don't build PyCall in tests

instead, add a case to CI where we use system python for both, ensuring we test the same case. we also add tests for the non-same case.

Author: Christopher Doris

.github/workflows/tests.yml

@@ -12,14 +12,20 @@ on:
 
 jobs:
   julia:
-    name: Test Julia (${{ matrix.jlversion }}, ${{ matrix.os }})
+    name: Test Julia (${{ matrix.jlversion }}, ${{ matrix.os }}, ${{ matrix.pythonexe }})
     runs-on: ${{ matrix.os }}
     strategy:
       fail-fast: false
       matrix:
         arch: [x64] # x86 unsupported by MicroMamba
         os: [ubuntu-latest, windows-latest, macos-latest]
         jlversion: ['1','1.9']
+        python: ['@CondaPkg']
+        include:
+        - arch: x64
+          os: ubuntu-latest
+          jlversion: '1'
+          pythonexe: python
 
     steps:
       - uses: actions/checkout@v5
@@ -34,12 +40,16 @@ jobs:
 
       - name: Build package
         uses: julia-actions/julia-buildpkg@v1
+        env:
+          PYTHON: python
 
       - name: Run tests
         uses: julia-actions/julia-runtest@v1
         env:
           JULIA_DEBUG: PythonCall
           JULIA_NUM_THREADS: '2'
+          PYTHON: python
+          JULIA_PYTHONCALL_EXE: ${{ matrix.pythonexe }}
 
       - name: Process coverage
         uses: julia-actions/julia-processcoverage@v1

test/Compat.jl

@@ -38,12 +38,25 @@ end
     # TODO
 end
 
-@testitem "PyCall.jl" setup = [PyCall] begin
-    @test Base.get_extension(PythonCall, :PyCallExt).SAME[]
-    x1 = pylist()
-    x2 = PyCall.PyObject(x1)
-    x3 = Py(x2)
-    @test pyis(x3, x1)
+@testitem "PyCall.jl" begin
+    using PyCall
+    same = Base.get_extension(PythonCall, :PyCallExt).SAME[]::Bool
+    @info "testing PyCall" same
+    if get(ENV, "CI", "") != ""
+        # ensure we test both `same` and `!same` in CI
+        @test same == (ENV["JULIA_PYTHONCALL_EXE"] == "python")
+    end
+    if same
+        x1 = pylist()::Py
+        x2 = PyCall.PyObject(x1)::PyCall.PyObject
+        x3 = Py(x2)::Py
+        @test pyis(x3, x1)
+    else
+        x1 = pylist()::Py
+        @test_throws "only possible when using the same Python" PyCall.PyObject(x1)
+        x2 = PyCall.pybuiltin("list")()::PyCall.PyObject
+        @test_throws "only possible when using the same Python" Py(x2)
+    end
 end
 
 @testitem "Serialization.jl" begin

test/runtests.jl

@@ -1,12 +1,3 @@
 using TestItemRunner
 
 @run_package_tests
-
-@testmodule PyCall begin
-    using PythonCall: PythonCall
-    using Pkg: Pkg
-    ENV["PYTHON"] = PythonCall.python_executable_path()
-    @info "Building PyCall..." ENV["PYTHON"]
-    Pkg.build("PyCall")
-    using PyCall
-end