Merge pull request #3 from jbowes/github-tests

Add more github tests

impl/github.go

@@ -14,7 +14,8 @@ import (
 
 // GitHubReleaser is the default Releaser used in whatsnew.
 type GitHubReleaser struct {
-	URL string // a complete URL to the releases API.
+	URL    string       // a complete URL to the releases API.
+	Client *http.Client // if not set, http.DefaultClient is used.
 }
 
 // Get a list of releases.
@@ -35,9 +36,13 @@ func (g *GitHubReleaser) Get(ctx context.Context, etag string) ([]Release, strin
 
 	req = req.WithContext(ctx)
 
-	resp, err := http.DefaultClient.Do(req)
-	if err != nil {
+	c := g.Client
+	if c == nil {
+		c = http.DefaultClient
+	}
 
+	resp, err := c.Do(req)
+	if err != nil {
 		return nil, "", err
 	}
 	defer resp.Body.Close()

impl/github_test.go

@@ -0,0 +1,75 @@
+// Copyright (c) 2021 James Bowes. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package impl_test
+
+import (
+	"context"
+	"errors"
+	"net/http"
+	"testing"
+
+	"github.com/jbowes/whatsnew/impl"
+)
+
+func TestGihubReleaser(t *testing.T) {
+	ctx := context.Background()
+	ghr := &impl.GitHubReleaser{
+		URL: "http://github.com/repos/you/your-app/releases",
+		Client: &http.Client{
+			Transport: http.NewFileTransport(
+				http.Dir("../testdata/example"),
+			),
+		},
+	}
+	rels, etag, err := ghr.Get(ctx, `"some-etag"`)
+	if err != nil {
+		t.Errorf("got unexpected error: %s", err)
+	}
+
+	if len(rels) != 1 {
+		t.Errorf("wrong number of releases. expected: %d got: %d", 1, len(rels))
+	}
+	if rels[0].TagName != "0.30.0" {
+		t.Errorf("wrong tag name. expected: %s got: %s", "0.30.0", rels[0].TagName)
+	}
+
+	if etag != "" {
+		t.Errorf("wrong etag. expected: %s got: %s", "", etag)
+	}
+}
+
+func TestGihubReleaser_errorOn404(t *testing.T) {
+	ctx := context.Background()
+	ghr := &impl.GitHubReleaser{
+		URL: "http://github.com/repos/you/your-app/badurl",
+		Client: &http.Client{
+			Transport: http.NewFileTransport(
+				http.Dir("../testdata/example"),
+			),
+		},
+	}
+	_, _, err := ghr.Get(ctx, `"some-etag"`)
+	if err == nil {
+		t.Error("expected error but got none")
+	}
+}
+
+type errTripper struct{}
+
+func (errTripper) RoundTrip(*http.Request) (*http.Response, error) { return nil, errors.New("oops") }
+
+func TestGihubReleaser_errorOnRequest(t *testing.T) {
+	ctx := context.Background()
+	ghr := &impl.GitHubReleaser{
+		URL: "http://github.com/repos/you/your-app/badurl",
+		Client: &http.Client{
+			Transport: errTripper{},
+		},
+	}
+	_, _, err := ghr.Get(ctx, `"some-etag"`)
+	if err == nil {
+		t.Error("expected error but got none")
+	}
+}