Remove stale "pants.pex for integration tests" mechanism (pantsbuild#…

…10279)

### Problem

Since pantsbuild#8265, we have been running `PantsRunIntegrationTest`s from loose sources in the repository, which are included via `src/python/pants/testutil:int-test`'s dependency on `src/python/pants/bin:pants_local_binary`. That change thus removed the need for the `pants.pex` from our wrapper scripts.

### Solution

Remove the "`pants.pex` for integration tests" mechanism. Post pantsbuild#8625, pants is run from the PYTHONPATH of the test target, which will automatically include either loose sources or a `pants_requirement` target, depending on whether the test is run in or out of the pantsbuild/pants repo.

Additionally, remove one set of tests that was attempting to test that nested runs of pants do not deadlock. pantsbuild#7654 will eventually allow that issue to be resolved by allowing the concurrent run rather than via any sort of automatic disabling of `pantsd`, and that is much easier to test via concurrent runs _without_ nesting.

[ci skip-rust-tests]

BUILD

@@ -32,10 +32,3 @@ files(
   name = 'pyproject',
   sources = ['pyproject.toml'],
 )
-
-# NB: This is used for integration tests. This is generated automatically via `./pants` and
-# `build-support/bin/bootstrap_pants_pex.sh`.
-files(
-  name = 'pants_pex',
-  sources = ['pants.pex'],
-)

pants

@@ -106,27 +106,4 @@ else
   export PANTS_DEV=1
 fi
 
-# Integration tests depend on an up-to-date `pants.pex`. Here, we check if we're running tests
-# and ensure the `pants.pex` is generated if so. We do this here, rather than via `pants-plugins`,
-# because we want the file to be generated _before_ any tests run, not during that Pants invocation,
-# as the dependency is marked via BUILD files so should not be constructed at runtime.
-#
-# Note that we have no way to distinguish between integration tests vs unit tests here, so we
-# unfortunately rebuild the pants.pex for unit tests too.
-#
-# We do not do this when in CI because CI downloads the PEX from AWS and we never want a worker
-# shard to try bootstrapping the PEX itself.
-test_goal_used=false
-for arg in "$@"; do
-  if [[ "${arg}" == 'test' || "${arg}" == 'test.*' ]]; then
-    test_goal_used=true
-  fi
-done
-
-no_regen_pex="${NO_REGEN_PEX:-${TRAVIS}}"
-if [[ "${test_goal_used}" == 'true' && "${no_regen_pex}" != 'true' ]]; then
-  "$HERE/build-support/bin/bootstrap_pants_pex.sh"
-  echo -e "Finished bootstrapping pants.pex for integration tests.\n" >&2
-fi
-
 exec_pants_bare "$@"

src/python/pants/testutil/BUILD

@@ -25,7 +25,6 @@ python_library(
   sources = ['pants_run_integration_test.py'],
   dependencies = [
     '//:build_root',
-    '//:pants_pex',
     '3rdparty/python:ansicolors',
     '3rdparty/python:dataclasses',
     'src/python/pants/base:build_environment',

testprojects/src/python/BUILD

@@ -9,7 +9,6 @@ target(
     ':build_file_imports_module_directory',
     ':coordinated_runs_directory',
     ':interpreter_selection_directory',
-    ':nested_runs_directory',
     ':no_build_file_directory',
     ':plugins_directory',
     ':print_env_directory',
@@ -44,11 +43,6 @@ files(
   sources = ['interpreter_selection/**/*'],
 )
 
-files(
-  name = 'nested_runs_directory',
-  sources = ['nested_runs/**/*'],
-)
-
 files(
   name = 'no_build_file_directory',
   sources = ['no_build_file/**/*'],

tests/python/pants_test/bin/BUILD

@@ -9,7 +9,6 @@ python_tests(
     'src/python/pants/option',
     'src/python/pants/testutil:int-test',
     'testprojects:pants_plugins_directory',
-    'testprojects/src/python:nested_runs_directory',
   ],
   tags = ['integration'],
   timeout = 120,

tests/python/pants_test/bin/test_runner_integration.py

@@ -1,7 +1,6 @@
 # Copyright 2019 Pants project contributors (see CONTRIBUTORS.md).
 # Licensed under the Apache License, Version 2.0 (see LICENSE).
 
-import os
 from pathlib import Path
 
 from pants.base.build_environment import get_buildroot
@@ -42,33 +41,3 @@ def test_warning_filter(self):
         )
         self.assert_success(non_warning_run)
         self.assertNotIn("test warning", non_warning_run.stderr_data)
-
-    def test_parent_build_id_set_only_for_pants_runs_called_by_other_pants_runs(self):
-        with self.temporary_workdir() as workdir:
-            command = [
-                "run",
-                "testprojects/src/python/nested_runs",
-                "--",
-                workdir,
-            ]
-            result = self.run_pants_with_workdir(command, workdir,)
-            self.assert_success(result)
-
-            run_tracker_dir = os.path.join(workdir, "run-tracker")
-            self.assertTrue(
-                os.path.isdir(run_tracker_dir), f"dir path {run_tracker_dir} does not exist!"
-            )
-            run_tracker_sub_dirs = (
-                os.path.join(run_tracker_dir, dir_name)
-                for dir_name in os.listdir(run_tracker_dir)
-                if dir_name != "latest"
-            )
-            for run_tracker_sub_dir in run_tracker_sub_dirs:
-                info_path = os.path.join(run_tracker_sub_dir, "info")
-                assert os.path.isfile(info_path) is True
-                with open(info_path, "r") as info_f:
-                    lines = dict(line.split(": ", 1) for line in info_f.readlines())
-                    if "goals" in lines["cmd_line"]:
-                        self.assertIn("parent_build_id", lines)
-                    else:
-                        self.assertNotIn("parent_build_id", lines)

tests/python/pants_test/pantsd/BUILD

@@ -52,7 +52,6 @@ python_tests(
     'examples/src/python/example:hello_directory',
     'testprojects/src/python:bad_requirements_directory',
     'testprojects/src/python:coordinated_runs_directory',
-    'testprojects/src/python:nested_runs_directory',
     'testprojects/src/python:print_env_directory',
   ],
   tags = ['integration'],

tests/python/pants_test/pantsd/test_pantsd_integration.py

@@ -676,22 +676,3 @@ def test_unhandled_exceptions_only_log_exceptions_once(self):
                 "pants.bin.daemon_pants_runner._PantsRunFinishedWithFailureException: Terminated with 1",
                 result.stderr_data,
             )
-
-    def test_inner_runs_dont_deadlock(self):
-        """Create a pantsd run that calls testprojects/src/python/nested_runs with the appropriate
-        bootstrap options to avoid restarting pantsd.
-
-        Regression test for issue https://github.com/pantsbuild/pants/issues/7881
-        When a run under pantsd calls pants with pantsd inside it, the inner run will time out
-        waiting for the outer run to end.
-
-        NB: testprojects/src/python/nested_runs assumes that the pants.toml file is in ${workdir}/pants.toml
-        """
-        config = {"GLOBAL": {"pantsd_timeout_when_multiple_invocations": 1}}
-        with self.pantsd_successful_run_context(extra_config=config) as ctx:
-            result = ctx.runner(
-                ["run", "testprojects/src/python/nested_runs", "--", ctx.workdir], expected_runs=2
-            )
-            ctx.checker.assert_started()
-            self.assert_success(result)
-            self.assertNotIn("Another pants invocation is running", result.stderr_data)