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The Many SHAs of a GitHub Pull Request
Executing a GitHub Action for a pull request creates a surprising number of SHA commits. Learn the purpose of the different SHAs and when to use each one.
Many people don’t realize it, but pull requests actually have multiple “identities” when an Action workflow runs. At the same time, calls to the Status or Checks API need access to the SHA associated with the HEAD of the branch being merged. github.merge_commit_sha This is a temporary commit that is created behind the scenes for the test merge that validated no conflicts exist with the base branch.
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