pandoc/test/command/duplicate_attributes.md

```
% pandoc
[span]{.foobar style="color:blue" class="zip" style="color:red"}
^D
2> [WARNING] Ignoring duplicate attribute style="color:red".
<p><span class="foobar zip" style="color:blue">span</span></p>
```
HTML writer: Add warnings on duplicate attribute values. This prevents emitting invalid HTML. Ultimately it would be good to prevent this in the types themselves, but this is better for now. T.P.Logging: Add DuplicateAttribute constructor to LogMessage. [API change] 2021-03-10 19:19:40 +01:00			```
			`% pandoc`
			`[span]{.foobar style="color:blue" class="zip" style="color:red"}`
			`^D`
Update command tests to distinguish stderr and test exit status. 2022-01-22 00:01:50 +01:00			`2> [WARNING] Ignoring duplicate attribute style="color:red".`
HTML writer: Add warnings on duplicate attribute values. This prevents emitting invalid HTML. Ultimately it would be good to prevent this in the types themselves, but this is better for now. T.P.Logging: Add DuplicateAttribute constructor to LogMessage. [API change] 2021-03-10 19:19:40 +01:00			`<p><span class="foobar zip" style="color:blue">span</span></p>`
			```