patch: Use pg_mbcliplen for truncation in text-to-name conversion

The text_name function was truncating its input string to the first
NAMEDATALEN-1 bytes, which is wrong if the string has multi-byte
characters. This patch changes it to use pg_mbcliplen, following
the namein function.
diff --git a/src/backend/utils/adt/varlena.c b/src/backend/utils/adt/varlena.c
index a5592d5..02fe9b4 100644
--- a/src/backend/utils/adt/varlena.c
+++ b/src/backend/utils/adt/varlena.c
@@ -2255,8 +2255,7 @@ text_name(PG_FUNCTION_ARGS)
     len = VARSIZE_ANY_EXHDR(s);

     /* Truncate oversize input */
-    if (len >= NAMEDATALEN)
-        len = NAMEDATALEN - 1;
+    len = pg_mbcliplen(VARDATA_ANY(s), len, NAMEDATALEN - 1);

     result = (Name) palloc(NAMEDATALEN);
     memcpy(NameStr(*result), VARDATA_ANY(s), len);
diff --git a/src/test/regress/expected/name.out b/src/test/regress/expected/name.out
index b359d52..f4b58f1 100644
--- a/src/test/regress/expected/name.out
+++ b/src/test/regress/expected/name.out
@@ -15,6 +15,19 @@ SELECT name 'name string' = name 'name string ' AS "False";
  f
 (1 row)

+-- name truncation with unicode characters
+SELECT length(repeat(U&'\0400', 32)::unknown::name::bytea, 'utf8') as length_from_unknown;
+ length_from_unknown
+---------------------
+                  31
+(1 row)
+
+SELECT length(repeat(U&'\0400', 32)::text::name::bytea, 'utf8') as length_from_text;
+ length_from_text
+------------------
+               31
+(1 row)
+
 --
 --
 --
diff --git a/src/test/regress/sql/name.sql b/src/test/regress/sql/name.sql
index 1c7a671..9f7a5f0 100644
--- a/src/test/regress/sql/name.sql
+++ b/src/test/regress/sql/name.sql
@@ -8,6 +8,10 @@ SELECT name 'name string' = name 'name string' AS "True";

 SELECT name 'name string' = name 'name string ' AS "False";

+-- name truncation with unicode characters
+SELECT length(repeat(U&'\0400', 32)::unknown::name::bytea, 'utf8') as length_from_unknown;
+SELECT length(repeat(U&'\0400', 32)::text::name::bytea, 'utf8') as length_from_text;
+
 --
 --
 --