cg-diff(1): make diff between two git trees

NAME

-c: Colorize the diff output
-p: Show diff to the parent of the current commit (or the commit specified by the -r parameter).
-s: Summarize the diff by showing a histogram for removed and added lines (similar to the output of diffstat(1)) and information about added and renamed files and mode changes.
-r FROM_ID[..TO_ID]: Specify the revisions to diff using either -r rev1..rev2 or -r rev1 -r rev2. If no revision is specified, the current working tree is implied. Note that no revision is different from empty revision which means -r rev.. compares between rev and HEAD, while -r rev compares between rev and working tree.
-m: Base the diff at the merge base of the -r arguments (defaulting to HEAD and origin).
-h, --help: Print usage summary.
--long-help: Print user manual. The same as found in cg-diff(1).

PAGER: The pager to display log information in, defaults to less.
PAGER_FLAGS: Flags to pass to the pager.
CG_LESS: This is what the $LESS environment variable value will be set to before invoking $PAGER. It defaults to $LESS concatenated with the R flag to allow displaying of colorized output.