Hack on per-commit build

.github/workflows/dev.yml

@@ -58,14 +58,14 @@ jobs:
               - '!(README.md|LICENSE|design-docs/**|.gitignore|.github/**)'
               - '.github/workflows/dev.yml'
 
-  history:
-    name: "Deduce required tests from code changes"
+  commits:
+    name: "Deduce commit history"
     permissions:
       contents: "read"
       pull-requests: "read"
     runs-on: "ubuntu-latest"
     outputs:
-      commits: "${{ steps.changes.outputs.commits }}"
+      commits: "${{ steps.commits.outputs.commits }}"
     steps:
       - name: "install jq"
         run: |
@@ -80,23 +80,23 @@ jobs:
       - name: "commits"
         id: "commits"
         run: |
-          git rev-list --reverse ${{ github.event.pull_request.base.sha }}..${{ github.event.pull_request.head.sha }} \
-            | jq --null-input --raw-input --raw-output --compact-output '[inputs] | "commits=(. | tostring)"' \
+          set -euxo pipefail
+          git rev-list --pretty=oneline ${{ github.event.pull_request.base.sha }}..${{ github.event.pull_request.head.sha }} \
+            | sed -e  's/ /", "msg": "/' -e 's/^/{"ref": "/' -e 's/$/"}/' \
+            | jq --null-input --raw-output --compact-output '[inputs] | "commits=" + (. | tostring)' \
             | tee -a "${GITHUB_OUTPUT}"
 
   build:
-    needs: [ check_changes, history ]
+    needs: [ check_changes, commits ]
     if: "${{ needs.check_changes.outputs.devfiles == 'true' }}"
     strategy:
       fail-fast: false
-      max-parallel: 4
       matrix:
-        commit: ${{ fromJSON(needs.history.outputs.commits) }}
+        commit: ${{ fromJSON(needs.commits.outputs.commits) }}
         rust:
           - "stable"
-          - "beta"
           - "nightly"
-    name: "Developer build (Rust ${{ matrix.rust }})"
+    name: "rust/${{ matrix.rust }}/${{ matrix.commit.msg }}"
     runs-on: "lab"
     timeout-minutes: 45
     steps:
@@ -111,12 +111,12 @@ jobs:
         with:
           toolchain: "${{ matrix.rust }}"
           targets: "x86_64-unknown-linux-gnu,x86_64-unknown-linux-musl"
-      - name: "Checkout"
+      - name: "Checkout ${{matrix.commit.msg}}"
         uses: "actions/checkout@v4"
         with:
-          ref: "${{ matrix.commit }}"
+          ref: "${{ matrix.commit.ref }}"
           persist-credentials: "false"
-          fetch-depth: "0"
+          fetch-depth: "1"
       - uses: "cargo-bins/cargo-binstall@main"
       - name: "install just"
         run: |
@@ -142,26 +142,6 @@ jobs:
       - run: |
           just --yes debug=true fake-nix
 
-#      - run: |
-#          # Run a simple build for each separate commit (for "pull_request")
-#          # or for the HEAD of the branch (other events).
-#          set -eu -o pipefail
-#          COMMITS=${{ github.sha }}
-#          if [[ "${{ github.event_name == 'pull_request' }}" == "true" ]]; then
-#            # Get all commits from Pull Request, in chronological order
-#            COMMITS=$(git rev-list --reverse ${{ github.event.pull_request.base.sha }}..${{ github.event.pull_request.head.sha }})
-#          fi
-#          for commit in $COMMITS ; do
-#            git checkout $commit || exit 1
-#            printf "::group::Build commit %s\n" "$(git log --oneline --no-decorate -n 1)"
-#            (just debug=true cargo +${{matrix.rust}} build --locked --profile=dev --target=x86_64-unknown-linux-gnu) || exit 1
-#            printf "::endgroup::\n"
-#          done
-#          printf "::notice::HEAD remains at %s\n" "$(git log --oneline --no-decorate -n 1)"
-#        continue-on-error: ${{ matrix.rust.optional }}
-
-      # At this stage, for Pull Requests, we're back to the HEAD of the branch,
-      # start running tests for different configurations.
       - name: "tests: rust ${{ matrix.rust }} profile=dev target=x86_64-unknown-linux-gnu"
         run: |
           export GITHUB_STEP_SUMMARY
@@ -195,7 +175,7 @@ jobs:
       - uses: "actions/upload-artifact@v4"
         if: ${{ always() }}
         with:
-          name: "test-results-${{ matrix.rust }}"
+          name: "results-${{ matrix.rust }}-${{ matrix.commit.ref }}"
           path: "target/nextest/"
 
       - name: "Setup tmate session for debug"