yann-achard-MS

This commit **fixes multiple logical issues** within the **`RangeMap.union` method** in the **`dds/tree` package**. The `union` method has been **rewritten** to correctly merge ranges by iterating and setting entries from the second map, ensuring proper handling of overlapping keys. This **bug fix** is accompanied by **new, comprehensive test cases** in `rangeMap.spec.ts` to validate the corrected logic. While the issues were not known to affect user-facing behavior, this change significantly improves the **internal correctness** of `RangeMap` operations, though a performance improvement will be addressed in a separate PR.

This commit **reverts** a previous change that introduced more detailed error messages within the **`simple-tree` package's tree construction logic**, specifically impacting `unhydratedFlexTreeFromInsertable.ts`. This **temporary maintenance revert** simplifies error messages and removes related helper functions to resolve an issue with a **downstream integration pipeline** that was overly sensitive to the previous detailed error output. Test assertions in `treeNodeApi.spec.ts`, `recordNode.spec.ts`, and `unhydratedFlexTreeFromInsertable.spec.ts` have been updated to reflect these simplified error expectations. Consequently, users will temporarily receive less specific error information during tree construction until the original, enhanced error reporting can be safely re-merged.

This commit **refactors** the **testing suite** for the `SharedTreeChangeFamily` within the `dds/tree` package. Specifically, it simplifies the **enrichment testing** by introducing a mock interface and helper functions in `sharedTreeChangeFamily.spec.ts`. This **improves the readability and maintainability** of the tests by factoring out complex mocking logic and streamlining test inputs and assertions. As a **test-only refactoring**, this change has no impact on runtime behavior or public APIs, but enhances the developer experience for future test maintenance.

This commit **improves the robustness of staged schema upgrade tests** within the `packages/dds/tree` module, specifically in `packages/dds/tree/src/test/simple-tree/api/stagedSchemaUpgrade.spec.ts`. It modifies the tests to be more conservative, no longer assuming that a tree is safe to read from after an exception during an upgrade. Instead, the tests now create new views or use additional trees to ensure a clean state for subsequent operations. This **test improvement** anticipates future production code changes, such as explicit tree breakage on error, ensuring the tests remain reliable and prevent false positives.

This commit **reverts a prior change** by **re-introducing skip conditions** in the `stashedOps.spec.ts` end-to-end test. Specifically, it restores the skip for non-local drivers and comments out a line related to ID compression within the **offline stashed operations forking test**. This **maintenance fix** addresses **intermittent test failures** that were occurring multiple times a day after the skips were initially removed. The change temporarily **disables certain test flavors** to stabilize CI/CD, indicating an underlying issue with stashed ops forking in non-local environments that requires further investigation.

This commit **reverts the ID sharding feature** that was previously introduced, specifically undoing the changes from `microsoft/FluidFramework#26294` because it caused a breakage in a downstream integration pipeline. The core **`id-compressor` package** is significantly affected, with all sharding-related state, methods like `shard` and `unshard`, and serialization logic being removed, and eager final ID generation re-enabled. This **refactoring** also removes `SerializationVersion` imports and parameters from `shared-tree`, `container-runtime`, and numerous test files across various packages, simplifying the `IdCompressor` API. The primary impact is a **bug fix** that stabilizes a critical downstream integration, ensuring compatibility and restoring expected behavior.

This commit **fixes a critical bug** in the **DDS Tree's `sequence-field` implementation** related to **multi-step moves of array elements**. Previously, inverting these operations (for rollback or revert) failed to correctly update the final endpoints with the new revision, leading to errors during reverts and potential document corruption during reconciliation. This **bug fix** ensures that the final endpoints are correctly updated, making multi-step move operations safe. It prevents peers from entering a broken read-only state during reverts and avoids document corruption when reconciling edits with concurrent operations. New tests have been added to verify the corrected undo/redo and rebase behavior for multi-step moves.

This commit introduces a **new feature** to the **`RangeMap` utility** within the `dds/tree` package. The `delete` method in `packages/dds/tree/src/util/rangeMap.ts` has been enhanced to **return the count of key-value pairs that were successfully deleted**. This modification provides more explicit feedback on deletion operations and is a **prerequisite** for an upcoming feature enabling **detach-attach edits** within the tree data structure. Existing tests for `RangeMap` have been updated to assert this new return value.

This commit introduces **asynchronous transaction support** to the **`@fluidframework/tree`** package, enabling tree modifications to span `await` calls within the **SharedTree** and **SimpleTree** DDS. It provides a **new capability** via the `@alpha` `runTransactionAsync` API, implemented in `schematizingTreeView.ts` and exposed through `simple-tree/api/tree.ts`. The core transaction logic in `transaction.ts` was **refactored** to handle both synchronous and asynchronous operations, requiring existing synchronous transaction calls to be updated to explicitly use `start(false)`. This enhancement allows for more flexible and complex data manipulation patterns while maintaining transactional integrity.

This commit **refactors** the internal handling of **persisted format numbers** within the **`SharedTree`** and **`ModularChange`** systems. It transitions from using branded numbers to **`strictEnum`** for `SharedTreeChangeFormatVersion` and `ModularChangeFormatVersion`, primarily affecting `sharedTreeChangeCodecs.ts` and `defaultFieldKinds.ts`. This **refactoring** effort aims to **reduce the risk of invalid version numbers** being used and improve the discoverability of documentation associated with each format version. The change impacts the core **`packages/dds/tree`** module, enhancing the robustness and maintainability of its change serialization mechanisms.

This commit **fixes** an issue within the **`DDS Tree` `ModularChangeFamily` codec system** by **removing references to unsupported codec version numbers**. Specifically, it cleans up the `makeModularChangeCodecFamily` function in `packages/dds/tree/src/feature-libraries/modular-schema/modularChangeCodecs.ts` by eliminating switch cases for versions 1, 2, and 6, which were never properly implemented. The associated tests in `packages/dds/tree/src/test/feature-libraries/modular-schema/modularChangeFamily.spec.ts` are also updated to only validate currently supported versions 3 and 4. This **maintenance** task removes dead code and prevents potential issues from invalid codec version handling, preparing the system for a future `strictEnum` implementation.

This commit **fixes** a bug in the **`dds/tree` package's revision replacement logic** where it incorrectly handled **contiguous ID ranges**. It **enhances** the `DefaultRevisionReplacer` and related utilities to correctly update `AtomId`s and local IDs across these ranges, ensuring proper rebase operations within the **modular-schema** and **sequence-field** feature libraries. The change involves **refactoring** the `RevisionReplacer` interface to support ID ranges and updating various functions to pass necessary `count` parameters for accurate range processing. This **bug fix** is crucial for the correctness of **tree rebase tests**, preventing errors in scenarios involving ID range updates.

This commit introduces a **refactoring** of the **`delta` data structure** within the **`dds/tree` package**, specifically by wrapping `marks` arrays in a new `FieldChanges` object defined in `src/core/tree/delta.ts`. This **architectural improvement** allows for future extensibility, enabling the addition of new fields alongside the marks, such as information about the re-attachability of detached nodes. Various components across **`core/tree`** and **`feature-libraries`**, including `deltaUtil`, `visitDelta`, `forestSummarizer`, and several field kind implementations, have been updated to conform to this new object structure. This ensures all parts of the tree system correctly process the refactored delta information, preparing for more sophisticated change tracking.

This commit **re-enables and fixes testing** for **`ModularChangeset` encoding** within the `tree` package, resolving a bug in `makeEncodingTestSuite` that previously prevented tests from running. It significantly **broadens the test coverage** for `ModularChangeset` encoding by introducing more codec configurations and version-specific tests. Concurrently, a **robustness fix** is applied to `ModularChangeFamily.getRevisions` in the `modular-schema` library, making it more resilient to malformed changes where `change.revisions` might be undefined or empty. This work ensures more comprehensive validation of change encoding and enhances the overall stability of the **tree data structure's change processing**.

This commit **refactors and re-implements the commit enrichment system** within the **`dds/tree`** package, primarily affecting the **`SharedTreeCore`** and **`TreeCheckout`** components. The **refactoring simplifies the enrichment logic** by centralizing the responsibility of providing the correct view state for enrichment within `TreeCheckout`, which now directly implements the `ChangeEnricher` interface. This **enhances maintainability and robustness**, preparing the system for transactions that span multiple JavaScript turns. The new design also **improves performance** through lazy and batched enrichment, reducing computational overhead, and simplifies the API for consumers like `DefaultResubmitMachine`.

This commit introduces a significant **refactoring** of the **revision replacement mechanism** within the **`SharedTree`** and **`ModularChangeFamily`** to support more general and robust handling of change revisions. It addresses critical limitations where `localId` values could collide across different revisions and `ChangeAtomId` mapping was inconsistent across modular changesets. This is achieved by introducing a new `RevisionReplacer` interface and a `ChangeAtomIdBTree` for efficient atom ID management, primarily impacting the `packages/dds/tree` package. This foundational **enhancement** is crucial for enabling advanced features like **merging and reverting operations within open transactions** by providing a more reliable system for tracking and transforming changes.

This commit **refactors** the **revision ID management** within **tree transactions** to streamline how changesets are composed. Instead of individual transaction steps minting unique revision IDs that are later remapped, all intermediate changes within a transaction now immediately use the final transaction's revision ID. This **simplifies the `shared-tree-core` transaction logic**, eliminating the need for post-composition ID renaming, and reducing the total number of revision tags minted. The change improves the robustness of the **tree data structure** by making components like `DetachedFieldIndex` oblivious to complex ID remapping, and better supports future features like merging or reverting within open transactions.

This commit **introduces new restrictions** to the **`TreeBranch` API** within the **`shared-tree` DDS**, preventing operations that could expose branches to incomplete or invalid transaction states. Specifically, the `fork()`, `merge()`, and `rebaseOnto()` methods will now **throw a `UsageError`** if a transaction is active on the branch or its source/target. This **feature** is a **breaking change** for the beta `TreeBranch` methods, ensuring application invariants are upheld by insulating dependents from potentially inconsistent data during ongoing transactions.

This commit **refactors** the **`TransactionStack`** within the **`@fluidframework/tree`** package to enhance its handling of **nested transactions**. The `onPush` callback in `TransactionStack` can now return a new `onPush` callback, providing a more flexible mechanism for managing the lifecycle of subsequent inner transactions. This change is specifically leveraged by **`SquashingTransactionStack`** to cleanly separate the logic for inner and outer transactions, eliminating redundant `isInProgress()` checks and allowing for more robust state management. This **architectural improvement** simplifies the transaction system's internal logic and **paves the way for future enhancements** involving more complex transaction state.

This commit provides a **bug fix** for the **SharedTree** module, resolving a critical issue where **transaction aborts** could leave the tree in a broken state, preventing subsequent **undo/redo functionality** and triggering asserts. The problem occurred because `TreeCheckout` would replace its `DetachedFieldIndex` instance on rollback, causing `SharedTreeReadonlyChangeEnricher` to read from an outdated instance. The fix introduces a **checkpointing mechanism** for `DetachedFieldIndex` within **TreeCheckout**, allowing its state to be saved and restored on transaction aborts without replacing the instance. This ensures the **SharedTree** remains consistent and **undo/redo functionality** works reliably after transaction rollbacks, significantly improving the stability of the **tree data structure**. Additionally, it includes a **refactoring** to introduce a `ReadOnlyDetachedFieldIndex` interface for better encapsulation.