Fix wrong rendering with two empty annotations

annot.go

@@ -83,13 +83,12 @@ func Write(w io.Writer, annots ...*Annot) error {
 	for _, a := range annots {
 		if len(a.Lines) == 0 {
 			a.lines = append(a.lines, &line{})
-			break
+			continue
 		}
 		a.lines = make([]*line, len(a.Lines))
 		for i := range a.Lines {
 			a.lines[i] = &line{
-				//             3 for "└─ " or "   " (indentation)
-				length:        3 + utf8.RuneCountInString(a.Lines[i]),
+				length:        utf8.RuneCountInString(a.Lines[i]),
 				leadingSpaces: a.Col,
 			}
 		}
@@ -153,7 +152,8 @@ func checkLineAndSetSpace(row, aLineIdx int, a *Annot, rightAnnots []*Annot) boo
 		return true
 	}
 
-	lineLength := a.lines[aLineIdx].length
+	//            3 for "└─ " or "   " (indentation)
+	lineLength := 3 + a.lines[aLineIdx].length
 
 	remainingSpaces := closestA.Col - a.Col - lineLength
 

annot_test.go

@@ -20,6 +20,20 @@ func TestWrite(t *testing.T) {
 			wantW: `
 ↑
 └─ 
+`,
+			wantErr: false,
+		},
+		{
+			name: "two empty annotations",
+			annots: []*Annot{
+				{Col: 0},
+				{Col: 2},
+			},
+			wantW: `
+↑ ↑
+│ └─ 
+│
+└─ 
 `,
 			wantErr: false,
 		},