PR shows wrong diff

[jrieken]

• opened this Add API function that changes document language vscode#55107
• opened vscode.d.ts inside vscode
• 🐛 the diff showing isn't the diff that shows on github

[rebornix]

Apparently our assumption of how the diff works in Pull Request is, at least, not 100% correct. The logic we use to generate the diff view

• Fetch information from the pull request, and we get two important properties
  • Base. This is the commit that the Pull Request branch HEAD is comparing to AFAIK.
  • Patch. This is the content change we see in the website
• Say we are going to view vscode.d.ts in the diff editor. We will
  • Resolve vscode.d.ts from commit base
  • Based on the vscode.d.ts content from above and the patch, we can get the content from the Pull Request head

It works most of the time, but in this issue, the content of vscode.d.ts from commit base is not the content is not the one the PR is comparing to.

[rebornix]

GitHub Visual Studio ran into the same issue and got fixed via github/VisualStudio#1008

[rebornix]

Already fixed.