feat: add auto-precompile input to the reusable test workflows

.github/workflows/grouped-tests.yml

@@ -74,6 +74,11 @@ on:
         default: false
         required: false
         type: boolean
+      auto-precompile:
+        description: "Value of JULIA_PKG_PRECOMPILE_AUTO for each test job (true -> 1, false -> 0). Set false for packages whose dependency tree OOMs the runner during Pkg's eager parallel precompilation."
+        default: true
+        required: false
+        type: boolean
 
 jobs:
   detect:
@@ -123,4 +128,5 @@ jobs:
       apt-packages: "${{ inputs.apt-packages }}"
       container: "${{ inputs.container }}"
       cache: ${{ inputs.cache }}
+      auto-precompile: ${{ inputs.auto-precompile }}
     secrets: "inherit"

.github/workflows/sublibrary-project-tests.yml

@@ -66,6 +66,11 @@ on:
         default: false
         required: false
         type: boolean
+      auto-precompile:
+        description: "Value of JULIA_PKG_PRECOMPILE_AUTO for each sublibrary test job (true -> 1, false -> 0). Set false for sublibraries whose dependency tree OOMs the runner during Pkg's eager parallel precompilation."
+        default: true
+        required: false
+        type: boolean
 
 jobs:
   detect:
@@ -163,6 +168,7 @@ jobs:
       coverage: ${{ inputs.coverage }}
       coverage-directories: "${{ matrix.project }}/src,${{ matrix.project }}/ext"
       cache: ${{ inputs.cache }}
+      auto-precompile: ${{ inputs.auto-precompile }}
     secrets: "inherit"
 
   test-2:
@@ -187,6 +193,7 @@ jobs:
       coverage: ${{ inputs.coverage }}
       coverage-directories: "${{ matrix.project }}/src,${{ matrix.project }}/ext"
       cache: ${{ inputs.cache }}
+      auto-precompile: ${{ inputs.auto-precompile }}
     secrets: "inherit"
 
   test-3:
@@ -211,6 +218,7 @@ jobs:
       coverage: ${{ inputs.coverage }}
       coverage-directories: "${{ matrix.project }}/src,${{ matrix.project }}/ext"
       cache: ${{ inputs.cache }}
+      auto-precompile: ${{ inputs.auto-precompile }}
     secrets: "inherit"
 
   test-4:
@@ -235,4 +243,5 @@ jobs:
       coverage: ${{ inputs.coverage }}
       coverage-directories: "${{ matrix.project }}/src,${{ matrix.project }}/ext"
       cache: ${{ inputs.cache }}
+      auto-precompile: ${{ inputs.auto-precompile }}
     secrets: "inherit"

.github/workflows/tests.yml

@@ -106,6 +106,11 @@ on:
         default: false
         required: false
         type: boolean
+      auto-precompile:
+        description: "Value of JULIA_PKG_PRECOMPILE_AUTO for the whole job (true -> 1, false -> 0). Set false for packages whose dependency tree OOMs the runner during Pkg's eager parallel precompilation."
+        default: true
+        required: false
+        type: boolean
       dotgithub-ref:
         description: "Ref of SciML/.github to source the develop-sources helper script from"
         default: "v1"
@@ -126,6 +131,11 @@ jobs:
     runs-on: ${{ (inputs.apt-packages != '' || inputs.container != '') && fromJSON('["ubuntu-24.04"]') || (inputs.runner != '' && fromJson(inputs.runner) || (inputs.self-hosted && 'self-hosted' || inputs.os)) }}
     container: ${{ inputs.container }}
     timeout-minutes: ${{ inputs.timeout-minutes }}
+    env:
+      # Job-level so it covers buildpkg (instantiate/build) as well as the test
+      # run. A caller cannot set this at its own call site: a job that uses a
+      # reusable workflow may not carry an `env:` map, so it has to be an input.
+      JULIA_PKG_PRECOMPILE_AUTO: "${{ inputs.auto-precompile && '1' || '0' }}"
     steps:
       - uses: actions/checkout@v7
 

test/runtests.jl

@@ -600,3 +600,30 @@ end
     root = make_sources_fixture()
     @test isempty(collect_source_paths(joinpath(root, "Leaf")))
 end
+
+@testset "auto-precompile input is plumbed to JULIA_PKG_PRECOMPILE_AUTO" begin
+    wf(p) = read(joinpath(@__DIR__, "..", ".github", "workflows", p), String)
+
+    tests = wf("tests.yml")
+    # Declared as a boolean input, defaulting to Pkg's normal eager behavior.
+    @test occursin("auto-precompile:", tests)
+    # Job-level (not step-level) so buildpkg's instantiate/build is covered too.
+    precompile_at = findfirst("JULIA_PKG_PRECOMPILE_AUTO", tests)
+    steps_at = findfirst("\n    steps:", tests)
+    @test precompile_at !== nothing && steps_at !== nothing
+    @test first(precompile_at) < first(steps_at)
+    @test occursin("JULIA_PKG_PRECOMPILE_AUTO: \"\${{ inputs.auto-precompile && '1' || '0' }}\"", tests)
+
+    # Both fan-out workflows expose the input and forward it, or a caller has no
+    # way to set it: a job that `uses:` a reusable workflow may not carry `env:`.
+    for p in ("grouped-tests.yml", "sublibrary-project-tests.yml")
+        txt = wf(p)
+        @test occursin("auto-precompile:", txt)
+        @test occursin("auto-precompile: \${{ inputs.auto-precompile }}", txt)
+    end
+
+    # sublibrary-project-tests fans out over four shards; every one must forward
+    # it, otherwise the setting silently applies to only part of the matrix.
+    subs = wf("sublibrary-project-tests.yml")
+    @test count("auto-precompile: \${{ inputs.auto-precompile }}", subs) == 4
+end