While Adding New Entity, Identity value is not generated - breeze

I am running into problem, where i extend the Entity to expose hasValidationError. Without that it works fine. Also i found that if I supply the ID before adding the entity it works fine as well. Why is the ID field not auto generating once the entity is extended on the client.
I am now using little different version of the code(i find it more intuitive to extend the entity this way), but it still errors out in the same way.
var Country = function () {
console.log("Country initialized");
var self = this;
self.Country_ID = ko.observable("");
self.Country_Code = ko.observable("");
self.Country_Name = ko.observable().extend({
validation: {
validator: function (val, someOtherVal) {
return false;//val === someOtherVal;
},
message: 'Invalid Value!',
params: 5
}
});
var prop = ko.observable(false);
var onChange = function () {
var hasError = self.entityAspect.getValidationErrors().length > 0;
if (prop() === hasError) {
// collection changed even though entity net error state is unchanged
prop.valueHasMutated(); // force notification
} else {
prop(hasError); // change the value and notify
}
};
// observable property is wired up; now add it to the entity
self.hasValidationErrors = prop;
//dummy property to wireup event
//should not be used for any other purpose
self.hasError = ko.computed(
{
read: function () {
self.entityAspect // ... and when errors collection changes
.validationErrorsChanged.subscribe(onChange);
},
// required because entityAspect property will not be available till Query
// return some data
deferEvaluation: true
});
self.fullName = ko.computed(
function () {
return self.Country_Code() + " --- " + self.Country_Name();
});
};
store.registerEntityTypeCtor("Country", Country);
and then in the button click i am using the following code to create new entity.
var countryType = manager.metadataStore.getEntityType("Country");
var newCountry = countryType.createEntity();
//newCountry.Country_ID(200); //if i add this line no errors occurs
newCountry.Country_Code("India");
self.list.push(newCountry);
manager.addEntity(newCountry); // validation error occurs right after this line
self.selectedItem(newCountry);
self.list.valueHasMutated();

Entities will only get their own autogenerated key if the metadata for their type specifies that this is supported. i.e.
if (myEntityType.autoGeneratedKeyType === AutoGeneratedKeyType.Identity)
This setting means that the key property of the entity is automatically generated by the server, typically for an 'Identity' column on your database.
or
if (myEntityType.autoGeneratedKeyType === AutoGeneratedKeyType.KeyGenerated)
This setting means that you have a server side KeyGenerator that can generate the key for you.
By default, however, myEntityType.autoGeneratedKeyType will equal AutoGeneratedKeyType.None.
In either of the other two cases, breeze will generate a temporary key on the client and then fix it up after a save completes with a 'real' key generated on the server.
If you do not need this capability, then simply create your own ctor for your type that generates a unique key and set it there. see MetadataStore.registerEntityTypeCtor for more details on how to register your ctor.
We are planning on improving our documentation in this area but haven't yet gotten there. I hope this helps.

Perhaps there is nothing wrong at all. How do you know that the id generation is failing? Is it a negative number after adding the newCountry to the manager? It should be.
What is the validation error that you are getting? Does it relate to Country_ID? Perhaps you have a validation constraint (e.g., minimum value) on Country_ID?
The addhasValidationErrorsProperty entity initializer works as intended. I just added a teaching test to the DocCode sample (see "Can create employee after registering addhasValidationErrorsProperty initializer" in entityExtensionTests.js). We haven't deployed it as I write this but you can get it from GitHub.
It follows your example as best I can with the Northwind Employee entity which has an identity id (Employee_ID). The test shows adding the initializer that I wrote in the previous post (not as you may have rewritten it). It shows that the new Employee's id is zero before adding to the manager and becomes -1 after adding to the manager. The -1 is the temporary id of the new employee; it receives a permanent value after save.
The default validationOptions of an EntityManager are set so to validate an entity when it is attached (or added) to the manager. You can change that behavior to suit your needs.
The new employee is in an invalid state when created; it lacks the required First and Last name values (the test displays these errors). Therefore the hasValidationErrors observable becomes true after adding the new employee to the manager and the hasValidationErrors observable raises a change notification that a Knockout UI would hear; these test shows these two points.

Related

Breeze 1-To-Many Unidirectional Navigation Property not Populated

Breeze Version: 1.5.3
I'm experiencing something similiar to some older questions on SO but it seems like this "bug" is reoccurring:
I have a 1-To-Many unidirectional navigation property which is not populated. I have checked the metadata and the response from the server. I've even debugged into breeze and the node (or rawEntity) seems to be perfect.
I've tried to track it down and came to the conclusion, that it happens, because no "inverse"-Property is found for my Navigation Property and the mergeRelatedEntities-Function returning without updating the target Entity:
function mergeRelatedEntities(mc, navigationProperty, targetEntity, rawEntity) {
var relatedEntities = mergeRelatedEntitiesCore(mc, rawEntity, navigationProperty);
if (relatedEntities == null) return;
var inverseProperty = navigationProperty.inverse;
if (!inverseProperty) return;
var originalRelatedEntities = targetEntity.getProperty(navigationProperty.name);
originalRelatedEntities.wasLoaded = true;
relatedEntities.forEach(function (relatedEntity) {
if (typeof relatedEntity === 'function') {
mc.deferredFns.push(function () {
relatedEntity = relatedEntity();
updateRelatedEntityInCollection(relatedEntity, originalRelatedEntities, targetEntity, inverseProperty);
});
} else {
updateRelatedEntityInCollection(relatedEntity, originalRelatedEntities, targetEntity, inverseProperty);
}
});
}
Older Posts:
Non scalar navigation properties are not populating with "nodb" conception
and
Breeze (1.4.5) unidirectional one-to-many: navigation collection not populated
Edited 11. May 2015
Okay I start to understand what Ward meant with the unmapped properties (by finding a similar question from 2 years ago: Handling calculated properties with breezejs and web api)
What I have so far:
function iUIConfigConstructorTool() {
this.ConfigToCurrentUSetting = null;
};
function iUIConfigConstructorAppl() {
this.ConfigToCurrentUSetting = null;
};
function iUIConfigConstructorWidget() {
this.ConfigToCurrentUSetting = null;
};
function iUIConfigInitializer(uiConfigObject) {
// initializing other properties
};
this.manager.metadataStore.registerEntityTypeCtor("Tool", iUIConfigConstructorTool, iUIConfigInitializer);
this.manager.metadataStore.registerEntityTypeCtor("Appl", iUIConfigConstructorAppl, iUIConfigInitializer);
this.manager.metadataStore.registerEntityTypeCtor("Widget", iUIConfigConstructorWidget, iUIConfigInitializer);
This does what I want. Is there a way, to do this over the metamodel from the server? Because I define my calculated properties on the server and the metamodel is delivered by the server, I don't want to change the client-side implementation if I add a new Navigation-Property. So I'd need something like a flag in the metamodel to tell breeze, that this property needs to be filled as it comes over the wire without ForeignKeys etc.
Maybe in other words: We are doing "sub queries" on the server side (e.g. find Customers with it's Orders but only up to a certain Date) for each queried object and deliver this to breeze (in a separate property than the real orders-property of the Customer). Our problem is: How do we unpack this sub-query because there is no direct connection in metadata but we need the connection for the logic.
Please update your question with:
how you obtained/created metadata
metadata for the two endpoints (just the nav props, pk prop, and fk props will do)
the exact query expression
Of course a repro in plunker would be most welcome.
update 7 May 2015
If I understand your comment correctly, the navigation property (properties) in question are to be maintained by you (w/ server-supplied info), not by Breeze.
That leads me to suggest that you maintain them as unmapped properties rather than mapped, navigation properties. Does that make sense?

BreezeJS editing data not working

I was able to follow the instruction on adding data, that part was easy and understandable. But when I tried to follow instructions for editing data, I'm completely lost.
I am following the todo sample, which works quite well, but when I tried to add to my own project using the same principle, nothing works.
in my controller, I have the following:
function listenForPropertyChanged() {
// Listen for property change of ANY entity so we can (optionally) save
var token = dataservice.addPropertyChangeHandler(propertyChanged);
// Arrange to remove the handler when the controller is destroyed
// which won't happen in this app but would in a multi-page app
$scope.$on("$destroy", function () {
dataservice.removePropertyChangeHandler(token);
});
function propertyChanged(changeArgs) {
// propertyChanged triggers save attempt UNLESS the property is the 'Id'
// because THEN the change is actually the post-save Id-fixup
// rather than user data entry so there is actually nothing to save.
if (changeArgs.args.propertyName !== 'Id') { save(); }
}
}
The problem is that any time I change a control on the view, the propertyChanged callback function never gets called.
Here's the code from the service:
function addPropertyChangeHandler(handler) {
// Actually adds any 'entityChanged' event handler
// call handler when an entity property of any entity changes
return manager.entityChanged.subscribe(function (changeArgs) {
var action = changeArgs.entityAction;
if (action === breeze.EntityAction.PropertyChange) {
handler(changeArgs);
}
});
}
If I put a break point on the line:
var action = changeArgs.entityAction;
In my project, it never reaches there; in the todo sample, it does! It completely skips the whole thing and just loads the view afterwards. So none of my callback functions work at all; so really, nothing is subscribed.
Because of this, when I try to save changes, the manager.hasChanges() is always false and nothing happens in the database.
I've been trying for at least 3 days getting this to work, and I'm completely dumbfounded by how complicated this whole issue has been for me.
Note: I'm using JohnPapa's HotTowel template. I tried to follow the Todo editing functionality to a Tee.. and nothing is working the way I'd like it to.
Help would be appreciated.
The whole time I thought the problem was in the javascript client side end of things. Turned out that editing doesn't work when you created projected DTOs.
So in my server side, I created a query:
public IQueryable<PersonDTO> getPerson(){
return (from _person in ContextProvider.Context.Queries
select new PersonDTO
{
Id = _person.Id,
FirstName = _person.FirstName,
LastName = _person.LastName
}).AsQueryable();
}
Which just projected a DTO to send off to the client. This did work with my app in fetching data and populating things. So this is NOT wrong. Using this, I was able to add items and fetch items, but there's no information that allowed the entitymanager to know about the item. When I created an item, the entitymanager has a "createEntity" which allowed me to tell the entitymanager which item to use.. in my case:
manager.createEntity(person, initializeValues);
Maybe if there was a "manager.getEntity" maybe that would help?
Anyways, I changed the above query to get it straight from the source:
public IQueryable<Person> getPeople(){
return ContextProvider.Context.People;
}
Note ContextProvider is:
readonly EFContextProvider<PeopleEntities> ContextProvider =
new EFContextProvider<PeopleEntities>();
So the subscribe method in the javascript checks out the info that's retrieved straight from the contextual object.. interesting. Just wish I didn't spend 4 days on this.

propertyChanged for server calculated property not firing anymore in 1.4.12

i'm displaying a server calculated value to the enduser by using propertyChanged event.
i was using breeze 1.4.8 and i'm using the productivity stack (ms sql, web api, ef)
It was working fine.
Recently i've updated to 1.4.12 and i recognized that this event doesn't get fired anymore.
The property "A_ProvisionTotal" gets calculated serverside only.
<snip>
var token = vm.transaction.entityAspect.propertyChanged.subscribe(propertyChanged);
function propertyChanged(propertyChangedArgs) {
var propertyName = propertyChangedArgs.propertyName;
if (vm.transaction.tblEmployees.CalculationMethod == "A" && propertyName == "A_ProvisionTotal")
logSuccess('Provision neuberechnet' + '<br/>' + 'Aktuell: ' + $filter('number')(vm.transaction.Provision, 2), true);
</snip>
Let me know if this is a known regression and if you need more snippets.
A couple of thoughts for how you could accomplish your desired functionality.
The entity could remember the last calculated value in a private field. Then whenever the recalculation gets triggered, you can compare the new value to the last calculated value and if there is no change, ignore the new calculated value.
Alternatively, you could define the properties involved in your calculation as ES5 properties in the entity ctor function and then trigger the calculation in the setter of the relevant properties, when they get set with a new value. More information here: http://www.breezejs.com/documentation/extending-entities#es5-property. ES5 properties are convenient if you want to build behavior such as your calculation into setters.
Update 3
This is not a bug - see the response to this post that describes this as a documented and deliberate behavior.
Update 2 June 2014
I overlooked a key fact in your question ... one that only became clear to me after I looked at the code you included in your comments. Let me extract the key pieces for other readers:
Your test issues a query, then saves an unrelated change to the server (where the property-of-interest is updated server-side), then checks if that telltale property-of-interest raises propertyChanged when the save result is merged back into cache.
var query = EntityQuery.from("Orders").where('id', 'eq', 10248);
query.using(em).execute().then(querySucceeded).then(checkPropertyChanged).fin(start);
// querySucceed receives order 10248, updates an unrelated property (so you can save),
// wires up a propertyChanged listener and saves, returning the saveChanges promise
function checkPropertyChanged(saveResults) {
var saved = saveResults.entities[0];
// this passes because the server-side change to `Freight` was returned
ok(saved && saved.Freight() === 1200.00,
"freight got changed serverside");
// this fails because Breeze did not notify you that the `Freight` had changed
ok(notifications[0].propertyName === "Freight",
"notified serverside change of Freight Property");
}
Summarizing, you expected that a property change on the server would trigger a propertyChanged notification on the client when the entity data are re-retrieved from the server as a by-product of saveChanges.
Do I have that right?
Our documentation was not clear on whether the merge of query, save, and import entity results would raise propertyChanged.
I discussed internally and confirmed that these operations SHOULD raise propertyChanged. I also wrote another (somewhat simpler) test that reveals the bug you discovered: that merged save results may not raise propertyChanged.
We'll look into it and tell you when we've fixed it. Thanks for discovering it.
Original
We have regression tests that show that the Breeze EntityAspect.propertyChanged event is raised in v.1.4.12. For example, you can see it at work in the DocCode sample, "basicTodoTests.js"; scroll to: "Breeze propertyChanged raised when any property changes".
Can you confirm that it really is a Breeze failure? Perhaps the property you are changing is not actually an entity property? Sometimes you think you are changing an entity (e.g, your Transaction entity) but the thing whose property you changed isn't actually an entity. Then the problem is that the data you thought would be mapped to a Transaction was not ... and you can start looking for that quite different problem.
In any case, I suggest that you write a small test to confirm your suspicion ... most importantly for yourself ... and then for us. That will help us discover what is different about your scenario from our scenarios. We'll fix it if you can find it. Thanks.
Actually, I'm not sure that this is a bug. Property change events DO get fired during a save merge but the property name parameter is documented as being 'null' when fired as a result of a save.
http://www.breezejs.com/sites/all/apidocs/classes/EntityAspect.html#event_propertyChanged
From the API Docs for the 'propertyName' parameter returned by EntityAspect.propertyChanged:
The name of the property that changed. This value will be 'null' for operations that replace the entire entity. This includes queries, imports and saves that require a merge. The remaining parameters will not exist in this case either.
What may have happened between 1.4.8 and 1.4.13 is that we actually implemented our design spec more carefully and probably introduced your breaking behavior. ( which we should have documented as such but likely missed).
Update by Ward
I updated the DocCode test which first confirmed the behavior described in your question and then confirmed the documented behavior.
We do regret that we apparently neglected to implement the documented behavior earlier and that we didn't mention the breaking change in our release notes (since updated).
Here's that test:
asyncTest("propertyChanged raised when merged save result changes a property", 3, function () {
var em = newTodosEm();
var todo = em.createEntity('TodoItem', {Description: "Saved description" });
em.saveChanges().then(saveSucceeded).catch(handleFail).finally(start);
ok(todo.entityAspect.isBeingSaved, "new todo is in the act of being saved");
// This change should be overwritten with the server value when the save result is returned
// even though the entity is in an Added state and the MergeStrategy is PreserveChanges
// because save expects to merge server values into an entity it is saving
todo.Description("Changed on client before save returns");
var descriptionChanged = false;
todo.entityAspect.propertyChanged.subscribe(function (changeArgs) {
// Watch carefully! The subscription is called twice during merge
// 1) propertyName === "Id" (assigned with permanent ID)
// 2) propertyName === null (WAT?)
// and not called with propertyName === "Description" as you might have thought.
// Actually 'null' means "merged a lot of properties"
// Documented: http://www.breezejs.com/sites/all/apidocs/classes/EntityAspect.html#event_propertyChanged
// The reason for this: don't want to fire a ton of events on whole entity load
// especially when merging many entities at the same time.
if (changeArgs.propertyName === null || changeArgs.propertyName === 'Description') {
descriptionChanged = true;
}
});
function saveSucceeded(saveResult) {
var saved = saveResult.entities[0];
// passes
equal(saved && saved.Description(), "Saved description",
"the merge after save should have restored the saved description");
// fails
ok(descriptionChanged,
"should have raised propertyChanged after merge/update of 'Description' property");
}
});

Handling calculated properties with breezejs and web api

I'm experimenting with BreezeJS with Web API using the BreezeControllerAttribute. How should calculated properties on an entity be exposed? The only way I've found to do this reliably is to create an intermediate DTO that inherits from the entity or use a projection. Normally I would use a readonly property for this scenario, but those appear to be ignored.
When Breeze maps JSON property data to entities, it ignores properties that it does not recognize. That's why your server class's calculated property data are discarded even though you see them in the JSON on the wire.
Fortunately, you can teach Breeze to recognize the property by registering it as an unmapped property. I'll show you how. Let me give some background first.
Background
Your calculated property would be "known" to the Breeze client had it been a property calculated by the database. Database-backed properties (regular and calculated) are picked up in metadata as mapped properties.
But in your case (if I understand correctly) the property is defined in the logic of the server-side class, not in the database. Therefore it is not among the mapped properties in metadata. It is hidden from metadata. It is an unmapped instance property.
I assume you're not hiding it from the serializer. If you look at the network traffic for a query of the class, you can see your calculated property data arriving at the client. The problem is that Breeze is ignoring it when it "materializes" entities from these query results.
Solution with example
The solution is to register the calculated property in the MetadataStore.
I modified the entityExtensionTests.js of the DocCode sample to include this scenario; you can get that code from GitHub or wait for the next Breeze release.
Or just follow along with the code below, starting with this snippet from the Employee class in NorthwindModel.cs:
// Unmapped, server-side calculated property
[NotMapped] // Hidden from Entity Framework; still serialized to the client
public string FullName {
get { return LastName +
(String.IsNullOrWhiteSpace(FirstName)? "" : (", " + FirstName)); }
}
And here is the automated test in entityExtensionTests.js
test("unmapped property can be set by a calculated property of the server class", 2,
function () {
var store = cloneModuleMetadataStore(); // clones the Northwind MetadataStore
// custom Employee constructor
var employeeCtor = function () {
//'Fullname' is a server-side calculated property of the Employee class
// This unmapped property will be empty for new entities
// but will be set for existing entities during query materialization
this.FullName = "";
};
// register the custom constructor
store.registerEntityTypeCtor("Employee", employeeCtor);
var fullProp = store.getEntityType('Employee').getProperty('FullName');
ok(fullProp && fullProp.isUnmapped,
"'FullName' should be an unmapped property after registration");
var em = newEm(store); // helper creates a manager using this MetadataStore
var query = EntityQuery.from('Employees').using(em);
stop(); // going async
query.execute().then(success).fail(handleFail).fin(start);
function success(data) {
var first = data.results[0];
var full = first.FullName();
// passing test confirms that the FulllName property has a value
ok(full, "queried 'Employee' should have a fullname ('Last, First'); it is "+full);
}
});
What you need to do is in this small part of the test example:
var yourTypeCtor = function () {
this.calculatedProperty = ""; // "" or instance of whatever type is is supposed to be
};
// register your custom constructor
store.registerEntityTypeCtor("YourType", yourTypeCtor);

Unexpected Validate behavior with Moq

Moq has been driving me a bit crazy on my latest project. I recently upgraded to version 4.0.10827, and I'm noticing what seems to me to be a new behavior.
Basically, when I call my mocked function (MakeCall, in this example) in the code I am testing, I am passing in an object (TestClass). The code I am testing makes changes to the TestClass object before and after the call to MakeCall. Once the code has completed, I then call Moq's Verify function. My expectation is that Moq will have recorded the complete object that I passed into MakeCall, perhaps via a mechanism like deep cloning. This way, I will be able to verify that MakeCall was called with the exact object I am expecting it to be called with. Unfortunately, this is not what I'm seeing.
I attempt to illustrate this in the code below (hopefully, clarifying it a bit in the process).
I first create a new TestClass object. Its Var property is set to "one".
I then create the mocked object, mockedObject, which is my test subject.
I then call the MakeCall method of mockedObject (by the way, the Machine.Specifications framework used in the example allows the code in the When_Testing class to be read from top to bottom).
I then test the mocked object to ensure that it was indeed called with a TestClass with a Var value of "one". This succeeds, as I expected it to.
I then make a change to the original TestClass object by re-assigning the Var property to "two".
I then proceed to attempt to verify if Moq still thinks that MakeCall was called with a TestClass with a value of "one". This fails, although I am expecting it to be true.
Finally, I test to see if Moq thinks MakeCall was in fact called by a TestClass object with a value of "two". This succeeds, although I would initially have expected it to fail.
It seems pretty clear to me that Moq is only holding onto a reference to the original TestClass object, allowing me to change its value with impunity, adversely affecting the results of my testing.
A few notes on the test code. IMyMockedInterface is the interface I am mocking. TestClass is the class I am passing into the MakeCall method and therefore using to demonstrate the issue I am having. Finally, When_Testing is the actual test class that contains the test code. It is using the Machine.Specifications framework, which is why there are a few odd items ('Because of', 'It should...'). These are simply delegates that are called by the framework to execute the tests. They should be easily removed and the contained code placed into a standard function if that is desired. I left it in this format because it allows all Validate calls to complete (as compared to the 'Arrange, Act Assert' paradigm). Just to clarify, the below code is not the actual code I am having problems with. It is simply intended to illustrate the problem, as I have seen this same behavior in multiple places.
using Machine.Specifications;
// Moq has a conflict with MSpec as they both have an 'It' object.
using moq = Moq;
public interface IMyMockedInterface
{
int MakeCall(TestClass obj);
}
public class TestClass
{
public string Var { get; set; }
// Must override Equals so Moq treats two objects with the
// same value as equal (instead of comparing references).
public override bool Equals(object obj)
{
if ((obj != null) && (obj.GetType() != this.GetType()))
return false;
TestClass t = obj as TestClass;
if (t.Var != this.Var)
return false;
return true;
}
public override int GetHashCode()
{
int hash = 41;
int factor = 23;
hash = (hash ^ factor) * Var.GetHashCode();
return hash;
}
public override string ToString()
{
return MvcTemplateApp.Utilities.ClassEnhancementUtilities.ObjectToString(this);
}
}
[Subject(typeof(object))]
public class When_Testing
{
// TestClass is set up to contain a value of 'one'
protected static TestClass t = new TestClass() { Var = "one" };
protected static moq.Mock<IMyMockedInterface> mockedObject = new moq.Mock<IMyMockedInterface>();
Because of = () =>
{
mockedObject.Object.MakeCall(t);
};
// Test One
// Expected: Moq should verify that MakeCall was called with a TestClass with a value of 'one'.
// Actual: Moq does verify that MakeCall was called with a TestClass with a value of 'one'.
// Result: This is correct.
It should_verify_that_make_call_was_called_with_a_value_of_one = () =>
mockedObject.Verify(o => o.MakeCall(new TestClass() { Var = "one" }), moq.Times.Once());
// Update the original object to contain a new value.
It should_update_the_test_class_value_to_two = () =>
t.Var = "two";
// Test Two
// Expected: Moq should verify that MakeCall was called with a TestClass with a value of 'one'.
// Actual: The Verify call fails, claiming that MakeCall was never called with a TestClass instance with a value of 'one'.
// Result: This is incorrect.
It should_verify_that_make_call_was_called_with_a_class_containing_a_value_of_one = () =>
mockedObject.Verify(o => o.MakeCall(new TestClass() { Var = "one" }), moq.Times.Once());
// Test Three
// Expected: Moq should fail to verify that MakeCall was called with a TestClass with a value of 'two'.
// Actual: Moq actually does verify that MakeCall was called with a TestClass with a value of 'two'.
// Result: This is incorrect.
It should_fail_to_verify_that_make_call_was_called_with_a_class_containing_a_value_of_two = () =>
mockedObject.Verify(o => o.MakeCall(new TestClass() { Var = "two" }), moq.Times.Once());
}
I have a few questions regarding this:
Is this expected behavior?
Is this new behavior?
Is there a workaround that I am unaware of?
Am I using Verify incorrectly?
Is there a better way of using Moq to avoid this situation?
I thank you humbly for any assistance you can provide.
Edit:
Here is one of the actual tests and SUT code that I experienced this problem with. Hopefully it will act as clarification.
// This is the MVC Controller Action that I am testing. Note that it
// makes changes to the 'searchProjects' object before and after
// calling 'repository.SearchProjects'.
[HttpGet]
public ActionResult List(int? page, [Bind(Include = "Page, SearchType, SearchText, BeginDate, EndDate")]
SearchProjects searchProjects)
{
int itemCount;
searchProjects.ItemsPerPage = profile.ItemsPerPage;
searchProjects.Projects = repository.SearchProjects(searchProjects,
profile.UserKey, out itemCount);
searchProjects.TotalItems = itemCount;
return View(searchProjects);
}
// This is my test class for the controller's List action. The controller
// is instantiated in an Establish delegate in the 'with_project_controller'
// class, along with the SearchProjectsRequest, SearchProjectsRepositoryGet,
// and SearchProjectsResultGet objects which are defined below.
[Subject(typeof(ProjectController))]
public class When_the_project_list_method_is_called_via_a_get_request
: with_project_controller
{
protected static int itemCount;
protected static ViewResult result;
Because of = () =>
result = controller.List(s.Page, s.SearchProjectsRequest) as ViewResult;
// This test fails, as it is expecting the 'SearchProjects' object
// to contain:
// Page, SearchType, SearchText, BeginDate, EndDate and ItemsPerPage
It should_call_the_search_projects_repository_method = () =>
s.Repository.Verify(r => r.SearchProjects(s.SearchProjectsRepositoryGet,
s.UserKey, out itemCount), moq.Times.Once());
// This test succeeds, as it is expecting the 'SearchProjects' object
// to contain:
// Page, SearchType, SearchText, BeginDate, EndDate, ItemsPerPage,
// Projects and TotalItems
It should_call_the_search_projects_repository_method = () =>
s.Repository.Verify(r => r.SearchProjects(s.SearchProjectsResultGet,
s.UserKey, out itemCount), moq.Times.Once());
It should_return_the_correct_view_name = () =>
result.ViewName.ShouldBeEmpty();
It should_return_the_correct_view_model = () =>
result.Model.ShouldEqual(s.SearchProjectsResultGet);
}
/////////////////////////////////////////////////////
// Here are the values of the three test objects
/////////////////////////////////////////////////////
// This is the object that is returned by the client.
SearchProjects SearchProjectsRequest = new SearchProjects()
{
SearchType = SearchTypes.ProjectName,
SearchText = GetProjectRequest().Name,
Page = Page
};
// This is the object I am expecting the repository method to be called with.
SearchProjects SearchProjectsRepositoryGet = new SearchProjects()
{
SearchType = SearchTypes.ProjectName,
SearchText = GetProjectRequest().Name,
Page = Page,
ItemsPerPage = ItemsPerPage
};
// This is the complete object I expect to be returned to the view.
SearchProjects SearchProjectsResultGet = new SearchProjects()
{
SearchType = SearchTypes.ProjectName,
SearchText = GetProjectRequest().Name,
Page = Page,
ItemsPerPage = ItemsPerPage,
Projects = new List<Project>() { GetProjectRequest() },
TotalItems = TotalItems
};
Ultimately, your question is whether a mocking framework should take snapshots of the parameters you use when interacting with the mocks so that it can accurately record the state the system was in at the point of interaction rather than the state the parameters might be in at the point of verification.
I would say this is a reasonable expectation from a logical point of view. You are performing action X with value Y. If you ask the mock "Did I perform action X with value Y", you expect it to say "Yes" regardless of the current state of the system.
To summarize the problem you are running into:
You first invoke a method on a mock object with a reference type parameter.
Moq saves information about the invocation along with the reference type parameter passed in.
You then ask Moq if the method was called one time with an object equal to the reference you passed in.
Moq checks its history for a call to that method with a parameter that matches the supplied parameter and answers yes.
You then modify the object that you passed as the parameter to the method call on the mock.
The memory space of the reference Moq is holding in its history changes to the new value.
You then ask Moq if the method was called one time with an object that isn't equal to the reference its holding.
Mock checks its history for a call to that method with a parameter that matches the supplied parameter and reports no.
To attempt to answer your specific questions:
Is this expected behavior?
I would say no.
Is this new behavior?
I don't know, but it's doubtful the project would have at one time had behavior that facilitated this and was later modified to only allow the simple scenario of only verifying a single usage per mock.
Is there a workaround that I am unaware of?
I'll answer this two ways.
From a technical standpoint, a workaround would be to use a Test Spy rather than a Mock. By using a Test Spy, you can record the values passed and use your own strategy for remembering the state, such as doing a deep clone, serializing the object, or just storing the specific values you care about to be compared against later.
From a testing standpoint, I would recommend that you follow the principle "Use The Front Door First". I believe there is a time for state-based testing as well as interaction-based testing, but you should try to avoid coupling yourself to the implementation details unless the interaction is an important part of the scenario. In some cases, the scenario you are interested in will be primarily about interaction ("Transfer funds between accounts"), but in other cases all you really care about is getting the correct result ("Withdraw $10"). In the case of the specification for your controller, this seems to fall into the query category, not the command category. You don't really care how it gets the results you want as long as they are correct. Therefore, I would recommend using state-based testing in this case. If another specification concerns issuing a command against the system, there may still end up being a front door solution which you should consider using first, but it may be necessary or important to do interaction based testing. Just my thoughts though.
Am I using Verify incorrectly?
You are using the Verify() method correctly, it just doesn't support the scenario you are using it for.
Is there a better way of using Moq to avoid this situation?
I don't think Moq is currently implemented to handle this scenario.
Hope this helps,
Derek Greer
http://derekgreer.lostechies.com
http://aspiringcraftsman.com
#derekgreer
First, you can avoid the conflict between Moq and MSpec by declaring
using Machine.Specifications;
using Moq;
using It = Machine.Specifications.It;
Then you'll only need to prefix with Moq. when you want to use Moq's It, for example Moq.It.IsAny<>().
Onto your question.
Note: This is not the original answer but an edited one after the OP added some real example code to the question
I've been trying out your sample code and I think it's got more to do with MSpec than Moq. Apparently (and I didn't know this either), when you modify the state of your SUT (System Under Test) inside an It delegate the changes gets remembered. What is happening now is:
Because delegate is run
It delegates are run, one after the other. If one changes the state, the following It will never see the set up in the Because. Hence your failed test.
I've tried marking your spec with the SetupForEachSpecificationAttribute:
[Subject(typeof(object)), SetupForEachSpecification]
public class When_Testing
{
// Something, Something, something...
}
The attribute does as its name says: It will run your Establish and Because before every It. Adding the attribute made the spec behave as expected: 3 Successes, one fail (the verification that with Var = "two").
Would the SetupForEachSpecificationAttribute solve your problem or is resetting after every It not acceptable for your tests?
FYI: I'm using Moq v4.0.10827.0 and MSpec v0.4.9.0
Free tip #2: If you're testing ASP.NET MVC apps with Mspec you might want to take a look at James Broome's MSpec extensions for MVC

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