[Breakable] ColumnList is reverted to be a slice.

ColumnList(...) -> ColumnList{...}
IColumnList is removed.

postgres/columns.go

@@ -5,12 +5,8 @@ import "github.com/go-jet/jet/internal/jet"
 // Column is common column interface for all types of columns.
 type Column = jet.ColumnExpression
 
-// IColumnList is used to store list of columns for later reuse as single projection or
-// column list for UPDATE and INSERT statement.
-type IColumnList = jet.IColumnList
-
 // ColumnList function returns list of columns that be used as projection or column list for UPDATE and INSERT statement.
-var ColumnList = jet.ColumnList
+type ColumnList = jet.ColumnList
 
 // ColumnBool is interface for SQL boolean columns.
 type ColumnBool = jet.ColumnBool

postgres/insert_statement_test.go

@@ -26,7 +26,7 @@ INSERT INTO db.table1 (col1) VALUES
 }
 
 func TestInsertWithColumnList(t *testing.T) {
-	columnList := ColumnList(table3ColInt, table3StrCol)
+	columnList := ColumnList{table3ColInt, table3StrCol}
 
 	assertStatementSql(t, table3.INSERT(columnList).VALUES(1, 3), `
 INSERT INTO db.table3 (col_int, col2) VALUES

postgres/select_statement_test.go

@@ -9,7 +9,7 @@ func TestInvalidSelect(t *testing.T) {
 }
 
 func TestSelectColumnList(t *testing.T) {
-	columnList := ColumnList(table2ColInt, table2ColFloat, table3ColInt)
+	columnList := ColumnList{table2ColInt, table2ColFloat, table3ColInt}
 
 	assertStatementSql(t, SELECT(columnList).FROM(table2), `
 SELECT table2.col_int AS "table2.col_int",