Add `isInconsistent` property hook to all constructed types (#170)

Added `isInconsistent` property to all constructed types. This property
conceptually replaces `verifySizeSpec` method to serve a more general
purpose e.g. ensuring all required fields are in a good shape. By
default this check invokes subtype constraints verification and is run
by codecs on value de/serialisation.

2 files changed, 22 insertions, 3 deletions

diff --git a/pyasn1/type/base.py b/pyasn1/type/base.py
index 21e4041..1fd69f9 100644
--- a/pyasn1/type/base.py
+++ b/pyasn1/type/base.py
@@ -655,8 +655,23 @@ class ConstructedAsn1Type(Asn1Type):
 
         return clone
 
-    def verifySizeSpec(self):
-        self.sizeSpec(self)
+    @property
+    def isInconsistent(self):
+        """Run necessary checks to ensure object consistency.
+
+        Default action is to verify |ASN.1| object against constraints imposed
+        by `subtypeSpec`.
+
+        Raises
+        ------
+        :py:class:`~pyasn1.error.PyAsn1tError` on any inconsistencies found
+        """
+        try:
+            self.sizeSpec(self)
+
+        except error.PyAsn1Error:
+            exc = sys.exc_info()[1]
+            return exc
 
     def getComponentByPosition(self, idx):
         raise error.PyAsn1Error('Method not implemented')
@@ -679,5 +694,9 @@ class ConstructedAsn1Type(Asn1Type):
     def getComponentType(self):
         return self.componentType
 
+    def verifySizeSpec(self):
+        self.sizeSpec(self)
+
+
 # Backward compatibility
 AbstractConstructedAsn1Item = ConstructedAsn1Type
diff --git a/pyasn1/type/univ.py b/pyasn1/type/univ.py
index b39c533..4f305f6 100644
--- a/pyasn1/type/univ.py
+++ b/pyasn1/type/univ.py
@@ -3004,7 +3004,7 @@ class Choice(Set):
         if self._currentIdx is not None:
             yield self.componentType[self._currentIdx].getName(), self[self._currentIdx]
 
-    def verifySizeSpec(self):
+    def checkConsistency(self):
         if self._currentIdx is None:
             raise error.PyAsn1Error('Component not chosen')