Support for modifying source in compare clipboard editor

[SougandhS]

For #1862 (comment)

follow-up to #1862

Supports modifying the source from compare editor itself

My.Movie.mp4

[github-actions]

Test Results

 1 977 files  ±0   1 977 suites  ±0   1h 37m 12s ⏱️ + 8m 29s
 4 743 tests ±0   4 719 ✅ ±0   24 💤 ±0  0 ❌ ±0 
14 229 runs  ±0  14 047 ✅ ±0  182 💤 ±0  0 ❌ ±0 

Results for commit 9663a82. ± Comparison against base commit c905608.

♻️ This comment has been updated with latest results.

[SougandhS]

One more thing I have to handle

[SougandhS]

My.Movie2.mp4

[SougandhS]

Hi @iloveeclipse, I have added the missing modify functionality 👍

[vogella]

@iloveeclipse I think you suggest that @SougandhS adds this. Can you review?

[vogella]

@SougandhS can you solve the merge conflict?

[SougandhS]

@SougandhS can you solve the merge conflict?

Done 👍

[vogella]

A few review notes (haven't pulled the branch, just read the diff):

1. Likely bug in setContent (around line 218): the branch if (selectionLength <= 1) overwrites the entire file with newContent. With a 1‑character partial selection, this silently replaces the whole file with just the edited char. The condition should be if (!partialSelection), mirroring how getContents decides.

2. Mutable per-action state on a singleton delegate: currentResouce, offSet, len, partialSelection are now instance fields mutated inside the per-file loop and later read by EditableFileNode#setContent after the compare editor is open. A later invocation can flip behavior of an already-open compare editor. Pass these as parameters / capture them in the node instead.

3. Sentinel mixed with Integer.MAX_VALUE: offSet/len use -1 as "no selection", and the else branch then constructs new EditableFileNode(currentResouce, 0, Integer.MAX_VALUE). It only works because getContents clamps via Math.min. A single boolean inside the node would be cleaner.

4. Dialogs from model code: EditableFileNode#getContents and setContent call MessageDialog.openError(...) directly; these can be invoked off the UI thread by the compare framework. Prefer ILog.of(getClass()).error(...) and rethrow / return, so the framework surfaces the error.

5. Cosmetics: typo currentResouce (should be currentResource), field offSet (should be offset), variable name page2, and ClipboardCompare.java is missing a trailing newline. Pre-existing typo "Comparision Failed" could be fixed in passing.

6. No tests added; given the offset/length math, a test that opens a clipboard compare on a partial selection and writes back would be valuable.

7. Edge case: captured selectionOffset/selectionLength become stale if the underlying file is modified between opening the compare and saving.

[SougandhS]

A few review notes (haven't pulled the branch, just read the diff):

Thanks, will check this comments 👍