Added MemoryLoader and test.

loader.go

@@ -14,15 +14,16 @@ type Loader interface {
 }
 
 type stringTemplate struct {
+	name     string
 	contents string
 }
 
 func (t *stringTemplate) Name() string {
-	return t.contents
+	return t.name
 }
 
 func (t *stringTemplate) Contents() io.Reader {
-	return bytes.NewReader([]byte(t.contents))
+	return bytes.NewBufferString(t.contents)
 }
 
 // StringLoader is intended to be used to load Stick templates directly from a string.
@@ -30,7 +31,21 @@ type StringLoader struct{}
 
 // Load on a StringLoader simply returns the name that is passed in.
 func (l *StringLoader) Load(name string) (Template, error) {
-	return &stringTemplate{name}, nil
+	return &stringTemplate{name, name}, nil
+}
+
+// MemoryLoader loads templates from an in-memory map.
+type MemoryLoader struct {
+	Templates map[string]string
+}
+
+// Load tries to load the template from the in-memory map.
+func (l *MemoryLoader) Load(name string) (Template, error) {
+	v, ok := l.Templates[name]
+	if !ok {
+		return nil, os.ErrNotExist
+	}
+	return &stringTemplate{name, v}, nil
 }
 
 type fileTemplate struct {

loader_test.go

@@ -1,6 +1,7 @@
 package stick
 
 import (
+	"io/ioutil"
 	"os"
 	"testing"
 )
@@ -32,3 +33,20 @@ func TestStringLoader(t *testing.T) {
 		t.Errorf("unexpected template name: %s", b.Name())
 	}
 }
+
+func TestMemoryLoader(t *testing.T) {
+	l := &MemoryLoader{map[string]string{"test.twig": "some text"}}
+	b, e := l.Load("test.twig")
+	if e != nil {
+		t.Fatalf("expected load to succeed got %s", e)
+	} else if b.Name() != "test.twig" {
+		t.Fatalf("expected to load test.twig got %s", b.Name())
+	}
+	s, e := ioutil.ReadAll(b.Contents())
+	if e != nil {
+		t.Fatalf("unexpected error %s", e)
+	}
+	if string(s) != "some text" {
+		t.Fatalf("expected 'some text' got '%s'", string(s))
+	}
+}