Merge pull request #1089 from suketa/refactor-scalar-function-supported-types

Refactor ScalarFunction to use SUPPORTED_RETURN_TYPES constant

Author: suketa

lib/duckdb/scalar_function.rb

@@ -3,6 +3,28 @@
 module DuckDB
   # DuckDB::ScalarFunction encapsulates DuckDB's scalar function
   class ScalarFunction
+    # Supported return types for scalar functions
+    SUPPORTED_RETURN_TYPES = %i[
+      bigint
+      blob
+      boolean
+      date
+      double
+      float
+      integer
+      smallint
+      time
+      timestamp
+      tinyint
+      ubigint
+      uinteger
+      usmallint
+      utinyint
+      varchar
+    ].freeze
+
+    private_constant :SUPPORTED_RETURN_TYPES
+
     # Sets the return type for the scalar function.
     # Currently supports BIGINT, BLOB, BOOLEAN, DATE, DOUBLE, FLOAT, INTEGER, SMALLINT, TIME, TIMESTAMP, TINYINT,
     # UBIGINT, UINTEGER, USMALLINT, UTINYINT, and VARCHAR types.
@@ -13,13 +35,10 @@ class ScalarFunction
     def return_type=(logical_type)
       raise DuckDB::Error, 'logical_type must be a DuckDB::LogicalType' unless logical_type.is_a?(DuckDB::LogicalType)
 
-      # Check if the type is supported
-      supported_types = %i[bigint blob boolean date double float integer smallint time timestamp tinyint ubigint
-                           uinteger usmallint utinyint varchar]
-      unless supported_types.include?(logical_type.type)
+      unless SUPPORTED_RETURN_TYPES.include?(logical_type.type)
+        type_list = SUPPORTED_RETURN_TYPES.map(&:upcase).join(', ')
         raise DuckDB::Error,
-              'Only BIGINT, BLOB, BOOLEAN, DATE, DOUBLE, FLOAT, INTEGER, SMALLINT, TIME, TIMESTAMP, TINYINT, ' \
-              'UBIGINT, UINTEGER, USMALLINT, UTINYINT, and VARCHAR return types are currently supported'
+              "Only #{type_list} return types are currently supported"
       end
 
       _set_return_type(logical_type)