[Private] class names should be CamelCase

Tests/test_util.py

@@ -65,7 +65,7 @@ def test_deferred_error():
     # Arrange
 
     # Act
-    thing = _util.deferred_error(ValueError("Some error text"))
+    thing = _util.DeferredError(ValueError("Some error text"))
 
     # Assert
     with pytest.raises(ValueError):

src/PIL/Image.py

@@ -50,7 +50,7 @@ except ImportError:
 # Use __version__ instead.
 from . import ImageMode, TiffTags, UnidentifiedImageError, __version__, _plugins
 from ._binary import i32le, o32be, o32le
-from ._util import deferred_error, is_path
+from ._util import DeferredError, is_path
 
 
 def __getattr__(name):
@@ -139,7 +139,7 @@ try:
         )
 
 except ImportError as v:
-    core = deferred_error(ImportError("The _imaging C module is not installed."))
+    core = DeferredError(ImportError("The _imaging C module is not installed."))
     # Explanations for ways that we know we might have an import error
     if str(v).startswith("Module use of python"):
         # The _imaging C module is present, but not compiled for
@@ -613,7 +613,7 @@ class Image:
         # Instead of simply setting to None, we're setting up a
         # deferred error that will better explain that the core image
         # object is gone.
-        self.im = deferred_error(ValueError("Operation on closed image"))
+        self.im = DeferredError(ValueError("Operation on closed image"))
 
     def _copy(self):
         self.load()

src/PIL/ImageCms.py

@@ -26,9 +26,9 @@ try:
 except ImportError as ex:
     # Allow error import for doc purposes, but error out when accessing
     # anything in core.
-    from ._util import deferred_error
+    from ._util import DeferredError
 
-    _imagingcms = deferred_error(ex)
+    _imagingcms = DeferredError(ex)
 
 DESCRIPTION = """
 pyCMS

src/PIL/ImageFont.py

@@ -64,7 +64,7 @@ def __getattr__(name):
     raise AttributeError(f"module '{__name__}' has no attribute '{name}'")
 
 
-class _imagingft_not_installed:
+class _ImagingFtNotInstalled:
     # module placeholder
     def __getattr__(self, id):
         raise ImportError("The _imagingft C module is not installed")
@@ -73,7 +73,7 @@ class _imagingft_not_installed:
 try:
     from . import _imagingft as core
 except ImportError:
-    core = _imagingft_not_installed()
+    core = _ImagingFtNotInstalled()
 
 
 # FIXME: add support for pilfont2 format (see FontFile.py)

src/PIL/PyAccess.py

@@ -39,9 +39,9 @@ try:
 except ImportError as ex:
     # Allow error import for doc purposes, but error out when accessing
     # anything in core.
-    from ._util import deferred_error
+    from ._util import DeferredError
 
-    FFI = ffi = deferred_error(ex)
+    FFI = ffi = DeferredError(ex)
 
 logger = logging.getLogger(__name__)
 

src/PIL/_util.py

@@ -11,7 +11,7 @@ def is_directory(f):
     return is_path(f) and os.path.isdir(f)
 
 
-class deferred_error:
+class DeferredError:
     def __init__(self, ex):
         self.ex = ex