Field name are customizable

CHANGES.rst

@@ -20,6 +20,8 @@ Unreleased
     :class:`~validators.ValidationError` or
     :class:`~validators.StopValidation` to make a validation fail.
     :issue:`445`
+-   Fields can have a HTML name different than their python name.
+    :issue:`205` :pr:`601`
 
 
 Version 2.3.1

src/wtforms/fields/core.py

@@ -88,8 +88,8 @@ def __init__(
             If provided, a dictionary which provides default keywords that
             will be given to the widget at render time.
         :param name:
-            The name of this field, passed by the enclosing form during its
-            construction. You should never pass this value yourself.
+            The HTML name of this field. The default value is the python
+            field name.
         :param _form:
             The form holding this field. It is passed by the form itself during
             construction. You should never pass this value yourself.
@@ -375,10 +375,11 @@ class UnboundField:
     _formfield = True
     creation_counter = 0
 
-    def __init__(self, field_class, *args, **kwargs):
+    def __init__(self, field_class, *args, name=None, **kwargs):
         UnboundField.creation_counter += 1
         self.field_class = field_class
         self.args = args
+        self.name = name
         self.kwargs = kwargs
         self.creation_counter = UnboundField.creation_counter
         validators = kwargs.get("validators")

src/wtforms/form.py

@@ -42,7 +42,8 @@ def __init__(self, fields, prefix="", meta=_default_meta):
             extra_fields.extend(self._csrf.setup_form(self))
 
         for name, unbound_field in itertools.chain(fields, extra_fields):
-            options = dict(name=name, prefix=prefix, translations=translations)
+            field_name = unbound_field.name or name
+            options = dict(name=field_name, prefix=prefix, translations=translations)
             field = meta.bind_field(self, unbound_field, options)
             self._fields[name] = field
 
@@ -108,8 +109,8 @@ def process(self, formdata=None, obj=None, data=None, **kwargs):
         for name, field in self._fields.items():
             if obj is not None and hasattr(obj, name):
                 field.process(formdata, getattr(obj, name))
-            elif name in kwargs:
-                field.process(formdata, kwargs[name])
+            elif field.short_name in kwargs:
+                field.process(formdata, kwargs[field.short_name])
             else:
                 field.process(formdata)
 

tests/test_fields.py

@@ -276,6 +276,43 @@ def test_check_validators(self):
         ):
             Field(validators=[v2])
 
+    def test_custom_name(self):
+        class F(Form):
+            foo = StringField(name="bar", default="defaultvalue")
+
+        class Objfoo:
+            foo = "Objfoo"
+
+        class Objbar:
+            bar = "Objbar"
+
+        f = F()
+        assert "defaultvalue" == f.foo.data
+        assert (
+            """<input id="bar" name="bar" type="text" value="defaultvalue">"""
+            == f.foo()
+        )
+
+        f = F(bar="formvalue")
+        assert "formvalue" == f.foo.data
+        assert (
+            """<input id="bar" name="bar" type="text" value="formvalue">""" == f.foo()
+        )
+
+        f = F(foo="formvalue")
+        assert "defaultvalue" == f.foo.data
+        assert (
+            """<input id="bar" name="bar" type="text" value="defaultvalue">"""
+            == f.foo()
+        )
+
+        f = F(None, Objbar())
+        assert "defaultvalue" == f.foo.data
+        assert (
+            """<input id="bar" name="bar" type="text" value="defaultvalue">"""
+            == f.foo()
+        )
+
 
 class PrePostTestField(StringField):
     def pre_validate(self, form):
@@ -976,6 +1013,24 @@ def make_inner():
         with pytest.raises(TypeError):
             form.populate_obj(obj2)
 
+    def test_enclosed_subform_custom_name(self):
+        class Inside(Form):
+            foo = StringField(name="bar", default="defaultvalue")
+
+        class Outside(Form):
+            subforms = FieldList(FormField(Inside), min_entries=1)
+
+        o = Outside()
+        assert "defaultvalue" == o.subforms[0].foo.data
+
+        pdata = DummyPostData({"subforms-0-bar": "formvalue"})
+        o = Outside(pdata)
+        assert "formvalue" == o.subforms[0].foo.data
+
+        pdata = DummyPostData({"subforms-0-foo": "formvalue"})
+        o = Outside(pdata)
+        assert "defaultvalue" == o.subforms[0].foo.data
+
     def test_entry_management(self):
         F = make_form(a=FieldList(self.t))
         a = F(a=["hello", "bye"]).a