ci: use the brand-new GitHub Action to download git-sdk-64-minimal

In our continuous builds, Windows is the odd cookie that requires a
complete development environment to be downloaded because it is not
installed by default.

Side note: technically, there _is_ a development environment: MSYS2. But
it differs from Git for Windows' SDK in subtle points, enough so to
prevent Git's test suite from running without failures.

Traditionally, we support downloading this environment (which we
nicknamed `git-sdk-64-minimal`) via a PowerShell scriptlet that accesses
the build artifacts of a dedicated Azure Pipeline (which packages a tiny
subset of the full Git for Windows SDK, containing just enough to build
Git and run its test suite).

This PowerShell script is unfortunately not very robust and sometimes
due to network issues.

Instead of doing all of this in Git's own `.github/workflows/`, let's
offload this logic to the brand-new GitHub Action at
https://github.com/marketplace/actions/setup-git-for-windows-sdk

This Action not only downloads and extracts git-sdk-64-minimal _outside_
the worktree (making it no longer necessary to meddle with
`.gitignore`), it also adds the `bash.exe` to the `PATH` and sets the
environment variable `MSYSTEM` (an implementation detail that Git's
workflow should never have needed to know about).

This allows us to convert all those funny PowerShell tasks that wanted
to call git-sdk-64-minimal's `bash.exe`: they all are now regular `bash`
scriptlets.

This finally lets us get rid of the funny quoting and escaping where we
had to pay attention not only to quote and escape in the Bash scriptlets
properly, but also to add a second level of escaping (with backslashes
for double quotes and backticks for dollar signs) so that PowerShell
would not do unintended things.

Further, this Action uses a fast caching strategy native to GitHub
Actions that is not only very fast, but should accelerate the download
across CI runs: git-sdk-64-minimal is usually updated once per 24h, and
needs to be cached only once within that period.

With this we can drop the homerolled caching where we try to accelerate
the test phase by uploading git-sdk-64-minimal as a workflow artifact
after using it to build Git, and then download it as workflow artifact
in the test phase.

Even better: the `vs-test` job no longer needs to depend on the
`windows-build` job. The only reason it depended on it was to ensure
that the workflow artifact was available.

Signed-off-by: Johannes Schindelin <[email protected]>

Author: dscho

.github/workflows/main.yml

@@ -82,43 +82,18 @@ jobs:
     runs-on: windows-latest
     steps:
     - uses: actions/checkout@v1
-    - name: download git-sdk-64-minimal
-      shell: bash
-      run: |
-        ## Get artifact
-        urlbase=https://dev.azure.com/git-for-windows/git/_apis/build/builds
-        id=$(curl "$urlbase?definitions=22&statusFilter=completed&resultFilter=succeeded&\$top=1" |
-          jq -r ".value[] | .id")
-        download_url="$(curl "$urlbase/$id/artifacts" |
-          jq -r '.value[] | select(.name == "git-sdk-64-minimal").resource.downloadUrl')"
-        curl --connect-timeout 10 --retry 5 --retry-delay 0 --retry-max-time 240 \
-          -o artifacts.zip "$download_url"
-
-        ## Unzip and remove the artifact
-        unzip artifacts.zip
-        rm artifacts.zip
+    - uses: git-for-windows/setup-git-for-windows-sdk@v1
     - name: build
-      shell: powershell
+      shell: bash
       env:
         HOME: ${{runner.workspace}}
-        MSYSTEM: MINGW64
         NO_PERL: 1
-      run: |
-        & .\git-sdk-64-minimal\usr\bin\bash.exe -lc @"
-        printf '%s\n' /git-sdk-64-minimal/ >>.git/info/exclude
-
-          ci/make-test-artifacts.sh artifacts
-        "@
+      run: ci/make-test-artifacts.sh artifacts
     - name: upload build artifacts
       uses: actions/upload-artifact@v1
       with:
         name: windows-artifacts
         path: artifacts
-    - name: upload git-sdk-64-minimal
-      uses: actions/upload-artifact@v1
-      with:
-        name: git-sdk-64-minimal
-        path: git-sdk-64-minimal
   windows-test:
     runs-on: windows-latest
     needs: [windows-build]
@@ -136,25 +111,14 @@ jobs:
     - name: extract build artifacts
       shell: bash
       run: tar xf artifacts.tar.gz
-    - name: download git-sdk-64-minimal
-      uses: actions/download-artifact@v1
-      with:
-        name: git-sdk-64-minimal
-        path: ${{github.workspace}}/git-sdk-64-minimal/
+    - uses: git-for-windows/setup-git-for-windows-sdk@v1
     - name: test
-      shell: powershell
-      run: |
-        & .\git-sdk-64-minimal\usr\bin\bash.exe -lc @"
-          # Let Git ignore the SDK
-          printf '%s\n' /git-sdk-64-minimal/ >>.git/info/exclude
-
-          ci/run-test-slice.sh ${{matrix.nr}} 10
-        "@
+      shell: bash
+      run: ci/run-test-slice.sh ${{matrix.nr}} 10
     - name: ci/print-test-failures.sh
       if: failure()
-      shell: powershell
-      run: |
-        & .\git-sdk-64-minimal\usr\bin\bash.exe -lc ci/print-test-failures.sh
+      shell: bash
+      run: ci/print-test-failures.sh
     - name: Upload failed tests' directories
       if: failure() && env.FAILED_TEST_ARTIFACTS != ''
       uses: actions/upload-artifact@v1
@@ -165,27 +129,12 @@ jobs:
     needs: ci-config
     if: needs.ci-config.outputs.enabled == 'yes'
     env:
-      MSYSTEM: MINGW64
       NO_PERL: 1
       GIT_CONFIG_PARAMETERS: "'user.name=CI' 'user.email=ci@git'"
     runs-on: windows-latest
     steps:
     - uses: actions/checkout@v1
-    - name: download git-sdk-64-minimal
-      shell: bash
-      run: |
-        ## Get artifact
-        urlbase=https://dev.azure.com/git-for-windows/git/_apis/build/builds
-        id=$(curl "$urlbase?definitions=22&statusFilter=completed&resultFilter=succeeded&\$top=1" |
-          jq -r ".value[] | .id")
-        download_url="$(curl "$urlbase/$id/artifacts" |
-          jq -r '.value[] | select(.name == "git-sdk-64-minimal").resource.downloadUrl')"
-        curl --connect-timeout 10 --retry 5 --retry-delay 0 --retry-max-time 240 \
-          -o artifacts.zip "$download_url"
-
-        ## Unzip and remove the artifact
-        unzip artifacts.zip
-        rm artifacts.zip
+    - uses: git-for-windows/setup-git-for-windows-sdk@v1
     - name: initialize vcpkg
       uses: actions/checkout@v2
       with:
@@ -211,38 +160,32 @@ jobs:
       shell: bash
       run: |
         cmake `pwd`/contrib/buildsystems/ -DCMAKE_PREFIX_PATH=`pwd`/compat/vcbuild/vcpkg/installed/x64-windows \
-        -DMSGFMT_EXE=`pwd`/git-sdk-64-minimal/mingw64/bin/msgfmt.exe -DPERL_TESTS=OFF -DPYTHON_TESTS=OFF -DCURL_NO_CURL_CMAKE=ON
+        -DMSGFMT_EXE=C:/git-sdk-64-minimal/mingw64/bin/msgfmt.exe -DPERL_TESTS=OFF -DPYTHON_TESTS=OFF -DCURL_NO_CURL_CMAKE=ON
     - name: MSBuild
       run: msbuild git.sln -property:Configuration=Release -property:Platform=x64 -maxCpuCount:4 -property:PlatformToolset=v142
     - name: bundle artifact tar
-      shell: powershell
+      shell: bash
       env:
         MSVC: 1
         VCPKG_ROOT: ${{github.workspace}}\compat\vcbuild\vcpkg
       run: |
-        & git-sdk-64-minimal\usr\bin\bash.exe -lc @"
-          mkdir -p artifacts &&
-          eval \"`$(make -n artifacts-tar INCLUDE_DLLS_IN_ARTIFACTS=YesPlease ARTIFACTS_DIRECTORY=artifacts 2>&1 | grep ^tar)\"
-        "@
+        mkdir -p artifacts &&
+        eval "$(make -n artifacts-tar INCLUDE_DLLS_IN_ARTIFACTS=YesPlease ARTIFACTS_DIRECTORY=artifacts 2>&1 | grep ^tar)"
     - name: upload build artifacts
       uses: actions/upload-artifact@v1
       with:
         name: vs-artifacts
         path: artifacts
   vs-test:
     runs-on: windows-latest
-    needs: [vs-build, windows-build]
+    needs: vs-build
     strategy:
       fail-fast: false
       matrix:
         nr: [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
     steps:
     - uses: actions/checkout@v1
-    - name: download git-sdk-64-minimal
-      uses: actions/download-artifact@v1
-      with:
-        name: git-sdk-64-minimal
-        path: ${{github.workspace}}/git-sdk-64-minimal/
+    - uses: git-for-windows/setup-git-for-windows-sdk@v1
     - name: download build artifacts
       uses: actions/download-artifact@v1
       with:
@@ -252,23 +195,15 @@ jobs:
       shell: bash
       run: tar xf artifacts.tar.gz
     - name: test
-      shell: powershell
+      shell: bash
       env:
-        MSYSTEM: MINGW64
         NO_SVN_TESTS: 1
         GIT_TEST_SKIP_REBASE_P: 1
-      run: |
-        & .\git-sdk-64-minimal\usr\bin\bash.exe -lc @"
-          # Let Git ignore the SDK and the test-cache
-          printf '%s\n' /git-sdk-64-minimal/ /test-cache/ >>.git/info/exclude
-
-          ci/run-test-slice.sh ${{matrix.nr}} 10
-        "@
+      run: ci/run-test-slice.sh ${{matrix.nr}} 10
     - name: ci/print-test-failures.sh
       if: failure()
-      shell: powershell
-      run: |
-        & .\git-sdk-64-minimal\usr\bin\bash.exe -lc ci/print-test-failures.sh
+      shell: bash
+      run: ci/print-test-failures.sh
     - name: Upload failed tests' directories
       if: failure() && env.FAILED_TEST_ARTIFACTS != ''
       uses: actions/upload-artifact@v1