setuptools_wrap: Fix support for py_modules and add test_py_modules_keyword

Similarly to what is done for scripts, this commit introduces
the ivar 'new_py_modules' to keep track of which module is installed
by a CMake install rule and which one is provided by the source tree.

This commit fixes the following test:

  tests/test_setup.py::test_py_modules_keyword[skbuild]

Author: jcfr

skbuild/setuptools_wrap.py

@@ -249,6 +249,7 @@ def setup(*args, **kw):
     package_data = kw.get('package_data', {}).copy()
 
     py_modules = kw.get('py_modules', [])
+    new_py_modules = {py_module: False for py_module in py_modules}
 
     scripts = kw.get('scripts', [])
     new_scripts = {script: False for script in scripts}
@@ -278,8 +279,10 @@ def setup(*args, **kw):
 
     package_prefixes = _collect_package_prefixes(package_dir, packages)
 
-    _classify_files(cmkr.install(), package_data, package_prefixes, py_modules,
-                    scripts, new_scripts, data_files)
+    _classify_files(cmkr.install(), package_data, package_prefixes,
+                    py_modules, new_py_modules,
+                    scripts, new_scripts,
+                    data_files)
 
     kw['package_data'] = package_data
     kw['package_dir'] = {
@@ -290,7 +293,10 @@ def setup(*args, **kw):
         for prefix, package in package_prefixes
     }
 
-    kw['py_modules'] = py_modules
+    kw['py_modules'] = [
+        os.path.join(cmaker.CMAKE_INSTALL_DIR, py_module) if mask else py_module
+        for py_module, mask in new_py_modules.items()
+    ]
 
     kw['scripts'] = [
         os.path.join(cmaker.CMAKE_INSTALL_DIR, script) if mask else script
@@ -353,8 +359,10 @@ def _collect_package_prefixes(package_dir, packages):
     ))
 
 
-def _classify_files(install_paths, package_data, package_prefixes, py_modules,
-                    scripts, new_scripts, data_files):
+def _classify_files(install_paths, package_data, package_prefixes,
+                    py_modules, new_py_modules,
+                    scripts, new_scripts,
+                    data_files):
     install_root = os.path.join(os.getcwd(), cmaker.CMAKE_INSTALL_DIR)
     for path in install_paths:
         found_package = False
@@ -394,6 +402,7 @@ def _classify_files(install_paths, package_data, package_prefixes, py_modules,
         # check if path is a module
         for module in py_modules:
             if path.replace("/", ".") == ".".join((module, "py")):
+                new_py_modules[module] = True
                 found_module = True
                 break
 

tests/test_setup.py

@@ -240,3 +240,47 @@ def test_script_keyword(distribution_type, capsys):
 
     out, _ = capsys.readouterr()
     assert message in out
+
+
+@pytest.mark.parametrize("distribution_type", ('pure', 'skbuild'))
+def test_py_modules_keyword(distribution_type, capsys):
+    tmp_dir = _tmpdir('py_modules_keyword')
+
+    tmp_dir.join('setup.py').write(textwrap.dedent(
+        """
+        from skbuild import setup
+        setup(
+            name="test_py_modules_keyword",
+            version="1.2.3",
+            description="a package testing use of py_modules keyword",
+            author='The scikit-build team',
+            license="MIT",
+            py_modules=['foo']
+        )
+        """
+    ))
+
+    if distribution_type == 'skbuild':
+        tmp_dir.join('CMakeLists.txt').write(textwrap.dedent(
+            """
+            cmake_minimum_required(VERSION 3.5.0)
+            project(foo)
+            file(WRITE "${CMAKE_BINARY_DIR}/foo.py" "# foo.py")
+            install(FILES "${CMAKE_BINARY_DIR}/foo.py" DESTINATION ".")
+            """
+        ))
+
+        message = "copying _skbuild/cmake-install/foo.py -> " \
+                  "_skbuild/setuptools/lib".replace("/", os.path.sep)
+
+    elif distribution_type == 'pure':
+        tmp_dir.join('foo.py').write("# foo.py")
+
+        message = "copying foo.py -> " \
+                  "_skbuild/setuptools/lib".replace("/", os.path.sep)
+
+    with execute_setup_py(tmp_dir, ['build']):
+        pass
+
+    out, _ = capsys.readouterr()
+    assert message in out