Which function or code is for calculating the highlighting parts for two strings?

[roadfar]

As lines 5, 6, 13, and 23 show in the following figure show, which function or code is for calculating the highlighting parts (i.e., the string start index and end index) of the left and right lines?

[th1000s]

That is done at infer_edits(..) in src/edits.rs:24. Plus there is --color-moved support, if git provides this information.