Only avoid the blank line at end of view if view is not editable

For editable views it is important to actually show the blank line so that we
can put the cursor there for typing.

This fixes problems with adding blank lines at the end of longer commit
messages.

pkg/utils/lines.go

@@ -109,8 +109,10 @@ func ScanLinesAndTruncateWhenLongerThanBuffer(maxBufferSize int) func(data []byt
 // - the line indices of the original lines, indexed by the wrapped line indices
 // If wrap is false, the text is returned as is.
 // This code needs to behave the same as `gocui.lineWrap` does.
-func WrapViewLinesToWidth(wrap bool, text string, width int) ([]string, []int, []int) {
-	text = strings.TrimSuffix(text, "\n")
+func WrapViewLinesToWidth(wrap bool, editable bool, text string, width int) ([]string, []int, []int) {
+	if !editable {
+		text = strings.TrimSuffix(text, "\n")
+	}
 	lines := strings.Split(text, "\n")
 	if !wrap {
 		indices := make([]int, len(lines))

pkg/utils/lines_test.go

@@ -170,6 +170,7 @@ func TestWrapViewLinesToWidth(t *testing.T) {
 	tests := []struct {
 		name                         string
 		wrap                         bool
+		editable                     bool
 		text                         string
 		width                        int
 		expectedWrappedLines         []string
@@ -378,10 +379,53 @@ func TestWrapViewLinesToWidth(t *testing.T) {
 			expectedWrappedLinesIndices:  []int{0, 2, 6},
 			expectedOriginalLinesIndices: []int{0, 0, 1, 1, 1, 1, 2, 2},
 		},
+		{
+			name:     "Avoid blank line at end if not editable",
+			wrap:     true,
+			editable: false,
+			text:     "First\nSecond\nThird\n",
+			width:    10,
+			expectedWrappedLines: []string{
+				"First",
+				"Second",
+				"Third",
+			},
+			expectedWrappedLinesIndices:  []int{0, 1, 2},
+			expectedOriginalLinesIndices: []int{0, 1, 2},
+		},
+		{
+			name:     "Avoid blank line at end if not editable",
+			wrap:     true,
+			editable: false,
+			text:     "First\nSecond\nThird\n",
+			width:    10,
+			expectedWrappedLines: []string{
+				"First",
+				"Second",
+				"Third",
+			},
+			expectedWrappedLinesIndices:  []int{0, 1, 2},
+			expectedOriginalLinesIndices: []int{0, 1, 2},
+		},
+		{
+			name:     "Keep blank line at end if editable",
+			wrap:     true,
+			editable: true,
+			text:     "First\nSecond\nThird\n",
+			width:    10,
+			expectedWrappedLines: []string{
+				"First",
+				"Second",
+				"Third",
+				"",
+			},
+			expectedWrappedLinesIndices:  []int{0, 1, 2, 3},
+			expectedOriginalLinesIndices: []int{0, 1, 2, 3},
+		},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {
-			wrappedLines, wrappedLinesIndices, originalLinesIndices := WrapViewLinesToWidth(tt.wrap, tt.text, tt.width)
+			wrappedLines, wrappedLinesIndices, originalLinesIndices := WrapViewLinesToWidth(tt.wrap, tt.editable, tt.text, tt.width)
 			assert.Equal(t, tt.expectedWrappedLines, wrappedLines)
 			if tt.expectedWrappedLinesIndices != nil {
 				assert.Equal(t, tt.expectedWrappedLinesIndices, wrappedLinesIndices)
@@ -394,6 +438,7 @@ func TestWrapViewLinesToWidth(t *testing.T) {
 			view := gocui.NewView("", 0, 0, tt.width+1, 1000, gocui.OutputNormal)
 			assert.Equal(t, tt.width, view.InnerWidth())
 			view.Wrap = tt.wrap
+			view.Editable = tt.editable
 			view.SetContent(tt.text)
 			assert.Equal(t, wrappedLines, view.ViewBufferLines())
 		})