From 18286461b290b328e3305b9f7cd28220eacbde0a Mon Sep 17 00:00:00 2001
From: Ryan Lathouwers <ryanlath@pacbell.net>
Date: Sun, 3 Mar 2024 10:52:34 -0800
Subject: [PATCH] Add go1.16 embed.FS loader Addresses:
 https://github.com/CloudyKit/jet/issues/191

---
 go.mod                                        |  2 +-
 loaders/embedfs/embedfs_test.go               | 22 ++++++++++++
 loaders/embedfs/loader.go                     | 34 +++++++++++++++++++
 .../testData/includeIfNotExists/existent.jet  |  1 +
 .../testData/includeIfNotExists/exists.jet    |  1 +
 .../includeIfNotExists/ifIncludeIfExits.jet   |  8 +++++
 .../includeIfNotExists/notExistent.jet        |  1 +
 .../testData/includeIfNotExists/wcontext.jet  |  2 ++
 .../includeIfNotExists/wcontext_child.jet     |  1 +
 9 files changed, 71 insertions(+), 1 deletion(-)
 create mode 100644 loaders/embedfs/embedfs_test.go
 create mode 100644 loaders/embedfs/loader.go
 create mode 100644 loaders/embedfs/testData/includeIfNotExists/existent.jet
 create mode 100644 loaders/embedfs/testData/includeIfNotExists/exists.jet
 create mode 100644 loaders/embedfs/testData/includeIfNotExists/ifIncludeIfExits.jet
 create mode 100644 loaders/embedfs/testData/includeIfNotExists/notExistent.jet
 create mode 100644 loaders/embedfs/testData/includeIfNotExists/wcontext.jet
 create mode 100644 loaders/embedfs/testData/includeIfNotExists/wcontext_child.jet

diff --git a/go.mod b/go.mod
index 2703675..108eca7 100644
--- a/go.mod
+++ b/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
diff --git a/loaders/embedfs/embedfs_test.go b/loaders/embedfs/embedfs_test.go
new file mode 100644
index 0000000..160af7f
--- /dev/null
+++ b/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!")
+}
diff --git a/loaders/embedfs/loader.go b/loaders/embedfs/loader.go
new file mode 100644
index 0000000..7b85a5b
--- /dev/null
+++ b/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)
+}
diff --git a/loaders/embedfs/testData/includeIfNotExists/existent.jet b/loaders/embedfs/testData/includeIfNotExists/existent.jet
new file mode 100644
index 0000000..754eb15
--- /dev/null
+++ b/loaders/embedfs/testData/includeIfNotExists/existent.jet
@@ -0,0 +1 @@
+{{ includeIfExists: "exists.jet"}}
\ No newline at end of file
diff --git a/loaders/embedfs/testData/includeIfNotExists/exists.jet b/loaders/embedfs/testData/includeIfNotExists/exists.jet
new file mode 100644
index 0000000..7c07d61
--- /dev/null
+++ b/loaders/embedfs/testData/includeIfNotExists/exists.jet
@@ -0,0 +1 @@
+Hi, i exist!!
\ No newline at end of file
diff --git a/loaders/embedfs/testData/includeIfNotExists/ifIncludeIfExits.jet b/loaders/embedfs/testData/includeIfNotExists/ifIncludeIfExits.jet
new file mode 100644
index 0000000..fc31b2f
--- /dev/null
+++ b/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 }}
diff --git a/loaders/embedfs/testData/includeIfNotExists/notExistent.jet b/loaders/embedfs/testData/includeIfNotExists/notExistent.jet
new file mode 100644
index 0000000..a22998f
--- /dev/null
+++ b/loaders/embedfs/testData/includeIfNotExists/notExistent.jet
@@ -0,0 +1 @@
+{{ includeIfExists: "notExists.jet"}}
\ No newline at end of file
diff --git a/loaders/embedfs/testData/includeIfNotExists/wcontext.jet b/loaders/embedfs/testData/includeIfNotExists/wcontext.jet
new file mode 100644
index 0000000..95b8c20
--- /dev/null
+++ b/loaders/embedfs/testData/includeIfNotExists/wcontext.jet
@@ -0,0 +1,2 @@
+{{ includeIfExists("wcontext_child","Buddy") }}
+{{ includeIfExists("wcontext_child") }}
\ No newline at end of file
diff --git a/loaders/embedfs/testData/includeIfNotExists/wcontext_child.jet b/loaders/embedfs/testData/includeIfNotExists/wcontext_child.jet
new file mode 100644
index 0000000..076d6c3
--- /dev/null
+++ b/loaders/embedfs/testData/includeIfNotExists/wcontext_child.jet
@@ -0,0 +1 @@
+Hi, {{.}}!
\ No newline at end of file