Just some more details:

It would be great to see test documents that focus on one feature and show different aspects of one feature. E.g. documents showing different parts of complex categories would be highly appreciated.

Some features are but not limited to them:
-trendlines
-complex categories
-number formats in charts
-different cahrttypes
-error bars
-...

The files will be collected here and for easy access moved to the other Libreoffice test files at:

http://cgit.freedesktop.org/libreoffice/contrib/test-files/tree/

Created attachment 58991 [details]
GráficosBarrasApiladasHorizontales_ChartBarStackedHorizontal

A graph with horizontal stacked bars, with transparent background to use formatted cells as background with the twelve months, to visualize the fruit production distributed along the year. I was make to answer a request in the Spanish OOo forum.

Created attachment 59186 [details]
Performance Smooth 3D lines Sample Chart Document

The disadvantage of that first example is that it's not easy to find out for what tests it should be used. 

I believe test documents should fulfill following criteria

Document Name should give a hint concerning test
Spreadsheet document should contain information in a sheet named "TestInstructions":

Author of document:
Tests for:
Expected test result:
How to reproduce (facultative):
Unexpected (facultative):

I attach "Performance3DSmoothLines.ods" following these ideas

Here is a query leading to Bugs with charts:
<https://bugs.freedesktop.org/buglist.cgi?list_id=59306&field0-0-0=attachments.filename&query_format=advanced&type0-0-0=casesubstring&value0-0-0=.ods&component=Chart&product=LibreOffice>

For collecting test charts I propose following proceeding:

1. Run this modified shared query: 
<https://bugs.freedesktop.org/buglist.cgi?cmdtype=dorem&remaction=run&namedcmd=ChartSampleRework&sharer_id=19321&list_id=59322>
2. Attach reworked sample document here with some hints
3. "Edit Search" from step 1
4. Add Bug ID number of bug where you found the document to 
   Second line "Bug ID" of "Custom Search"
5. Search
6. Remember Search

I hope that proceeding will work, I do not have much experience with those shared queries.

@Markus: May be you want to give some additional hints concerning requirements for optimum test documents?

My concern was qualified, the common editing of a named shared query will not work. So please add Reviewed bugs here in the whiteboard behind "AlreadyReviewedBugs:", I will keep the query up to date.

> @Markus: May be you want to give some additional hints concerning requirements
> for optimum test documents?

Hey,

so ideally we want a set of newly written test documents that each contain a set of charts focus on one feature. Ideally these documents should be licensed MPL/LGPLv3+ because we are using the test documents in our in-build tests and they will become part of the source code but will not end up in the release.

I'm happy with maybe 2 to 5 real world documents that stress several different ffeatures at once but not more because they make it quite hard to find and debug regressions.

So I think we should not try to use existing bug documents because they often are not focused on one single feature.

I still hope that we get some users contributing test docs.

Created attachment 59647 [details]
Horizontals Bars with different trendlines

Is this simple enough?? Just drawing a chart and use different trendlines on it.
Or should i just use more data??

(In reply to comment #7)
> Created attachment 59647 [details]
> Horizontals Bars with different trendlines
> 
> Is this simple enough?? Just drawing a chart and use different trendlines on
> it.
> Or should i just use more data??

It is a good test document.

Since you are a dev you can even think about extending the chart2 layout dumper in chart2/source/view/charttypes/ChartView.cxx. Right now the dumper only covers some basic information but we should extend the dumped information and finally I need to spend some time enabling the regression test.

@Florian:
When you create test documents, please use a structure similar to "Performance Smooth 3D lines Sample Chart Document", but with test instructions contents in the same sheet as the textcase itself. So all contribution of an author for a particular test is all together in 1 sheet, and if an other author has an idea for a related test, he can simply add a sheet, upload the new and obsolete the old version of the document.

I believe sample charts for axis label (number) format would be useful (beneath lots of other test cases).

Created attachment 60231 [details]
#39827 slightly edited test document for bug #39827

#39827: Is this kay too..?

Another document, which I created for a bug: https://bugs.freedesktop.org/show_bug.cgi?id=48858

@Florian: can you just quickly write a mail to the qa or dev list confirming that your contributions including test files is under LGPLv3+/MPL?

@Rainer, Florian: We can't just use bug files because they are not covered by LGPLv3+/MPL. Either we need to ask the author of the files if they would provide the document under the correct licenses or we create our own test documents. Personally I prefer number two for the in-build test but collecting here a set of nice test document for manual testing might be also a good idea.

adding LibreOffice developer list as CC to unresolved EasyHacks for better visibility.

see e.g. http://nabble.documentfoundation.org/minutes-of-ESC-call-td4076214.html for details

The attachment as shown in Bug 71075 should be the simplest chart test template. (Chart copy between applications).

Unassigning, this bug doesnt block: multiple people can work on in in parallel without interference.

Not my scope

Re-evaluating the EasyHack in 2022.

I am closing this issue as now we have several examples here:
https://git.libreoffice.org/test-files/+/refs/heads/master/calc/chart/

And also here:
sc/qa/uitest/data
sc/qa/unit/data