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##### SUMMARY
https://github.com/ansible/ansible/blob/devel/lib/ansible/modules/cloud/misc/terraform.py#L353 expects the plan_file to be a filename not a path to a file.inside of project_path. Works with relative paths but not with absolute paths. Lucky for me I use a path inside project_path but it worked before with paths outside too.

##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME
<!--- Write the short name of the module, plugin, task or feature below, use your best guess if unsure -->
terraform
##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
```paste below
ansible 2.8.1
  config file = /home/adam/.ansible.cfg
  configured module search path = ['/home/adam/.ansible/plugins/modules', '/usr/share/ansible/plugins/modules']
  ansible python module location = /home/adam/.local/lib/python3.6/site-packages/ansible
  executable location = /home/adam/.local/bin/ansible
  python version = 3.6.8 (default, Jan 14 2019, 11:02:34) [GCC 8.0.1 20180414 (experimental) [trunk revision 259383]]
```

##### CONFIGURATION
<!--- Paste verbatim output from "ansible-config dump --only-changed" between quotes -->
```paste below

```

##### OS / ENVIRONMENT
<!--- Provide all relevant information below, e.g. target OS versions, network device firmware, etc. -->


##### STEPS TO REPRODUCE
<!--- Describe exactly how to reproduce the problem, using a minimal test-case -->

<!--- Paste example playbooks or commands between quotes below -->
```yaml
use absolute path for plan_file 
```

<!--- HINT: You can paste gist.github.com links for larger files -->

##### EXPECTED RESULTS
<!--- Describe what you expected to happen when running the steps above -->
uses the filepath provided

##### ACTUAL RESULTS
<!--- Describe what actually happened. If possible run with extra verbosity (-vvvv) -->

<!--- Paste verbatim command output between quotes -->
```paste below
TASK [run terraform apply] ***************************************************************************************************************************************************************************************************************************************************************
fatal: [localhost]: FAILED! => {"changed": false, "msg": "Could not find plan_file \"/home/.../plan.tfplan\", check the path and try again."}
```

global module
    module = AnsibleModule(
        argument_spec=dict(
            project_path=dict(required=True, type='path'),
            binary_path=dict(type='path'),
            workspace=dict(required=False, type='str', default='default'),
            purge_workspace=dict(type='bool', default=False),
            state=dict(default='present', choices=['present', 'absent', 'planned']),
            variables=dict(type='dict'),
            variables_file=dict(type='path'),
            plan_file=dict(type='path'),
            state_file=dict(type='path'),
            targets=dict(type='list', default=[]),
            lock=dict(type='bool', default=True),
            lock_timeout=dict(type='int',),
            force_init=dict(type='bool', default=False),
            backend_config=dict(type='dict', default=None),
        ),
        required_if=[('state', 'planned', ['plan_file'])],
        supports_check_mode=True,
    )