Merge pull request #2737 from SciML/os/fix-downstream

fix downstream runners

Author: ChrisRackauckas

.github/workflows/Downstream.yml

@@ -49,6 +49,21 @@ jobs:
         with:
           repository: ${{ matrix.package.user }}/${{ matrix.package.repo }}
           path: downstream
+      - name: Load this and run the downstream tests
+        shell: julia --color=yes --project=downstream {0}
+        run: |
+          using Pkg
+          try
+            Pkg.develop(map(path ->Pkg.PackageSpec.(;path="lib/$(path)"), readdir("./lib")));
+            Pkg.test(coverage=true)  # resolver may fail with test time depsAdd commentMore actions
+          catch err
+            err isa Pkg.Resolve.ResolverError || rethrow()
+            # If we can't resolve that means this is incompatible by SemVer and this is fine
+            # It means we marked this as a breaking change, so we don't need to worry about
+            # mistakenly introducing a breaking change, as we have intentionally made one
+            @info "Not compatible with this release. No problem." exception=err
+            exit(0)  # Exit immediately, as a success
+          end
       - uses: julia-actions/julia-processcoverage@v1
       - uses: codecov/codecov-action@v5
         with: