feat: formatter for HTTP responses (#461)

Previously when the HaveHTTPStatus() matcher failed, the whole HTTP
response object was printed out, and any message was rendered in
bytes rather than as a string.

This introduces a formatter for HTTP responses, so that the key data is
presented in a helpful format.

matchers/have_http_status_matcher.go

@@ -2,8 +2,11 @@ package matchers
 
 import (
 	"fmt"
+	"io/ioutil"
 	"net/http"
 	"net/http/httptest"
+	"reflect"
+	"strings"
 
 	"github.com/onsi/gomega/format"
 )
@@ -34,9 +37,40 @@ func (matcher *HaveHTTPStatusMatcher) Match(actual interface{}) (success bool, e
 }
 
 func (matcher *HaveHTTPStatusMatcher) FailureMessage(actual interface{}) (message string) {
-	return format.Message(actual, "to have HTTP status", matcher.Expected)
+	return fmt.Sprintf("Expected\n%s\n%s\n%s", formatHttpResponse(actual), "to have HTTP status", format.Object(matcher.Expected, 1))
 }
 
 func (matcher *HaveHTTPStatusMatcher) NegatedFailureMessage(actual interface{}) (message string) {
-	return format.Message(actual, "not to have HTTP status", matcher.Expected)
+	return fmt.Sprintf("Expected\n%s\n%s\n%s", formatHttpResponse(actual), "not to have HTTP status", format.Object(matcher.Expected, 1))
+}
+
+func formatHttpResponse(input interface{}) string {
+	var resp *http.Response
+	switch r := input.(type) {
+	case *http.Response:
+		resp = r
+	case *httptest.ResponseRecorder:
+		resp = r.Result()
+	default:
+		return "cannot format invalid HTTP response"
+	}
+
+	body := "<nil>"
+	if resp.Body != nil {
+		defer resp.Body.Close()
+		data, err := ioutil.ReadAll(resp.Body)
+		if err != nil {
+			data = []byte("<error reading body>")
+		}
+		body = format.Object(string(data), 0)
+	}
+
+	var s strings.Builder
+	s.WriteString(fmt.Sprintf("%s<%s>: {\n", format.Indent, reflect.TypeOf(input)))
+	s.WriteString(fmt.Sprintf("%s%sStatus:     %s\n", format.Indent, format.Indent, format.Object(resp.Status, 0)))
+	s.WriteString(fmt.Sprintf("%s%sStatusCode: %s\n", format.Indent, format.Indent, format.Object(resp.StatusCode, 0)))
+	s.WriteString(fmt.Sprintf("%s%sBody:       %s\n", format.Indent, format.Indent, body))
+	s.WriteString(fmt.Sprintf("%s}", format.Indent))
+
+	return s.String()
 }

matchers/have_http_status_matcher_test.go

@@ -1,8 +1,10 @@
 package matchers_test
 
 import (
+	"io/ioutil"
 	"net/http"
 	"net/http/httptest"
+	"strings"
 
 	. "github.com/onsi/ginkgo"
 	. "github.com/onsi/gomega"
@@ -17,13 +19,15 @@ var _ = Describe("HaveHTTPStatus", func() {
 				Expect(resp).NotTo(HaveHTTPStatus(http.StatusNotFound))
 			})
 		})
+
 		When("EXPECTED is string", func() {
 			It("matches the Status", func() {
 				resp := &http.Response{Status: "200 OK"}
 				Expect(resp).To(HaveHTTPStatus("200 OK"))
 				Expect(resp).NotTo(HaveHTTPStatus("404 Not Found"))
 			})
 		})
+
 		When("EXPECTED is anything else", func() {
 			It("does not match", func() {
 				failures := InterceptGomegaFailures(func() {
@@ -43,13 +47,15 @@ var _ = Describe("HaveHTTPStatus", func() {
 				Expect(resp).NotTo(HaveHTTPStatus(http.StatusNotFound))
 			})
 		})
+
 		When("EXPECTED is string", func() {
 			It("matches the Status", func() {
 				resp := &httptest.ResponseRecorder{Code: http.StatusOK}
 				Expect(resp).To(HaveHTTPStatus("200 OK"))
 				Expect(resp).NotTo(HaveHTTPStatus("404 Not Found"))
 			})
 		})
+
 		When("EXPECTED is anything else", func() {
 			It("does not match", func() {
 				failures := InterceptGomegaFailures(func() {
@@ -73,19 +79,44 @@ var _ = Describe("HaveHTTPStatus", func() {
 	Describe("FailureMessage", func() {
 		It("returns message", func() {
 			failures := InterceptGomegaFailures(func() {
-				resp := &http.Response{StatusCode: http.StatusBadGateway}
+				resp := &http.Response{
+					StatusCode: http.StatusBadGateway,
+					Status:     "502 Bad Gateway",
+					Body:       ioutil.NopCloser(strings.NewReader("did not like it")),
+				}
 				Expect(resp).To(HaveHTTPStatus(http.StatusOK))
 			})
-			Expect(failures).To(ConsistOf(MatchRegexp("Expected(.|\n)*StatusCode: 502(.|\n)*to have HTTP status\n    <int>: 200")))
+			Expect(failures).To(HaveLen(1))
+			Expect(failures[0]).To(Equal(`Expected
+    <*http.Response>: {
+        Status:     <string>: "502 Bad Gateway"
+        StatusCode: <int>: 502
+        Body:       <string>: "did not like it"
+    }
+to have HTTP status
+    <int>: 200`), failures[0])
 		})
 	})
+
 	Describe("NegatedFailureMessage", func() {
 		It("returns message", func() {
 			failures := InterceptGomegaFailures(func() {
-				resp := &http.Response{StatusCode: http.StatusOK}
+				resp := &http.Response{
+					StatusCode: http.StatusOK,
+					Status:     "200 OK",
+					Body:       ioutil.NopCloser(strings.NewReader("got it!")),
+				}
 				Expect(resp).NotTo(HaveHTTPStatus(http.StatusOK))
 			})
-			Expect(failures).To(ConsistOf(MatchRegexp("Expected(.|\n)*StatusCode: 200(.|\n)*not to have HTTP status\n    <int>: 200")))
+			Expect(failures).To(HaveLen(1))
+			Expect(failures[0]).To(Equal(`Expected
+    <*http.Response>: {
+        Status:     <string>: "200 OK"
+        StatusCode: <int>: 200
+        Body:       <string>: "got it!"
+    }
+not to have HTTP status
+    <int>: 200`), failures[0])
 		})
 	})
 })