enable python unit test

.gitignore

@@ -53,4 +53,5 @@ __pycache__/
 *.pyc
 *.opc
 /.test/
-docs/superpowers/
+docs/superpowers/
+ctest_results.xml

scripts/run_unit_tests.sh

@@ -17,6 +17,24 @@ cd "${ROOT_DIR}" || exit 1
 TEST_DIR="${1:-build/tests}"
 BUILD_CONFIG="${2:-}"
 
+# The slic3rutils plugin-host tests build numpy arrays through the CPython copied next
+# to the test binary (see tests/slic3rutils/CMakeLists.txt); that runtime ships pip but
+# no numpy, so those tests SKIP without it. Install it into that interpreter's own
+# site-packages -- no PYTHONPATH needed, and re-checked every run because a rebuild of
+# the test target wipes and re-copies the runtime. Needs network on the first run only;
+# a failure here is not fatal, the tests just keep skipping.
+find_args=("${TEST_DIR}" \( -path '*/python/bin/python3' -o -path '*/python/python.exe' \))
+# Multi-config trees hold one copy per configuration; only bootstrap the one being run.
+[ -n "${BUILD_CONFIG}" ] && find_args+=(-path "*/${BUILD_CONFIG}/*")
+python_exe="$(find "${find_args[@]}" -print -quit 2>/dev/null)"
+if [ -z "${python_exe}" ]; then
+    echo "No bundled Python under ${TEST_DIR}; numpy-backed binding tests will skip."
+elif ! "${python_exe}" -c "import numpy" >/dev/null 2>&1; then
+    echo "Installing numpy into the embedded test interpreter (${python_exe})..."
+    "${python_exe}" -m pip install --quiet --disable-pip-version-check --retries 1 "numpy<3" \
+        || echo "numpy install failed; numpy-backed binding tests will skip."
+fi
+
 # Run the whole suite, excluding tests tagged [NotWorking].
 # --no-tests=error fails the job if the filter matches nothing (instead of passing green).
 args=(--test-dir "${TEST_DIR}" -LE "NotWorking" --no-tests=error --output-junit "$(pwd)/ctest_results.xml" --output-on-failure -j)

src/slic3r/plugin/PythonInterpreter.cpp

@@ -345,16 +345,21 @@ boost::filesystem::path find_bundled_python_home()
     fs::path bundle_python = fs::path(resources_dir()).parent_path() / "MacOS" / "python";
     if (valid_python_home(bundle_python))
         return bundle_python;
-#elif defined(_WIN32)
-    fs::path exe_python = boost::dll::program_location().parent_path() / "python";
-    if (valid_python_home(exe_python))
-        return exe_python;
-#else
+#elif !defined(_WIN32)
     fs::path linux_python = fs::path(resources_dir()).parent_path() / "lib" / "python";
     if (valid_python_home(linux_python))
         return linux_python;
 #endif
 
+    // Next to the executable: the Windows install layout, and the runtime copied
+    // beside every platform's unit-test binary (tests/slic3rutils/CMakeLists.txt).
+    // The CI test runner only receives the build/tests tree, so the candidates
+    // below -- all of which point into the deps or install trees -- never resolve
+    // there.
+    fs::path exe_python = boost::dll::program_location().parent_path() / "python";
+    if (valid_python_home(exe_python))
+        return exe_python;
+
     fs::path configured_python = ORCA_BUNDLED_PYTHON_ROOT;
     if (!configured_python.empty() && valid_python_home(configured_python))
         return configured_python;

tests/slic3rutils/CMakeLists.txt

@@ -42,9 +42,16 @@ if (WIN32)
         COMMENT "Copying Python runtime for slic3rutils plugin host API tests"
         VERBATIM
     )
-elseif (APPLE)
-    target_link_options(${_TEST_NAME}_tests PRIVATE
-        "LINKER:-rpath,@executable_path/python/lib")
+else ()
+    # The CI unit-test runner only receives the build/tests tree, so both the
+    # interpreter and the libpython the test binary links have to travel next to
+    # the executable; find_bundled_python_home() picks the copy up from there.
+    if (APPLE)
+        target_link_options(${_TEST_NAME}_tests PRIVATE
+            "LINKER:-rpath,@executable_path/python/lib")
+    else ()
+        set_property(TARGET ${_TEST_NAME}_tests APPEND PROPERTY BUILD_RPATH "$ORIGIN/python/lib")
+    endif ()
 
     add_custom_command(TARGET ${_TEST_NAME}_tests POST_BUILD
         COMMAND ${CMAKE_COMMAND} -E rm -rf
@@ -52,7 +59,7 @@ elseif (APPLE)
         COMMAND ${CMAKE_COMMAND} -E copy_directory
             "${CMAKE_PREFIX_PATH}/libpython"
             "$<TARGET_FILE_DIR:${_TEST_NAME}_tests>/python"
-        COMMENT "Copying Python runtime for macOS plugin host API tests"
+        COMMENT "Copying Python runtime for the plugin host API tests"
         VERBATIM
     )
 endif()