send-email: teach git send-email option to translate aliases

git send-email has support for converting shorthand alias names to
canonical email addresses via the alias file. It supports a wide variety
of alias file formats based on popular email program file formats.

Other programs, such as b4, would like the ability to convert aliases in
the same way as git send-email without needing to re-implement the logic
for understanding the many file formats.

Teach git send-email a new option, --translate-aliases, which will
enable this functionality. Similar to --dump-aliases, this option works
like a new mode of operation for git send-email.

When run with --translate-aliases, git send-email reads from standard
input and converts any provided alias into its canonical name and email
according to the alias file. Each expanded name and address is printed
to standard output, one per line.

Signed-off-by: Jacob Keller <jacob.keller@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 104 insertions, 0 deletions

diff --git a/t/t9001-send-email.sh b/t/t9001-send-email.sh
index c96d6955b9..c5e862694e 100755
--- a/t/t9001-send-email.sh
+++ b/t/t9001-send-email.sh
@@ -2120,6 +2120,110 @@ test_expect_success '--dump-aliases must be used alone' '
 	test_must_fail git send-email --dump-aliases --to=janice@example.com -1 refs/heads/accounting
 '
 
+test_translate_aliases () {
+	msg="$1" && shift &&
+	filetype="$1" && shift &&
+	aliases="$1" && shift &&
+	printf '%s\n' "$@" >expect &&
+	cat >.tmp-email-aliases &&
+	printf '%s\n' "$aliases" >aliases &&
+
+	test_expect_success $PREREQ "$msg" '
+		clean_fake_sendmail && rm -fr outdir &&
+		git config --replace-all sendemail.aliasesfile \
+			"$(pwd)/.tmp-email-aliases" &&
+		git config sendemail.aliasfiletype "$filetype" &&
+		git send-email --translate-aliases <aliases 2>errors >actual &&
+		test_cmp expect actual
+	'
+}
+
+test_translate_aliases '--translate-aliases sendmail format' \
+	'sendmail' \
+	'alice bcgrp' \
+	'Alice W Land <awol@example.com>' \
+	'Robert Bobbyton <bob@example.com>' \
+	'chloe@example.com' \
+	'Other <o@example.com>' <<-\EOF
+	alice: Alice W Land <awol@example.com>
+	bob: Robert Bobbyton <bob@example.com>
+	chloe: chloe@example.com
+	abgroup: alice, bob
+	bcgrp: bob, chloe, Other <o@example.com>
+	EOF
+
+test_translate_aliases '--translate-aliases mutt format' \
+	'mutt' \
+	'donald bob' \
+	'Donald C Carlton <donc@example.com>' \
+	'Robert Bobbyton <bob@example.com>' <<-\EOF
+	alias alice Alice W Land <awol@example.com>
+	alias donald Donald C Carlton <donc@example.com>
+	alias bob Robert Bobbyton <bob@example.com>
+	alias chloe chloe@example.com
+	EOF
+
+test_translate_aliases '--translate-aliases mailrc format' \
+	'mailrc' \
+	'chloe eve alice' \
+	'chloe@example.com' \
+	'Eve <eve@example.com>' \
+	'Alice W Land <awol@example.com>' <<-\EOF
+	alias alice   "Alice W Land <awol@example.com>"
+	alias eve     "Eve <eve@example.com>"
+	alias bob     "Robert Bobbyton <bob@example.com>"
+	alias chloe   chloe@example.com
+	EOF
+
+test_translate_aliases '--translate-aliases pine format' \
+	'pine' \
+	'eve bob bcgrp' \
+	'eve@example.com' \
+	'bob@example.com' \
+	'bob@example.com' \
+	'chloe@example.com' \
+	'Other <o@example.com>' <<-\EOF
+	alice	Alice W Land	awol@example.com		Friend
+	eve	Eve	eve@example.com
+	bob	Robert Bobbyton	bob@example.com
+	chloe		chloe@example.com
+	bcgrp		(bob, chloe, Other <o@example.com>)
+	EOF
+
+test_translate_aliases '--translate-aliases gnus format' \
+	'gnus' \
+	'alice chloe eve' \
+	'awol@example.com' \
+	'chloe@example.com' \
+	'eve@example.com' <<-\EOF
+	(define-mail-alias "alice" "awol@example.com")
+	(define-mail-alias "eve" "eve@example.com")
+	(define-mail-alias "bob" "bob@example.com")
+	(define-mail-alias "chloe" "chloe@example.com")
+	EOF
+
+test_expect_success $PREREQ '--translate-aliases passes valid addresses through' '
+	cat >expect <<-\EOF &&
+	Other <o@example.com>
+	EOF
+	cat >aliases <<-\EOF &&
+	Other <o@example.com>
+	EOF
+	git send-email --translate-aliases <aliases >actual &&
+	test_cmp expect actual
+'
+
+test_expect_success $PREREQ '--translate-aliases passes unknown aliases through' '
+	cat >expect <<-\EOF &&
+	blargh
+	EOF
+	cat >aliases <<-\EOF &&
+	blargh
+	EOF
+	git send-email --translate-aliases <aliases >actual &&
+	test_cmp expect actual
+'
+
 test_expect_success $PREREQ 'aliases and sendemail.identity' '
 	test_must_fail git \
 		-c sendemail.identity=cloud \