How to run snapshot tests on docfx forked repository

[filzrev]

When running snapshot tests on local environment with docfx forked repository.
A lot of diffs occurs.

It can be reduced by following steps.

1. Enable snapshot tests
By default. SnapShot tests is skipped for non-CI environment.
It need to set environment variable to run these tests.

1.1. Edittest\docfx.Snapshot.Tests\ModuleInitializer.cs
1.2. Add following line.> Environment.SetEnvironmentVariable("SNAPSHOT_TEST", "EnableSnapshotTest");

2. Modify src\Docfx.Common\Git\GitUtility.cs file

Modify following functions to replace repository dependent string.

• TryGetFileDetail
• RawContentUrlToContentUrl
• GetSourceUrl

(e.g. `url.Replace("filzrev", "dotnet").Replace(".git", "");

[yufeih]

OS/hardware setup may affect screenshot test output, so it is excluded from locally. We can perhaps replace the current approach with a visual regression test service such as percy which is free to open source projects. Other suggestions on visual regression services are also welcome.

[yufeih]

We are now using Percy for visual testing and snapshot tests can run locally now.

[filzrev]

Thanks for updates.
Is it expected to create my own percy account to tests?

I'm trying to run percy tests with following steps.
And successfully compare screenshots.

Steps to execute percy tests at local environment

1. Create https://percy.io account. And create project.
2. Install percy CLI. with following command

npm i -g @percy/cli

3. Create snapshots of main branch

git switch main
$env:PERCY_TOKEN = '[Write-only Token]'

dotnet build -c Release
percy exec -- dotnet test -c Release -f net8.0 --no-build --filter Stage=Percy

4. Approve main branch snapshots from percy's project web site.

5. Create snapshots of my-feature-branch.

git switch [my-feature-branch]
$env:PERCY_TOKEN = '[Write-only Token]'
$env:PERCY_TARGET_BRANCH = 'main'

dotnet build -c Release
percy exec -- dotnet test -c Release -f net8.0 --no-build --filter Stage=Percy

[yufeih]

No - there were sth wrong with PERCY_TOKEN not exposed to forked PRs which should be resolved now.