Allow column sql types to be tested from the table handler

issue9645
review312421002

CHANGELOG

@@ -1,3 +1,4 @@
+* Allow column sql types to be tested from the table handler
 * Add support for database connection parameters to configuration URI
 * Use immutable datastructures for Dict and MultiSelection fields
 * Skip warnings for non-interactive operations

trytond/backend/postgresql/table.py

@@ -221,6 +221,18 @@ class TableHandler(TableHandlerInterface):
             'ALTER "' + column_name + '" TYPE ' + column_type)
         self._update_definitions(columns=True)
 
+    def column_is_type(self, column_name, type_, *, size=-1):
+        db_type = self._columns[column_name]['typname'].upper()
+
+        database = Transaction().database
+        base_type = database.sql_type(type_).base.upper()
+        if base_type == 'VARCHAR':
+            same_size = self._columns[column_name]['size'] == size
+        else:
+            same_size = True
+
+        return base_type == db_type and same_size
+
     def db_default(self, column_name, value):
         if value in [True, False]:
             test = str(value).lower()

trytond/backend/sqlite/table.py

@@ -138,7 +138,7 @@ class TableHandler(TableHandlerInterface):
                     size = match.group(3) and int(match.group(3)) or 0
                 else:
                     typname = type_.upper()
-                    size = -1
+                    size = None
                 self._columns[column] = {
                     'notnull': notnull,
                     'hasdef': hasdef,
@@ -170,6 +170,18 @@ class TableHandler(TableHandlerInterface):
     def alter_type(self, column_name, column_type):
         self._recreate_table({column_name: {'typname': column_type}})
 
+    def column_is_type(self, column_name, type_, *, size=-1):
+        db_type = self._columns[column_name]['typname'].upper()
+
+        database = Transaction().database
+        base_type = database.sql_type(type_).base.upper()
+        if base_type == 'VARCHAR':
+            same_size = self._columns[column_name]['size'] == size
+        else:
+            same_size = True
+
+        return base_type == db_type and same_size
+
     def db_default(self, column_name, value):
         warnings.warn('Unable to set default on column with SQLite backend')
 

trytond/backend/table.py

@@ -84,6 +84,18 @@ class TableHandlerInterface(object):
         '''
         raise NotImplementedError
 
+    def column_is_type(self, column_name, type_, *, size=-1):
+        '''
+        Return True if the column is of type type_
+
+        :param column_name: the column name
+        :param type_: the generic name of the type
+        :param size: if `type` is VARCHAR you can specify its size.
+                     Defaults to -1 which will won't match any size
+        :return: a boolean
+        '''
+        raise NotImplementedError
+
     def db_default(self, column_name, value):
         '''
         Set a default on a column