add: introduce "--renormalize"

Make it safer to normalize the line endings in a repository.
Files that had been commited with CRLF will be commited with LF.

The old way to normalize a repo was like this:

 # Make sure that there are not untracked files
 $ echo "* text=auto" >.gitattributes
 $ git read-tree --empty
 $ git add .
 $ git commit -m "Introduce end-of-line normalization"

The user must make sure that there are no untracked files,
otherwise they would have been added and tracked from now on.

The new "add --renormalize" does not add untracked files:

 $ echo "* text=auto" >.gitattributes
 $ git add --renormalize .
 $ git commit -m "Introduce end-of-line normalization"

Note that "git add --renormalize <pathspec>" is the short form for
"git add -u --renormalize <pathspec>".

While at it, document that the same renormalization may be needed,
whenever a clean filter is added or changed.

Helped-By: Junio C Hamano <gitster@pobox.com>
Signed-off-by: Torsten Bögershausen <tboegi@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 30 insertions, 0 deletions

diff --git a/t/t0025-crlf-renormalize.sh b/t/t0025-crlf-renormalize.sh
new file mode 100755
index 0000000000..9d9e02a211
--- /dev/null
+++ b/t/t0025-crlf-renormalize.sh
@@ -0,0 +1,30 @@
+#!/bin/sh
+
+test_description='CRLF renormalization'
+
+. ./test-lib.sh
+
+test_expect_success setup '
+	git config core.autocrlf false &&
+	printf "LINEONE\nLINETWO\nLINETHREE\n" >LF.txt &&
+	printf "LINEONE\r\nLINETWO\r\nLINETHREE\r\n" >CRLF.txt &&
+	printf "LINEONE\r\nLINETWO\nLINETHREE\n" >CRLF_mix_LF.txt &&
+	git add . &&
+	git commit -m initial
+'
+
+test_expect_success 'renormalize CRLF in repo' '
+	echo "*.txt text=auto" >.gitattributes &&
+	git add --renormalize "*.txt" &&
+	cat >expect <<-\EOF &&
+	i/lf w/crlf attr/text=auto CRLF.txt
+	i/lf w/lf attr/text=auto LF.txt
+	i/lf w/mixed attr/text=auto CRLF_mix_LF.txt
+	EOF
+	git ls-files --eol |
+	sed -e "s/	/ /g" -e "s/  */ /g" |
+	sort >actual &&
+	test_cmp expect actual
+'
+
+test_done