Make iterating over keys possible (#63)

* Make iterating over keys possible

* add test for cmap
- test Keys() and Values() respectively

* one cmap per test-case

common/cmap.go

@@ -51,6 +51,17 @@ func (cm *CMap) Clear() {
 	cm.m = make(map[string]interface{})
 }
 
+func (cm *CMap) Keys() []string {
+	cm.l.Lock()
+	defer cm.l.Unlock()
+
+	keys := []string{}
+	for k := range cm.m {
+		keys = append(keys, k)
+	}
+	return keys
+}
+
 func (cm *CMap) Values() []interface{} {
 	cm.l.Lock()
 	defer cm.l.Unlock()

common/cmap_test.go

@@ -0,0 +1,63 @@
+package common
+
+import (
+	"fmt"
+	"strings"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestIterateKeysWithValues(t *testing.T) {
+	cmap := NewCMap()
+
+	for i := 1; i <= 10; i++ {
+		cmap.Set(fmt.Sprintf("key%d", i), fmt.Sprintf("value%d", i))
+	}
+
+	// Testing size
+	assert.Equal(t, cmap.Size(), 10, "overall size should be 10")
+	assert.Equal(t, len(cmap.Keys()), 10, "should be 10 keys")
+	assert.Equal(t, len(cmap.Values()), 10, "should be 10 values")
+
+	// Iterating Keys, checking for matching Value
+	for _, key := range cmap.Keys() {
+		val := strings.Replace(key, "key", "value", -1)
+		assert.Equal(t, cmap.Get(key), val)
+	}
+
+	// Test if all keys are within []Keys()
+	keys := cmap.Keys()
+	for i := 1; i <= 10; i++ {
+		assert.True(t, contains(keys, fmt.Sprintf("key%d", i)), "cmap.Keys() should contain key")
+	}
+
+	// Delete 1 Key
+	cmap.Delete("key1")
+
+	assert.NotEqual(t, len(keys), len(cmap.Keys()), "[]keys and []Keys() should not be equal, they are copies, one item was removed")
+
+}
+
+func TestContains(t *testing.T) {
+	cmap := NewCMap()
+
+	cmap.Set("key1", "value1")
+
+	// Test for known values
+	assert.True(t, cmap.Has("key1"), "should contain key1")
+	assert.Equal(t, cmap.Get("key1"), "value1", "key1.value() should be value1")
+
+	// Test for unknown values
+	assert.False(t, cmap.Has("key2"), "should not contain key2")
+	assert.Nil(t, cmap.Get("key2"), "does not contain key2")
+}
+
+func contains(array []string, value string) (bool) {
+	for _, val := range array {
+		if val == value {
+			return true
+		}
+	}
+	return false
+}