-diffcore-pathspec: For Ignoring Files Outside Our Consideration
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-
-The first transformation in the chain is diffcore-pathspec, and
-is controlled by giving the pathname parameters to the
-'git-diff-{asterisk}' commands on the command line. The pathspec is used
-to limit the world diff operates in. It removes the filepairs
-outside the specified set of pathnames. E.g. If the input set
-of filepairs included:
-
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-:100644 100644 bcd1234... 0123456... M junkfile
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-
-but the command invocation was `git diff-files myfile`, then the
-junkfile entry would be removed from the list because only "myfile"
-is under consideration.
-
-Implementation note. For performance reasons, 'git-diff-tree'
-uses the pathname parameters on the command line to cull set of
-filepairs it feeds the diffcore mechanism itself, and does not
-use diffcore-pathspec, but the end result is the same.
-
-