Add basic test of new hash staleness

myitcv · flimzy · commit a2b615d0090e · 2021-12-28T12:25:41.000+01:00
diff --git a/staleness_test.go b/staleness_test.go
@@ -0,0 +1,197 @@
+package main_test
+
+import (
+	"fmt"
+	"io/ioutil"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"runtime"
+	"strings"
+	"testing"
+	"time"
+)
+
+func TestBasicHashStaleness(t *testing.T) {
+	defer func() {
+		err := recover()
+		if err != nil {
+			t.Fatalf("got an expected error: %v", err.(error))
+		}
+	}()
+
+	h := newHashTester(t)
+
+	td := h.tempDir()
+	defer os.RemoveAll(td)
+	h.setEnv("GOPATH", td)
+	h.dir = h.mkdir(td, "src", "example.com", "rubbish")
+	h.mkdir(h.dir, "blah")
+	h.writeFile("main.go", `
+	package main
+	import "example.com/rubbish/blah"
+	func main() {
+		print(blah.Name)
+	}
+	`)
+	h.writeFile(filepath.Join("blah", "blah.go"), `
+	package blah
+	const Name = "blah"
+	`)
+	m := filepath.Join(td, "bin", "rubbish.js")
+	a := filepath.Join(td, "pkg", fmt.Sprintf("%v_js", runtime.GOOS), "example.com", "rubbish", "blah.a")
+
+	// variables to hold the current (c) and new (n) archive (a) and main (m)
+	// os.FileInfos
+	var ca, cm, na, nm os.FileInfo
+
+	// at this point neither main nor archive should exist
+	if h.statFile(m) != nil {
+		t.Fatalf("main %v existed when it shouldn't have", m)
+	}
+	if h.statFile(a) != nil {
+		t.Fatalf("archive %v existed when it shouldn't have", a)
+	}
+
+	h.run("gopherjs", "install", "example.com/rubbish")
+
+	// now both main and the archive should exist
+	ca = h.statFile(a)
+	if ca == nil {
+		t.Fatalf("archive %v should exist but doesn't", a)
+	}
+	cm = h.statFile(m)
+	if cm == nil {
+		t.Fatalf("main %v should exist but doesn't", a)
+	}
+
+	// re-running the install will cause main to be rewritten; not the package archive
+	h.run("gopherjs", "install", "example.com/rubbish")
+	nm = h.statFile(m)
+	if !nm.ModTime().After(cm.ModTime()) {
+		t.Fatalf("expected to see modified main file %v; got %v; prev %v", m, nm.ModTime(), cm.ModTime())
+	}
+	cm = nm
+	if na := h.statFile(a); !na.ModTime().Equal(ca.ModTime()) {
+		t.Fatalf("expected not to see modified archive file %v; got %v; want %v", a, na.ModTime(), ca.ModTime())
+	}
+
+	// touching the package file should have no effect on the archive
+	h.touch(filepath.Join("blah", "blah.go"))
+	h.run("gopherjs", "install", "example.com/rubbish/blah") // only install the package here
+	if na := h.statFile(a); !na.ModTime().Equal(ca.ModTime()) {
+		t.Fatalf("expected not to see modified archive file %v; got %v; want %v", a, na.ModTime(), ca.ModTime())
+	}
+
+	// now update package file - should cause modification time change
+	h.writeFile(filepath.Join("blah", "blah.go"), `
+	package blah
+	const Name = "GopherJS"
+	`)
+	h.run("gopherjs", "install", "example.com/rubbish")
+	na = h.statFile(a)
+	if !na.ModTime().After(ca.ModTime()) {
+		t.Fatalf("expected to see modified archive file %v; got %v; prev %v", a, na.ModTime(), ca.ModTime())
+	}
+	ca = na
+
+	// now change build tags - should cause modification time change
+	h.run("gopherjs", "install", "--tags", "asdf", "example.com/rubbish")
+	na = h.statFile(a)
+	if !na.ModTime().After(ca.ModTime()) {
+		t.Fatalf("expected to see modified archive file %v; got %v; prev %v", a, na.ModTime(), ca.ModTime())
+	}
+	ca = na
+}
+
+type hashTester struct {
+	t   *testing.T
+	dir string
+	env []string
+}
+
+func newHashTester(t *testing.T) *hashTester {
+	wd, err := os.Getwd()
+	if err != nil {
+		fatalf("run failed to get working directory: %v", err)
+	}
+	return &hashTester{
+		t:   t,
+		dir: wd,
+		env: os.Environ(),
+	}
+}
+
+func (h *hashTester) touch(path string) {
+	path = filepath.Join(h.dir, path)
+	now := time.Now().UTC()
+	if err := os.Chtimes(path, now, now); err != nil {
+		fatalf("failed to touch %v: %v", path, err)
+	}
+}
+
+func (h *hashTester) statFile(path string) os.FileInfo {
+	fi, err := os.Stat(path)
+	if err != nil {
+		if os.IsNotExist(err) {
+			return nil
+		}
+		fatalf("failed to stat %v: %v", path, err)
+	}
+
+	return fi
+}
+
+func (h *hashTester) setEnv(key, val string) {
+	newEnv := []string{fmt.Sprintf("%v=%v", key, val)}
+	for _, e := range h.env {
+		if !strings.HasPrefix(e, key+"=") {
+			newEnv = append(newEnv, e)
+		}
+	}
+	h.env = newEnv
+}
+
+func (h *hashTester) mkdir(dirs ...string) string {
+	d := filepath.Join(dirs...)
+	if err := os.MkdirAll(d, 0755); err != nil {
+		fatalf("failed to mkdir %v: %v\n", d, err)
+	}
+	return d
+}
+
+func (h *hashTester) writeFile(path, contents string) {
+	path = filepath.Join(h.dir, path)
+	if err := ioutil.WriteFile(path, []byte(contents), 0644); err != nil {
+		fatalf("failed to write file %v: %v", path, err)
+	}
+}
+
+func (h *hashTester) tempDir() string {
+	h.t.Helper()
+
+	td, err := ioutil.TempDir("", "gopherjs_hashTester")
+	if err != nil {
+		fatalf("failed to create temp dir: %v", err)
+	}
+
+	return td
+}
+
+func (h *hashTester) run(c string, args ...string) {
+	h.t.Helper()
+
+	cmd := exec.Command(c, args...)
+	cmd.Dir = h.dir
+	cmd.Env = h.env
+
+	out, err := cmd.CombinedOutput()
+	if err != nil {
+		fullCmd := append([]string{c}, args...)
+		fatalf("failed to run %v: %v\n%v", strings.Join(fullCmd, " "), err, string(out))
+	}
+}
+
+func fatalf(format string, args ...interface{}) {
+	panic(fmt.Errorf(format, args...))
+}
