *patchMenuOption) GetDisplayStrings(isFocused bool) []string {
 }
 
 func (gui *Gui) handleCreatePatchOptionsMenu(g *gocui.Gui, v *gocui.View) error {
-	m := gui.GitCommand.PatchManager
-	if m == nil {
+	if gui.GitCommand.PatchManager.IsEmpty() {
 		return gui.createErrorPanel(gui.g, gui.Tr.SLocalize("NoPatchError"))
 	}
 
 	options := []*patchMenuOption{
 		{displayName: fmt.Sprintf("remove patch from original commit (%s)", gui.GitCommand.PatchManager.CommitSha), function: gui.handleDeletePatchFromCommit},
 		{displayName: "pull patch out into index", function: gui.handlePullPatchIntoWorkingTree},
-		{displayName: "reset patch", function: gui.handleClearPatch},
+		{displayName: "reset patch", function: gui.handleResetPatch},
 	}
 
 	selectedCommit := gui.getSelectedCommit(gui.g)
@@ -122,7 +121,7 @@ func (gui *Gui) handlePullPatchIntoWorkingTree() error {
 	})
 }
 
-func (gui *Gui) handleClearPatch() error {
-	gui.GitCommand.PatchManager = nil
+func (gui *Gui) handleResetPatch() error {
+	gui.GitCommand.PatchManager.Reset()
 	return gui.refreshCommitFilesView()
 }