Enable import-error check on //testing Enables the import-error pylint check on //testing. Most errors are fixed by updating the PYTHONPATH used by pylint to include the necessary directories, although some import errors are simply suppressed (most commonly for vpython-provided modules). Also takes this opportunity to add comments about where each block of non-standard imports comes from. This was already present in a number of places, but not everywhere. Bug: 353942917 Change-Id: I506d35e5a6ae56471618e6b4af57dd2ecb64dd7b Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6092016 Commit-Queue: Brian Sheedy <bsheedy@chromium.org> Reviewed-by: Ben Pastene <bpastene@chromium.org> Reviewed-by: Paul Semel <paulsemel@chromium.org> Cr-Commit-Position: refs/heads/main@{#1396194} NOKEYCHECK=True GitOrigin-RevId: fe2702e96ce66e27b4e474f4a39eb78813de5fcc

diff --git a/exe_util_unittests.py b/exe_util_unittests.py
index 6ceeef5..8b3c439 100755
--- a/exe_util_unittests.py
+++ b/exe_util_unittests.py

@@ -6,7 +6,8 @@
 
 import sys
 
-from pyfakefs import fake_filesystem_unittest
+# vpython-provided modules.
+from pyfakefs import fake_filesystem_unittest  # pylint: disable=import-error
 
 import exe_util
 

diff --git a/generate_script_unittests.py b/generate_script_unittests.py
index 059e75a..a2cd302 100755
--- a/generate_script_unittests.py
+++ b/generate_script_unittests.py

@@ -8,7 +8,8 @@
 import tempfile
 import unittest
 
-from pyfakefs import fake_filesystem_unittest
+# vpython-provided modules.
+from pyfakefs import fake_filesystem_unittest  # pylint: disable=import-error
 
 from generate_script import _parse_args
 from generate_script import _generate_script

diff --git a/main_program_unittests.py b/main_program_unittests.py
index 89e8f8f..c72e8bd 100755
--- a/main_program_unittests.py
+++ b/main_program_unittests.py

@@ -10,7 +10,8 @@
 import tempfile
 import unittest
 
-from pyfakefs import fake_filesystem_unittest
+# vpython-provided modules.
+from pyfakefs import fake_filesystem_unittest  # pylint: disable=import-error
 
 from test_results import TestResult
 

diff --git a/rust_main_program_unittests.py b/rust_main_program_unittests.py
index 5d10507..e4bd838 100755
--- a/rust_main_program_unittests.py
+++ b/rust_main_program_unittests.py

@@ -8,7 +8,8 @@
 import tempfile
 import unittest
 
-from pyfakefs import fake_filesystem_unittest
+# vpython-provided modules.
+from pyfakefs import fake_filesystem_unittest  # pylint: disable=import-error
 
 from test_results import TestResult
 

diff --git a/test_filtering_unittests.py b/test_filtering_unittests.py
index bc70cb3..6d66051 100755
--- a/test_filtering_unittests.py
+++ b/test_filtering_unittests.py

@@ -9,7 +9,8 @@
 import tempfile
 import unittest
 
-from pyfakefs import fake_filesystem_unittest
+# vpython-provided modules.
+from pyfakefs import fake_filesystem_unittest  # pylint: disable=import-error
 
 import test_filtering
 from test_filtering import _TestFilter