Subject: 27.0.50; On git log-view-diff does not work for moved files.

From: David Koppelman <[email-masked]>
Date: Wed, 08 Jan 2020 14:48:45 -0600

With (setq vc-git-print-log-follow t) visit a file in a git repo that
was moved from some other directory and which had changes when in that
other directory. Start log view, C-x v =, move the cursor to a commit
made in the file's former location, and press d (log-view-diff). Rather
than showing a diff, a message reporting no changes is shown.

This flaw was noted in bug 8756, covering vc-diff/log-view, but was
left to a follow on bug.
(https://debbugs.gnu.org/cgi/bugreport.cgi?bug=8756).

Interestingly, vc-annotate has no trouble with renames. See
commit d1e4c4037e88f3256db19813805d03f8ad0291fa.

In GNU Emacs 27.0.50 (build 5, x86_64-pc-linux-gnu, GTK+ Version 3.22.30)
 of 2019-12-20 built on cyc.ece.lsu.edu
Repository revision: 85a60da92d4db5c87ecfa152501d246425550fc3
Repository branch: master
Windowing system distributor 'The X.Org Foundation', version 11.0.12004000
System Description: Scientific Linux 7.7 (Nitrogen)

Configured using:
 'configure CFLAGS=-O3 --without-pop'

Configured features:
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ACL LIBSELINUX GNUTLS LIBXML2 FREETYPE HARFBUZZ M17N_FLT LIBOTF XFT ZLIB
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GMP

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Major mode: log

Minor modes in effect:
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