Raise proper validation errors from Int and Float as well as Decimal.issue16

Fix the doctests that pointed out this should be done.

5 files changed, 46 insertions, 7 deletions

diff --git a/CHANGES.rst b/CHANGES.rst
index d39da58..01bb7c1 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -46,6 +46,10 @@
   attribute that is set to the field that raised the exception and the
   value that failed validation.
 
+- ``Float``, ``Int`` and ``Decimal`` fields raise ``ValidationError``
+  subclasses for literals that cannot be parsed. These subclasses also
+  subclass ``ValueError`` for backwards compatibility.
+
 - Add a new exception ``SchemaNotCorrectlyImplemented``, a subclass of
   ``WrongContainedType`` that is raised by the ``Object`` field. It
   has a dictionary (``schema_errors``) mapping invalid schema
diff --git a/docs/fields.rst b/docs/fields.rst
index 7799441..7ebabaf 100644
--- a/docs/fields.rst
+++ b/docs/fields.rst
@@ -101,7 +101,27 @@ Conversion from Unicode:
    >>> f.fromUnicode("1.25.6") #doctest: +IGNORE_EXCEPTION_DETAIL
    Traceback (most recent call last):
    ...
-   ValueError: invalid literal for float(): 1.25.6
+   InvalidFloatLiteral: invalid literal for float(): 1.25.6
+
+Int
+###
+
+:class:`zope.schema.Int` fields contain binary data, represented
+as a a Python ``int``.
+
+Conversion from Unicode:
+
+.. doctest::
+
+   >>> from zope.schema import Int
+   >>> f = Int()
+   >>> f.fromUnicode("1")
+   1
+   >>> f.fromUnicode("1.25.6") #doctest: +IGNORE_EXCEPTION_DETAIL
+   Traceback (most recent call last):
+   ...
+   InvalidIntLiteral: invalid literal for int() with base 10: 1.25.6
+
 
 Decimal
 #######
@@ -123,7 +143,7 @@ Conversion from Unicode:
    >>> f.fromUnicode("1.25.6")
    Traceback (most recent call last):
    ...
-   ValueError: invalid literal for Decimal(): 1.25.6
+   InvalidDecimalLiteral: invalid literal for Decimal(): 1.25.6
 
 Datetime
 ########
diff --git a/src/zope/schema/_bootstrapfields.py b/src/zope/schema/_bootstrapfields.py
index c96c7d8..6501310 100644
--- a/src/zope/schema/_bootstrapfields.py
+++ b/src/zope/schema/_bootstrapfields.py
@@ -19,6 +19,7 @@ from zope.interface import Attribute
 from zope.interface import providedBy
 from zope.interface import implementer
 
+from zope.schema._bootstrapinterfaces import ValidationError
 from zope.schema._bootstrapinterfaces import ConstraintNotSatisfied
 from zope.schema._bootstrapinterfaces import IContextAwareDefaultFactory
 from zope.schema._bootstrapinterfaces import IFromUnicode
@@ -440,6 +441,9 @@ class Bool(Field):
         self.validate(v)
         return v
 
+class InvalidIntLiteral(ValueError, ValidationError):
+    """Invalid int literal."""
+
 
 @implementer(IFromUnicode)
 class Int(Orderable, Field):
@@ -458,8 +462,11 @@ class Int(Orderable, Field):
         >>> f.fromUnicode("125.6") #doctest: +IGNORE_EXCEPTION_DETAIL
         Traceback (most recent call last):
         ...
-        ValueError: invalid literal for int(): 125.6
+        InvalidIntLiteral: invalid literal for int(): 125.6
         """
-        v = int(str)
+        try:
+            v = int(str)
+        except ValueError as v:
+            raise InvalidIntLiteral(*v.args).with_field_and_value(self, str)
         self.validate(v)
         return v
diff --git a/src/zope/schema/_field.py b/src/zope/schema/_field.py
index 21edeb6..807ca48 100644
--- a/src/zope/schema/_field.py
+++ b/src/zope/schema/_field.py
@@ -185,6 +185,10 @@ class ASCIILine(ASCII):
         return '\n' not in value
 
 
+class InvalidFloatLiteral(ValueError, ValidationError):
+    """Raised by Float fields."""
+
+
 @implementer(IFloat, IFromUnicode)
 class Float(Orderable, Field):
     __doc__ = IFloat.__doc__
@@ -196,7 +200,10 @@ class Float(Orderable, Field):
     def fromUnicode(self, uc):
         """ See IFromUnicode.
         """
-        v = float(uc)
+        try:
+            v = float(uc)
+        except ValueError as v:
+            raise InvalidFloatLiteral(*v.args).with_field_and_value(self, uc)
         self.validate(v)
         return v
 
diff --git a/tox.ini b/tox.ini
index 8012429..184397e 100644
--- a/tox.ini
+++ b/tox.ini
@@ -7,9 +7,10 @@ envlist =
 
 [testenv]
 deps =
-    .[test]
+    .[test,docs]
 commands =
     zope-testrunner --test-path=src
+    sphinx-build -b doctest -d {envdir}/.cache/doctrees docs {envdir}/.cache/doctest
 
 [testenv:coverage]
 usedevelop = true
@@ -24,7 +25,7 @@ deps =
 
 [testenv:docs]
 basepython =
-    python2.7
+    python3.6
 commands =
     sphinx-build -b html -d docs/_build/doctrees docs docs/_build/html
     sphinx-build -b doctest -d docs/_build/doctrees docs docs/_build/doctest