tui: use full width for zoomed flame bars

2 files changed, 15 insertions, 72 deletions

diff --git a/internal/tui/flamegraph/model.go b/internal/tui/flamegraph/model.go
index 6f5411b..c001e98 100644
--- a/internal/tui/flamegraph/model.go
+++ b/internal/tui/flamegraph/model.go
@@ -468,17 +468,7 @@ func (m *Model) rebuildFrames(animate bool) {
 	} else {
 		root = m.snapshot
 	}
-	layoutWidth := m.width
-	if m.zoomPath != "" {
-		fallbackLineWidth := m.zoomLineWidth
-		if fallbackLineWidth <= 0 {
-			fallbackLineWidth = layoutWidth
-		}
-		if _, gutter, ok := m.zoomLineageGeometry(fallbackLineWidth); ok {
-			layoutWidth = m.width - gutter
-		}
-	}
-	targetFrames := buildTerminalLayoutWithPath(root, layoutWidth, m.height, rootPath)
+	targetFrames := buildTerminalLayoutWithPath(root, m.width, m.height, rootPath)
 	if m.zoomPath != "" {
 		targetFrames = m.withZoomLineage(targetFrames)
 	}
@@ -1151,28 +1141,6 @@ func (m Model) frameIndexAt(x, y int) int {
 	return best
 }
 
-func (m Model) zoomLineageGeometry(fallbackLineWidth int) (lineWidth, gutter int, ok bool) {
-	if m.zoomPath == "" || m.width <= 0 {
-		return 0, 0, false
-	}
-	lineWidth = m.zoomLineWidth
-	if lineWidth <= 0 {
-		lineWidth = fallbackLineWidth
-	}
-	if lineWidth <= 0 {
-		lineWidth = m.width / 4
-	}
-	lineWidth = min(max(lineWidth, 3), max(3, m.width/3))
-	if lineWidth >= m.width-2 {
-		return 0, 0, false
-	}
-	gutter = lineWidth + 1
-	if m.width-gutter < minFlameWidth/2 {
-		return 0, 0, false
-	}
-	return lineWidth, gutter, true
-}
-
 func (m Model) withZoomLineage(frames []tuiFrame) []tuiFrame {
 	if len(frames) == 0 || m.snapshot == nil {
 		return frames
@@ -1182,26 +1150,12 @@ func (m Model) withZoomLineage(frames []tuiFrame) []tuiFrame {
 		return frames
 	}
 
-	fallbackLineWidth := 0
-	if len(frames) > 0 {
-		fallbackLineWidth = frames[0].Width
-	}
-	_, gutter, ok := m.zoomLineageGeometry(fallbackLineWidth)
-	if !ok {
-		return frames
-	}
-	lineageWidth := m.width - gutter
-	if lineageWidth < 1 {
-		return frames
-	}
-
 	rowShift := len(parts) - 1
 	out := make([]tuiFrame, 0, len(frames)+len(parts))
 	for _, frame := range frames {
 		if frame.Path == m.zoomPath {
 			continue
 		}
-		frame.Col += gutter
 		frame.Row += rowShift
 		frame.Depth += rowShift
 		out = append(out, frame)
@@ -1222,9 +1176,9 @@ func (m Model) withZoomLineage(frames []tuiFrame) []tuiFrame {
 		name := parts[depth]
 		out = append(out, tuiFrame{
 			Name:    name,
-			Col:     gutter,
+			Col:     0,
 			Row:     depth,
-			Width:   lineageWidth,
+			Width:   m.width,
 			Total:   total,
 			Percent: percent,
 			Fill:    terminalFrameColor(name),
diff --git a/internal/tui/flamegraph/model_test.go b/internal/tui/flamegraph/model_test.go
index d87ae54..69c1387 100644
--- a/internal/tui/flamegraph/model_test.go
+++ b/internal/tui/flamegraph/model_test.go
@@ -276,12 +276,10 @@ func TestMouseClickOutsideBarsDoesNotChangeSelectionOrZoom(t *testing.T) {
 	}
 }
 
-func TestZoomLineageSpansZoomViewportAndAlignsAtGutter(t *testing.T) {
+func TestZoomLineageSpansFullViewportWidth(t *testing.T) {
 	m := newZoomModel()
 	targetPath := "root" + pathSeparator + "A"
 	targetIdx := mustFrameIndex(t, m.frames, targetPath)
-	selectedWidth := m.frames[targetIdx].Width
-	expectedRailWidth := min(max(selectedWidth, 3), max(3, m.width/3))
 
 	m.selectedIdx = targetIdx
 	m = pressFlameKey(t, m, tea.KeyPressMsg{Code: tea.KeyEnter})
@@ -289,19 +287,14 @@ func TestZoomLineageSpansZoomViewportAndAlignsAtGutter(t *testing.T) {
 
 	rootIdx := mustFrameIndex(t, m.frames, "root")
 	zoomIdx := mustFrameIndex(t, m.frames, targetPath)
-	_, gutter, ok := m.zoomLineageGeometry(expectedRailWidth)
-	if !ok {
-		t.Fatalf("expected lineage geometry to be enabled for zoomed view")
-	}
-	expectedLineageWidth := m.width - gutter
-	if m.frames[rootIdx].Width != expectedLineageWidth {
-		t.Fatalf("expected root lineage width %d, got %d", expectedLineageWidth, m.frames[rootIdx].Width)
+	if m.frames[rootIdx].Width != m.width {
+		t.Fatalf("expected root lineage width %d, got %d", m.width, m.frames[rootIdx].Width)
 	}
-	if m.frames[zoomIdx].Width != expectedLineageWidth {
-		t.Fatalf("expected zoom lineage width %d, got %d", expectedLineageWidth, m.frames[zoomIdx].Width)
+	if m.frames[zoomIdx].Width != m.width {
+		t.Fatalf("expected zoom lineage width %d, got %d", m.width, m.frames[zoomIdx].Width)
 	}
-	if m.frames[rootIdx].Col != gutter || m.frames[zoomIdx].Col != gutter {
-		t.Fatalf("expected lineage rail at column %d, got root=%d zoom=%d", gutter, m.frames[rootIdx].Col, m.frames[zoomIdx].Col)
+	if m.frames[rootIdx].Col != 0 || m.frames[zoomIdx].Col != 0 {
+		t.Fatalf("expected full-width lineage bars at column 0, got root=%d zoom=%d", m.frames[rootIdx].Col, m.frames[zoomIdx].Col)
 	}
 }
 
@@ -318,7 +311,7 @@ func TestZoomLineageKeepsAllFramesWithinViewportWidth(t *testing.T) {
 	}
 }
 
-func TestZoomLineageAlignsWithZoomedSubtreeColumn(t *testing.T) {
+func TestZoomLineageDoesNotShiftZoomedSubtreeHorizontally(t *testing.T) {
 	m := newZoomModel()
 	rootPath := "root" + pathSeparator + "A"
 	childPath := rootPath + pathSeparator + "A1"
@@ -328,15 +321,11 @@ func TestZoomLineageAlignsWithZoomedSubtreeColumn(t *testing.T) {
 
 	rootIdx := mustFrameIndex(t, m.frames, rootPath)
 	childIdx := mustFrameIndex(t, m.frames, childPath)
-	_, gutter, ok := m.zoomLineageGeometry(m.zoomLineWidth)
-	if !ok {
-		t.Fatalf("expected lineage geometry to be enabled")
-	}
-	if got := m.frames[rootIdx].Col; got != gutter {
-		t.Fatalf("expected zoom lineage root column %d, got %d", gutter, got)
+	if got := m.frames[rootIdx].Col; got != 0 {
+		t.Fatalf("expected zoom lineage root column 0, got %d", got)
 	}
-	if got := m.frames[childIdx].Col; got != gutter {
-		t.Fatalf("expected first child column to align at %d, got %d", gutter, got)
+	if got := m.frames[childIdx].Col; got != 0 {
+		t.Fatalf("expected first child column to stay aligned at 0, got %d", got)
 	}
 }