From 92d56725f73ca25135dae914daaf17dabe074eeb Mon Sep 17 00:00:00 2001
From: Owen <ojracc@gmail.com>
Date: Wed, 24 Apr 2019 11:36:47 -0400
Subject: [PATCH] Unwrap error in Amazon validator

In amazon/validator.go, an error was being wrapped by fmt.Errorf("%v",
err). That discards any type information about the returned error;
returning err lets the callers inspect the exact error returned by the
HTTP client.

The test had to change to do similar inspection.
---
 amazon/validator.go      |  2 +-
 amazon/validator_test.go | 13 ++++++++++---
 2 files changed, 11 insertions(+), 4 deletions(-)

diff --git a/amazon/validator.go b/amazon/validator.go
index ea32c8f..0a3eb68 100644
--- a/amazon/validator.go
+++ b/amazon/validator.go
@@ -95,7 +95,7 @@ func (c *Client) Verify(ctx context.Context, userID string, receiptID string) (I
 
 	resp, err := c.httpCli.Do(req)
 	if err != nil {
-		return result, fmt.Errorf("%v", err)
+		return result, err
 	}
 	defer resp.Body.Close()
 
diff --git a/amazon/validator_test.go b/amazon/validator_test.go
index 4bc9629..1cc80cb 100644
--- a/amazon/validator_test.go
+++ b/amazon/validator_test.go
@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"net/http"
 	"net/http/httptest"
+	"net/url"
 	"os"
 	"reflect"
 	"testing"
@@ -143,11 +144,17 @@ func TestVerifyTimeout(t *testing.T) {
 	server, client := testTools(100, "timeout response")
 	defer server.Close()
 
-	expected := errors.New("")
 	ctx := context.Background()
 	_, actual := client.Verify(ctx, "timeout", "timeout")
-	if !reflect.DeepEqual(reflect.TypeOf(actual), reflect.TypeOf(expected)) {
-		t.Errorf("got %v\nwant %v", actual, expected)
+
+	// Actual should be a "request canceled" *url.Error
+	urlErr, ok := actual.(*url.Error)
+	if !ok {
+		t.Errorf("Expected *url.Error, got %T", actual)
+	}
+
+	if !urlErr.Timeout() {
+		t.Errorf("got %v\nwant timeout", actual)
 	}
 }