Completely change errors (make one class for each)

telethon/errors/common.py

@@ -0,0 +1,37 @@
+"""Errors not related to the Telegram API itself"""
+
+
+class ReadCancelledError(Exception):
+    """Occurs when a read operation was cancelled"""
+    def __init__(self):
+        super().__init__(self, 'The read operation was cancelled.')
+
+
+class InvalidParameterError(Exception):
+    """Occurs when an invalid parameter is given, for example,
+    when either A or B are required but none is given"""
+
+
+class TypeNotFoundError(Exception):
+    """Occurs when a type is not found, for example,
+    when trying to read a TLObject with an invalid constructor code"""
+
+    def __init__(self, invalid_constructor_id):
+        super().__init__(
+            self, 'Could not find a matching Constructor ID for the TLObject '
+            'that was supposed to be read with ID {}. Most likely, a TLObject '
+            'was trying to be read when it should not be read.'
+            .format(hex(invalid_constructor_id)))
+
+        self.invalid_constructor_id = invalid_constructor_id
+
+
+class InvalidChecksumError(Exception):
+    def __init__(self, checksum, valid_checksum):
+        super().__init__(
+            self,
+            'Invalid checksum ({} when {} was expected). This packet should be skipped.'
+            .format(checksum, valid_checksum))
+
+        self.checksum = checksum
+        self.valid_checksum = valid_checksum