fs/rc: add Copy method to rc.Params

fs/rc/params.go

@@ -79,6 +79,15 @@ func Reshape(out interface{}, in interface{}) error {
 	return nil
 }
 
+// Copy shallow copies the Params
+func (p Params) Copy() (out Params) {
+	out = make(Params, len(p))
+	for k, v := range p {
+		out[k] = v
+	}
+	return out
+}
+
 // Get gets a parameter from the input
 //
 // If the parameter isn't found then error will be of type

fs/rc/params_test.go

@@ -63,6 +63,19 @@ func TestReshape(t *testing.T) {
 
 }
 
+func TestParamsCopy(t *testing.T) {
+	in := Params{
+		"ok":  1,
+		"x":   "seventeen",
+		"nil": nil,
+	}
+	out := in.Copy()
+	assert.Equal(t, in, out)
+	if &in == &out {
+		t.Error("didn't copy")
+	}
+}
+
 func TestParamsGet(t *testing.T) {
 	in := Params{
 		"ok": 1,