Add bytes option to array_join.

The `array_join` function can now also be used to join bytes into a
single byte-string.

docs/stdlib/array.rst

@@ -33,7 +33,7 @@ Arrays
       - Finds the index of an element in the array.
 
     * - :eql:func:`array_join`
-      - Renders an array to a string.
+      - Renders an array to a string or byte-string.
 
     * - :eql:func:`array_fill`
       - :eql:func-desc:`array_fill`
@@ -313,10 +313,12 @@ Reference
 
 
 .. eql:function:: std::array_join(array: array<str>, delimiter: str) -> str
+                  std::array_join(array: array<bytes>, \
+                                  delimiter: bytes) -> bytes
 
     :index: join array_to_string implode
 
-    Renders an array to a string.
+    Renders an array to a string or byte-string.
 
     Join a string array into a single string using a specified *delimiter*:
 
@@ -325,6 +327,14 @@ Reference
         db> select array_join(['one', 'two', 'three'], ', ');
         {'one, two, three'}
 
+    Similarly, an array of :eql:type:`bytes` can be joined as a single value
+    using a specified *delimiter*:
+
+    .. code-block:: edgeql-repl
+
+        db> select array_join([b'\x01', b'\x02', b'\x03'], b'\xff');
+        {b'\x01\xff\x02\xff\x03'}
+
 
 ----------
 

edb/buildmeta.py

@@ -55,7 +55,7 @@
 
 
 # Increment this whenever the database layout or stdlib changes.
-EDGEDB_CATALOG_VERSION = 2024_02_20_00_00
+EDGEDB_CATALOG_VERSION = 2024_02_23_00_00
 EDGEDB_MAJOR_VERSION = 5
 
 

edb/lib/std/30-arrayfuncs.edgeql

@@ -112,6 +112,20 @@ std::array_join(array: array<std::str>, delimiter: std::str) -> std::str
 };
 
 
+CREATE FUNCTION
+std::array_join(array: array<std::bytes>, delimiter: std::bytes) -> std::bytes
+{
+    CREATE ANNOTATION std::description := 'Render an array to a byte-string.';
+    SET volatility := 'Immutable';
+    USING SQL $$
+    SELECT
+        COALESCE (string_agg(el, "delimiter"), '\x')
+    FROM
+        (SELECT unnest("array") AS el) AS t
+    $$;
+};
+
+
 ## Array operators
 
 

tests/test_edgeql_functions.py

@@ -3289,6 +3289,43 @@ async def test_edgeql_functions_array_join_01(self):
             [''],
         )
 
+    async def test_edgeql_functions_array_join_02(self):
+        await self.assert_query_result(
+            r'''SELECT array_join(['one', 'two', 'three'], {', ', '@!'});''',
+            {'one, two, three', 'one@!two@!three'},
+        )
+
+    async def test_edgeql_functions_array_join_03(self):
+        await self.assert_query_result(
+            r'''SELECT array_join([b'one', b'two', b'three'], b', ');''',
+            [base64.b64encode(b'one, two, three').decode()],
+            [b'one, two, three'],
+        )
+
+        await self.assert_query_result(
+            r'''SELECT array_join([b'one', b'two', b'three'], b'');''',
+            [base64.b64encode(b'onetwothree').decode()],
+            [b'onetwothree'],
+        )
+
+        await self.assert_query_result(
+            r'''SELECT array_join(<array<bytes>>[], b', ');''',
+            [base64.b64encode(b'').decode()],
+            [b''],
+        )
+
+    async def test_edgeql_functions_array_join_04(self):
+        await self.assert_query_result(
+            r'''
+            SELECT array_join([b'one', b'two', b'three'], {b', ', b'@!'});
+            ''',
+            {
+                base64.b64encode(b'one, two, three').decode(),
+                base64.b64encode(b'one@!two@!three').decode(),
+            },
+            {b'one, two, three', b'one@!two@!three'},
+        )
+
     async def test_edgeql_functions_str_split_01(self):
         await self.assert_query_result(
             r'''SELECT str_split('one, two, three', ', ');''',