Release: promote develop to main (IGNORE_GITHUB_REF prerelease fix)

.github/workflows/build-release-task.yml

@@ -65,8 +65,16 @@ jobs:
         env:
           SEMVER2: ${{ needs.get-version.outputs.SemVer2 }}
           BRANCH: ${{ inputs.branch }}
+          SMOKE: ${{ inputs.smoke }}
         run: |
           set -euo pipefail
+          # This gate guards real publishes. A smoke build checks out the PR head in detached HEAD, so NBGV always
+          # yields a prerelease version; on a main-base PR that would trip the public-release check and fail every
+          # develop->main promotion that carries a build target. Skip the gate for smoke builds (they never publish).
+          if [[ "$SMOKE" == "true" ]]; then
+            echo "Smoke build; skipping release version validation."
+            exit 0
+          fi
           CORE_AND_PRE="${SEMVER2%%+*}"
           if [[ "$BRANCH" == "main" ]]; then
             if [[ "$CORE_AND_PRE" == *-* ]]; then

.github/workflows/get-version-task.yml

@@ -9,8 +9,9 @@ on:
         required: false
         type: string
         default: ''
-      # Logical branch NBGV classifies against. Pins PublicRelease to this branch instead of the runner's GITHUB_REF,
-      # which on a publish dispatched from the default branch is that branch for every matrix leg. Empty keeps GITHUB_REF.
+      # Logical branch NBGV classifies public-vs-prerelease against. With IGNORE_GITHUB_REF, NBGV reads the
+      # checked-out git branch; callers that check out a pinned commit (detached HEAD - the build jobs) pass this
+      # so a local branch can be created at that commit, giving NBGV the right name. Empty leaves the checkout as-is.
       branch:
         required: false
         type: string
@@ -53,13 +54,24 @@ jobs:
           ref: ${{ inputs.ref }}
           fetch-depth: 0
 
+      # NBGV (with IGNORE_GITHUB_REF) classifies public-vs-prerelease from the checked-out branch. A pinned-SHA
+      # checkout is detached HEAD, where NBGV sees no branch and treats every leg as prerelease (the main leg would
+      # then build a prerelease package mismatching its clean release tag). Force a local branch at HEAD matching the
+      # logical branch so NBGV sees the right name while still versioning the intended commit.
+      - name: Pin logical branch step
+        if: ${{ inputs.branch != '' }}
+        env:
+          BRANCH: ${{ inputs.branch }}
+        run: git checkout -B "$BRANCH"
+
       # nbgv is floated on @master: its tag stream lags master, so Dependabot tag-tracking would propose a downgrade.
       # Revisit if dotnet/nbgv resumes regular tagged releases.
       - name: Run Nerdbank.GitVersioning tool step
         id: nbgv
         uses: dotnet/nbgv@master
         env:
-          # NBGV reads the branch from GITHUB_REF; pin it to the leg being versioned so a publish dispatched from the
-          # default branch doesn't classify every leg as the public ref and strip its prerelease suffix.
-          GITHUB_REF: ${{ inputs.branch != '' && format('refs/heads/{0}', inputs.branch) || github.ref }}
-          GITHUB_REF_NAME: ${{ inputs.branch != '' && inputs.branch || github.ref_name }}
+          # NBGV's GitHub Actions cloud-build provider overrides the checked-out branch with GITHUB_REF (the dispatch
+          # ref). On a publish dispatched from the default branch that misclassifies every matrix leg as the public ref
+          # and strips the prerelease suffix. GITHUB_REF is reserved and cannot be reliably overridden, so tell NBGV to
+          # ignore it and version from the actually-checked-out branch (each leg checks out its own branch).
+          IGNORE_GITHUB_REF: true