Add go1.16 embed.FS loader

Addresses: CloudyKit#191

go.mod

@@ -1,5 +1,5 @@
 module github.com/CloudyKit/jet/v6
 
-go 1.12
+go 1.16
 
 require github.com/CloudyKit/fastprinter v0.0.0-20200109182630-33d98a066a53

loaders/embedfs/embedfs_test.go

@@ -0,0 +1,22 @@
+package embedfs
+
+import (
+	"embed"
+	"testing"
+
+	"github.com/CloudyKit/jet/v6"
+	"github.com/CloudyKit/jet/v6/jettest"
+)
+
+//go:embed testData/includeIfNotExists/*
+var templateFS embed.FS
+
+func TestEmbedFileSystemResolve(t *testing.T) {
+	l := NewLoader("testData/includeIfNotExists", templateFS)
+
+	set := jet.NewSet(l)
+	jettest.RunWithSet(t, set, nil, nil, "existent", "Hi, i exist!!")
+	jettest.RunWithSet(t, set, nil, nil, "notExistent", "")
+	jettest.RunWithSet(t, set, nil, nil, "ifIncludeIfExits", "Hi, i exist!!\n    Was included!!\n\n\n    Was not included!!\n\n")
+	jettest.RunWithSet(t, set, nil, "World", "wcontext", "Hi, Buddy!\nHi, World!")
+}

loaders/embedfs/loader.go

@@ -0,0 +1,34 @@
+package embedfs
+
+import (
+	"embed"
+	"io"
+	"os"
+	"path/filepath"
+
+	"github.com/CloudyKit/jet/v6"
+)
+
+type embedFileSystemLoader struct {
+	dir string
+	fs embed.FS
+}
+
+// NewLoader returns an initialized loader serving the passed embed.FS.
+func NewLoader(dirPath string, fs embed.FS) jet.Loader {
+	return &embedFileSystemLoader{
+		dir: filepath.FromSlash(dirPath),
+		fs: fs,
+	}
+}
+
+// Open implements Loader.Open() on top of an embed.FS.
+func (l *embedFileSystemLoader) Open(name string) (io.ReadCloser, error) {
+	return l.fs.Open(filepath.Join(l.dir, filepath.FromSlash(name)))
+}
+
+// Exists implements Loader.Exists() on top of an embed.FS by trying to open the file.
+func (l *embedFileSystemLoader) Exists(name string) bool {
+	_, err := l.fs.Open(filepath.Join(l.dir, filepath.FromSlash(name)))
+	return err == nil && !os.IsNotExist(err)
+}

loaders/embedfs/testData/includeIfNotExists/existent.jet

@@ -0,0 +1 @@
+{{ includeIfExists: "exists.jet"}}

loaders/embedfs/testData/includeIfNotExists/exists.jet

@@ -0,0 +1 @@
+Hi, i exist!!

loaders/embedfs/testData/includeIfNotExists/ifIncludeIfExits.jet

@@ -0,0 +1,8 @@
+{{ if includeIfExists("exists.jet") }}
+    Was included!!
+{{ end }}
+{{ if includeIfExists("notExists.jet") }}
+    Was included!!
+{{ else }}
+    Was not included!!
+{{ end }}

loaders/embedfs/testData/includeIfNotExists/notExistent.jet

@@ -0,0 +1 @@
+{{ includeIfExists: "notExists.jet"}}

loaders/embedfs/testData/includeIfNotExists/wcontext.jet

@@ -0,0 +1,2 @@
+{{ includeIfExists("wcontext_child","Buddy") }}
+{{ includeIfExists("wcontext_child") }}

loaders/embedfs/testData/includeIfNotExists/wcontext_child.jet

@@ -0,0 +1 @@
+Hi, {{.}}!