test: improve test coverage for pkg/datasource/sql/undo

[LucienShen-Liu]

What this PR does:improve test coverage for pkg/datasource/sql/undo

Which issue(s) this PR fixes: #940

Fixes #

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

[Copilot]

Pull Request Overview

This PR adds comprehensive unit test coverage for the undo logging functionality in the SQL datasource package. The tests validate manager registration, builder patterns, executor interfaces, and configuration handling for the undo log system.

• Unit tests added for core undo functionality including manager, builder, and executor interfaces
• Configuration and compression handling test coverage
• MySQL-specific undo log manager implementation tests

Reviewed Changes

Copilot reviewed 10 out of 11 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
pkg/datasource/sql/undo/undo_test.go	Tests for undo log manager registration, builder patterns, and core data structures
pkg/datasource/sql/undo/undo_executor_test.go	Tests for undo executor interface implementation
pkg/datasource/sql/undo/undo_executor_holder_test.go	Tests for undo executor holder interface and factory methods
pkg/datasource/sql/undo/mysql/undo_test.go	Tests for MySQL-specific undo log manager implementation
pkg/datasource/sql/undo/mysql/default_test.go	Tests for MySQL undo log manager initialization
pkg/datasource/sql/undo/factor/undo_executor_holder_factor_test.go	Tests for undo executor holder factory with lazy initialization
pkg/datasource/sql/undo/factor/undo_executor_factory_test.go	Tests for undo executor factory and SQL type routing
pkg/datasource/sql/undo/config_test.go	Tests for undo configuration and flag registration
pkg/datasource/sql/undo/base/undo_test.go	Tests for base undo log manager utility functions
go.mod	Updated to include testify mock dependency
go.sum	Checksum for testify objx dependency

---

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[Copilot]

Corrected spelling of 'UndoLogStatueNormnal' to 'UndoLogStatusNormal'. The constant name contains typo 'Statue' instead of 'Status' and 'Normnal' instead of 'Normal'.

Suggested change

	logStatus: UndoLogStatueNormnal,
	logStatus: UndoLogStatusNormal,

[LucienShen-Liu]

The issue was a spelling error in the original constant name; it has now been corrected.

[Copilot]

Corrected spelling of 'UndoLogStatue' to 'UndoLogStatus'. The type name contains typo 'Statue' instead of 'Status'.

Suggested change

	logStatus UndoLogStatue
	want bool
	}{
	{
	name: "can undo - normal status",
	logStatus: UndoLogStatueNormnal,
	want: true,
	},
	{
	name: "cannot undo - global finished",
	logStatus: UndoLogStatueGlobalFinished,
	logStatus UndoLogStatus
	want bool
	}{
	{
	name: "can undo - normal status",
	logStatus: UndoLogStatusNormal,
	want: true,
	},
	{
	name: "cannot undo - global finished",
	logStatus: UndoLogStatusGlobalFinished,

[LucienShen-Liu]

The issue was a spelling error in the original constant name; it has now been corrected.

[Copilot]

Corrected spelling of 'UndoLogStatueGlobalFinished' to 'UndoLogStatusGlobalFinished'. The constant name contains typo 'Statue' instead of 'Status'.

Suggested change

	logStatus: UndoLogStatueGlobalFinished,
	logStatus: UndoLogStatusGlobalFinished,

[LucienShen-Liu]

The issue was a spelling error in the original constant name; it has now been corrected.

[codecov-commenter]

Codecov Report

❌ Patch coverage is 25.00000% with 3 lines in your changes missing coverage. Please review.
✅ Project coverage is 45.90%. Comparing base (4420143) to head (7888315).

Files with missing lines	Patch %	Lines
pkg/datasource/sql/undo/base/undo.go	0.00%	3 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #971      +/-   ##
==========================================
- Coverage   46.33%   45.90%   -0.43%     
==========================================
  Files         195      200       +5     
  Lines       11887    12264     +377     
==========================================
+ Hits         5508     5630     +122     
- Misses       5943     6196     +253     
- Partials      436      438       +2     

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[Code-Fight]

@LucienShen-Liu pls resolve conflicts

[LucienShen-Liu]

@LucienShen-Liu pls resolve conflicts

done