Value Matchers
Given any Ruby expression a, value matchers are expressed in the form:
| | expect(a).to matcher |
To negate a matcher, use either not_to or to_not rather than to:
| | expect(a).not_to matcher |
| | # or |
| | expect(a).to_not matcher |
Equality/Identity
| Matcher | Passes if… | Available aliases |
|---|---|---|
eq(x) | a == x |
an_object_eq_to(x) |
eql(x) | a.eql?(x) |
an_object_eql_to(x) |
equal(x) | a.equal?(x) |
be(x)an_object_equal_to(x) |
Truthiness and Nil
| Matcher | Passes if… | Available aliases |
|---|---|---|
be_truthy | a != nil && a != false | a_truthy_value |
be true | a == true | |
be_falsey | a == nil || a == false |
be_falsy a_falsey_value a_falsy_value |
be false | a == false | |
be_nil | a.nil? | a_nil_value |
Types
| Matcher | Passes if… | Available aliases |
|---|---|---|
be_an_instance_of(klass) | a.class == klass |
be_instance_of(klass) an_instance_of(klass) ... |
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