Fix editable installs with extension modules (#633)

Co-authored-by: Matthew Wardrop <mpwardrop@gmail.com>

src/poetry/core/masonry/builders/wheel.py

@@ -182,6 +182,11 @@ def _build(self, wheel: zipfile.ZipFile) -> None:
                     finally:
                         os.chdir(current_path)
 
+                    if self._editable:
+                        # For an editable install, the extension modules will be built
+                        # in-place - so there's no need to copy them into the zip
+                        return
+
                     build_dir = self._path / "build"
                     libs: list[Path] = list(build_dir.glob("lib.*"))
                     if not libs:
@@ -216,6 +221,15 @@ def _copy_file_scripts(self, wheel: zipfile.ZipFile) -> None:
             )
 
     def _run_build_command(self, setup: Path) -> None:
+        if self._editable:
+            subprocess.check_call(
+                [
+                    self.executable.as_posix(),
+                    str(setup),
+                    "build_ext",
+                    "--inplace",
+                ]
+            )
         subprocess.check_call(
             [
                 self.executable.as_posix(),

tests/masonry/builders/test_wheel.py

@@ -1,5 +1,6 @@
 from __future__ import annotations
 
+import importlib.machinery
 import os
 import re
 import shutil
@@ -28,13 +29,18 @@
 WHEEL_TAG_REGEX = "[cp]p[23]_?\\d+-(?:cp[23]_?\\d+m?u?|pypy[23]_?\\d+_pp\\d+)-.+"
 
 
+shared_lib_extensions = importlib.machinery.EXTENSION_SUFFIXES
+
+
 @pytest.fixture(autouse=True)
 def setup() -> Iterator[None]:
     clear_samples_dist()
+    clear_samples_build()
 
     yield
 
     clear_samples_dist()
+    clear_samples_build()
 
 
 def clear_samples_dist() -> None:
@@ -43,6 +49,15 @@ def clear_samples_dist() -> None:
             shutil.rmtree(str(dist))
 
 
+def clear_samples_build() -> None:
+    for build in fixtures_dir.glob("**/build"):
+        if build.is_dir():
+            shutil.rmtree(str(build))
+    for suffix in shared_lib_extensions:
+        for shared_lib in fixtures_dir.glob(f"**/*{suffix}"):
+            shared_lib.unlink()
+
+
 def test_wheel_module() -> None:
     module_path = fixtures_dir / "module1"
     WheelBuilder.make(Factory().create_poetry(module_path))
@@ -373,3 +388,32 @@ def test_tag(in_venv_build: bool, mocker: MockerFixture) -> None:
         get_sys_tags_spy.assert_not_called()
     else:
         get_sys_tags_spy.assert_called()
+
+
+def test_extended_editable_wheel_build() -> None:
+    """Tests that an editable wheel made from a project with extensions includes
+    the .pth, but does not include the built package itself.
+    """
+    root = fixtures_dir / "extended"
+    WheelBuilder.make_in(Factory().create_poetry(root), editable=True)
+
+    whl = next((root / "dist").glob("extended-0.1-*.whl"))
+
+    assert whl.exists()
+    with zipfile.ZipFile(str(whl)) as z:
+        assert "extended.pth" in z.namelist()
+        # Ensure the directory "extended/" does not exist in the whl
+        assert all(not n.startswith("extended/") for n in z.namelist())
+
+
+def test_extended_editable_build_inplace() -> None:
+    """Tests that a project with extensions builds the extension modules in-place
+    when ran for an editable install.
+    """
+    root = fixtures_dir / "extended"
+    WheelBuilder.make_in(Factory().create_poetry(root), editable=True)
+
+    # Check that an extension with any of the allowed extensions was built in-place
+    assert any(
+        (root / "extended" / f"extended{ext}").exists() for ext in shared_lib_extensions
+    )