Comparing legacy and modernized code

Three surfaces show you code, and they answer different questions.

Legacy Code Viewer

The legacy source as uploaded. You will usually arrive here from a scenario: a scenario's related files open at the lines they were annotated with, so you land on the code a behaviour was extracted from rather than at the top of a file.

Use it to check the as-is specification against reality — see Reviewing the as-is specification.

New Code Viewer

The modernized codebase as it stands, on the integration branch. Use it to see what has actually been built, as opposed to what the feature list says has been built.

Where a feature's work is still on its own branch — status completed, displayed as "Implemented on Feature Branch" — it is not here yet. That is the most common reason for "the feature says it is done but I cannot find the code".

Compare

A side-by-side comparison of legacy and modernized code. Compare runs as a job, so a comparison you have run before stays available rather than being recomputed each time you look.

It answers the question neither viewer does on its own: has the behaviour that was in there come out here? That is a question about two codebases at once, and reading them in separate tabs is how details get missed.

What none of them is

None of these is evidence that the new code does what the old code did. Reading code side by side tells you the shapes match; only running the scenarios tells you the behaviour matches. See Test runs and reports.