Repository: home-assistant/core
Pull request: Fix error if a `custom_sentences` file is empty
<!--
  You are amazing! Thanks for contributing to our project!
  Please, DO NOT DELETE ANY TEXT from this template! (unless instructed).
-->
## Breaking change
<!--
  If your PR contains a breaking change for existing users, it is important
  to tell them what breaks, how to make it work again and why we did this.
  This piece of text is published with the release notes, so it helps if you
  write it towards our users, not us.
  Note: Remove this section if this PR is NOT a breaking change.
-->
No

## Proposed change
<!--
  Describe the big picture of your changes here to communicate to the
  maintainers why we should accept this pull request. If it fixes a bug
  or resolves a feature request, be sure to link to that issue in the
  additional information section.
-->
Don't throw error when reading through empty `custom_sentences` files

## Type of change
<!--
  What type of change does your PR introduce to Home Assistant?
  NOTE: Please, check only 1! box!
  If your PR requires multiple boxes to be checked, you'll most likely need to
  split it into multiple PRs. This makes things easier and faster to code review.
-->

- [ ] Dependency upgrade
- [x] Bugfix (non-breaking change which fixes an issue)
- [ ] New integration (thank you!)
- [ ] New feature (which adds functionality to an existing integration)
- [ ] Deprecation (breaking change to happen in the future)
- [ ] Breaking change (fix/feature causing existing functionality to break)
- [ ] Code quality improvements to existing code or addition of tests

## Additional information
<!--
  Details are important, and help maintainers processing your PR.
  Please be sure to fill out additional details, if applicable.
-->

- This PR fixes or closes issue: fixes #93528
- This PR is related to issue: 
- Link to documentation pull request: 

## Checklist
<!--
  Put an `x` in the boxes that apply. You can also fill these out after
  creating the PR. If you're unsure about any of them, don't hesitate to ask.
  We're here to help! This is simply a reminder of what we are going to look
  for before merging your code.
-->

- [x] The code change is tested and works locally.
- [x] Local tests pass. **Your PR cannot be merged unless tests pass**
- [x] There is no commented out code in this PR.
- [x] I have followed the [development checklist][dev-checklist]
- [x] I have followed the [perfect PR recommendations][perfect-pr]
- [x] The code has been formatted using Black (`black --fast homeassistant tests`)
- [ ] Tests have been added to verify that the new code works.

If user exposed functionality or configuration variables are added/changed:

- [ ] Documentation added/updated for [www.home-assistant.io][docs-repository]

If the code communicates with devices, web services, or third-party tools:

- [ ] The [manifest file][manifest-docs] has all fields filled out correctly.  
      Updated and included derived files by running: `python3 -m script.hassfest`.
- [ ] New or updated dependencies have been added to `requirements_all.txt`.  
      Updated by running `python3 -m script.gen_requirements_all`.
- [ ] For the updated dependencies - a link to the changelog, or at minimum a diff between library versions is added to the PR description.
- [ ] Untested files have been added to `.coveragerc`.

<!--
  This project is very active and we have a high turnover of pull requests.

  Unfortunately, the number of incoming pull requests is higher than what our
  reviewers can review and merge so there is a long backlog of pull requests
  waiting for review. You can help here!
  
  By reviewing another pull request, you will help raise the code quality of
  that pull request and the final review will be faster. This way the general
  pace of pull request reviews will go up and your wait time will go down.
  
  When picking a pull request to review, try to choose one that hasn't yet
  been reviewed.

  Thanks for helping out!
-->

To help with the load of incoming pull requests:

- [ ] I have reviewed two other [open pull requests][prs] in this repository.

[prs]: https://github.com/home-assistant/core/pulls?q=is%3Aopen+is%3Apr+-author%3A%40me+-draft%3Atrue+-label%3Awaiting-for-upstream+sort%3Acreated-desc+review%3Anone+-status%3Afailure

<!--
  Thank you for contributing <3

  Below, some useful links you could explore:
-->
[dev-checklist]: https://developers.home-assistant.io/docs/development_checklist/
[manifest-docs]: https://developers.home-assistant.io/docs/creating_integration_manifest/
[quality-scale]: https://developers.home-assistant.io/docs/integration_quality_scale_index/
[docs-repository]: https://github.com/home-assistant/home-assistant.io
[perfect-pr]: https://developers.home-assistant.io/docs/review-process/#creating-the-perfect-pr


Problem statement:
HA assist erroring when you have empty custom sentence files
### The problem

If you make custom yaml files in the custom_sentences/{language} folder and have them blank, when you try to run assist you'll end up getting an error when you say/type something, even with default assist intents (turn on {xyz} light). The error HA shows is 

`"Unexpected error during intent recognition"`

In the logs, you end up with an error of 

`'NoneType' object has no attribute 'items'`

There is no other error on this other than the above in the logs, and it doesn't say where the issue is coming from (the empty files)

### What version of Home Assistant Core has the issue?

core-2023.5.4

### What was the last working version of Home Assistant Core?

_No response_

### What type of installation are you running?

Home Assistant OS

### Integration causing the issue

_No response_

### Link to integration documentation on our website

_No response_

### Diagnostics information

_No response_

### Example YAML snippet

_No response_

### Anything in the logs that might be useful for us?

```txt
Logger: homeassistant.components.assist_pipeline.pipeline
Source: components/conversation/default_agent.py:422
Integration: Assist pipeline (documentation, issues)
First occurred: 14:43:19 (1 occurrences)
Last logged: 14:43:19

Unexpected error during intent recognition
Traceback (most recent call last):
  File "/usr/src/homeassistant/homeassistant/components/assist_pipeline/pipeline.py", line 518, in recognize_intent
    conversation_result = await conversation.async_converse(
  File "/usr/src/homeassistant/homeassistant/components/conversation/__init__.py", line 373, in async_converse
    result = await agent.async_process(
  File "/usr/src/homeassistant/homeassistant/components/conversation/default_agent.py", line 163, in async_process
    lang_intents = await self.async_get_or_load_intents(language)
  File "/usr/src/homeassistant/homeassistant/components/conversation/default_agent.py", line 359, in async_get_or_load_intents
    return await self.hass.async_add_executor_job(
  File "/usr/local/lib/python3.10/concurrent/futures/thread.py", line 58, in run
    result = self.fn(*self.args, **self.kwargs)
  File "/usr/src/homeassistant/homeassistant/components/conversation/default_agent.py", line 422, in _get_or_load_intents
    merge_dict(
  File "/usr/local/lib/python3.10/site-packages/hassil/util.py", line 14, in merge_dict
    for key, value in new_dict.items():
AttributeError: 'NoneType' object has no attribute 'items'
```


### Additional information

_No response_

Hints from issue discussion:
Hey there @home-assistant/core, @synesthesiam, mind taking a look at this issue as it has been labeled with an integration (`conversation`) you are listed as a [code owner](https://github.com/home-assistant/core/blob/dev/CODEOWNERS#L224) for? Thanks!

<details>
<summary>Code owner commands</summary>


Code owners of `conversation` can trigger bot actions by commenting:

- `@home-assistant close` Closes the issue.
- `@home-assistant rename Awesome new title` Renames the issue.
- `@home-assistant reopen` Reopen the issue.
- `@home-assistant unassign conversation` Removes the current integration label and assignees on the issue, add the integration domain after the command.

</details>


<sub><sup>(message by CodeOwnersMention)</sup></sub>

---

[conversation documentation](https://www.home-assistant.io/integrations/conversation)
[conversation source](https://github.com/home-assistant/core/tree/dev/homeassistant/components/conversation)
<sub><sup>(message by IssueLinks)</sup></sub>

Commit message: Log warning file is invalid

Patch to review:
diff --git a/homeassistant/components/conversation/default_agent.py b/homeassistant/components/conversation/default_agent.py
index dccf394ab3fa1a..b53774f39cc2ff 100644
--- a/homeassistant/components/conversation/default_agent.py
+++ b/homeassistant/components/conversation/default_agent.py
@@ -419,9 +419,20 @@ def _get_or_load_intents(
                             encoding="utf-8"
                         ) as custom_sentences_file:
                             # Merge custom sentences
-                            merge_dict(
-                                intents_dict, yaml.safe_load(custom_sentences_file)
-                            )
+                            if isinstance(
+                                custom_sentences_yaml := yaml.safe_load(
+                                    custom_sentences_file
+                                ),
+                                dict,
+                            ):
+                                merge_dict(intents_dict, custom_sentences_yaml)
+                            else:
+                                _LOGGER.warning(
+                                    "Could not load custom sentences file language=%s (%s), path=%s",
+                                    language,
+                                    language_variation,
+                                    custom_sentences_file.name,
+                                )
 
                         # Will need to recreate graph
                         intents_changed = True


Code review comments:
diff_hunk: @@ -419,9 +419,20 @@ def _get_or_load_intents(
                             encoding="utf-8"
                         ) as custom_sentences_file:
                             # Merge custom sentences
-                            merge_dict(
-                                intents_dict, yaml.safe_load(custom_sentences_file)
-                            )
+                            if isinstance(
+                                custom_sentences_yaml := yaml.safe_load(
+                                    custom_sentences_file
+                                ),
+                                dict,
+                            ):
+                                merge_dict(intents_dict, custom_sentences_yaml)
+                            else:
+                                _LOGGER.warning(
+                                    "Could not load custom sentences file language=%s (%s), path=%s",
path: homeassistant/components/conversation/default_agent.py
text: @user1:
We should tell the user what went wrong.