From 2a29bf624536c9daed25966dcaf80d840d0972c3 Mon Sep 17 00:00:00 2001
From: Solomon Hykes <solomon@dotcloud.com>
Date: Wed, 23 Oct 2013 08:35:26 +0000
Subject: [PATCH] Engine: basic testing harness

---
 engine/env_test.go  | 29 ++++++++++++++++++++++++++++
 engine/init_test.go | 46 +++++++++++++++++++++++++++++++++++++++++++++
 utils/random.go     | 16 ++++++++++++++++
 3 files changed, 91 insertions(+)
 create mode 100644 engine/env_test.go
 create mode 100644 engine/init_test.go
 create mode 100644 utils/random.go

diff --git a/engine/env_test.go b/engine/env_test.go
new file mode 100644
index 0000000000..3acbddad77
--- /dev/null
+++ b/engine/env_test.go
@@ -0,0 +1,29 @@
+package engine
+
+import (
+	"testing"
+)
+
+func TestNewJob(t *testing.T) {
+	job := mkJob(t, "dummy", "--level=awesome")
+	if job.Name != "dummy" {
+		t.Fatalf("Wrong job name: %s", job.Name)
+	}
+	if len(job.Args) != 1 {
+		t.Fatalf("Wrong number of job arguments: %d", len(job.Args))
+	}
+	if job.Args[0] != "--level=awesome" {
+		t.Fatalf("Wrong job arguments: %s", job.Args[0])
+	}
+}
+
+func TestSetenv(t *testing.T) {
+	job := mkJob(t, "dummy")
+	job.Setenv("foo", "bar")
+	if val := job.Getenv("foo"); val != "bar" {
+		t.Fatalf("Getenv returns incorrect value: %s", val)
+	}
+	if val := job.Getenv("nonexistent"); val != "" {
+		t.Fatalf("Getenv returns incorrect value: %s", val)
+	}
+}
diff --git a/engine/init_test.go b/engine/init_test.go
new file mode 100644
index 0000000000..b46e0bc9a1
--- /dev/null
+++ b/engine/init_test.go
@@ -0,0 +1,46 @@
+package engine
+
+import (
+	"testing"
+	"runtime"
+	"strings"
+	"fmt"
+	"io/ioutil"
+	"github.com/dotcloud/docker/utils"
+)
+
+var globalTestID string
+
+func init() {
+	Register("dummy", func(job *Job) string { return ""; })
+}
+
+func mkEngine(t *testing.T) *Engine {
+	// Use the caller function name as a prefix.
+	// This helps trace temp directories back to their test.
+	pc, _, _, _ := runtime.Caller(1)
+	callerLongName := runtime.FuncForPC(pc).Name()
+	parts := strings.Split(callerLongName, ".")
+	callerShortName := parts[len(parts)-1]
+	if globalTestID == "" {
+		globalTestID = utils.RandomString()[:4]
+	}
+	prefix := fmt.Sprintf("docker-test%s-%s-", globalTestID, callerShortName)
+	root, err := ioutil.TempDir("", prefix)
+	if err != nil {
+		t.Fatal(err)
+	}
+	eng, err := New(root)
+	if err != nil {
+		t.Fatal(err)
+	}
+	return eng
+}
+
+func mkJob(t *testing.T, name string, args ...string) *Job {
+	job, err := mkEngine(t).Job(name, args...)
+	if err != nil {
+		t.Fatal(err)
+	}
+	return job
+}
diff --git a/utils/random.go b/utils/random.go
new file mode 100644
index 0000000000..d5c37e44d0
--- /dev/null
+++ b/utils/random.go
@@ -0,0 +1,16 @@
+package utils
+
+import (
+	"io"
+	"crypto/rand"
+	"encoding/hex"
+)
+
+func RandomString() string {
+	id := make([]byte, 32)
+	_, err := io.ReadFull(rand.Reader, id)
+	if err != nil {
+		panic(err) // This shouldn't happen
+	}
+	return hex.EncodeToString(id)
+}