code review 5708055: net/http: fix ProxyFromEnvironment bug, docs, add tests

src/pkg/net/http/transport_test.go

Index: src/pkg/net/http/transport_test.go
===================================================================
--- a/src/pkg/net/http/transport_test.go
+++ b/src/pkg/net/http/transport_test.go
@@ -16,6 +16,7 @@
 	. "net/http"
 	"net/http/httptest"
 	"net/url"
+	"os"
 	"runtime"
 	"strconv"
 	"strings"
@@ -727,6 +728,36 @@
 	}
 }
 
+var proxyFromEnvTests = []struct {
+	env     string
+	wanturl string
+	wanterr error
+}{
+	{"127.0.0.1:8080", "http://127.0.0.1:8080", nil},
+	{"http://127.0.0.1:8080", "http://127.0.0.1:8080", nil},
+	{"https://127.0.0.1:8080", "https://127.0.0.1:8080", nil},
+	{"", "<nil>", nil},
+}
+
+func TestProxyFromEnvironment(t *testing.T) {
+	os.Setenv("HTTP_PROXY", "")
+	os.Setenv("http_proxy", "")
+	os.Setenv("NO_PROXY", "")
+	os.Setenv("no_proxy", "")
+	for i, tt := range proxyFromEnvTests {
+		os.Setenv("HTTP_PROXY", tt.env)
+		req, _ := NewRequest("GET", "http://example.com", nil)
+		url, err := ProxyFromEnvironment(req)
+		if g, e := fmt.Sprintf("%v", err), fmt.Sprintf("%v", tt.wanterr); g != e {
+			t.Errorf("%d. got error = %q, want %q", i, g, e)
+			continue
+		}
+		if got := fmt.Sprintf("%s", url); got != tt.wanturl {
+			t.Errorf("%d. got URL = %q, want %q", i, url, tt.wanturl)
+		}
+	}
+}
+
 // rgz is a gzip quine that uncompresses to itself.
 var rgz = []byte{
 	0x1f, 0x8b, 0x08, 0x08, 0x00, 0x00, 0x00, 0x00,