Create scenario tests for init templates

pyproject.toml

@@ -132,6 +132,7 @@ xfail_strict = true
 markers = [
     "slow: marks tests as slow (deselect with '-m \"not slow\"')",
 ]
+addopts = "--ignore=tests/spread"
 
 [tool.coverage.run]
 branch = true

tests/spread/commands/init-extensions/task.yaml

@@ -11,6 +11,17 @@ environment:
   PROFILE/fastapi: fastapi-framework
   CHARMCRAFT_ENABLE_EXPERIMENTAL_EXTENSIONS: "true"
 
+prepare: |
+  tests.pkgs install pipx python3-venv
+  pipx install --force tox
+
+restore: |
+  pushd test-init
+  charmcraft clean
+  popd
+
+  rm -rf test-init
+
 execute: |
   # Required for fetch-libs to succeed since the libraries are not available on
   # the staging environment
@@ -20,14 +31,12 @@ execute: |
 
   mkdir -p test-init
   cd test-init
-  charmcraft init --profile "${PROFILE}"
+  charmcraft init --profile "${PROFILE}" --name hello-world
   charmcraft fetch-libs
   charmcraft pack --verbose
   test -f *.charm
 
-restore: |
-  pushd test-init
-  charmcraft clean
-  popd
-
-  rm -rf test-init
+  # expand charmcraft.yaml for the scenario tests to work
+  charmcraft expand-extensions > charmcraft-expanded.yaml
+  mv charmcraft-expanded.yaml charmcraft.yaml
+  ~/.local/bin/tox -c ../tox.ini -e unit

tests/spread/commands/init-extensions/tests/unit/test_charm.py

@@ -0,0 +1,28 @@
+# Copyright 2024 Canonical Ltd.
+# See LICENSE file for licensing details.
+
+"""Smoke scenario test for paas-charm based init templates."""
+
+import os
+import pathlib
+
+import charm
+import scenario
+import scenario.errors
+
+
+def test_smoke():
+    """The purpose of this test is that the charm does not raise on a handled event."""
+    os.chdir(pathlib.Path(charm.__file__).parent.parent)
+    ctx = scenario.Context(charm.HelloWorldCharm)
+    container_name = next(iter(ctx.charm_spec.meta["containers"].keys()))
+    container = scenario.Container(
+        name=container_name,
+        can_connect=True,
+    )
+    state_in = scenario.State(containers={container})
+    out = ctx.run(
+        ctx.on.pebble_ready(container),
+        state_in,
+    )
+    assert type(out.unit_status) in (scenario.WaitingStatus, scenario.BlockedStatus)

tests/spread/commands/init-extensions/tox.ini

@@ -0,0 +1,34 @@
+# Copyright 2024 Canonical
+# See LICENSE file for licensing details.
+
+[tox]
+no_package = True
+env_list = unit
+min_version = 4.0.0
+
+[vars]
+src_path = {tox_root}/test-init/src
+tests_path = {tox_root}/tests
+
+[testenv]
+set_env =
+    PYTHONPATH = {tox_root}/test-init/lib:{[vars]src_path}
+    PYTHONBREAKPOINT=pdb.set_trace
+    PY_COLORS=1
+pass_env =
+    PYTHONPATH
+
+[testenv:unit]
+description = Run unit tests
+deps =
+    pytest
+    ops-scenario
+    -r {tox_root}/test-init/requirements.txt
+commands =
+    pytest \
+        --tb native \
+        -v \
+        -s \
+	--confcutdir={tox_root} \
+        {posargs} \
+        {[vars]tests_path}/unit