never raise ValueError - always use hyperframe custom types (#147)

Author: Kriechi

HISTORY.rst

@@ -16,6 +16,13 @@ Release History
 - Fixed unchecked frame length for ``WindowUpdateFrame``. It now correctly raises ``InvalidFrameError``.
 - Fixed window increment value range validation. It must be 1 <= increment <= 2^31-1.
 - Fixed parsing of ``SettingsFrame`` with mutual exclusion of ACK flag and payload.
+- Invalid frames with wrong stream id (zero vs. non-zero) now raise ``InvalidFrameError``, not
+  ``ValueError``. Note that ``InvalidFrameError`` is a ``ValueError`` subclass.
+- Invalid SETTINGS frames (non-empty but ACK) now raise ``InvalidFrameError``, not
+  ``ValueError``. Note that ``InvalidFrameError`` is a ``ValueError`` subclass.
+- Invalid ALTSVC frames with non-bytestring field or origin now raise ``InvalidFrameError``, not
+  ``ValueError``. Note that ``InvalidFrameError`` is a ``ValueError`` subclass.
+
 
 **Other Changes**
 

hyperframe/frame.py

@@ -68,10 +68,10 @@ def __init__(self, stream_id, flags=()):
 
         if (not self.stream_id and
            self.stream_association == _STREAM_ASSOC_HAS_STREAM):
-            raise ValueError('Stream ID must be non-zero')
+            raise InvalidFrameError('Stream ID must be non-zero')
         if (self.stream_id and
            self.stream_association == _STREAM_ASSOC_NO_STREAM):
-            raise ValueError('Stream ID must be zero')
+            raise InvalidFrameError('Stream ID must be zero')
 
     def __repr__(self):
         flags = ", ".join(self.flags) or "None"
@@ -415,7 +415,9 @@ def __init__(self, stream_id=0, settings=None, **kwargs):
         super(SettingsFrame, self).__init__(stream_id, **kwargs)
 
         if settings and "ACK" in kwargs.get("flags", ()):
-            raise ValueError("Settings must be empty if ACK flag is set.")
+            raise InvalidFrameError(
+                "Settings must be empty if ACK flag is set."
+            )
 
         #: A dictionary of the setting type byte to the value of the setting.
         self.settings = settings or {}
@@ -762,9 +764,9 @@ def __init__(self, stream_id, origin=b'', field=b'', **kwargs):
         super(AltSvcFrame, self).__init__(stream_id, **kwargs)
 
         if not isinstance(origin, bytes):
-            raise ValueError("AltSvc origin must be bytestring.")
+            raise InvalidFrameError("AltSvc origin must be bytestring.")
         if not isinstance(field, bytes):
-            raise ValueError("AltSvc field must be a bytestring.")
+            raise InvalidFrameError("AltSvc field must be a bytestring.")
         self.origin = origin
         self.field = field