added the havecap matcher
diff --git a/matchers.go b/matchers.go
index b6110c4..afb7720 100644
--- a/matchers.go
+++ b/matchers.go
@@ -217,6 +217,13 @@
}
}
+//HaveCap succeeds if actual has the passed-in capacity. Actual must be of type array, chan, or slice.
+func HaveCap(count int) types.GomegaMatcher {
+ return &matchers.HaveCapMatcher{
+ Count: count,
+ }
+}
+
//BeZero succeeds if actual is the zero value for its type or if actual is nil.
func BeZero() types.GomegaMatcher {
return &matchers.BeZeroMatcher{}
diff --git a/matchers/have_cap_matcher.go b/matchers/have_cap_matcher.go
new file mode 100644
index 0000000..7ace93d
--- /dev/null
+++ b/matchers/have_cap_matcher.go
@@ -0,0 +1,28 @@
+package matchers
+
+import (
+ "fmt"
+
+ "github.com/onsi/gomega/format"
+)
+
+type HaveCapMatcher struct {
+ Count int
+}
+
+func (matcher *HaveCapMatcher) Match(actual interface{}) (success bool, err error) {
+ length, ok := capOf(actual)
+ if !ok {
+ return false, fmt.Errorf("HaveCap matcher expects a array/channel/slice. Got:\n%s", format.Object(actual, 1))
+ }
+
+ return length == matcher.Count, nil
+}
+
+func (matcher *HaveCapMatcher) FailureMessage(actual interface{}) (message string) {
+ return fmt.Sprintf("Expected\n%s\nto have capacity %d", format.Object(actual, 1), matcher.Count)
+}
+
+func (matcher *HaveCapMatcher) NegatedFailureMessage(actual interface{}) (message string) {
+ return fmt.Sprintf("Expected\n%s\nnot to have capacity %d", format.Object(actual, 1), matcher.Count)
+}
diff --git a/matchers/have_cap_matcher_test.go b/matchers/have_cap_matcher_test.go
new file mode 100644
index 0000000..a92a177
--- /dev/null
+++ b/matchers/have_cap_matcher_test.go
@@ -0,0 +1,50 @@
+package matchers_test
+
+import (
+ . "github.com/onsi/ginkgo"
+ . "github.com/onsi/gomega"
+ . "github.com/onsi/gomega/matchers"
+)
+
+var _ = Describe("HaveCap", func() {
+ Context("when passed a supported type", func() {
+ It("should do the right thing", func() {
+ Ω([0]int{}).Should(HaveCap(0))
+ Ω([2]int{1}).Should(HaveCap(2))
+
+ Ω([]int{}).Should(HaveCap(0))
+ Ω([]int{1, 2, 3, 4, 5}[:2]).Should(HaveCap(5))
+ Ω(make([]int, 0, 5)).Should(HaveCap(5))
+
+ c := make(chan bool, 3)
+ Ω(c).Should(HaveCap(3))
+ c <- true
+ c <- true
+ Ω(c).Should(HaveCap(3))
+
+ Ω(make(chan bool)).Should(HaveCap(0))
+ })
+ })
+
+ Context("when passed a correctly typed nil", func() {
+ It("should operate succesfully on the passed in value", func() {
+ var nilSlice []int
+ Ω(nilSlice).Should(HaveCap(0))
+
+ var nilChan chan int
+ Ω(nilChan).Should(HaveCap(0))
+ })
+ })
+
+ Context("when passed an unsupported type", func() {
+ It("should error", func() {
+ success, err := (&HaveCapMatcher{Count: 0}).Match(0)
+ Ω(success).Should(BeFalse())
+ Ω(err).Should(HaveOccurred())
+
+ success, err = (&HaveCapMatcher{Count: 0}).Match(nil)
+ Ω(success).Should(BeFalse())
+ Ω(err).Should(HaveOccurred())
+ })
+ })
+})
diff --git a/matchers/type_support.go b/matchers/type_support.go
index ef9b448..04020f0 100644
--- a/matchers/type_support.go
+++ b/matchers/type_support.go
@@ -150,6 +150,17 @@
return 0, false
}
}
+func capOf(a interface{}) (int, bool) {
+ if a == nil {
+ return 0, false
+ }
+ switch reflect.TypeOf(a).Kind() {
+ case reflect.Array, reflect.Chan, reflect.Slice:
+ return reflect.ValueOf(a).Cap(), true
+ default:
+ return 0, false
+ }
+}
func isNil(a interface{}) bool {
if a == nil {
