Add notification or documentation for: Adding original entries to new group configuration unexpectedly modifies original entries

[LIM0000]

JabRef version

Latest development branch build (please note build date below)

Operating system

Windows

Details on version and operating system

Windows 10

Checked with the latest development build

• I made a backup of my libraries before testing the latest development version.
• I have tested the latest development version and the problem persists

Steps to reproduce the behaviour

Steps to reproduce:
Part 1:

1. Create a new library.
2. Click on Add group button.
3. Input name test1 for the group and create the group.
4. Create 2 articles in All entries.
5. Input author field with steven and mike for each article respectively.

Part 2:

1. Right click on test1 group -> Edit group
2. Select Searching for a keyword under Collect by.
3. Input author as field and steven as keyword, then click on ok button and ok button for warning dialog.
   (test1 group has a steven article entry)

Part 3:

1. Right click on test1 group -> Edit group
2. Select Searching for a keyword under Collect by.
3. Input author as field and mike as keyword, then click on ok button and ok button for warning dialog.
   (test1 group now has 2 articles which are steven,mike and mike articles)

EXPECTED:
I am expecting that part 3 will return both `steven` and `mike` articles.

ACTUAL:
However, 1 of the articles' author field has been merged to steven,mike. Is this an expected behaviour?
From my understanding, Collect by should only return filtered entries without any entries modification.

Appendix

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Log File

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[ThiloteE]

Could you please show what is in the {} biblatex source tab of all shown entries?

I have come across a similar odd behaviour (see #8527 (comment)), but back then, I was not able to reproduce with a fresh library.

[LIM0000]

steven article (somehow merge into "steven, mike" after edited the group with searching keyword)

mike article

[LIM0000]

I have done more researches to issue and understand what is happening behind the hood of the issue with Searching for a keyword.

When user edits a group from Explicit selection to Searching for a keyword, the group type changes from ExplicitGroup to WordKeywordGroup. This WordKeywordGroup functions DYNAMICALLY. Using example from above, we set the field as author and keyword as mike in WordKeywordGroup, this group will automatically assign ANY NEW entries that have author=mike into it.

However, if user assigns any entry that does not have author=mike and the group is WordKeywordGroup, the group will have to modify the field and the value of the entry. Using example from above again, we set the field as author and keyword as mike in WordKeywordGroup, if user "forcefully" assigns entry with author=steven into this group, it does not make sense for WordKeywordGroup as this entry does not have mike in it. Therefore, WordKeywordGroup will append mike into the entry's author field which results in author=steven, mike. Now the WordKeywordGroup able to add the entry into its group.

WordKeywordGroup behaves correctly. Although there is a warning dialog asking users whether they would like to assign the original group's entries to this group, there is no warning dialog about modifying users' entries.

[ThiloteE]

Great!

I would suggest to append to the Change of Grouping Method: Assign the original group's entries to this group? dialogue the following notification:

(Note: If original entries lack keywords to qualify for the new group configuration, confirming here will add them)

Alternatively, this info could be added to JabRef's documentation (here)