== Why is this an issue?

Mockito provides _argument matchers_ for flexibly stubbing or verifying method calls.


``++Mockito.verify()++``, ``++Mockito.when()++``, ``++Stubber.when()++`` and ``++BDDMockito.given()++`` each have overloads with and without argument matchers.


However, the default matching behavior (i.e. without argument matchers) uses ``++equals()++``. If only the matcher ``++org.mockito.ArgumentMatchers.eq()++`` is used, the call is equivalent to the call without matchers, i.e. the ``++eq()++`` is not necessary and can be omitted. The resulting code is shorter and easier to read.


=== Noncompliant code example

[source,java]
----
@Test
public void myTest() {
  given(foo.bar(eq(v1), eq(v2), eq(v3))).willReturn(null);   // Noncompliant
  when(foo.baz(eq(v4), eq(v5))).thenReturn("foo");   // Noncompliant
  doThrow(new RuntimeException()).when(foo).quux(eq(42));    // Noncompliant
  verify(foo).bar(eq(v1), eq(v2), eq(v3));   // Noncompliant
}
----


=== Compliant solution

[source,java]
----
@Test
public void myTest() {
  given(foo.bar(v1, v2, v3)).willReturn(null);
  when(foo.baz(v4, v5)).thenReturn("foo");
  doThrow(new RuntimeException()).when(foo).quux(42);
  verify(foo).bar(v1, v2, v3);
}
----


== Resources

* https://javadoc.io/doc/org.mockito/mockito-core/latest/org/mockito/Mockito.html#argument_matchers[Mockito documentation] - argument matchers
* S6073 - Mockito argument matchers should be used on all parameters



ifdef::env-github,rspecator-view[]

'''
== Implementation Specification
(visible only on this page)

=== Message

Remove this/these useless "eq" invocation and directly use the value


=== Highlighting

primary: first "eq()"

secondary: other subsequent "eq()" in the rest of the method invocation


'''
== Comments And Links
(visible only on this page)

=== is related to: S6073

=== on 6 Nov 2020, 17:07:19 Michael Gumowski wrote:
Rule idea contributed by Björn Duderstadt, in the community: \https://community.sonarsource.com/t/java-call-to-mockito-method-verify-when-or-given-can-be-simplified/33974

endif::env-github,rspecator-view[]