diff-mode-menu is a variable defined in `diff-mode.el'.
Its value is shown below.

Menu for `diff-mode'.


(keymap "Diff" (Jump\ to\ Source menu-item "Jump to Source" diff-goto-source :help "Jump to the corresponding source line") (Apply\ hunk menu-item "Apply hunk" diff-apply-hunk :help "Apply the current hunk to the source file and go to the next") (Test\ applying\ hunk menu-item "Test applying hunk" diff-test-hunk :help "See whether it's possible to apply the current hunk") (Apply\ diff\ with\ Ediff menu-item "Apply diff with Ediff" diff-ediff-patch :help "Call `ediff-patch-file' on the current buffer") (Create\ Change\ Log\ entries menu-item "Create Change Log entries" diff-add-change-log-entries-other-window :help "Create ChangeLog entries for the changes in the diff buffer") (nil menu-item "-----") (Reverse\ direction menu-item "Reverse direction" diff-reverse-direction :help "Reverse the direction of the diffs") (Context\ ->\ Unified menu-item "Context -> Unified" diff-context->unified :help "Convert context diffs to unified diffs") (Unified\ ->\ Context menu-item "Unified -> Context" diff-unified->context :help "Convert unified diffs to context diffs") (Remove\ trailing\ whitespace menu-item "Remove trailing whitespace" diff-delete-trailing-whitespace :help "Remove trailing whitespace problems introduced by the diff") (Show\ trailing\ whitespace menu-item "Show trailing whitespace" whitespace-mode :button (:toggle bound-and-true-p whitespace-mode) :help "Show trailing whitespace in modified lines") (nil-11 menu-item "-----") (Split\ hunk menu-item "Split hunk" diff-split-hunk :enable (diff-splittable-p) :help "Split the current (unified diff) hunk at point into two hunks") (Ignore\ whitespace\ changes menu-item "Ignore whitespace changes" diff-ignore-whitespace-hunk :help "Re-diff the current hunk, ignoring whitespace differences") (Highlight\ fine\ changes menu-item "Highlight fine changes" diff-refine-hunk :help "Highlight changes of hunk at point at a finer granularity") (Kill\ current\ hunk menu-item "Kill current hunk" diff-hunk-kill :help "Kill current hunk") (Kill\ current\ file\'s\ hunks menu-item "Kill current file's hunks" diff-file-kill :help "Kill all current file's hunks") (nil-17 menu-item "-----") (Previous\ Hunk menu-item "Previous Hunk" diff-hunk-prev :help "Go to the previous count'th hunk") (Next\ Hunk menu-item "Next Hunk" diff-hunk-next :help "Go to the next count'th hunk") (Previous\ File menu-item "Previous File" diff-file-prev :help "Go to the previous count'th file") (Next\ File menu-item "Next File" diff-file-next :help "Go to the next count'th file"))