feat(optimizer)!: annotate types for Snowflake BIT_LENGTH function

Author: fivetran-BradfordPaskewitz

sqlglot/dialects/snowflake.py

@@ -532,6 +532,7 @@ class Snowflake(Dialect):
         exp.DataType.Type.INT: {
             *Dialect.TYPE_TO_EXPRESSIONS[exp.DataType.Type.INT],
             exp.Length,
+            exp.BitLength,
         },
         exp.DataType.Type.VARCHAR: {
             *Dialect.TYPE_TO_EXPRESSIONS[exp.DataType.Type.VARCHAR],

sqlglot/expressions.py

@@ -6875,6 +6875,10 @@ class Length(Func):
     _sql_names = ["LENGTH", "LEN", "CHAR_LENGTH", "CHARACTER_LENGTH"]
 
 
+class BitLength(Func):
+    pass
+
+
 class Levenshtein(Func):
     arg_types = {
         "this": True,

tests/dialects/test_snowflake.py

@@ -34,6 +34,8 @@ def test_snowflake(self):
             "SELECT BASE64_DECODE_BINARY('SGVsbG8=', 'ABCDEFGHwxyz0123456789+/')"
         )
 
+        self.validate_identity("SELECT BIT_LENGTH('abc')")
+        self.validate_identity("SELECT BIT_LENGTH(x'A1B2')")
         self.validate_identity("SELECT {*} FROM my_table")
         self.validate_identity("SELECT {my_table.*} FROM my_table")
         self.validate_identity("SELECT {* ILIKE 'col1%'} FROM my_table")

tests/fixtures/optimizer/annotate_functions.sql

@@ -1563,6 +1563,18 @@ VARCHAR;
 BASE64_DECODE_BINARY('SGVsbG8=');
 BINARY;
 
+# dialect: snowflake
+BIT_LENGTH('abc');
+INT;
+
+# dialect: snowflake
+BIT_LENGTH(tbl.str_col);
+INT;
+
+# dialect: snowflake
+BIT_LENGTH(tbl.bin_col);
+INT;
+
 # dialect: snowflake
 CHARINDEX('world', 'hello world');
 INT;