# UndoRedo Class

Manages undo/redo stacks for all spreadsheet operations.

# oldData: Preserving Formula ASTs Across Irreversible Transformations

Some structural operations (e.g., removing rows/columns, moving cells) destroy formula information that cannot be reconstructed from the transformation alone. For example, when a row is removed, formulas referencing that row are rewritten to #REF! — an irreversible change.

To support undo of such operations, oldData stores snapshots of formula AST hashes keyed by the LazilyTransformingAstService version at which the irreversible transformation was applied. Each entry maps a version number to an array of [cellAddress, astHash] pairs that can be used to restore the original formula from the parser cache.

# Memory Management

Without cleanup, oldData grows indefinitely as undo entries are evicted but their oldData keys remain. Three mechanisms prevent this:

  1. Eviction cleanup: When undo entries are evicted (due to undoLimit), cleanupOldDataForEntries() deletes their referenced oldData keys (unless still needed by entries on the other stack).
  2. Orphan cleanup: Compaction may force lazy formula evaluation, which writes new oldData entries for already-evicted undo entries. After compaction, cleanupOrphanedOldData() removes any keys not referenced by entries on either stack or the in-progress batch.
  3. Short-circuit: When undoLimit is 0 (undo disabled), storeDataForVersion() returns immediately to avoid storing data that would never be used.

# Constructors

# constructor

+ new UndoRedo(config: Config, operations: Operations): UndoRedo

Defined in src/UndoRedo.ts:505 (opens new window)

Parameters:

Name Type
config Config
operations Operations

Returns: UndoRedo

# Properties

# oldData

• oldData: Map‹number, [SimpleCellAddress, string][]› = new Map()

Defined in src/UndoRedo.ts:501 (opens new window)

# Methods

# beginBatchMode

▸ beginBatchMode(): void

Defined in src/UndoRedo.ts:522 (opens new window)

Returns: void


# cleanupOrphanedOldData

▸ cleanupOrphanedOldData(): void

Defined in src/UndoRedo.ts:880 (opens new window)

Removes oldData entries whose version keys are not referenced by any entry on the undo stack, redo stack, or in-progress batch. Called after compaction forces lazy formula evaluation, which may insert oldData for already-evicted entries.

Returns: void


# clearRedoStack

▸ clearRedoStack(): void

Defined in src/UndoRedo.ts:550 (opens new window)

Clears the redo stack and removes oldData entries no longer referenced by any remaining entry.

Returns: void


# clearUndoStack

▸ clearUndoStack(): void

Defined in src/UndoRedo.ts:556 (opens new window)

Clears the undo stack and removes oldData entries no longer referenced by any remaining entry.

Returns: void


# commitBatchMode

▸ commitBatchMode(): void

Defined in src/UndoRedo.ts:526 (opens new window)

Returns: void


# isRedoStackEmpty

▸ isRedoStackEmpty(): boolean

Defined in src/UndoRedo.ts:565 (opens new window)

Returns: boolean


# isUndoStackEmpty

▸ isUndoStackEmpty(): boolean

Defined in src/UndoRedo.ts:561 (opens new window)

Returns: boolean


# redo

▸ redo(): void

Defined in src/UndoRedo.ts:756 (opens new window)

Returns: void


# redoAddColumns

▸ redoAddColumns(operation: AddColumnsUndoEntry): void

Defined in src/UndoRedo.ts:808 (opens new window)

Parameters:

Name Type
operation AddColumnsUndoEntry

Returns: void


# redoAddNamedExpression

▸ redoAddNamedExpression(operation: AddNamedExpressionUndoEntry): void

Defined in src/UndoRedo.ts:841 (opens new window)

Parameters:

Name Type
operation AddNamedExpressionUndoEntry

Returns: void


# redoAddRows

▸ redoAddRows(operation: AddRowsUndoEntry): void

Defined in src/UndoRedo.ts:804 (opens new window)

Parameters:

Name Type
operation AddRowsUndoEntry

Returns: void


# redoAddSheet

▸ redoAddSheet(operation: AddSheetUndoEntry): void

Defined in src/UndoRedo.ts:816 (opens new window)

Parameters:

Name Type
operation AddSheetUndoEntry

Returns: void


# redoBatch

▸ redoBatch(batchOperation: BatchUndoEntry): void

Defined in src/UndoRedo.ts:768 (opens new window)

Parameters:

Name Type
batchOperation BatchUndoEntry

Returns: void


# redoChangeNamedExpression

▸ redoChangeNamedExpression(operation: ChangeNamedExpressionUndoEntry): void

Defined in src/UndoRedo.ts:849 (opens new window)

Parameters:

Name Type
operation ChangeNamedExpressionUndoEntry

Returns: void


# redoClearSheet

▸ redoClearSheet(operation: ClearSheetUndoEntry): void

Defined in src/UndoRedo.ts:832 (opens new window)

Parameters:

Name Type
operation ClearSheetUndoEntry

Returns: void


# redoMoveCells

▸ redoMoveCells(operation: MoveCellsUndoEntry): void

Defined in src/UndoRedo.ts:778 (opens new window)

Parameters:

Name Type
operation MoveCellsUndoEntry

Returns: void


# redoMoveColumns

▸ redoMoveColumns(operation: MoveColumnsUndoEntry): void

Defined in src/UndoRedo.ts:828 (opens new window)

Parameters:

Name Type
operation MoveColumnsUndoEntry

Returns: void


# redoMoveRows

▸ redoMoveRows(operation: MoveRowsUndoEntry): void

Defined in src/UndoRedo.ts:824 (opens new window)

Parameters:

Name Type
operation MoveRowsUndoEntry

Returns: void


# redoPaste

▸ redoPaste(operation: PasteUndoEntry): void

Defined in src/UndoRedo.ts:786 (opens new window)

Parameters:

Name Type
operation PasteUndoEntry

Returns: void


# redoRemoveColumns

▸ redoRemoveColumns(operation: RemoveColumnsUndoEntry): void

Defined in src/UndoRedo.ts:782 (opens new window)

Parameters:

Name Type
operation RemoveColumnsUndoEntry

Returns: void


# redoRemoveNamedExpression

▸ redoRemoveNamedExpression(operation: RemoveNamedExpressionUndoEntry): void

Defined in src/UndoRedo.ts:845 (opens new window)

Parameters:

Name Type
operation RemoveNamedExpressionUndoEntry

Returns: void


# redoRemoveRows

▸ redoRemoveRows(operation: RemoveRowsUndoEntry): void

Defined in src/UndoRedo.ts:774 (opens new window)

Parameters:

Name Type
operation RemoveRowsUndoEntry

Returns: void


# redoRemoveSheet

▸ redoRemoveSheet(operation: RemoveSheetUndoEntry): void

Defined in src/UndoRedo.ts:812 (opens new window)

Parameters:

Name Type
operation RemoveSheetUndoEntry

Returns: void


# redoRenameSheet

▸ redoRenameSheet(operation: RenameSheetUndoEntry): void

Defined in src/UndoRedo.ts:820 (opens new window)

Parameters:

Name Type
operation RenameSheetUndoEntry

Returns: void


# redoSetCellContents

▸ redoSetCellContents(operation: SetCellContentsUndoEntry): void

Defined in src/UndoRedo.ts:798 (opens new window)

Parameters:

Name Type
operation SetCellContentsUndoEntry

Returns: void


# redoSetColumnOrder

▸ redoSetColumnOrder(operation: SetColumnOrderUndoEntry): void

Defined in src/UndoRedo.ts:857 (opens new window)

Parameters:

Name Type
operation SetColumnOrderUndoEntry

Returns: void


# redoSetRowOrder

▸ redoSetRowOrder(operation: SetRowOrderUndoEntry): void

Defined in src/UndoRedo.ts:853 (opens new window)

Parameters:

Name Type
operation SetRowOrderUndoEntry

Returns: void


# redoSetSheetContent

▸ redoSetSheetContent(operation: SetSheetContentUndoEntry): void

Defined in src/UndoRedo.ts:836 (opens new window)

Parameters:

Name Type
operation SetSheetContentUndoEntry

Returns: void


# saveOperation

▸ saveOperation(operation: UndoEntry): void

Defined in src/UndoRedo.ts:514 (opens new window)

Parameters:

Name Type
operation UndoEntry

Returns: void


# storeDataForVersion

▸ storeDataForVersion(version: number, address: SimpleCellAddress, astHash: string): void

Defined in src/UndoRedo.ts:538 (opens new window)

Stores a formula AST hash snapshot for the given LazilyTransformingAstService version. Skipped when undoLimit is 0 (undo disabled) to avoid storing data that would never be used.

Parameters:

Name Type
version number
address SimpleCellAddress
astHash string

Returns: void


# undo

▸ undo(): void

Defined in src/UndoRedo.ts:569 (opens new window)

Returns: void


# undoAddColumns

▸ undoAddColumns(operation: AddColumnsUndoEntry): void

Defined in src/UndoRedo.ts:626 (opens new window)

Parameters:

Name Type
operation AddColumnsUndoEntry

Returns: void


# undoAddNamedExpression

▸ undoAddNamedExpression(operation: AddNamedExpressionUndoEntry): void

Defined in src/UndoRedo.ts:736 (opens new window)

Parameters:

Name Type
operation AddNamedExpressionUndoEntry

Returns: void


# undoAddRows

▸ undoAddRows(operation: AddRowsUndoEntry): void

Defined in src/UndoRedo.ts:618 (opens new window)

Parameters:

Name Type
operation AddRowsUndoEntry

Returns: void


# undoAddSheet

▸ undoAddSheet(operation: AddSheetUndoEntry): void

Defined in src/UndoRedo.ts:678 (opens new window)

Parameters:

Name Type
operation AddSheetUndoEntry

Returns: void


# undoBatch

▸ undoBatch(batchOperation: BatchUndoEntry): void

Defined in src/UndoRedo.ts:580 (opens new window)

Parameters:

Name Type
batchOperation BatchUndoEntry

Returns: void


# undoChangeNamedExpression

▸ undoChangeNamedExpression(operation: ChangeNamedExpressionUndoEntry): void

Defined in src/UndoRedo.ts:744 (opens new window)

Parameters:

Name Type
operation ChangeNamedExpressionUndoEntry

Returns: void


# undoClearSheet

▸ undoClearSheet(operation: ClearSheetUndoEntry): void

Defined in src/UndoRedo.ts:711 (opens new window)

Parameters:

Name Type
operation ClearSheetUndoEntry

Returns: void


# undoMoveCells

▸ undoMoveCells(operation: MoveCellsUndoEntry): void

Defined in src/UndoRedo.ts:666 (opens new window)

Parameters:

Name Type
operation MoveCellsUndoEntry

Returns: void


# undoMoveColumns

▸ undoMoveColumns(operation: MoveColumnsUndoEntry): void

Defined in src/UndoRedo.ts:659 (opens new window)

Parameters:

Name Type
operation MoveColumnsUndoEntry

Returns: void


# undoMoveRows

▸ undoMoveRows(operation: MoveRowsUndoEntry): void

Defined in src/UndoRedo.ts:652 (opens new window)

Parameters:

Name Type
operation MoveRowsUndoEntry

Returns: void


# undoPaste

▸ undoPaste(operation: PasteUndoEntry): void

Defined in src/UndoRedo.ts:645 (opens new window)

Parameters:

Name Type
operation PasteUndoEntry

Returns: void


# undoRemoveColumns

▸ undoRemoveColumns(operation: RemoveColumnsUndoEntry): void

Defined in src/UndoRedo.ts:602 (opens new window)

Parameters:

Name Type
operation RemoveColumnsUndoEntry

Returns: void


# undoRemoveNamedExpression

▸ undoRemoveNamedExpression(operation: RemoveNamedExpressionUndoEntry): void

Defined in src/UndoRedo.ts:740 (opens new window)

Parameters:

Name Type
operation RemoveNamedExpressionUndoEntry

Returns: void


# undoRemoveRows

▸ undoRemoveRows(operation: RemoveRowsUndoEntry): void

Defined in src/UndoRedo.ts:586 (opens new window)

Parameters:

Name Type
operation RemoveRowsUndoEntry

Returns: void


# undoRemoveSheet

▸ undoRemoveSheet(operation: RemoveSheetUndoEntry): void

Defined in src/UndoRedo.ts:683 (opens new window)

Parameters:

Name Type
operation RemoveSheetUndoEntry

Returns: void


# undoRenameSheet

▸ undoRenameSheet(operation: RenameSheetUndoEntry): void

Defined in src/UndoRedo.ts:701 (opens new window)

Parameters:

Name Type
operation RenameSheetUndoEntry

Returns: void


# undoSetCellContents

▸ undoSetCellContents(operation: SetCellContentsUndoEntry): void

Defined in src/UndoRedo.ts:634 (opens new window)

Parameters:

Name Type
operation SetCellContentsUndoEntry

Returns: void


# undoSetColumnOrder

▸ undoSetColumnOrder(operation: SetColumnOrderUndoEntry): void

Defined in src/UndoRedo.ts:752 (opens new window)

Parameters:

Name Type
operation SetColumnOrderUndoEntry

Returns: void


# undoSetRowOrder

▸ undoSetRowOrder(operation: SetRowOrderUndoEntry): void

Defined in src/UndoRedo.ts:748 (opens new window)

Parameters:

Name Type
operation SetRowOrderUndoEntry

Returns: void


# undoSetSheetContent

▸ undoSetSheetContent(operation: SetSheetContentUndoEntry): void

Defined in src/UndoRedo.ts:723 (opens new window)

Parameters:

Name Type
operation SetSheetContentUndoEntry

Returns: void