update-ref --stdin: improve error messages for invalid values

If an invalid value is passed to "update-ref --stdin" as <oldvalue> or
<newvalue>, include the command and the name of the reference at the
beginning of the error message.  Update the tests accordingly.

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/update-ref.c

@@ -35,20 +35,22 @@ static struct ref_update *update_alloc(void)
 	return update;
 }
 
-static void update_store_new_sha1(struct ref_update *update,
+static void update_store_new_sha1(const char *command,
+				  struct ref_update *update,
 				  const char *newvalue)
 {
 	if (*newvalue && get_sha1(newvalue, update->new_sha1))
-		die("invalid new value for ref %s: %s",
-		    update->ref_name, newvalue);
+		die("%s %s: invalid new value: %s",
+		    command, update->ref_name, newvalue);
 }
 
-static void update_store_old_sha1(struct ref_update *update,
+static void update_store_old_sha1(const char *command,
+				  struct ref_update *update,
 				  const char *oldvalue)
 {
 	if (*oldvalue && get_sha1(oldvalue, update->old_sha1))
-		die("invalid old value for ref %s: %s",
-		    update->ref_name, oldvalue);
+		die("%s %s: invalid old value: %s",
+		    command, update->ref_name, oldvalue);
 
 	/* We have an old value if non-empty, or if empty without -z */
 	update->have_old = *oldvalue || line_termination;
@@ -165,12 +167,12 @@ static const char *parse_cmd_update(struct strbuf *input, const char *next)
 		die("update line missing <ref>");
 
 	if (!parse_next_arg(input, &next, &newvalue))
-		update_store_new_sha1(update, newvalue.buf);
+		update_store_new_sha1("update", update, newvalue.buf);
 	else
 		die("update %s missing <newvalue>", update->ref_name);
 
 	if (!parse_next_arg(input, &next, &oldvalue)) {
-		update_store_old_sha1(update, oldvalue.buf);
+		update_store_old_sha1("update", update, oldvalue.buf);
 		if (*next != line_termination)
 			die("update %s has extra input: %s", update->ref_name, next);
 	} else if (!line_termination)
@@ -191,7 +193,7 @@ static const char *parse_cmd_create(struct strbuf *input, const char *next)
 		die("create line missing <ref>");
 
 	if (!parse_next_arg(input, &next, &newvalue))
-		update_store_new_sha1(update, newvalue.buf);
+		update_store_new_sha1("create", update, newvalue.buf);
 	else
 		die("create %s missing <newvalue>", update->ref_name);
 
@@ -216,7 +218,7 @@ static const char *parse_cmd_delete(struct strbuf *input, const char *next)
 		die("delete line missing <ref>");
 
 	if (!parse_next_arg(input, &next, &oldvalue)) {
-		update_store_old_sha1(update, oldvalue.buf);
+		update_store_old_sha1("delete", update, oldvalue.buf);
 		if (update->have_old && is_null_sha1(update->old_sha1))
 			die("delete %s given zero old value", update->ref_name);
 	} else if (!line_termination)
@@ -240,7 +242,7 @@ static const char *parse_cmd_verify(struct strbuf *input, const char *next)
 		die("verify line missing <ref>");
 
 	if (!parse_next_arg(input, &next, &value)) {
-		update_store_old_sha1(update, value.buf);
+		update_store_old_sha1("verify", update, value.buf);
 		hashcpy(update->new_sha1, update->old_sha1);
 	} else if (!line_termination)
 		die("verify %s missing [<oldvalue>] NUL", update->ref_name);

t/t1400-update-ref.sh

@@ -518,14 +518,14 @@ test_expect_success 'stdin update ref fails with wrong old value' '
 test_expect_success 'stdin update ref fails with bad old value' '
 	echo "update $c $m does-not-exist" >stdin &&
 	test_must_fail git update-ref --stdin <stdin 2>err &&
-	grep "fatal: invalid old value for ref $c: does-not-exist" err &&
+	grep "fatal: update $c: invalid old value: does-not-exist" err &&
 	test_must_fail git rev-parse --verify -q $c
 '
 
 test_expect_success 'stdin create ref fails with bad new value' '
 	echo "create $c does-not-exist" >stdin &&
 	test_must_fail git update-ref --stdin <stdin 2>err &&
-	grep "fatal: invalid new value for ref $c: does-not-exist" err &&
+	grep "fatal: create $c: invalid new value: does-not-exist" err &&
 	test_must_fail git rev-parse --verify -q $c
 '
 
@@ -840,14 +840,14 @@ test_expect_success 'stdin -z update ref fails with wrong old value' '
 test_expect_success 'stdin -z update ref fails with bad old value' '
 	printf $F "update $c" "$m" "does-not-exist" >stdin &&
 	test_must_fail git update-ref -z --stdin <stdin 2>err &&
-	grep "fatal: invalid old value for ref $c: does-not-exist" err &&
+	grep "fatal: update $c: invalid old value: does-not-exist" err &&
 	test_must_fail git rev-parse --verify -q $c
 '
 
 test_expect_success 'stdin -z create ref fails with bad new value' '
 	printf $F "create $c" "does-not-exist" >stdin &&
 	test_must_fail git update-ref -z --stdin <stdin 2>err &&
-	grep "fatal: invalid new value for ref $c: does-not-exist" err &&
+	grep "fatal: create $c: invalid new value: does-not-exist" err &&
 	test_must_fail git rev-parse --verify -q $c
 '