fix(tui): preserve rendered indentation in selections

- trim only empty edge rows instead of full selected text
- bound selection paint using unwritten cells so rendered indentation remains copyable

ui-tui/packages/hermes-ink/src/ink/selection.test.ts

@@ -19,6 +19,8 @@ const screenWithText = () => {
   return { screen, styles }
 }
 
+const styledSpace = (styles: StylePool) => styles.intern([{ code: '\x1b[4m', endCode: '\x1b[24m', type: 'ansi' }])
+
 describe('selection whitespace handling', () => {
   it('does not copy whitespace-only selections', () => {
     const { screen } = screenWithText()
@@ -40,6 +42,22 @@ describe('selection whitespace handling', () => {
     expect(getSelectedText(selection, screen)).toBe('hi')
   })
 
+  it('preserves selected indentation when spaces are rendered content', () => {
+    const styles = new StylePool()
+    const screen = createScreen(10, 1, styles, new CharPool(), new HyperlinkPool())
+    const indentStyle = styledSpace(styles)
+    const selection = createSelectionState()
+
+    setCellAt(screen, 0, 0, { char: ' ', hyperlink: undefined, styleId: indentStyle, width: CellWidth.Narrow })
+    setCellAt(screen, 1, 0, { char: ' ', hyperlink: undefined, styleId: indentStyle, width: CellWidth.Narrow })
+    setCellAt(screen, 2, 0, { char: 'x', hyperlink: undefined, styleId: screen.emptyStyleId, width: CellWidth.Narrow })
+
+    startSelection(selection, 0, 0)
+    updateSelection(selection, 9, 0)
+
+    expect(getSelectedText(selection, screen)).toBe('  x')
+  })
+
   it('does not paint selection background on leading/trailing empty cells or empty rows', () => {
     const { screen, styles } = screenWithText()
     const selection = createSelectionState()

ui-tui/packages/hermes-ink/src/ink/selection.ts

@@ -12,7 +12,7 @@
 
 import { clamp } from './layout/geometry.js'
 import type { Screen, StylePool } from './screen.js'
-import { cellAt, cellAtIndex, CellWidth, setCellStyleId } from './screen.js'
+import { cellAt, cellAtIndex, CellWidth, isEmptyCellAt, setCellStyleId } from './screen.js'
 
 type Point = { col: number; row: number }
 
@@ -842,31 +842,41 @@ export function isCellSelected(s: SelectionState, col: number, row: number): boo
   return true
 }
 
-function rowSelectableContentBounds(screen: Screen, row: number): { first: number; last: number } | null {
-  if (row < 0 || row >= screen.height) {
+function selectableCell(screen: Screen, row: number, col: number): boolean {
+  const cell = cellAt(screen, col, row)
+
+  return (
+    screen.noSelect[row * screen.width + col] !== 1 &&
+    !isEmptyCellAt(screen, col, row) &&
+    !!cell &&
+    cell.width !== CellWidth.SpacerTail &&
+    cell.width !== CellWidth.SpacerHead
+  )
+}
+
+function selectionContentBounds(
+  screen: Screen,
+  row: number,
+  start: number,
+  end: number
+): { first: number; last: number } | null {
+  let first = start
+
+  while (first <= end && !selectableCell(screen, row, first)) {
+    first++
+  }
+
+  if (first > end) {
     return null
   }
 
-  const rowOff = row * screen.width
-  let first = -1
-  let last = -1
+  let last = end
 
-  for (let col = 0; col < screen.width; col++) {
-    if (screen.noSelect[rowOff + col] === 1) {
-      continue
+  while (last >= first && !selectableCell(screen, row, last)) {
+    last--
   }
 
-    const cell = cellAt(screen, col, row)
-
-    if (!cell || cell.width === CellWidth.SpacerTail || cell.width === CellWidth.SpacerHead || !cell.char.trim()) {
-      continue
-    }
-
-    first = first === -1 ? col : first
-    last = col
-  }
-
-  return first === -1 ? null : { first, last }
+  return { first, last }
 }
 
 /** Extract text from one screen row. When the next row is a soft-wrap
@@ -917,6 +927,21 @@ function joinRows(lines: string[], text: string, sw: boolean | undefined): void
   }
 }
 
+function trimEmptyEdgeRows(lines: string[]): string[] {
+  let start = 0
+  let end = lines.length
+
+  while (start < end && !lines[start]!.trim()) {
+    start++
+  }
+
+  while (end > start && !lines[end - 1]!.trim()) {
+    end--
+  }
+
+  return lines.slice(start, end)
+}
+
 /**
  * Extract text from the screen buffer within the selection range.
  * Rows are joined with newlines unless the screen's softWrap bitmap
@@ -946,14 +971,16 @@ export function getSelectedText(s: SelectionState, screen: Screen): string {
   for (let row = start.row; row <= end.row; row++) {
     const rowStart = row === start.row ? start.col : 0
     const rowEnd = row === end.row ? end.col : screen.width - 1
-    joinRows(lines, extractRowText(screen, row, rowStart, rowEnd), sw[row]! > 0)
+    const bounds = selectionContentBounds(screen, row, rowStart, rowEnd)
+
+    joinRows(lines, bounds ? extractRowText(screen, row, bounds.first, bounds.last) : '', sw[row]! > 0)
   }
 
   for (let i = 0; i < s.scrolledOffBelow.length; i++) {
     joinRows(lines, s.scrolledOffBelow[i]!, s.scrolledOffBelowSW[i])
   }
 
-  return lines.join('\n').trim()
+  return trimEmptyEdgeRows(lines).join('\n')
 }
 
 /**
@@ -1076,21 +1103,16 @@ export function applySelectionOverlay(screen: Screen, selection: SelectionState,
   const noSelect = screen.noSelect
 
   for (let row = start.row; row <= end.row && row < screen.height; row++) {
-    const bounds = rowSelectableContentBounds(screen, row)
+    const colStart = row === start.row ? start.col : 0
+    const colEnd = row === end.row ? Math.min(end.col, width - 1) : width - 1
+    const bounds = selectionContentBounds(screen, row, colStart, colEnd)
+    const rowOff = row * width
 
     if (!bounds) {
       continue
     }
 
-    const colStart = Math.max(row === start.row ? start.col : 0, bounds.first)
-    const colEnd = Math.min(row === end.row ? end.col : width - 1, bounds.last)
-    const rowOff = row * width
-
-    if (colStart > colEnd) {
-      continue
-    }
-
-    for (let col = colStart; col <= colEnd; col++) {
+    for (let col = bounds.first; col <= bounds.last; col++) {
       const idx = rowOff + col
 
       // Skip noSelect cells — gutters stay visually unchanged so it's