diff --git a/cmd/godoc/godoc_test.go b/cmd/godoc/godoc_test.go
index a2552d9..82ed1e8 100644
--- a/cmd/godoc/godoc_test.go
+++ b/cmd/godoc/godoc_test.go
@@ -236,7 +236,12 @@
 	cmd.Stdout = os.Stderr
 	cmd.Stderr = os.Stderr
 	cmd.Args[0] = "godoc"
-	cmd.Env = godocEnv()
+
+	// Set GOPATH variable to non-existing path.
+	// We cannot just unset GOPATH variable because godoc would default it to ~/go.
+	// (We don't want the indexer looking at the local workspace during tests.)
+	cmd.Env = append(os.Environ(), "GOPATH=does_not_exist")
+
 	if err := cmd.Start(); err != nil {
 		t.Fatalf("failed to start godoc: %s", err)
 	}
@@ -390,14 +395,9 @@
 	defer cleanup()
 	addr := serverAddress(t)
 	cmd := exec.Command(bin, fmt.Sprintf("-http=%s", addr), "-analysis=type")
+	cmd.Env = os.Environ()
 	cmd.Env = append(cmd.Env, fmt.Sprintf("GOROOT=%s", filepath.Join(tmpdir, "goroot")))
 	cmd.Env = append(cmd.Env, fmt.Sprintf("GOPATH=%s", filepath.Join(tmpdir, "gopath")))
-	for _, e := range os.Environ() {
-		if strings.HasPrefix(e, "GOROOT=") || strings.HasPrefix(e, "GOPATH=") {
-			continue
-		}
-		cmd.Env = append(cmd.Env, e)
-	}
 	cmd.Stdout = os.Stderr
 	stderr, err := cmd.StderrPipe()
 	if err != nil {
@@ -475,15 +475,3 @@
 		}
 	}
 }
-
-// godocEnv returns the process environment without the GOPATH variable.
-// (We don't want the indexer looking at the local workspace during tests.)
-func godocEnv() (env []string) {
-	for _, v := range os.Environ() {
-		if strings.HasPrefix(v, "GOPATH=") {
-			continue
-		}
-		env = append(env, v)
-	}
-	return
-}