implement a simple path param binder

Former-commit-id: 2edc7f115332b7afe42d6b0b1b7b6edd4a44a121

mvc2/path_param_test.go

@@ -0,0 +1,66 @@
+package mvc2
+
+import (
+	"testing"
+
+	"github.com/kataras/iris/context"
+)
+
+func TestPathParamsBinder(t *testing.T) {
+	m := New()
+	m.In(PathParamsBinder)
+
+	got := ""
+
+	h := m.Handler(func(params PathParams) {
+		got = params.Get("firstname") + params.Get("lastname")
+	})
+
+	ctx := context.NewContext(nil)
+	ctx.Params().Set("firstname", "Gerasimos")
+	ctx.Params().Set("lastname", "Maropoulos")
+	h(ctx)
+	expected := "GerasimosMaropoulos"
+	if got != expected {
+		t.Fatalf("expected the params 'firstname' + 'lastname' to be '%s' but got '%s'", expected, got)
+	}
+}
+func TestPathParamBinder(t *testing.T) {
+	m := New()
+	m.In(PathParamBinder("username"))
+
+	got := ""
+	executed := false
+	h := m.Handler(func(username PathParam) {
+		// this should not be fired at all if "username" param wasn't found at all.
+		// although router is responsible for that but the `ParamBinder` makes that check as well because
+		// the end-developer may put a param as input argument on her/his function but
+		// on its route's path didn't describe the path parameter,
+		// the handler fires a warning and stops the execution for the invalid handler to protect the user.
+		executed = true
+		got = username.String()
+	})
+
+	expectedUsername := "kataras"
+	ctx := context.NewContext(nil)
+	ctx.Params().Set("username", expectedUsername)
+	h(ctx)
+
+	if got != expectedUsername {
+		t.Fatalf("expected the param 'username' to be '%s' but got '%s'", expectedUsername, got)
+	}
+
+	// test the non executed if param not found.
+	executed = false
+	got = ""
+
+	ctx2 := context.NewContext(nil)
+	h(ctx2)
+
+	if got != "" {
+		t.Fatalf("expected the param 'username' to be entirely empty but got '%s'", got)
+	}
+	if executed {
+		t.Fatalf("expected the handler to not be executed")
+	}
+}