Add semantic highlighting to the Java compare/merge viewer #2929

[Philipp0205]

This change installs semantic highlighting in CompilationUnitEditorAdapter.doSetInput() when the user preference is enabled to have the same syntax higlighting in the compare viewer than in the regular java editor.

Fixes #2929

Compare view before:

Compare view after:

[iloveeclipse]

Build is failing because of Eclips.org infrastructure issues.

[Copilot]

Pull request overview

Adds semantic highlighting support to the Java compare/merge viewer so it can render Java code with the same richer coloring as the regular Java editor (when enabled via preferences), addressing #2929.

Changes:

• Import semantic-highlighting support (SemanticHighlightings) into the compare viewer’s editor adapter.
• Install semantic highlighting in CompilationUnitEditorAdapter.doSetInput() when semantic highlighting is enabled and a Java element is available.

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[Philipp0205]

Build is failing because of Eclips.org infrastructure issues.

Good. I was already wondering 😄

[Philipp0205]

@iloveeclipse updated the PR. I would propose to integrate this which works for the Egit Revison side and create another PR for the Local History side.

[iloveeclipse]

08:53:24  [ERROR] /home/jenkins/agent/workspace/eclipse.jdt.ui-github_PR-2930/org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/compare/JavaMergeViewer.java:[88] 
08:53:24  [ERROR] 	import org.eclipse.jdt.internal.ui.javaeditor.SemanticHighlightings;
08:53:24  [ERROR] 	       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
08:53:24  [ERROR] The import org.eclipse.jdt.internal.ui.javaeditor.SemanticHighlightings is never used

[Philipp0205]

08:53:24  [ERROR] /home/jenkins/agent/workspace/eclipse.jdt.ui-github_PR-2930/org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/compare/JavaMergeViewer.java:[88] 
08:53:24  [ERROR] 	import org.eclipse.jdt.internal.ui.javaeditor.SemanticHighlightings;
08:53:24  [ERROR] 	       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
08:53:24  [ERROR] The import org.eclipse.jdt.internal.ui.javaeditor.SemanticHighlightings is never used

mea culpa, I should not just accept github suggestions 😄

[iloveeclipse]

You seem now use different email in the commits, so ECA is failing.

Please

1. Squash all commits to one
2. Use right email
3. Fetch from master
4. Rebase the commit on latest master
5. Force push on same branch

[iloveeclipse]

@Philipp0205 : you should set commit author to the mail you've set in your Eclipse.org account. ECA check works by matching mail set there to the commit author mail.

[iloveeclipse]

[Philipp0205]

You answer faster than I can correct my mistakes 😉