pandoc/test/command/5876.md

```
% pandoc -s -t native --data-dir=command/5876 --metadata-file=5876.yaml
Hello
^D
Pandoc
  Meta
    { unMeta =
        fromList
          [ ( "desc"
            , MetaInlines
                [ Str "Found"
                , Space
                , Str "in"
                , Space
                , Str "metadata"
                , Space
                , Str "directory."
                ]
            )
          ]
    }
  [ Para [ Str "Hello" ] ]
```
```
% pandoc -s -t native --data-dir=command/5876 --metadata-file=command/5876.yaml
Hello
^D
Pandoc
  Meta
    { unMeta =
        fromList
          [ ( "desc"
            , MetaInlines
                [ Str "Found"
                , Space
                , Str "in"
                , Space
                , Str "working"
                , Space
                , Str "directory."
                ]
            )
          ]
    }
  [ Para [ Str "Hello" ] ]
```
```
% pandoc -s -t native --data-dir=command/5876 --metadata-file=does-not-exist.yaml
Hello
^D
Could not find metadata file does-not-exist.yaml
```
```
% pandoc -s -t native --metadata-file=does-not-exist.yaml
Hello
^D
Could not find metadata file does-not-exist.yaml
```