generating-upgrade-test-baseline

name	generating-upgrade-test-baseline
description	Generates behavior-locking tests before a .NET upgrade using the external dotnet-test plugin. Use when executing a generate-test-baseline task for projects with upgrade compatibility risks.
metadata	{"traits":"(CopilotCli|VsCode|GitHubCopilotApp) & (.NET|CSharp|VisualBasic|DotNetCore)","discovery":"lazy","importance":"high"}

Generating an Upgrade Test Baseline

Use the external code-testing-generator agent to create tests that lock in current behavior before the upgrade changes production code. The generator owns test-framework detection, test-project selection or creation, implementation, build, test, fix, lint, and final validation.

Prerequisite

Read the ## Test Baseline status from scenario-instructions.md. If it is not enabled, complete generate-test-baseline as skipped without invoking the generator.

The code-testing-generator agent from the dotnet-test plugin is required. If it is unavailable, load managing-dotnet-test-installation and follow it before continuing.

Requirements

• Generate tests only for production projects, never for test projects.
• Do not change production code while establishing the baseline.
• Keep generation within the project scope recorded in scenario-instructions.md.
• Treat API.0003 behavioral changes as must-cover upgrade risks.

Prepare the Generator Brief

1. Read the ## Test Baseline block from scenario-instructions.md. Use its Projects list as the exact production-project scope.
2. For each project, query the assessment for:
   • API.0003 issues as must-cover behavioral changes.
   • API.0002 and API.0001 issues as priority seeds.
   • The issue location, code sample, and documentation URL when available.
3. Invoke code-testing-generator with a goal-oriented brief:

## Goal
Create a regression safety-net before upgrading {ProjectScope} from {current TFM} to {target TFM}.
Lock in current observable behavior so post-upgrade validation can detect regressions.

## Scope
Generate tests only for: {ProjectScope}
Do not modify production code.

## Must cover
{API.0003 call sites and documented behavior changes}

## Priority seeds
{API.0002 and API.0001 call sites}

## Additional research
Within the project scope, identify other behavior likely to change during this upgrade, including
package behavior, serialization, culture and formatting, date/time, ordering, hashing, regex,
encoding, file I/O, and concurrency. Prefer depth on plausible upgrade risks over broad coverage.

The brief supplies upgrade-specific risk context; it does not replace the generator's own research, planning, or validation pipeline.

Integrate the Result

After code-testing-generator succeeds:

1. Update scenario-instructions.md: under ## Test Baseline, add the project-file path of every test project used beneath Test projects.
2. If the generator created a test project:
   • Confirm the project is registered in the repository's solution file.
   • Update plan.md: add the new project-file path to the applicable upgrade task description so the normal conversion flow retargets it to the target framework before validate-test-baseline. Do not add scope details to tasks.md; it tracks task status only.
3. Complete the task when the generator reports that the generated tests build and pass on the pre-upgrade code.

Generation Failure

Failure to establish a green baseline must not block the upgrade. Follow the Test Coverage generation-failure flow for the user decision and required option-state updates.