},
			ok:  false,
			out: "+pkg syscall, type RawSockaddrInet6 struct\n",
		},
	}
	for _, tt := range tests {
		buf := new(strings.Builder)
		gotOK := compareAPI(buf, tt.features, tt.required, tt.exception)
		if gotOK != tt.ok {
			t.Errorf("%s: ok = %v; want %v", tt.name, gotOK, tt.ok)
		}
		if got := buf.String(); got != tt.out {

	}
	exception := fileFeatures(filepath.Join(testenv.GOROOT(t), "api/except.txt"), false)

	if exitCode == 1 {
		t.Errorf("API database problems found")
	}
	if !compareAPI(bw, features, required, exception) {
		t.Errorf("API differences found")
	}
}

// export emits the exported package features.
func (w *Walker) export(pkg *apiPackage) {
	if verbose {
		log.Println(pkg)