In long diffs, it can become impossible to spot small changes in larger blocks of moved code. This may be either a method that was moved from the top to the bottom of a file, or a long test file that was split in many.
Fortunately, Git offers a special highlighting mode that directs the reader's attention to relevant code parts:
git diff --color-moved=dimmed-zebra
It will dim lines that were moved around without changes, and highlight changed lines. See this SO answer for an illustration.
To easily use dimmed-zebra mode, configure an alias:
# ~/.gitconfig [alias] dz = diff --color-moved=dimmed-zebra