unit tests: identity deserializer

[aaadir]

Improve coverage of token/services/identity/deserializer/deserializer_test.go

[AkramBitar]

Did you check if we can use Counterfeiter to generate these mocks?

[AkramBitar]

Did you check if we can use Counterfeiter to generate these mocks?

Please check all of them

[aaadir]

Done.

• Counterfeiters for the following classes are now used instead of the previous manually defined mocks:

drivermock.Matcher
drivermock.Signer
drivermock.Verifier
drivermock.AuditInfoProvider
identitydrivermock.AuditInfo
identitydrivermock.AuditInfoDeserializer
identitydrivermock.TypedSignerDeserializer
identitydrivermock.TypedVerifierDeserializer

• Note that for the above I had to move the definition of the interface TypedVerifierDeserializer
  to be in token/services/identity/driver/deserialization.go next to the defnition of the interface TypedSignerDeserializer.
  It used to be in the file token/services/identity/deserializer/verifier.go which includes implementations of the TypedVerifierDeserializer interface.
  This caused dependency cycles for the new token/services/identity/deserializer/deserializer_test.go
  which was resolved when I moved the interface defintion to its proper place.

[adecaro]

Please, improve the tests to check:

• when an error is expected, to check also that the programmed errors are in there. For example, in

	t.Run("MatchError", func(t *testing.T) {
		expectedErr := errors.New("match failed")
		matcher := &drivermock.Matcher{}
		matcher.MatchReturns(expectedErr)

		typedMatcher := &TypedAuditInfoMatcher{matcher: matcher}
		typedID := createTypedIdentity(t, "test-type", []byte("raw-identity"))

		err := typedMatcher.Match(context.Background(), typedID)
		require.Error(t, err)
		assert.Contains(t, err.Error(), "failed to match identity")
	})

The test should check that expectedErr is in the error chain.

• If no error is expected, then the expected value should be checked. For example, in

	t.Run("GetAuditInfoMatcher_Success", func(t *testing.T) {
		mockVerifierDeserializer := &drivermock.VerifierDeserializer{}

		mockMatcher := &drivermock.Matcher{}
		mockMatcherDeserializer := &drivermock.MatcherDeserializer{}
		mockMatcherDeserializer.GetAuditInfoMatcherReturns(mockMatcher, nil)

		deserializer := NewTypedIdentityVerifierDeserializer(mockVerifierDeserializer, mockMatcherDeserializer)

		typedID := createTypedIdentity(t, "test-type", []byte("raw-identity"))
		matcher, err := deserializer.GetAuditInfoMatcher(context.Background(), typedID, []byte("audit-info"))

		require.NoError(t, err)
		assert.NotNil(t, matcher)
	})

The test should check that matcher is mockMatcher.

• counterfeiter allows the developer to check also how many times a function has been called. Please, add also the following checks.

[adecaro]

@aaadir , please, set the status of the PR and link it to its Issue. Thanks.

[aaadir]

pushed a new version addressing all the above review comments.
@adecaro - please approve (of you're ok with the requested changes).
thanks!

[adecaro]

LGTM