support alt-enter for inserting newline when typing commit message within the app

vendor/github.com/jesseduffield/gocui/edit.go

@@ -5,6 +5,8 @@
 package gocui
 
 import (
+	"unicode"
+
 	"github.com/go-errors/errors"
 
 	"github.com/mattn/go-runewidth"
@@ -53,12 +55,8 @@ func simpleEditor(v *View, key Key, ch rune, mod Modifier) bool {
 		v.MoveCursor(-1, 0, false)
 	case key == KeyArrowRight:
 		v.MoveCursor(1, 0, false)
-	case key == KeyTab:
+	case key == KeyEnter:
 		v.EditNewLine()
-	case key == KeySpace:
-		v.EditWrite(' ')
-	case key == KeyInsert:
-		v.Overwrite = !v.Overwrite
 	case key == KeyCtrlU:
 		v.EditDeleteToStartOfLine()
 	case key == KeyCtrlA:
@@ -66,12 +64,12 @@ func simpleEditor(v *View, key Key, ch rune, mod Modifier) bool {
 	case key == KeyCtrlE:
 		v.EditGotoToEndOfLine()
 		matched = true
+
+	// TODO: see if we need all three of these conditions: maybe the final one is sufficient
+	case ch != 0 && mod == 0 && unicode.IsPrint(ch):
+		v.EditWrite(ch)
 	default:
-		if ch != 0 && mod == 0 {
-			v.EditWrite(ch)
-		} else {
-			matched = false
-		}
+		matched = false
 	}
 
 	return matched

vendor/github.com/jesseduffield/gocui/keybinding.go

@@ -297,7 +297,8 @@ const (
 	// In tcell, these are not keys per se. But in gocui we have them
 	// mapped to the keys so we have to use placeholder keys.
 
-	MouseLeft         = Key(tcell.KeyF63) // arbitrary assignments
+	KeyAltEnter       = Key(tcell.KeyF64) // arbitrary assignments
+	MouseLeft         = Key(tcell.KeyF63)
 	MouseRight        = Key(tcell.KeyF62)
 	MouseMiddle       = Key(tcell.KeyF61)
 	MouseRelease      = Key(tcell.KeyF60)

vendor/github.com/jesseduffield/gocui/tcell_driver.go

@@ -151,7 +151,14 @@ func pollEvent() GocuiEvent {
 			// - shift - will be translated to the final code of rune
 			// - ctrl  - is translated in the key
 			mod = 0
+		} else if mod == tcell.ModAlt && k == tcell.KeyEnter {
+			// for the sake of convenience I'm having a KeyAltEnter key. I will likely
+			// regret this laziness in the future. We're arbitrarily mapping that to tcell's
+			// KeyF64.
+			mod = 0
+			k = tcell.KeyF64
 		}
+
 		return GocuiEvent{
 			Type: eventKey,
 			Key:  Key(k),