shared_state does not share instance_config, inventory or ephemeral directory across scenarios

[J-PC]

Prerequisites

• This was not already reported in the past (duplicate check)
• It does reproduce it with code from main branch (latest unreleased version)
• I include a minimal example for reproducing the bug
• The bug is not trivial, as for those a direct pull-request is preferred
• Running pip check does not report any conflicts
• I was able to reproduce the issue on a different machine
• The issue is not specific to any driver other than 'default' one

Environment

molecule 25.12.0 using python 3.12 :
- ansible:2.16.0
- default:25.12.0 from molecule
- vagrant:25.8.12 from molecule_plugins
- openstack:25.8.12 from molecule_plugins requiring collections: openstack.cloud>=2.1.0
- podman:25.8.12 from molecule_plugins requiring collections: containers.podman>=1.7.0 ansible.posix>=1.3.0
- gce:25.8.12 from molecule_plugins requiring collections: google.cloud>=1.0.2 community.crypto>=1.8.0
- ec2:25.8.12 from molecule_plugins
- docker:25.8.12 from molecule_plugins requiring collections: community.docker>=3.10.2 ansible.posix>=1.4.0
- containers:25.8.12 from molecule_plugins requiring collections: ansible.posix>=1.3.0 community.docker>=1.9.1
- containers.podman>=1.8.1
- azure:25.8.12 from molecule_plugins

OS: Fedora 42 WSL

What happened

Summary

When enabling shared_state in Molecule, the documentation states that component scenarios can reuse resources created by the default scenario.
However, only the create/destroy lifecycle is actually shared — not the necessary runtime state, such as:

• instance_config.yml
• inventories
• ephemeral directory
• connection parameters for hosts created by the default scenario

This results in component scenarios being unable to access the instances created in the default scenario, causing provisioning failures.

---

Expected Behavior

Based on the documentation, enabling shared_state should allow:

• shared ephemeral state across scenarios
• default scenario managing create/destroy for all others
• component scenarios accessing resources created by default
• consistent instance information (instance_config, inventory)

At minimum, this should include:

• a shared instance_config.yml
• a shared inventory
• a shared ephemeral directory
• consistent MOLECULE_INSTANCE_CONFIG across scenarios

---

Actual Behavior

In practice:

• each scenario gets a different MOLECULE_EPHEMERAL_DIRECTORY
• each scenario has its own instance_config.yml
• the default scenario’s inventory and connection data are not propagated
• component scenarios cannot connect to hosts created by the default scenario

Example environment variables printed during runs:

MOLECULE_EPHEMERAL_DIRECTORY: ~/.ansible/tmp/molecule.XYZ.default
MOLECULE_EPHEMERAL_DIRECTORY: ~/.ansible/tmp/molecule.ABC.component

This contradicts the documented behavior and makes multi-scenario reuse impossible.

---

Steps to Reproduce

1. Create two scenarios: default and component.

2. Enable shared state:

   scenario:
     shared_state: true

3. Run:

   molecule converge -s default
molecule converge -s component --shared-state

4. Observe:

   • separate ephemeral directories
   • separate instance_config.yml
   • component scenario cannot reach hosts created in default

---

Impact

This prevents Molecule from being used in:

• chained scenarios
• multi-scenario test architectures
• large roles where infrastructure should only be created once
• any scenario that relies on the default scenario’s created instances

The feature behaves differently from what the documentation suggests.

---

Proposed Fix

Option A — Implement full shared-state

• share ephemeral directory
• share instance_config
• share inventory
• ensure consistent MOLECULE_INSTANCE_CONFIG across scenarios

Option B — Update documentation

Explain that shared_state currently only shares create/destroy, but does not share:

• instance_config
• ephemeral directory
• inventory

---

Additional Information

• This issue has been identified with the default driver
• The problem is reproducible with any scenario and any provisioning workflow.

Reproducing example

[bramwalet]

I've experienced the same thing retrofitting Molecule collection tests into an existing project. My inventory wasn't shared across scenario's.
TL;DR: check if a galaxy.yml is present in your project root and that it contains a collection configuration.

---

While retrofitting Molecule into my project, I've used this guide as a reference https://docs.ansible.com/projects/molecule/getting-started-collections/. But I had troubles sharing the inventory across scenario's and I had to execute molecule inside the extensions folder. While troubleshooting the problem, I've noticed this GitHub issue.

When I exactly followed the steps (including running ansible-creator) of the guide in a new Ansible project, shared_state works as expected. When I execute molecule test --all in this new Ansible project, I've noticed that the output starts with:
INFO Found config file <workspace path>/extensions/molecule/config.yml

In my 'retrofitted' project, this was not the case. Hence the extensions/molecule/config.yml was not applied.

After looking at the code, it appears that the file galaxy.yml influences this behaviour. When this file exists with a collection configuration, Molecule applies MOLECULE_COLLECTION_ROOT which has glob MOLECULE_COLLECTION_ROOT = "extensions/molecule".

When I added a galaxy.yml in the project root folder, executed molecule test -all in the project root directory, things started to work.

[p3trk]

Hello
I'm experiencing reported issue even with galaxy.yml defined.

Molecule use same state file for all sequences, but ephemeral directory is not shared.

$ molecule --version
INFO     Found config file /lab/ansible/molecule-testing-shared-state/foo/bar/extensions/molecule/config.yml
molecule 25.12.0 using python 3.10
    ansible:2.17.14
    default:25.12.0 from molecule
    

$ molecule --debug test -s component
...
INFO     default ➜ create: Executing
MOLECULE_EPHEMERAL_DIRECTORY: /lab/.ansible/tmp/molecule._N4r.default
MOLECULE_STATE_FILE: /lab/.ansible/tmp/molecule._N4r/state.yml
...
INFO     component ➜ converge: Executing
MOLECULE_EPHEMERAL_DIRECTORY: /lab/.ansible/tmp/molecule._N4r.component
MOLECULE_STATE_FILE: /lab/.ansible/tmp/molecule._N4r/state.yml