JabRef 4.0.0-dev--snapshot--2017-03-01--braces-checking-followup--488825af5

This ticket is supposed to mention a few problems with the implementation of the groups panel in the current development version 4 of JabRef.

I realized that saving a huge database (>10,000 entries) takes now much longer than with version 3.8.2 (database was saved nearly instantaneously), especially when the entry preview is open. Indeed, the usage of the CPU suddenly spikes to nearly 100% and it takes several seconds for JabRef to save the database. In the meantime it behaves as if JabRef had crashed. This might be related to some issues of the groups feature which I report below. Performance issues with version 4 have also been reported elsewhere: #2587 and #2588

Generally the implementation of the groups feature in JabRef 4 is:

• slower than the old one (especially when you try to save changes in your database while the entry preview is open - see above). Furthermore, the first time you try to expand "All entries" it takes a couple of seconds before the expanded groups are shown.
• does not allow to hide the number of entries (which might cause some performance issues on large databases): hit number is calculated async, thus there shouldn't be a performance problem
• cannot be opened with all subgroups expanded as default: fixed (expansion status will be kept across sessions)
• displays group titles with underscore, e.g. "Alpha_taxonomy" as "Alpha_(t)axonomy", i. e. brackets are added to the first character following the underscore: consequence of a known bug Latex2Unicode Formatter: Captial letters after an underscore are wrapped in braces #2664
• does not offer the same options that were available with the old group panel, when rightclicking onto one of the groups. E.g., the menu points
  • "Edit group": Add a few groups actions #2674
  • "Add group",
  • "Remove groups and subgroups"
  • "Remove group keep subgroups": Add a few groups actions #2674
  • "Remove subgroups": Add a few groups actions #2674
  • "Expand subtree": removed in Remove the following commands in the right-click menu of a group: #2697
  • "Collapse subtree": removed in Remove the following commands in the right-click menu of a group: #2697
  • "Move: Up, Down, Left, Right": removed in Remove the following commands in the right-click menu of a group: #2697
  • "Sort alphabetically"
  • "Assign entry selection to this group": Add a few groups actions #2674
  • "Assign entry selection exclusively to this group": removed
  • "Exclude entry selection from this group": Add a few groups actions #2674

don't appear to be available. Only "Add subgroups" appears to be available at the moment.

• The group settings
  • "Intersection": issue Allow selection of multiple groups #2786
  • "Union": issue Allow selection of multiple groups #2786
  • "Inverted": issue Allow selection of multiple groups #2786
  • "Edit group membership": edit mode was removed
  • "Gray out non-hits": moved to preferences Fix a few smaller group related things  #2705
  • "Hide non-hits": moved to preferences Fix a few smaller group related things  #2705
  • "Highlight overlapping groups": removed in Remove the following commands in the right-click menu of a group: #2697
  • "Show number of elements contained in each group" (see b)): not necessary
  • "Automatically assign new entry to selected groups": option moved to preferences

don't appear to be available at the moment.

• You cannot drag'n'drop an entry onto a group to assign it to that group (has already been reported here: Adding an entry to a group by dragging no longer possible #2590): Implemented in Add drag and drop for groups -> groups #2632
• You cannot drag'n'drop a group onto another group to assign it as the subgroup of the other group: implemented in Add drag and drop for groups -> groups #2632