This design task is to resolve how to handle undo steps in the text editor (and possible text fields in the future).

Possible options:

• Keep current behavior - each key is a single unto step.
• Group by character type / action.
• Group using a timer, so characters typed in quick succession are put into a single undo step.
  
  The timer can be a preference, so users who type slowly or prefer to have the current behavior can either increase the timer or set it to zero.

Note:

• Using a timer may be unpredictable especially when the users typing speed hovers around the limit - undo groupings may seem unpredictable.
• Using whole words may have the disadvantage that large blocks get undone (not fine grained enough).
• Having grouped undo makes it difficult to test undo/redo (developer detail, even so - noting it here).

Proposal

• Undo grouping will only be done for single character insertion/removal.
• Undo wont group edits separated by cursor motion.
• Word level grouping has the same delimiters as pressing Ctrl-Left/Right, this means whitespace/punctuation & alpha-numeric characters will be undone/redone in blocks.

• Have a preference for the text editor to group undo by words or characters. (this allows undo testing code to behave predictably).

Maybe there are other options, @William Reynish (billreynish) we discussed this a while ago.

Creating because D6283: Add undo grouped to Insert and Delete text operator was submitted which.