docs: update python contributing guide (#9)

* docs: update python contributing guide

Adds details about blacken, updates version for system tests,
and shows how to pass through pytest arguments.

Source-Author: Chris Cotter <cjcotter@google.com>
Source-Date: Mon Feb 8 17:13:36 2021 -0500
Source-Repo: googleapis/synthtool
Source-Sha: 4679e7e415221f03ff2a71e3ffad75b9ec41d87e
Source-Link: googleapis/synthtool@4679e7e

* build(python): enable flakybot on library unit and system tests

Source-Author: Bu Sun Kim <8822365+busunkim96@users.noreply.github.com>
Source-Date: Wed Feb 17 14:10:46 2021 -0700
Source-Repo: googleapis/synthtool
Source-Sha: d17674372e27fb8f23013935e794aa37502071aa
Source-Link: googleapis/synthtool@d176743

.gitignore

@@ -50,8 +50,10 @@ docs.metadata
 
 # Virtual environment
 env/
+
+# Test logs
 coverage.xml
-sponge_log.xml
+*sponge_log.xml
 
 # System test environment variables.
 system_tests/local_test_setup

.kokoro/build.sh

@@ -40,6 +40,16 @@ python3 -m pip uninstall --yes --quiet nox-automation
 python3 -m pip install --upgrade --quiet nox
 python3 -m nox --version
 
+# If this is a continuous build, send the test log to the FlakyBot.
+# See https://github.com/googleapis/repo-automation-bots/tree/master/packages/flakybot.
+if [[ $KOKORO_BUILD_ARTIFACTS_SUBDIR = *"continuous"* ]]; then
+  cleanup() {
+    chmod +x $KOKORO_GFILE_DIR/linux_amd64/flakybot
+    $KOKORO_GFILE_DIR/linux_amd64/flakybot
+  }
+  trap cleanup EXIT HUP
+fi
+
 # If NOX_SESSION is set, it only runs the specified session,
 # otherwise run all the sessions.
 if [[ -n "${NOX_SESSION:-}" ]]; then

CONTRIBUTING.rst

@@ -70,9 +70,14 @@ We use `nox <https://nox.readthedocs.io/en/latest/>`__ to instrument our tests.
 - To test your changes, run unit tests with ``nox``::
 
     $ nox -s unit-2.7
-    $ nox -s unit-3.7
+    $ nox -s unit-3.8
     $ ...
 
+- Args to pytest can be passed through the nox command separated by a `--`. For
+  example, to run a single test::
+
+    $ nox -s unit-3.8 -- -k <name of test>
+
   .. note::
 
     The unit tests and system tests are described in the
@@ -93,8 +98,12 @@ On Debian/Ubuntu::
 ************
 Coding Style
 ************
+- We use the automatic code formatter ``black``. You can run it using
+  the nox session ``blacken``. This will eliminate many lint errors. Run via::
+
+   $ nox -s blacken
 
-- PEP8 compliance, with exceptions defined in the linter configuration.
+- PEP8 compliance is required, with exceptions defined in the linter configuration.
   If you have ``nox`` installed, you can test that you have not introduced
   any non-compliant code via::
 
@@ -133,13 +142,18 @@ Running System Tests
 
 - To run system tests, you can execute::
 
-   $ nox -s system-3.7
+   # Run all system tests
+   $ nox -s system-3.8
    $ nox -s system-2.7
 
+   # Run a single system test
+   $ nox -s system-3.8 -- -k <name of test>
+
+
   .. note::
 
       System tests are only configured to run under Python 2.7 and
-      Python 3.7. For expediency, we do not run them in older versions
+      Python 3.8. For expediency, we do not run them in older versions
       of Python 3.
 
   This alone will not run the tests. You'll need to change some local

noxfile.py

@@ -93,6 +93,7 @@ def default(session):
     session.run(
         "py.test",
         "--quiet",
+        f"--junitxml=unit_{session.python}_sponge_log.xml",
         "--cov=google/cloud",
         "--cov=tests/unit",
         "--cov-append",
@@ -141,9 +142,21 @@ def system(session):
 
     # Run py.test against the system tests.
     if system_test_exists:
-        session.run("py.test", "--quiet", system_test_path, *session.posargs)
+        session.run(
+            "py.test",
+            "--quiet",
+            f"--junitxml=system_{session.python}_sponge_log.xml",
+            system_test_path,
+            *session.posargs,
+        )
     if system_test_folder_exists:
-        session.run("py.test", "--quiet", system_test_folder_path, *session.posargs)
+        session.run(
+            "py.test",
+            "--quiet",
+            f"--junitxml=system_{session.python}_sponge_log.xml",
+            system_test_folder_path,
+            *session.posargs,
+        )
 
 
 @nox.session(python=DEFAULT_PYTHON_VERSION)

synth.metadata

@@ -4,7 +4,7 @@
       "git": {
         "name": ".",
         "remote": "https://github.com/googleapis/python-binary-authorization.git",
-        "sha": "79588df8099840dd4d5ba562e8d7e704a564e2bf"
+        "sha": "ace8341e008546e0eb38638bf55699a92f6c81d4"
       }
     },
     {
@@ -19,14 +19,14 @@
       "git": {
         "name": "synthtool",
         "remote": "https://github.com/googleapis/synthtool.git",
-        "sha": "33366574ffb9e11737b3547eb6f020ecae0536e8"
+        "sha": "d17674372e27fb8f23013935e794aa37502071aa"
       }
     },
     {
       "git": {
         "name": "synthtool",
         "remote": "https://github.com/googleapis/synthtool.git",
-        "sha": "33366574ffb9e11737b3547eb6f020ecae0536e8"
+        "sha": "d17674372e27fb8f23013935e794aa37502071aa"
       }
     }
   ],