test: Show all headers in emacs reply tests

By default, emacs hides the User-Agent and References headers when
composing mail. This is a good thing for users, but a bad thing for
testing, since we can create ugly or invalid headers and not have it
show up in the tests.

By setting message-hidden-headers to an empty list, we force emacs to
show all the headers, so we can check that they're correct. Users
won't see this, but it will let us catch future bugs.

As a side-effect, this breaks all the reply tests, since there is a
bug with the References and User-Agent headers, fixed in the next commit.

test/emacs

@@ -267,17 +267,23 @@ EOF
 test_expect_equal_file OUTPUT EXPECTED
 
 test_begin_subtest "Reply within emacs"
-test_emacs '(notmuch-search "subject:\"testing message sent via SMTP\"")
+test_subtest_known_broken
+test_emacs '(let ((message-hidden-headers ''()))
+	    (notmuch-search "subject:\"testing message sent via SMTP\"")
 	    (notmuch-test-wait)
 	    (notmuch-search-reply-to-thread)
-	    (test-output)'
+	    (test-output))'
 sed -i -e 's/^In-Reply-To: <.*>$/In-Reply-To: <XXX>/' OUTPUT
+sed -i -e 's/^References: <.*>$/References: <XXX>/' OUTPUT
+sed -i -e 's,^User-Agent: Notmuch/.* Emacs/.*,User-Agent: Notmuch/XXX Emacs/XXX,' OUTPUT
 cat <<EOF >EXPECTED
 From: Notmuch Test Suite <test_suite@notmuchmail.org>
 To: user@example.com
 Subject: Re: Testing message sent via SMTP
 In-Reply-To: <XXX>
 Fcc: ${MAIL_DIR}/sent
+References: <XXX>
+User-Agent: Notmuch/XXX Emacs/XXX
 --text follows this line--
 Notmuch Test Suite <test_suite@notmuchmail.org> writes:
 
@@ -286,19 +292,24 @@ EOF
 test_expect_equal_file OUTPUT EXPECTED
 
 test_begin_subtest "Reply from alternate address within emacs"
+test_subtest_known_broken
 add_message '[from]="Sender <sender@example.com>"' \
 	     [to]=test_suite_other@notmuchmail.org
 
-test_emacs "(notmuch-search \"id:\\\"${gen_msg_id}\\\"\")
+test_emacs "(let ((message-hidden-headers '()))
+	    (notmuch-search \"id:\\\"${gen_msg_id}\\\"\")
 	    (notmuch-test-wait)
 	    (notmuch-search-reply-to-thread)
-	    (test-output)"
+	    (test-output))"
+sed -i -e 's,^User-Agent: Notmuch/.* Emacs/.*,User-Agent: Notmuch/XXX Emacs/XXX,' OUTPUT
 cat <<EOF >EXPECTED
 From: Notmuch Test Suite <test_suite_other@notmuchmail.org>
 To: Sender <sender@example.com>
 Subject: Re: ${test_subtest_name}
 In-Reply-To: <${gen_msg_id}>
 Fcc: ${MAIL_DIR}/sent
+References: <${gen_msg_id}>
+User-Agent: Notmuch/XXX Emacs/XXX
 --text follows this line--
 Sender <sender@example.com> writes:
 
@@ -307,20 +318,25 @@ EOF
 test_expect_equal_file OUTPUT EXPECTED
 
 test_begin_subtest "Reply from address in named group list within emacs"
+test_subtest_known_broken
 add_message '[from]="Sender <sender@example.com>"' \
             '[to]=group:test_suite@notmuchmail.org,someone@example.com\;' \
              [cc]=test_suite_other@notmuchmail.org
 
-test_emacs "(notmuch-search \"id:\\\"${gen_msg_id}\\\"\")
+test_emacs "(let ((message-hidden-headers '()))
+	    (notmuch-search \"id:\\\"${gen_msg_id}\\\"\")
 	    (notmuch-test-wait)
 	    (notmuch-search-reply-to-thread)
-	    (test-output)"
+	    (test-output))"
+sed -i -e 's,^User-Agent: Notmuch/.* Emacs/.*,User-Agent: Notmuch/XXX Emacs/XXX,' OUTPUT
 cat <<EOF >EXPECTED
 From: Notmuch Test Suite <test_suite@notmuchmail.org>
 To: Sender <sender@example.com>, someone@example.com
 Subject: Re: ${test_subtest_name}
 In-Reply-To: <${gen_msg_id}>
 Fcc: ${MAIL_DIR}/sent
+References: <${gen_msg_id}>
+User-Agent: Notmuch/XXX Emacs/XXX
 --text follows this line--
 Sender <sender@example.com> writes:
 
@@ -329,15 +345,20 @@ EOF
 test_expect_equal_file OUTPUT EXPECTED
 
 test_begin_subtest "Reply within emacs to a multipart/mixed message"
-test_emacs '(notmuch-show "id:20091118002059.067214ed@hikari")
+test_subtest_known_broken
+test_emacs '(let ((message-hidden-headers ''()))
+	    (notmuch-show "id:20091118002059.067214ed@hikari")
 		(notmuch-show-reply)
-		(test-output)'
+		(test-output))'
+sed -i -e 's,^User-Agent: Notmuch/.* Emacs/.*,User-Agent: Notmuch/XXX Emacs/XXX,' OUTPUT
 cat <<EOF >EXPECTED
 From: Notmuch Test Suite <test_suite@notmuchmail.org>
 To: Adrian Perez de Castro <aperez@igalia.com>, notmuch@notmuchmail.org
 Subject: Re: [notmuch] Introducing myself
 In-Reply-To: <20091118002059.067214ed@hikari>
 Fcc: ${MAIL_DIR}/sent
+References: <20091118002059.067214ed@hikari>
+User-Agent: Notmuch/XXX Emacs/XXX
 --text follows this line--
 Adrian Perez de Castro <aperez@igalia.com> writes:
 
@@ -388,15 +409,20 @@ EOF
 test_expect_equal_file OUTPUT EXPECTED
 
 test_begin_subtest "Reply within emacs to a multipart/alternative message"
-test_emacs '(notmuch-show "id:cf0c4d610911171136h1713aa59w9cf9aa31f052ad0a@mail.gmail.com")
+test_subtest_known_broken
+test_emacs '(let ((message-hidden-headers ''()))
+	    (notmuch-show "id:cf0c4d610911171136h1713aa59w9cf9aa31f052ad0a@mail.gmail.com")
 		(notmuch-show-reply)
-		(test-output)'
+		(test-output))'
+sed -i -e 's,^User-Agent: Notmuch/.* Emacs/.*,User-Agent: Notmuch/XXX Emacs/XXX,' OUTPUT
 cat <<EOF >EXPECTED
 From: Notmuch Test Suite <test_suite@notmuchmail.org>
 To: Alex Botero-Lowry <alex.boterolowry@gmail.com>, notmuch@notmuchmail.org
 Subject: Re: [notmuch] preliminary FreeBSD support
 In-Reply-To: <cf0c4d610911171136h1713aa59w9cf9aa31f052ad0a@mail.gmail.com>
 Fcc: ${MAIL_DIR}/sent
+References: <cf0c4d610911171136h1713aa59w9cf9aa31f052ad0a@mail.gmail.com>
+User-Agent: Notmuch/XXX Emacs/XXX
 --text follows this line--
 Alex Botero-Lowry <alex.boterolowry@gmail.com> writes:
 
@@ -424,19 +450,24 @@ EOF
 test_expect_equal_file OUTPUT EXPECTED
 
 test_begin_subtest "Quote MML tags in reply"
+test_subtest_known_broken
 message_id='test-emacs-mml-quoting@message.id'
 add_message [id]="$message_id" \
 	    "[subject]='$test_subtest_name'" \
 	    '[body]="<#part disposition=inline>"'
-test_emacs "(notmuch-show \"id:$message_id\")
+test_emacs "(let ((message-hidden-headers '()))
+	      (notmuch-show \"id:$message_id\")
 	      (notmuch-show-reply)
-	      (test-output)"
+	      (test-output))"
+sed -i -e 's,^User-Agent: Notmuch/.* Emacs/.*,User-Agent: Notmuch/XXX Emacs/XXX,' OUTPUT
 cat <<EOF >EXPECTED
 From: Notmuch Test Suite <test_suite@notmuchmail.org>
 To: 
 Subject: Re: Quote MML tags in reply
 In-Reply-To: <test-emacs-mml-quoting@message.id>
 Fcc: ${MAIL_DIR}/sent
+References: <test-emacs-mml-quoting@message.id>
+User-Agent: Notmuch/XXX Emacs/XXX
 --text follows this line--
 Notmuch Test Suite <test_suite@notmuchmail.org> writes: