Format integration tests code

Split lines that were too long, adjusted intendation and fixed typos.

Signed-off-by: Catalin Dumitru <catdum@amazon.com>

integration_tests/test_benchmark.py

@@ -1,29 +1,43 @@
 # Copyright 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved.
 # SPDX-License-Identifier: Apache-2.0
-"""Compare benchmark results before and after a pull request."""
+"""
+Compare benchmark results before and after a pull request.
 
-import os, subprocess
-import pytest
+This test works properly on the local machine only when the environment
+variables REMOTE and BASE_BRANCH are set. Otherwise the default values
+are "origin" for the remote name of the upstream repository and "master"
+for the name of the base branch, and this test may not work as expected.
+"""
+
+import os
+import subprocess
 
 from utils import get_repo_root_path
 
-# Repository being tested (as configured with Buildkite).
-UPSTREAM_REPO_URL = os.environ['BUILDKITE_REPO']
-# Base branch as configured with Buildkite.
-BASE_BRANCH = os.environ['BUILDKITE_PULL_REQUEST_BASE_BRANCH']
-# File used for saving the results of cargo bench when running on the PR branch.
+REMOTE = \
+    os.environ.get('BUILDKITE_REPO') or \
+    os.environ.get('REMOTE') or \
+    "origin"
+BASE_BRANCH = \
+    os.environ.get('BUILDKITE_PULL_REQUEST_BASE_BRANCH') or \
+    os.environ.get('BASE_BRANCH') or \
+    "master"
+# File used for saving the results of cargo bench
+# when running on the PR branch.
 PR_BENCH_RESULTS_FILE = "pr_bench_results"
-# File used for saving the results of cargo bench when running on the upstream branch.
+# File used for saving the results of cargo bench
+# when running on the upstream branch.
 UPSTREAM_BENCH_RESULTS_FILE = "upstream_bench_results"
 
+
 def test_bench():
     """Runs benchmarks before and after and compares the results."""
     os.chdir(get_repo_root_path())
 
     # Get numbers for current HEAD.
     return_code, stdout, stderr = _run_cargo_bench(PR_BENCH_RESULTS_FILE)
-    # Even if it is the first time this test is run, the benchmark tests should pass.
-    # For this purpose, we need to explicitly check the return code.
+    # Even if it is the first time this test is run, the benchmark tests should
+    # pass. For this purpose, we need to explicitly check the return code.
     assert return_code == 0, "stdout: {}\n stderr: {}".format(stdout, stderr)
 
     # Get numbers from upstream tip, without the changes from the current PR.
@@ -31,37 +45,47 @@ def test_bench():
     return_code, stdout, stderr = _run_cargo_bench(UPSTREAM_BENCH_RESULTS_FILE)
 
     # Before checking any results, let's just go back to the PR branch.
-    # This way we make sure that the cleanup always happens even if the test fails.
+    # This way we make sure that the cleanup always happens even if the test
+    # fails.
     _git_checkout_pr_branch()
 
     if return_code == 0:
-        # In case this benchmark also ran successfully, we can call critcmp and compare the results.
+        # In case this benchmark also ran successfully, we can call critcmp and
+        # compare the results.
         _run_critcmp()
     else:
-        # The benchmark did not run successfully, but it might be that it is because a benchmark does not exist.
-        # In this case, we do not want to fail the test.
+        # The benchmark did not run successfully, but it might be that it is
+        # because a benchmark does not exist. In this case, we do not want to
+        # fail the test.
         if "error: no bench target named `main`" in stderr:
-            # This is a bit of a &*%^ way of checking if the benchmark does not exist.
-            # Hopefully it will be possible to check it in another way...soon
-            print("There are no benchmarks in master. No comparison can happen.")
+            # This is a bit of a &*%^ way of checking if the benchmark does not
+            # exist. Hopefully it will be possible to check it in another way
+            # ...soon
+            print(
+                "There are no benchmarks in master. No comparison can happen."
+            )
         else:
-            assert return_code == 0, "stdout: {}\n stderr: {}".format(stdout, stderr)
+            assert return_code == 0, "stdout: {}\n stderr: {}".format(
+                stdout, stderr)
 
 
 def _run_cargo_bench(baseline):
     """Runs `cargo bench` and tags the baseline."""
     process = subprocess.run(
-        "cargo bench --bench main --all-features -- --noplot --save-baseline {}"
-        .format(baseline),
+        "cargo bench --bench main --all-features -- --noplot "
+        "--save-baseline {}".format(baseline),
         shell=True, stderr=subprocess.PIPE, stdout=subprocess.PIPE
     )
 
-    return process.returncode, process.stdout.decode('utf-8'), process.stderr.decode('utf-8')
+    return process.returncode, process.stdout.decode('utf-8'),\
+        process.stderr.decode('utf-8')
 
 
 def _run_critcmp():
     p = subprocess.run(
-        "critcmp {} {}".format(UPSTREAM_BENCH_RESULTS_FILE, PR_BENCH_RESULTS_FILE),
+        "critcmp {} {}".format(
+            UPSTREAM_BENCH_RESULTS_FILE, PR_BENCH_RESULTS_FILE
+        ),
         shell=True, check=True,
         stdout=subprocess.PIPE,
         stderr=subprocess.PIPE
@@ -71,9 +95,10 @@ def _run_critcmp():
     print('ERRORS')
     print(p.stderr.decode('utf-8'))
 
+
 def _git_checkout_upstream_branch():
     subprocess.run(
-        "git fetch {} {}".format(UPSTREAM_REPO_URL, BASE_BRANCH),
+        "git fetch {} {}".format(REMOTE, BASE_BRANCH),
         shell=True, check=True
     )
     subprocess.run(
@@ -81,6 +106,7 @@ def _git_checkout_upstream_branch():
         shell=True, check=True
     )
 
+
 def _git_checkout_pr_branch():
     subprocess.run(
         "git checkout -",