Make __init__.py files creation optional

Introduce a new attribute to py_binary and py_test to control whether to
create `__init__.py` or not.

Fixes https://github.com/bazelbuild/rules_python/issues/55

Closes #4470.

PiperOrigin-RevId: 185672243

1 files changed, 41 insertions, 0 deletions

diff --git a/src/test/py/bazel/py_test.py b/src/test/py/bazel/py_test.py
index 26fe88a0d6..3d97e79105 100644
--- a/src/test/py/bazel/py_test.py
+++ b/src/test/py/bazel/py_test.py
@@ -65,5 +65,46 @@ class PyTest(test_base.TestBase):
                     .endswith('/a/b.py'))
 
 
+class TestInitPyFiles(test_base.TestBase):
+
+  def createSimpleFiles(self, create_init=True):
+    self.ScratchFile('WORKSPACE')
+
+    self.ScratchFile('src/a/BUILD', [
+        'py_binary(name="a", srcs=["a.py"], deps=[":b"], legacy_create_init=%s)'
+        % create_init,
+        'py_library(name="b", srcs=["b.py"])',
+    ])
+
+    self.ScratchFile('src/a/a.py', [
+        'from src.a import b',
+        'b.Hello()',
+    ])
+
+    self.ScratchFile('src/a/b.py', [
+        'def Hello():',
+        '    print("Hello, World")',
+    ])
+
+  def testInitPyFilesCreated(self):
+    self.createSimpleFiles()
+    exit_code, _, stderr = self.RunBazel(['build', '//src/a:a'])
+    self.AssertExitCode(exit_code, 0, stderr)
+    self.assertTrue(
+        os.path.exists('bazel-bin/src/a/a.runfiles/__main__/src/__init__.py'))
+    self.assertTrue(
+        os.path.exists('bazel-bin/src/a/a.runfiles/__main__/src/a/__init__.py'))
+
+
+def testInitPyFilesNotCreatedWhenLegacyCreateInitIsSet(self):
+  self.createSimpleFiles(create_init=False)
+  exit_code, _, stderr = self.RunBazel(['build', '//src/a:a'])
+  self.AssertExitCode(exit_code, 0, stderr)
+  self.assertFalse(
+      os.path.exists('bazel-bin/src/a/a.runfiles/__main__/src/__init__.py'))
+  self.assertFalse(
+      os.path.exists('bazel-bin/src/a/a.runfiles/__main__/src/a/__init__.py'))
+
+
 if __name__ == '__main__':
   unittest.main()