4 files changed, 43 insertions, 5 deletions
diff --git a/pkg/field/blank.go b/pkg/field/blank.go
index 2c30b6e..f1ac8b5 100644
--- a/pkg/field/blank.go
+++ b/pkg/field/blank.go
@@ -86,6 +86,9 @@ func (f *Field) Blank(x, y int) {
 	f.x = f.lines[0].x
 	x2 := f.lines[0].l + f.lines[0].x
 	for i := 1; i < f.ly; i++ {
+		if f.lines[i].l == 0 {
+			continue
+		}
 		if f.x > f.lines[i].x {
 			f.x = f.lines[i].x
 		}
diff --git a/pkg/field/blank_test.go b/pkg/field/blank_test.go
index 260c50b..92e446e 100644
--- a/pkg/field/blank_test.go
+++ b/pkg/field/blank_test.go
@@ -45,13 +45,13 @@ func TestBlankInside(t *testing.T) {
 
 func TestBlankInsideLine(t *testing.T) {
 	input := Field{
-		x:  0,
+		x:  -5,
 		y:  0,
-		lx: 3,
+		lx: 8,
 		ly: 3,
 		lines: []Line{
 			Line{x: 0, l: 3, columns: []int{'@', 'a', 'b'}},
-			Line{x: 0, l: 1, columns: []int{'d'}},
+			Line{x: -5, l: 1, columns: []int{'d'}},
 			Line{x: 0, l: 1, columns: []int{'c'}},
 		},
 	}
@@ -62,7 +62,7 @@ func TestBlankInsideLine(t *testing.T) {
 		ly: 3,
 		lines: []Line{
 			Line{x: 0, l: 3, columns: []int{'@', 'a', 'b'}},
-			Line{columns: []int{}},
+			Line{x: -5, columns: []int{}},
 			Line{x: 0, l: 1, columns: []int{'c'}},
 		},
 	}
@@ -74,7 +74,7 @@ func TestBlankInsideLine(t *testing.T) {
 		inputY   int
 		expected *Field
 	}{
-		{"inside", &input, 0, 1, &expected},
+		{"inside", &input, -5, 1, &expected},
 	}
 	for _, tc := range testCases {
 		t.Run(tc.name, func(t *testing.T) {
diff --git a/pkg/field/set.go b/pkg/field/set.go
index c4cf2a4..2b30652 100644
--- a/pkg/field/set.go
+++ b/pkg/field/set.go
@@ -13,6 +13,13 @@ func (f *Field) Set(x, y, v int) {
 				l.x = x
 				l.l = 1
 				l.columns = append(l.columns, v)
+				if f.x > x {
+					f.lx = f.lx + f.x - x
+					f.x = x
+				}
+				if f.lx < x-f.x+1 {
+					f.lx = x - f.x + 1
+				}
 			} else if x >= l.x {
 				if x < l.x+l.l {
 					// just set the value
diff --git a/pkg/field/set_test.go b/pkg/field/set_test.go
index b66c434..c961c2f 100644
--- a/pkg/field/set_test.go
+++ b/pkg/field/set_test.go
@@ -237,6 +237,13 @@ func TestSetAppendResize(t *testing.T) {
 			Line{x: 0, l: 1, columns: []int{'d'}},
 		},
 	}
+	blank := Field{
+		x: 0, y: -1, lx: 2, ly: 3, lines: []Line{
+			Line{x: 0, l: 1, columns: []int{'u'}},
+			Line{x: 0, l: 2, columns: []int{'0', 'r'}},
+			Line{x: 0, l: 1, columns: []int{'d'}},
+		},
+	}
 	xappend := Field{
 		x: -1, y: -1, lx: 5, ly: 3, lines: []Line{
 			Line{x: 0, l: 1, columns: []int{'u'}},
@@ -287,6 +294,24 @@ func TestSetAppendResize(t *testing.T) {
 			Line{x: 3, l: 1, columns: []int{'n'}},
 		},
 	}
+	xappendyappendEp := Field{
+		x: -5, y: -1, lx: 9, ly: 5, lines: []Line{
+			Line{x: 0, l: 1, columns: []int{'u'}},
+			Line{x: -1, l: 3, columns: []int{'l', '0', 'r'}},
+			Line{x: 0, l: 1, columns: []int{'d'}},
+			Line{x: -5, l: 1, columns: []int{'e'}},
+			Line{x: 3, l: 1, columns: []int{'n'}},
+		},
+	}
+	xappendyappendEa := Field{
+		x: -1, y: -1, lx: 7, ly: 5, lines: []Line{
+			Line{x: 0, l: 1, columns: []int{'u'}},
+			Line{x: -1, l: 3, columns: []int{'l', '0', 'r'}},
+			Line{x: 0, l: 1, columns: []int{'d'}},
+			Line{x: 5, l: 1, columns: []int{'e'}},
+			Line{x: 3, l: 1, columns: []int{'n'}},
+		},
+	}
 	// Test cases
 	testCases := []struct {
 		name     string
@@ -296,12 +321,15 @@ func TestSetAppendResize(t *testing.T) {
 		inputV   int
 		expected Field
 	}{
+		{"blank", base, -1, 0, ' ', blank},
 		{"xappend", base, 3, 1, 'n', xappend},
 		{"xprepend", base, -3, 1, 'n', xprepend},
 		{"xprependyprepend", base, -3, -3, 'n', xprependyprepend},
 		{"xappendyprepend", base, 3, -3, 'n', xappendyprepend},
 		{"xprependyappend", base, -3, 3, 'n', xprependyappend},
 		{"xappendyappend", base, 3, 3, 'n', xappendyappend},
+		{"xappendyappendEp", xappendyappend, -5, 2, 'e', xappendyappendEp},
+		{"xappendyappendEa", xappendyappend, 5, 2, 'e', xappendyappendEa},
 	}
 	for _, tc := range testCases {
 		t.Run(tc.name, func(t *testing.T) {