Remove unused error classes. (#595)

* Remove unused error classes.

* Remove AuthenticationError, ExportError, FetchError.

changelog.txt

@@ -21,6 +21,7 @@ Removed
  - The ``syncutil.copytree`` method (#581).
  - All Crawlers, including ``RegexFileCrawler``, ``MainCrawler``, ``MasterCrawler``, ``SignacProjectCrawler``, and ``BaseCrawler``, in addition to all associated functionality in indexing.py (#580).
  - The cite.py module (#594).
+ - The following types of exceptions: ``AuthenticationError``, ``ExportError`, ``FetchError`` (#595).
 
 Version 1
 =========

signac/common/errors.py

@@ -9,28 +9,3 @@ class ConfigError(Error, RuntimeError):
     """Error with parsing or reading a configuration file."""
 
     pass
-
-
-# this class is only used by deprecated features
-class AuthenticationError(Error, RuntimeError):
-    """Authentication error."""
-
-    def __str__(self):
-        if len(self.args) > 0:
-            return f"Failed to authenticate with host '{self.args[0]}'."
-        else:
-            return "Failed to authenticate with host."
-
-
-# this class is only used by deprecated features
-class ExportError(Error, RuntimeError):
-    """Error exporting documents to a mirror."""
-
-    pass
-
-
-# this class is only used by deprecated features
-class FetchError(FileNotFoundError):
-    """Error in fetching data."""
-
-    pass

signac/errors.py

@@ -7,7 +7,7 @@
 # exceptions that are relevant beyond a single module. This top-level errors
 # module is used to expose user-facing exception classes.
 
-from .common.errors import AuthenticationError, ConfigError, ExportError, FetchError
+from .common.errors import ConfigError
 from .contrib.errors import (
     DestinationExistsError,
     IncompatibleSchemaVersion,
@@ -59,13 +59,10 @@ def __str__(self):
 
 
 __all__ = [
-    "AuthenticationError",
     "ConfigError",
     "DestinationExistsError",
     "DocumentSyncConflict",
     "Error",
-    "ExportError",
-    "FetchError",
     "FileSyncConflict",
     "IncompatibleSchemaVersion",
     "InvalidKeyError",