Allow environments to have existing deps

Honor existing deps in configured environments by adding the
auto-configured dependencies to existing ones rather than by replacing
them

Fixes #74

README.md

@@ -52,9 +52,11 @@ of the two options. Of course, tox can still be used to execute only one environ
 name directly via e.g. `tox -e roles-myrole-scenario`.
 
 If an environment already exists that matches the generated environment name, then this plugin
-will not settings specified directly in the tox.ini for that environment. Thus, if you need to customize
+will not override settings specified directly in the tox.ini for that environment. Thus, if you need to customize
 a particular run, then you can do so, but still take advantage of the filtering options and
-auto-generation of the environments for other scenarios and options.
+auto-generation of the environments for other scenarios and options. Dependencies defined in the standard
+way in tox.ini for any name collision environments will be augmented with the ones needed for
+running Molecule and lint.
 
 Configuration
 =============

src/tox_ansible/tox_helper.py

@@ -112,7 +112,10 @@ def customize_envconfig(self, config, options):
         config.commands = tox_case.get_commands(options)
         # Default deps to install molecule, etc
         do = DepOption()
-        config.deps = do.postprocess(config, tox_case.get_dependencies())
+        processed_deps = do.postprocess(config, tox_case.get_dependencies())
+        if config.deps:
+            processed_deps = config.deps + processed_deps
+        config.deps = processed_deps
         # Cannot run in {toxinidir}, which is default
         if not config.envdir or config.envdir == self.config.toxinidir:
             config.envdir = self.config.toxworkdir.join("ansible")

tests/fixtures/has_deps/galaxy.yml

@@ -0,0 +1,3 @@
+namespace: example
+name: foo
+version: 0.0.1

tests/fixtures/has_deps/roles/simple/molecule/default/converge.yml

@@ -0,0 +1,4 @@
+- name: test
+  hosts: all
+  roles:
+    - simple

tests/fixtures/has_deps/roles/simple/molecule/default/molecule.yml

@@ -0,0 +1,5 @@
+driver:
+  name: podman
+platforms:
+  - name: simple
+    image: fedora:latest

tests/fixtures/has_deps/roles/simple/tasks/main.yml

@@ -0,0 +1,2 @@
+- name: say hello
+  debug: msg='tox-ansible is the best'

tests/fixtures/has_deps/tox.ini

@@ -0,0 +1,13 @@
+[tox]
+skipdist = true
+envlist = lint_all
+
+[testenv]
+usedevelop = false
+skip_install = true
+deps =
+  otherdep
+
+[testenv:lint_all]
+deps =
+  notadep==1

tests/test_everything.py

@@ -109,6 +109,16 @@ def test_run_tox(directory, capfd):
     assert out == EXPECTED[directory]
 
 
+def test_tox_ini_deps_preserved(capfd):
+    with cd("tests/fixtures/has_deps"):
+        lint_out = run_tox(["--showconfig", "-e", "lint_all"], capfd)
+        simple_out = run_tox(["--showconfig", "-e", "roles-simple-default"], capfd)
+    deps = [m for m in lint_out.split("\n") if m.startswith("deps = ")][0]
+    assert "notadep==1" in deps
+    deps = [m for m in simple_out.split("\n") if m.startswith("deps = ")][0]
+    assert "otherdep" in deps
+
+
 @pytest.mark.parametrize(
     "target,value",
     [("scenario", "default"), ("driver", "openstack")],