Refactor validator return type to support warnings via ValidationResult wrapper (#1479)

src/hdmf/validate/errors.py

@@ -85,6 +85,78 @@ def __eq__(self, other):
         return hash(self) == hash(other)
 
 
+class ValidationWarning:
+
+    @docval({'name': 'name', 'type': str, 'doc': 'the name of the component that is erroneous'},
+            {'name': 'reason', 'type': str, 'doc': 'the reason for the warning'},
+            {'name': 'location', 'type': str, 'doc': 'the location of the warning', 'default': None})
+    def __init__(self, **kwargs):
+        self.__name = getargs('name', kwargs)
+        self.__reason = getargs('reason', kwargs)
+        self.__location = getargs('location', kwargs)
+
+    @property
+    def name(self):
+        return self.__name
+
+    @property
+    def reason(self):
+        return self.__reason
+
+    @property
+    def location(self):
+        return self.__location
+
+    @location.setter
+    def location(self, loc):
+        self.__location = loc
+
+    def __str__(self):
+        return self.__format_str(self.name, self.location, self.reason)
+
+    @staticmethod
+    def __format_str(name, location, reason):
+        if location is not None:
+            return "%s (%s): %s" % (name, location, reason)
+        else:
+            return "%s: %s" % (name, reason)
+
+    def __repr__(self):
+        return self.__str__()
+
+    def __hash__(self):
+        return hash(self.__equatable_str())
+
+    def __equatable_str(self):
+        if self.location is not None:
+            equatable_name = self.name.split('/')[-1]
+        else:
+            equatable_name = self.name
+        return self.__format_str(equatable_name, self.location, self.reason)
+
+    def __eq__(self, other):
+        return hash(self) == hash(other)
+
+
+class ValidationResult:
+
+    def __init__(self, errors = None, warnings = None):
+        self.errors = list(errors) if errors is not None else []
+        self.warnings = list(warnings) if errors is not None else []
+
+    def __iter__(self):
+        return iter(self.errors)
+
+    def __len__(self):
+        return len(self.errors)
+
+    def __bool__(self):
+        return bool(self.errors)
+
+    def __getitem__(self, i):
+        return self.errors[i]
+
+
 class DtypeError(Error):
 
     @docval({'name': 'name', 'type': str, 'doc': 'the name of the component that is erroneous'},

src/hdmf/validate/validator.py

@@ -7,7 +7,7 @@
 import numpy as np
 
 from .errors import Error, DtypeError, MissingError, MissingDataType, ShapeError, IllegalLinkError, IncorrectDataType
-from .errors import ExpectedArrayError, IncorrectQuantityError
+from .errors import ExpectedArrayError, IncorrectQuantityError, ValidationResult
 from ..build import GroupBuilder, DatasetBuilder, LinkBuilder, ReferenceBuilder
 from ..build.builders import BaseBuilder
 from ..spec import Spec, AttributeSpec, GroupSpec, DatasetSpec, RefSpec, LinkSpec
@@ -325,7 +325,7 @@ def get_validator(self, **kwargs):
             raise ValueError(msg)
 
     @docval({'name': 'builder', 'type': BaseBuilder, 'doc': 'the builder to validate'},
-            returns="a list of errors found", rtype=list)
+            returns="a list of errors found", rtype=(list, ValidationResult))
     def validate(self, **kwargs):
         """Validate a builder against a Spec
 
@@ -338,7 +338,8 @@ def validate(self, **kwargs):
             msg = "builder must have data type defined with attribute '%s'" % self.__type_key
             raise ValueError(msg)
         validator = self.get_validator(dt)
-        return validator.validate(builder)
+        errors_list = validator.validate(builder)
+        return ValidationResult(errors=errors_list, warnings=[])
 
 
 class Validator(metaclass=ABCMeta):