Add InterpreterOptions e2e test (#262)

This new test ensures that the `InterpreterOptions` plugin config option
is being honoured by `python_binary` by changing the `__main__` module
that the Python interpreter is supposed to execute and checking that the
correct one is in fact executed.

Author: chrisnovakovic

test/BUILD

@@ -202,3 +202,14 @@ python_test(
     ],
     labels = ["manual"],
 )
+
+plugin_e2e_test(
+    name = "interpreter_options_test",
+    repo = "interpreter_options_repo",
+    test_cmd = [
+        "plz run //:binary > binary",
+    ],
+    expected_output = {
+        "binary": "Executed plzmodule.py",
+    },
+)

test/interpreter_options_repo/.plzconfig

@@ -0,0 +1,2 @@
+[Plugin "python"]
+Target = //plugins:python

test/interpreter_options_repo/BUILD_FILE

@@ -0,0 +1,16 @@
+subinclude("///python//build_defs:python")
+
+package(
+    # If InterpreterOptions is being honoured, the Python interpreter should execute plzmodule.py
+    # as the __main__ module instead of main.py, causing "Executed plzmodule.py" to be printed on
+    # stdout rather than "Executed binary.py".
+    python = {
+        "interpreter_options": ["-m", "plzmodule"],
+    },
+)
+
+python_binary(
+    name = "binary",
+    main = "binary.py",
+    srcs = ["plzmodule.py"],
+)

test/interpreter_options_repo/binary.py

@@ -0,0 +1,2 @@
+if __name__ == "__main__":
+    print("Executed binary.py")

test/interpreter_options_repo/plugins/BUILD_FILE

@@ -0,0 +1,4 @@
+plugin_repo(
+    name = "python",
+    revision = "e2e",
+)

test/interpreter_options_repo/plzmodule.py

@@ -0,0 +1,2 @@
+if __name__ == "__main__":
+    print("Executed plzmodule.py")