Consolidate the sync-* workflows

[dscho]

In preparation for supporting projects other than Git, let's combine the sync-git-gui and sync-gitster-git workflows into a single, matrix one. The next step after that will be to define the project-specific parts in a project configuration and consume it from there.

While at it, also rename the workflow that synchronizes the mailing list mirror, so that it does not talk about Git specifically.

[dscho]

I also noticed that it makes no sense to introduce kebap-cased matrix variables only to switch them to CamelCased ones later. Instead, I now introduce CamelCased ones right away.

Range-diff

• 1: 5eb6540 ! 1: 7a1ca71 sync-upstream-branches: turn the workflow into a matrix

  @@ .github/workflows/sync-upstream-branches.yml: concurrency:
   +    strategy:
   +      matrix:
   +        spec:
  -+          - source-repo: j6t/git-gui
  -+            target-repo: gitgitgadget/git
  -+            target-ref-namespace: git-gui/
  ++          - sourceRepo: j6t/git-gui
  ++            targetRepo: gitgitgadget/git
  ++            targetRefNamespace: git-gui/
   +
        steps:
          - name: check which refs need to be synchronized
  @@ .github/workflows/sync-upstream-branches.yml: concurrency:
            with:
              script: |
   -            const [targetRepoOwner, targetRepoName] = process.env.TARGET_REPOSITORY.split('/')
  -+            const sourceRepo = ${{ toJSON(matrix.spec.source-repo) }}
  -+            const targetRepo = ${{ toJSON(matrix.spec.target-repo) }}
  -+            const targetRefNamespace = ${{ toJSON(matrix.spec.target-ref-namespace) }}
  ++            const sourceRepo = ${{ toJSON(matrix.spec.sourceRepo) }}
  ++            const targetRepo = ${{ toJSON(matrix.spec.targetRepo) }}
  ++            const targetRefNamespace = ${{ toJSON(matrix.spec.targetRefNamespace) }} || ''
   +
   +            const [targetRepoOwner, targetRepoName] = targetRepo.split('/')
                core.setOutput('target-repo-owner', targetRepoOwner)
  @@ .github/workflows/sync-upstream-branches.yml: jobs:
   +            const targetRefs = await getRefs(targetRepo, targetRefNamespace)
    
   -            const targetPrefix = `refs/heads/${process.env.TARGET_REF_NAMESPACE}`
  -+            const targetPrefix = targetRefNamespace ? `refs/heads/${targetRefNamespace}` : 'refs/heads/'
  ++            const targetPrefix = `refs/heads/${targetRefNamespace}`
    
                const refspecs = []
                const toFetch = new Set()
  @@ .github/workflows/sync-upstream-branches.yml: jobs:
              git init --bare
    
   -          git remote add source "${{ github.server_url }}/$SOURCE_REPOSITORY"
  -+          git remote add source '${{ github.server_url }}/${{ matrix.spec.source-repo }}'
  ++          git remote add source '${{ github.server_url }}/${{ matrix.spec.sourceRepo }}'
              # pretend to be a partial clone
              git config remote.source.promisor true
              git config remote.source.partialCloneFilter blob:none
  @@ .github/workflows/sync-upstream-branches.yml: jobs:
              printf '%s' '${{ steps.check.outputs.refspec }}' |
              xargs -d ' ' -r git -c http.extraHeader='${{ steps.auth.outputs.header }}' \
   -            push "${{ github.server_url }}/$TARGET_REPOSITORY"
  -+            push '${{ github.server_url }}/${{ matrix.spec.target-repo }}'
  ++            push '${{ github.server_url }}/${{ matrix.spec.targetRepo }}'

• 2: 5cbbf3c = 2: 6cc9af2 sync-upstream-branches: adopt a more functional style

• 3: 792313e ! 3: 265711c sync-upstream-branches: take over the job of the sync-gitster-git workflow

  @@ .github/workflows/sync-gitster-git.yml (deleted)
   
    ## .github/workflows/sync-upstream-branches.yml ##
   @@ .github/workflows/sync-upstream-branches.yml: jobs:
  -           - source-repo: j6t/git-gui
  -             target-repo: gitgitgadget/git
  -             target-ref-namespace: git-gui/
  -+          - source-repo: gitster/git
  -+            target-repo: gitgitgadget/git
  -+            source-ref-regex: "^refs/heads/(maint-\\d|[a-z][a-z]/)"
  +           - sourceRepo: j6t/git-gui
  +             targetRepo: gitgitgadget/git
  +             targetRefNamespace: git-gui/
  ++          - sourceRepo: gitster/git
  ++            targetRepo: gitgitgadget/git
  ++            sourceRefRegex: "^refs/heads/(maint-\\d|[a-z][a-z]/)"
    
        steps:
          - name: check which refs need to be synchronized
   @@ .github/workflows/sync-upstream-branches.yml: jobs:
            with:
              script: |
  -             const sourceRepo = ${{ toJSON(matrix.spec.source-repo) }}
  -+            const sourceRefRegexp = ((p) => p ? new RegExp(p) : null)(${{ toJSON(matrix.spec.source-ref-regex) }})
  -             const targetRepo = ${{ toJSON(matrix.spec.target-repo) }}
  -             const targetRefNamespace = ${{ toJSON(matrix.spec.target-ref-namespace) }}
  +             const sourceRepo = ${{ toJSON(matrix.spec.sourceRepo) }}
  ++            const sourceRefRegexp = ((p) => p ? new RegExp(p) : null)(${{ toJSON(matrix.spec.sourceRefRegex) }})
  +             const targetRepo = ${{ toJSON(matrix.spec.targetRepo) }}
  +             const targetRefNamespace = ${{ toJSON(matrix.spec.targetRefNamespace) }} || ''
    
   @@ .github/workflows/sync-upstream-branches.yml: jobs:
                        await github.rest.git.listMatchingRefs({

• 4: c682136 = 4: ca0a54d sync-git-mailing-list-mirror: start making the workflow more generic

• 5: 36d1292 = 5: 3c327fc sync-mailing-list-mirror: use more elegant cron definition

[webstech]

I'll let you complete this so you can control the timing.