prevent infinite render loop (fixes #184)

Author: wagoodman

Diff for: README.md

@@ -74,14 +74,14 @@ Analyze and image and get a pass/fail result based on the image efficiency and w
 
 **Ubuntu/Debian**
 ```bash
-wget https://github.com/wagoodman/dive/releases/download/v0.7.0/dive_0.7.0_linux_amd64.deb
-sudo apt install ./dive_0.7.0_linux_amd64.deb
+wget https://github.com/wagoodman/dive/releases/download/v0.7.1/dive_0.7.1_linux_amd64.deb
+sudo apt install ./dive_0.7.1_linux_amd64.deb
 ```
 
 **RHEL/Centos**
 ```bash
-curl -OL https://github.com/wagoodman/dive/releases/download/v0.7.0/dive_0.7.0_linux_amd64.rpm
-rpm -i dive_0.7.0_linux_amd64.rpm
+curl -OL https://github.com/wagoodman/dive/releases/download/v0.7.1/dive_0.7.1_linux_amd64.rpm
+rpm -i dive_0.7.1_linux_amd64.rpm
 ```
 
 **Arch Linux**
@@ -100,11 +100,11 @@ The above example assumes [`yay`](https://aur.archlinux.org/packages/yay/) as th
 brew tap wagoodman/dive
 brew install dive
 ```
-or download the latest Darwin build from the [releases page](https://github.com/wagoodman/dive/releases/download/v0.7.0/dive_0.7.0_darwin_amd64.tar.gz).
+or download the latest Darwin build from the [releases page](https://github.com/wagoodman/dive/releases/download/v0.7.1/dive_0.7.1_darwin_amd64.tar.gz).
 
 **Windows**
 
-Download the [latest release](https://github.com/wagoodman/dive/releases/download/v0.7.0/dive_0.7.0_windows_amd64.zip).
+Download the [latest release](https://github.com/wagoodman/dive/releases/download/v0.7.1/dive_0.7.1_windows_amd64.zip).
 
 **Go tools**
 Requires Go version 1.9 or higher.

Diff for: ui/filetree_controller.go

@@ -331,9 +331,12 @@ func filterRegex() *regexp.Regexp {
 }
 
 // onLayoutChange is called by the UI framework to inform the view-model of the new screen dimensions
-func (controller *FileTreeController) onLayoutChange() error {
+func (controller *FileTreeController) onLayoutChange(resized bool) error {
 	controller.Update()
-	return controller.Render()
+	if resized {
+		return controller.Render()
+	}
+	return nil
 }
 
 // Update refreshes the state objects for future rendering.

Diff for: ui/ui.go

@@ -59,6 +59,8 @@ var GlobalKeybindings struct {
 	filterView []keybinding.Key
 }
 
+var lastX, lastY int
+
 // View defines the a renderable terminal screen pane.
 type View interface {
 	Setup(*gocui.View, *gocui.View) error
@@ -187,6 +189,14 @@ func layout(g *gocui.Gui) error {
 	// TODO: this logic should be refactored into an abstraction that takes care of the math for us
 
 	maxX, maxY := g.Size()
+	var resized bool
+	if maxX != lastX {
+		resized = true
+	}
+	if maxY != lastY {
+		resized = true
+	}
+	lastX, lastY = maxX, maxY
 	fileTreeSplitRatio := viper.GetFloat64("filetree.pane-width")
 	if fileTreeSplitRatio >= 1 || fileTreeSplitRatio <= 0 {
 		logrus.Errorf("invalid config value: 'filetree.pane-width' should be 0 < value < 1, given '%v'", fileTreeSplitRatio)
@@ -260,7 +270,7 @@ func layout(g *gocui.Gui) error {
 	if isNewView(viewErr, headerErr) {
 		Controllers.Tree.Setup(view, header)
 	}
-	Controllers.Tree.onLayoutChange()
+	Controllers.Tree.onLayoutChange(resized)
 
 	// Status Bar
 	view, viewErr = g.SetView(Controllers.Status.Name, -1, maxY-statusBarHeight-statusBarIndex, maxX, maxY-(statusBarIndex-1))