How do I follow a change across files?

Trace It is the written walkthrough of a pull request, for when you want to read at your own pace. It takes a large pull request one feature at a time instead of one file at a time: pick a feature and DiffGuardian walks it across every file it touches, in the order the code actually runs, explaining each hop. Want it spoken instead? See Talk to your pull request, a separate feature.

Trace It is available on Pro. On Basic the Trace It tab stays where it is and opens an upgrade prompt.

#The problem it solves

A pull request that spans dozens of files is rarely one change — it is usually several, interleaved. Reviewing it in file order means never seeing any single feature end to end.

#How it works

DiffGuardian breaks the pull request into the features it actually ships. Choose one, and Trace It moves across every file that feature touches, in the order the code actually runs, with the diff shown at each step in context.

#Using it

1. Open a pull request and let the review finish.
2. Choose a feature from the feature list.
3. Step through the trace. Each stop shows the file, the changed lines, what that step contributes to the feature, why it changed, what happens next, and any finding raised there.
4. A step worth commenting on can be adopted as a comment, becoming an ordinary draft you can edit before submitting.
5. Move to the next feature when you are satisfied you understand this one.

#See the flow

Alongside the trace, DiffGuardian shows the flow as a graph from the actual call graph, not a hand-authored picture that drifts out of date. Use it to see the blast radius of a change before you approve it — see Blast radius for how that graph is built.

DiffGuardian is a desktop app for macOS, Windows and Linux, and works with pull requests on GitHub, GitLab and Bitbucket.

#Limits

• Trace It is a Pro feature. On Basic the tab is visible but opens an upgrade prompt instead.