format-patch: show base info before email signature

Any text below the "-- " for the email signature gets treated as part of
the signature, and many mail clients will trim it from the quoted text
for a reply.  Move it above the signature, so people can reply to it
more easily.

Similarly, when producing the patch as a MIME attachment, the
original code placed the base info after the attached part, which
would be discarded.  Move the base info to the end of the part,
still inside the part boundary.

Add tests for the exact format of the email signature, and add tests
to ensure that the base info appears before the email signature when
producing a plain-text output, and that it appears before the part
boundary when producing a MIME attachment.

Signed-off-by: Josh Triplett <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: joshtriplett

builtin/log.c

@@ -1042,7 +1042,6 @@ static void make_cover_letter(struct rev_info *rev, int use_stdout,
 	diff_flush(&opts);
 
 	fprintf(rev->diffopt.file, "\n");
-	print_signature(rev->diffopt.file);
 }
 
 static const char *clean_message_id(const char *msg_id)
@@ -1361,7 +1360,7 @@ static void print_bases(struct base_tree_info *bases, FILE *file)
 		return;
 
 	/* Show the base commit */
-	fprintf(file, "base-commit: %s\n", oid_to_hex(&bases->base_commit));
+	fprintf(file, "\nbase-commit: %s\n", oid_to_hex(&bases->base_commit));
 
 	/* Show the prerequisite patches */
 	for (i = bases->nr_patch_id - 1; i >= 0; i--)
@@ -1720,6 +1719,7 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
 		make_cover_letter(&rev, use_stdout,
 				  origin, nr, list, branch_name, quiet);
 		print_bases(&bases, rev.diffopt.file);
+		print_signature(rev.diffopt.file);
 		total++;
 		start_number--;
 	}
@@ -1779,13 +1779,13 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
 		if (!use_stdout)
 			rev.shown_one = 0;
 		if (shown) {
+			print_bases(&bases, rev.diffopt.file);
 			if (rev.mime_boundary)
 				fprintf(rev.diffopt.file, "\n--%s%s--\n\n\n",
 				       mime_boundary_leader,
 				       rev.mime_boundary);
 			else
 				print_signature(rev.diffopt.file);
-			print_bases(&bases, rev.diffopt.file);
 		}
 		if (!use_stdout)
 			fclose(rev.diffopt.file);

t/t4014-format-patch.sh

@@ -754,9 +754,22 @@ test_expect_success 'format-patch --ignore-if-in-upstream HEAD' '
 	git format-patch --ignore-if-in-upstream HEAD
 '
 
+git_version="$(git --version | sed "s/.* //")"
+
+signature() {
+	printf "%s\n%s\n\n" "-- " "${1:-$git_version}"
+}
+
+test_expect_success 'format-patch default signature' '
+	git format-patch --stdout -1 | tail -n 3 >output &&
+	signature >expect &&
+	test_cmp expect output
+'
+
 test_expect_success 'format-patch --signature' '
-	git format-patch --stdout --signature="my sig" -1 >output &&
-	grep "my sig" output
+	git format-patch --stdout --signature="my sig" -1 | tail -n 3 >output &&
+	signature "my sig" >expect &&
+	test_cmp expect output
 '
 
 test_expect_success 'format-patch with format.signature config' '
@@ -1502,12 +1515,12 @@ test_expect_success 'format-patch -o overrides format.outputDirectory' '
 
 test_expect_success 'format-patch --base' '
 	git checkout side &&
-	git format-patch --stdout --base=HEAD~3 -1 >patch &&
-	grep "^base-commit:" patch >actual &&
-	grep "^prerequisite-patch-id:" patch >>actual &&
-	echo "base-commit: $(git rev-parse HEAD~3)" >expected &&
+	git format-patch --stdout --base=HEAD~3 -1 | tail -n 7 >actual &&
+	echo >expected &&
+	echo "base-commit: $(git rev-parse HEAD~3)" >>expected &&
 	echo "prerequisite-patch-id: $(git show --patch HEAD~2 | git patch-id --stable | awk "{print \$1}")" >>expected &&
 	echo "prerequisite-patch-id: $(git show --patch HEAD~1 | git patch-id --stable | awk "{print \$1}")" >>expected &&
+	signature >> expected &&
 	test_cmp expected actual
 '
 
@@ -1605,6 +1618,14 @@ test_expect_success 'format-patch --base overrides format.useAutoBase' '
 	test_cmp expected actual
 '
 
+test_expect_success 'format-patch --base with --attach' '
+	git format-patch --attach=mimemime --stdout --base=HEAD~ -1 >patch &&
+	sed -n -e "/^base-commit:/s/.*/1/p" -e "/^---*mimemime--$/s/.*/2/p" \
+		patch >actual &&
+	test_write_lines 1 2 >expect &&
+	test_cmp expect actual
+'
+
 test_expect_success 'format-patch --pretty=mboxrd' '
 	sp=" " &&
 	cat >msg <<-INPUT_END &&