Add an option to skip environment creation for tests (#5760)

When iteration on tests, running the `dd_environment` every time can be
expensive. This adds a new `--skip-env` flag to `ddev test` to remove
that step, and run the tests directly.

datadog_checks_dev/datadog_checks/dev/_env.py

@@ -16,6 +16,7 @@
 
 E2E_FIXTURE_NAME = 'dd_environment'
 TESTING_PLUGIN = 'DDEV_TESTING_PLUGIN'
+SKIP_ENVIRONMENT = 'DDEV_SKIP_ENV'
 
 
 def e2e_active():

datadog_checks_dev/datadog_checks/dev/plugin/pytest.py

@@ -13,6 +13,7 @@
     AGENT_COLLECTOR_SEPARATOR,
     E2E_FIXTURE_NAME,
     E2E_PARENT_PYTHON,
+    SKIP_ENVIRONMENT,
     TESTING_PLUGIN,
     e2e_active,
     e2e_testing,
@@ -61,14 +62,17 @@ def datadog_agent():
 
 @pytest.fixture(scope='session', autouse=True)
 def dd_environment_runner(request):
+    # Skip the runner if the skip environment variable is specified
+    do_skip = os.getenv(SKIP_ENVIRONMENT) == 'true'
+
     testing_plugin = os.getenv(TESTING_PLUGIN) == 'true'
 
     # Do nothing if no e2e action is triggered and continue with tests
-    if not testing_plugin and not e2e_active():  # no cov
+    if not testing_plugin and not e2e_active() and not do_skip:  # no cov
         return
     # If e2e tests are being run it means the environment has
     # already been spun up so we prevent another invocation
-    elif e2e_testing():  # no cov
+    elif e2e_testing() or do_skip:  # no cov
         # Since the scope is `session` there should only ever be one definition
         fixture_def = request._fixturemanager._arg2fixturedefs[E2E_FIXTURE_NAME][0]
 

datadog_checks_dev/datadog_checks/dev/tooling/commands/test.py

@@ -6,7 +6,7 @@
 
 import click
 
-from ..._env import E2E_PARENT_PYTHON
+from ..._env import E2E_PARENT_PYTHON, SKIP_ENVIRONMENT
 from ...subprocess import run_command
 from ...utils import chdir, file_exists, get_ci_env_vars, remove_path, running_on_ci
 from ..constants import get_root
@@ -40,6 +40,7 @@ def display_envs(check_envs):
 @click.option('--passenv', help='Additional environment variables to pass down')
 @click.option('--changed', is_flag=True, help='Only test changed checks')
 @click.option('--cov-keep', is_flag=True, help='Keep coverage reports')
+@click.option('--skip-env', is_flag=True, help='Skip environment creation and assume it is already running')
 @click.option('--pytest-args', '-pa', help='Additional arguments to pytest')
 @click.pass_context
 def test(
@@ -61,6 +62,7 @@ def test(
     passenv,
     changed,
     cov_keep,
+    skip_env,
     pytest_args,
 ):
     """Run tests for Agent-based checks.
@@ -108,6 +110,10 @@ def test(
         'DDEV_COV_MISSING': coverage_show_missing_lines,
     }
 
+    if skip_env:
+        test_env_vars[SKIP_ENVIRONMENT] = 'true'
+        test_env_vars['TOX_TESTENV_PASSENV'] += f' {SKIP_ENVIRONMENT}'
+
     if passenv:
         test_env_vars['TOX_TESTENV_PASSENV'] += f' {passenv}'