Terminal.Gui/Tests/MIGRATION_STATUS.md

Test Migration to UnitTests.Parallelizable - Status Report

Executive Summary

Current Status (Commit d4fd965):

• 119 tests successfully migrated to UnitTests.Parallelizable
• 9,476 tests passing in Parallelizable (up from 9,357 baseline)
• Migration rate: 8.2% of original 1,446 tests in UnitTests
• check-duplicates workflow: ✅ Passing
• All tests: ✅ Passing

Migration Breakdown

Successfully Migrated (119 tests)

Pure Unit Tests (26 tests - No driver needed)

1. StackExtensionsTests.cs - 10 tests for Stack extensions
2. TabTests.cs - 1 constructor test
3. AnsiMouseParserTests.cs - 14 ANSI mouse parsing tests
4. Dim.FillTests.cs - 1 test (merged with existing)

Refactored Tests (93 tests - Using local FakeDriver)

TextFormatterTests.cs - 10 Draw methods refactored:

1. Draw_Horizontal_Centered - 11 test cases
2. Draw_Horizontal_Justified - 11 test cases
3. Draw_Horizontal_Left - 9 test cases
4. Draw_Horizontal_Right - 8 test cases
5. Draw_Horizontal_RightLeft_BottomTop - 11 test cases
6. Draw_Horizontal_RightLeft_TopBottom - 11 test cases
7. Draw_Vertical_BottomTop_LeftRight - 11 test cases
8. Draw_Vertical_BottomTop_RightLeft - 11 test cases
9. Draw_Vertical_TopBottom_LeftRight - 3 test cases
10. Draw_Vertical_TopBottom_LeftRight_Top - 8 test cases

Refactoring Pattern Used:

public void TestMethod (params)
{
    // Create local driver instance
    var factory = new FakeDriverFactory ();
    var driver = factory.Create ();
    driver.SetBufferSize (width, height);
    
    // Pass driver explicitly to methods
    textFormatter.Draw (rect, attr1, attr2, driver: driver);
    
    // Extract and assert results
    string actual = GetDriverContents (driver, width, height);
    Assert.Equal (expected, actual);
}

Remaining Work

TextFormatterTests.cs (8 tests remaining)

Status Analysis:

1. Draw_Vertical_TopBottom_LeftRight_Middle

   • Can migrate: Yes, with helper enhancement
   • Complexity: Returns Rectangle, validates Y position
   • Action needed: Enhance helper to return position info

2. Draw_Vertical_Bottom_Horizontal_Right

   • Can migrate: Yes, with helper enhancement
   • Complexity: Returns Rectangle, validates Y position
   • Action needed: Same as above

3. Draw_Text_Justification

   • Can migrate: Yes
   • Complexity: Multi-parameter test
   • Action needed: Standard refactoring pattern

4. Justify_Horizontal

   • Can migrate: Yes
   • Complexity: Standard Draw test
   • Action needed: Standard refactoring pattern

5. FillRemaining_True_False

   • Can migrate: Need investigation
   • Complexity: May modify state beyond driver
   • Action needed: Review implementation

6. UICatalog_AboutBox_Text

   • Can migrate: Need investigation
   • Complexity: May load external resources
   • Action needed: Review dependencies

7. FormatAndGetSize_Returns_Correct_Size

   • Can migrate: Need investigation
   • Complexity: May require specific driver capabilities
   • Action needed: Review method signature

8. FormatAndGetSize_WordWrap_False_Returns_Correct_Size

   • Can migrate: Need investigation
   • Complexity: May require specific driver capabilities
   • Action needed: Review method signature

Other Files with SetupFakeDriver (34 files)

Files requiring systematic review:

1. CursorTests.cs
2. FakeDriverTests.cs
3. LineCanvasTests.cs
4. RulerTests.cs
5. AdornmentTests.cs
6. BorderTests.cs
7. MarginTests.cs
8. PaddingTests.cs
9. ShadowStyleTests.cs
10. AllViewsDrawTests.cs
11. ClearViewportTests.cs
12. ClipTests.cs
13. DrawTests.cs
14. TransparentTests.cs
15. LayoutTests.cs
16. Pos.CombineTests.cs
17. NavigationTests.cs
18. TextTests.cs
19. AllViewsTests.cs
20. ButtonTests.cs
21. CheckBoxTests.cs
22. ColorPickerTests.cs
23. DateFieldTests.cs
24. LabelTests.cs
25. RadioGroupTests.cs
26. ScrollBarTests.cs
27. ScrollSliderTests.cs
28. TabViewTests.cs
29. TableViewTests.cs
30. TextFieldTests.cs
31. ToplevelTests.cs
32. TreeTableSourceTests.cs
33. TreeViewTests.cs
34. SetupFakeDriverAttribute.cs (infrastructure)

For each file, need to determine:

• Which tests use methods that accept driver parameters → Migratable
• Which tests require View hierarchy/Application context → Likely non-migratable
• Which tests modify global state → Non-migratable

Non-Migratable Tests (TBD - Requires detailed analysis)

Common reasons tests CANNOT be migrated:

1. Requires Application.Init() - Tests that need event loop, application context
2. Tests View hierarchy - Tests that rely on View parent/child relationships requiring Application
3. Modifies ConfigurationManager - Tests that change global configuration state
4. Requires specific driver features - Tests that depend on platform-specific driver behavior
5. Integration tests - Tests validating multiple components together with Application context

Recommendations

1. Complete TextFormatterTests migration - 4-6 tests clearly migratable
2. Systematic file-by-file review - Categorize each of the 34 remaining files
3. Document non-migratable - For each test that cannot be migrated, document specific reason
4. Consider test refactoring - Some integration tests could be split into unit + integration parts
5. Update guidelines - Document patterns for writing parallelizable tests

Technical Notes

Why Some Tests Must Remain in UnitTests

Many tests in UnitTests are correctly placed integration tests that should NOT be parallelized:

• They test View behavior within Application context
• They validate event handling through Application.MainLoop
• They test ConfigurationManager integration
• They verify driver-specific platform behavior
• They test complex component interactions

These are valuable integration tests and should remain in UnitTests.

Pattern for Future Test Development

New tests should default to UnitTests.Parallelizable unless they:

1. Require Application.Init()
2. Test View hierarchy interactions
3. Modify global state (ConfigurationManager, Application properties)
4. Are explicitly integration tests