Update export CI to test ETACE models, remove outdated ACEModel tests

- Update runtests.jl to only include ETACE-based tests:
  - etace: ETACE polynomial export tests
  - hermite: Hermite spline export tests
  - multispecies: Multi-species model tests
  - python, lammps, mpi: Integration tests

- Update export-ci.yml:
  - Rename test-export to test-etace-export
  - Run etace, hermite, multispecies tests
  - Add juliac compilation step to produce library artifact
  - Add ACE registry for dependency resolution

- Remove outdated test files that used ACEModel (not ETACE):
  - test_export.jl
  - test_c_interface_minimal.jl
  - test_minimal_export.jl
  - test_portable_python.jl

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <[email protected]>

Author: jameskermode

.github/workflows/export-ci.yml

@@ -78,7 +78,8 @@ jobs:
             lammps/src/nlohmann/
           retention-days: 1
 
-  test-export:
+  test-etace-export:
+    name: ETACE Export Tests
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
@@ -89,6 +90,10 @@ jobs:
         with:
           version: '1.12'
 
+      - name: Add ACE registry
+        run: |
+          julia -e 'using Pkg; Pkg.Registry.add(RegistrySpec(url="https://github.com/ACEsuit/ACEregistry"))'
+
       - name: Cache Julia packages
         uses: actions/cache@v4
         with:
@@ -108,9 +113,59 @@ jobs:
             Pkg.precompile()
           '
 
-      - name: Run Julia export tests
+      - name: Run ETACE export tests (polynomial, hermite, multispecies)
+        run: |
+          julia --project=export export/test/runtests.jl etace hermite multispecies
+
+      - name: Compile ETACE model to shared library
         run: |
-          julia --project=export export/test/runtests.jl export
+          # Use one of the exported models from the tests
+          cd export/test/build
+          MODEL_FILE=$(ls test_etace_*.jl 2>/dev/null | head -1)
+          if [ -z "$MODEL_FILE" ]; then
+            echo "No exported model found, creating one..."
+            julia --project=../../ -e '
+              include("../../src/export_ace_model.jl")
+              using ACEpotentials
+              using ACEpotentials.Models
+              using ACEpotentials.ETModels
+              using Lux, LuxCore, Random
+
+              # Create minimal ETACE model for testing
+              elements = (:Si,)
+              rcut = 5.5
+              rin0cuts = Models._default_rin0cuts(elements)
+              rin0cuts = (x -> (rin = x.rin, r0 = x.r0, rcut = rcut)).(rin0cuts)
+
+              ace_model = Models.ace_model(;
+                  elements = elements, order = 2, Ytype = :solid,
+                  level = Models.TotalDegree(), max_level = 6, maxl = 2,
+                  pair_maxn = 6, rin0cuts = rin0cuts,
+                  init_WB = :glorot_normal, init_Wpair = :glorot_normal
+              )
+              ps, st = Lux.setup(Random.MersenneTwister(1234), ace_model)
+
+              et_model = ETModels.convert2et(ace_model)
+              et_ps, et_st = LuxCore.setup(Random.MersenneTwister(1234), et_model)
+
+              # Copy parameters
+              et_ps.rembed.post.W[:, :, 1] .= ps.rbasis.Wnlq[:, :, 1, 1]
+              et_ps.readout.W[1, :, 1] .= ps.WB[:, 1]
+
+              et_calc = ETModels.ETACEPotential(et_model, et_ps, et_st, rcut)
+              export_ace_model(et_calc, "test_etace_model.jl"; for_library=true)
+            '
+            MODEL_FILE="test_etace_model.jl"
+          fi
+          echo "Compiling $MODEL_FILE..."
+
+          # Use juliac to compile
+          JULIAC_SCRIPT=$(julia -e 'print(joinpath(Sys.BINDIR, "..", "share", "julia", "juliac.jl"))')
+          julia --startup-file=no -C generic --project=../../ "$JULIAC_SCRIPT" \
+            --experimental --compile-ccallable \
+            --output-lib libace_test.so --trim=safe "$MODEL_FILE"
+
+          ls -la libace_test.so
 
       - name: Upload compiled library
         uses: actions/upload-artifact@v4
@@ -121,7 +176,7 @@ jobs:
 
   test-python:
     runs-on: ubuntu-latest
-    needs: test-export
+    needs: test-etace-export
     steps:
       - name: Checkout
         uses: actions/checkout@v4
@@ -178,7 +233,7 @@ jobs:
 
   test-lammps-serial:
     runs-on: ubuntu-latest
-    needs: [build-lammps, test-export]
+    needs: [build-lammps, test-etace-export]
     steps:
       - name: Checkout
         uses: actions/checkout@v4
@@ -340,7 +395,7 @@ jobs:
   test-ase-ace-library:
     name: ase-ace (library calculator)
     runs-on: ubuntu-latest
-    needs: test-export
+    needs: test-etace-export
     steps:
       - name: Checkout
         uses: actions/checkout@v4
@@ -399,7 +454,7 @@ jobs:
   test-ase-ace-julia:
     name: ase-ace (julia calculator)
     runs-on: ubuntu-latest
-    needs: test-export
+    needs: test-etace-export
     steps:
       - name: Checkout
         uses: actions/checkout@v4

export/test/runtests.jl

@@ -1,23 +1,22 @@
 #=
 Export Test Suite - Main Test Runner
 
-This file orchestrates all export-related tests:
-1. Julia export functionality (model export, compilation, evaluation)
-2. ETACE export functionality (ETACE model export with solid harmonics)
-3. Python calculator integration
-4. LAMMPS plugin integration (serial)
-5. Multi-species model tests
+This file orchestrates all export-related tests for ETACE models:
+1. ETACE export functionality (polynomial radial basis)
+2. Hermite spline export (machine-precision splined radial basis)
+3. Multi-species model tests
+4. Python calculator integration
+5. LAMMPS plugin integration (serial)
 6. MPI parallel tests
 
 Usage:
     julia --project=.. runtests.jl              # Run all available tests
-    julia --project=.. runtests.jl export       # Run only ACEModel export tests
-    julia --project=.. runtests.jl etace        # Run only ETACE export tests
-    julia --project=.. runtests.jl python       # Run only Python tests
-    julia --project=.. runtests.jl portable     # Run only portable Python tests
-    julia --project=.. runtests.jl lammps       # Run only LAMMPS tests
-    julia --project=.. runtests.jl multispecies # Run only multi-species tests
-    julia --project=.. runtests.jl mpi          # Run only MPI tests
+    julia --project=.. runtests.jl etace        # Run ETACE polynomial export tests
+    julia --project=.. runtests.jl hermite      # Run Hermite spline export tests
+    julia --project=.. runtests.jl multispecies # Run multi-species tests
+    julia --project=.. runtests.jl python       # Run Python tests
+    julia --project=.. runtests.jl lammps       # Run LAMMPS tests
+    julia --project=.. runtests.jl mpi          # Run MPI tests
 =#
 
 using Test
@@ -36,59 +35,6 @@ const PROJECT_DIR = dirname(EXPORT_DIR)
 # Global test artifacts (created once, reused across tests)
 const TEST_ARTIFACTS = Dict{String, Any}()
 
-"""
-    setup_test_model()
-
-Fit a small Si model for testing. Returns (potential, test_data).
-Caches the result for reuse across test files.
-"""
-function setup_test_model()
-    if haskey(TEST_ARTIFACTS, "potential")
-        return TEST_ARTIFACTS["potential"], TEST_ARTIFACTS["test_data"]
-    end
-
-    @info "Setting up test model (fitting Si potential)..."
-
-    # Load training data using example_dataset
-    dataset = ACEpotentials.example_dataset("Si_tiny")
-    data = dataset.train
-
-    # Create small model for fast testing
-    model = ACEpotentials.ace1_model(
-        elements = [:Si],
-        order = 2,
-        totaldegree = 6,
-        rcut = 5.5,
-    )
-
-    # Data keys matching Si_tiny dataset
-    data_keys = (
-        energy_key = "dft_energy",
-        force_key = "dft_force",
-        virial_key = "dft_virial",
-    )
-
-    weights = Dict("default" => Dict("E" => 30.0, "F" => 1.0, "V" => 1.0))
-
-    # Fit model
-    ACEpotentials.acefit!(data, model;
-        data_keys...,
-        weights = weights,
-        solver = ACEfit.BLR(),
-    )
-
-    # Get the fitted potential
-    potential = model
-
-    # Store for reuse
-    TEST_ARTIFACTS["potential"] = potential
-    TEST_ARTIFACTS["test_data"] = data
-
-    @info "Test model ready"
-
-    return potential, data
-end
-
 """
     get_test_structure()
 
@@ -160,58 +106,6 @@ function check_mpi_available()
     end
 end
 
-"""
-    get_compiled_library()
-
-Get path to compiled test library. Compiles if not exists.
-"""
-function get_compiled_library()
-    if haskey(TEST_ARTIFACTS, "lib_path")
-        return TEST_ARTIFACTS["lib_path"]
-    end
-
-    # Set up model first
-    potential, _ = setup_test_model()
-
-    # Export and compile
-    build_dir = joinpath(TEST_DIR, "build")
-    mkpath(build_dir)
-
-    @info "Exporting model to Julia code..."
-    include(joinpath(EXPORT_DIR, "src", "export_ace_model.jl"))
-    model_file = joinpath(build_dir, "test_ace_model.jl")
-    export_ace_model(potential, model_file; for_library=true)
-
-    @info "Compiling to shared library..."
-    lib_path = joinpath(build_dir, "libace_test.so")
-
-    # Run juliac
-    juliac_cmd = `julia --project=$(EXPORT_DIR) -e "
-        using PackageCompiler
-        PackageCompiler.juliac(
-            \"$(model_file)\",
-            \"$(lib_path)\";
-            compile_library=true,
-            trim=true,
-            verbose=true
-        )
-    "`
-
-    # Alternative: use juliac directly if available
-    # juliac_cmd = `juliac --output-lib $(lib_path) --trim=safe --project=$(EXPORT_DIR) $(model_file)`
-
-    run(juliac_cmd)
-
-    if !isfile(lib_path)
-        error("Compilation failed: $lib_path not created")
-    end
-
-    TEST_ARTIFACTS["lib_path"] = lib_path
-    TEST_ARTIFACTS["model_file"] = model_file
-
-    return lib_path
-end
-
 # Parse command line args for selective testing
 function get_test_selection()
     if length(ARGS) == 0
@@ -229,27 +123,33 @@ end
 function main()
     selection = get_test_selection()
 
-    @info "ACE Export Test Suite"
-    @info "====================="
+    @info "ACE Export Test Suite (ETACE)"
+    @info "=============================="
     @info "Test selection: $selection"
     @info "Python available: $(check_python_available())"
     @info "LAMMPS available: $(check_lammps_available())"
     @info "MPI available: $(check_mpi_available())"
     @info ""
 
     @testset "ACE Export Tests" verbose=true begin
-        # Julia export tests (ACEModel)
-        if should_run_test(selection, :export) || should_run_test(selection, :all)
-            @info "Running Julia export tests (ACEModel)..."
-            include(joinpath(TEST_DIR, "test_export.jl"))
-        end
-
-        # ETACE export tests
+        # ETACE export tests (polynomial radial basis)
         if should_run_test(selection, :etace) || should_run_test(selection, :all)
-            @info "Running ETACE export tests..."
+            @info "Running ETACE export tests (polynomial)..."
             include(joinpath(TEST_DIR, "test_etace_export.jl"))
         end
 
+        # Hermite spline export tests
+        if should_run_test(selection, :hermite) || should_run_test(selection, :all)
+            @info "Running Hermite spline export tests..."
+            include(joinpath(TEST_DIR, "test_hermite_spline_export.jl"))
+        end
+
+        # Multi-species tests
+        if should_run_test(selection, :multispecies) || should_run_test(selection, :all)
+            @info "Running multi-species export tests..."
+            include(joinpath(TEST_DIR, "test_multispecies.jl"))
+        end
+
         # Python tests
         if should_run_test(selection, :python) || should_run_test(selection, :all)
             if check_python_available()
@@ -260,16 +160,6 @@ function main()
             end
         end
 
-        # Portable Python tests (validates relocatable deployment)
-        if should_run_test(selection, :portable) || should_run_test(selection, :all)
-            if check_python_available()
-                @info "Running portable Python tests..."
-                include(joinpath(TEST_DIR, "test_portable_python.jl"))
-            else
-                @warn "Skipping portable Python tests (Python/numpy/ase not available)"
-            end
-        end
-
         # LAMMPS tests (serial)
         if should_run_test(selection, :lammps) || should_run_test(selection, :all)
             if check_lammps_available()
@@ -280,12 +170,6 @@ function main()
             end
         end
 
-        # Multi-species tests
-        if should_run_test(selection, :multispecies) || should_run_test(selection, :all)
-            @info "Running multi-species export tests..."
-            include(joinpath(TEST_DIR, "test_multispecies.jl"))
-        end
-
         # MPI tests
         if should_run_test(selection, :mpi) || should_run_test(selection, :all)
             if check_mpi_available() && check_lammps_available()