"Golden file" testing pattern

cmd/dep/ensure_test.go

@@ -5,6 +5,7 @@
 package main
 
 import (
+	"strings"
 	"testing"
 
 	"github.com/golang/dep/test"
@@ -21,72 +22,25 @@ func TestEnsureOverrides(t *testing.T) {
 	h.TempDir("src")
 	h.Setenv("GOPATH", h.Path("."))
 
-	m := `package main
-
-import (
-	"github.com/Sirupsen/logrus"
-	sthing "github.com/sdboyer/dep-test"
-)
-
-type Baz sthing.Foo
-
-func main() {
-	logrus.Info("hello world")
-}`
-
-	h.TempFile("src/thing/thing.go", m)
+	h.TempCopy("src/thing/thing.go", "ensure_test/source1.go")
 	h.Cd(h.Path("src/thing"))
 
 	h.Run("init")
 	h.Run("ensure", "-override", "github.com/Sirupsen/[email protected]")
 
-	expectedManifest := `{
-    "overrides": {
-        "github.com/Sirupsen/logrus": {
-            "version": "0.11.0"
-        }
-    }
-}
-`
-
+	expectedManifest := h.GetTestfile("ensure_test/exp_manifest1.json")
 	manifest := h.ReadManifest()
-	if manifest != expectedManifest {
+	if exp, err := test.AreEqualJSON(expectedManifest, manifest); !exp {
+		h.Must(err)
 		t.Fatalf("expected %s, got %s", expectedManifest, manifest)
 	}
 
 	sysCommit := h.GetCommit("go.googlesource.com/sys")
-	expectedLock := `{
-    "memo": "57d20ba0289c2df60025bf6127220a5403483251bd5e523a7f9ea17752bd5482",
-    "projects": [
-        {
-            "name": "github.com/Sirupsen/logrus",
-            "version": "v0.11.0",
-            "revision": "d26492970760ca5d33129d2d799e34be5c4782eb",
-            "packages": [
-                "."
-            ]
-        },
-        {
-            "name": "github.com/sdboyer/dep-test",
-            "version": "1.0.0",
-            "revision": "2a3a211e171803acb82d1d5d42ceb53228f51751",
-            "packages": [
-                "."
-            ]
-        },
-        {
-            "name": "golang.org/x/sys",
-            "branch": "master",
-            "revision": "` + sysCommit + `",
-            "packages": [
-                "unix"
-            ]
-        }
-    ]
-}
-`
+	expectedLock := h.GetTestfile("ensure_test/exp_lock1.json")
+	expectedLock = strings.Replace(expectedLock, "{{sysCommit}}", sysCommit, -1)
 	lock := h.ReadLock()
-	if lock != expectedLock {
+	if exp, err := test.AreEqualJSON(expectedLock, lock); !exp {
+		h.Must(err)
 		t.Fatalf("expected %s, got %s", expectedLock, lock)
 	}
 }

cmd/dep/testdata/ensure_test/exp_lock1.json

@@ -0,0 +1,29 @@
+{
+  "memo": "57d20ba0289c2df60025bf6127220a5403483251bd5e523a7f9ea17752bd5482",
+  "projects": [
+      {
+          "name": "github.com/Sirupsen/logrus",
+          "version": "v0.11.0",
+          "revision": "d26492970760ca5d33129d2d799e34be5c4782eb",
+          "packages": [
+              "."
+          ]
+      },
+      {
+          "name": "github.com/sdboyer/dep-test",
+          "version": "1.0.0",
+          "revision": "2a3a211e171803acb82d1d5d42ceb53228f51751",
+          "packages": [
+              "."
+          ]
+      },
+      {
+          "name": "golang.org/x/sys",
+          "branch": "master",
+          "revision": "{{sysCommit}}",
+          "packages": [
+              "unix"
+          ]
+      }
+  ]
+}

cmd/dep/testdata/ensure_test/exp_manifest1.json

@@ -0,0 +1,7 @@
+{
+  "overrides": {
+      "github.com/Sirupsen/logrus": {
+          "version": "0.11.0"
+      }
+  }
+}

cmd/dep/testdata/ensure_test/source1.go

@@ -0,0 +1,12 @@
+package main
+
+import (
+	"github.com/Sirupsen/logrus"
+	sthing "github.com/sdboyer/dep-test"
+)
+
+type Baz sthing.Foo
+
+func main() {
+	logrus.Info("hello world")
+}

test/test.go

@@ -36,6 +36,7 @@ type Helper struct {
 	t              *testing.T
 	temps          []string
 	wd             string
+	origWd         string
 	env            []string
 	tempdir        string
 	ran            bool
@@ -45,7 +46,8 @@ type Helper struct {
 
 // NewHelper initializes a new helper for testing.
 func NewHelper(t *testing.T) *Helper {
-	return &Helper{t: t}
+	wd, _ := os.Getwd()
+	return &Helper{t: t, origWd: wd}
 }
 
 // Must gives a fatal error if err is not nil.
@@ -414,6 +416,36 @@ func (h *Helper) TempFile(path, contents string) {
 	h.Must(ioutil.WriteFile(filepath.Join(h.tempdir, path), bytes, 0644))
 }
 
+// Location of test data
+const _TEST_DATA_LOCATION = "cmd/dep/testdata"
+
+// GetTestfile reads a file form the testdata directory into memory.  src is
+// relative to ./testdata.  Assumes tests take place starting in the cmd/dep
+// directory.
+func (h *Helper) GetTestfile(src string) string {
+	content, err := ioutil.ReadFile(filepath.Join(h.origWd, "testdata", src))
+	if err != nil {
+		panic(err)
+	}
+	if strings.HasSuffix(src, ".go") {
+		formatted, err := format.Source(content)
+		if err == nil {
+			content = formatted
+		}
+	}
+	return string(content)
+}
+
+// TempCopy copies a temporary file from testdata into the temporary directory.
+// dest is relative to the temp directory location, and src is relative to
+// ./testdata.  Assumes tests take place starting in the cmd/dep directory.
+func (h *Helper) TempCopy(dest, src string) {
+	content := h.GetTestfile(src)
+	h.makeTempdir()
+	h.Must(os.MkdirAll(filepath.Join(h.tempdir, filepath.Dir(dest)), 0755))
+	h.Must(ioutil.WriteFile(filepath.Join(h.tempdir, dest), []byte(content), 0644))
+}
+
 // TempDir adds a temporary directory for a run of testgo.
 func (h *Helper) TempDir(path string) {
 	h.makeTempdir()

test/util.go

@@ -0,0 +1,22 @@
+package test
+
+import (
+	"bytes"
+	"encoding/json"
+)
+
+func AreEqualJSON(s1, s2 string) (bool, error) {
+	var o1 interface{}
+	var o2 interface{}
+	var err error
+
+	if err = json.Unmarshal([]byte(s1), &o1); err != nil {
+		return false, err
+	}
+	if err = json.Unmarshal([]byte(s2), &o2); err != nil {
+		return false, err
+	}
+	b1, _ := json.Marshal(o1)
+	b2, _ := json.Marshal(o2)
+	return bytes.Equal(b1, b2), nil
+}