common/maps: Add Scratch.Values

Fixes gohugoio#7335

common/maps/scratch.go

@@ -107,6 +107,15 @@ func (c *Scratch) Get(key string) interface{} {
 	return val
 }
 
+// Values returns the raw backing map. Note that you should just use
+// this method on the locally scoped Scratch instances you obtain via newScratch, not
+// .Page.Scratch etc., as that will lead to concurrency issues.
+func (c *Scratch) Values() map[string]interface{} {
+	c.mu.RLock()
+	defer c.mu.RUnlock()
+	return c.values
+}
+
 // SetInMap stores a value to a map with the given key in the Node context.
 // This map can later be retrieved with GetSortedMapValues.
 func (c *Scratch) SetInMap(key string, mapKey string, value interface{}) string {
@@ -147,7 +156,7 @@ func (c *Scratch) GetSortedMapValues(key string) interface{} {
 	return sortedArray
 }
 
-// NewScratch returns a new instance Scratch.
+// NewScratch returns a new instance of Scratch.
 func NewScratch() *Scratch {
 	return &Scratch{values: make(map[string]interface{})}
 }

common/maps/scratch_test.go

@@ -47,6 +47,9 @@ func TestScratchAdd(t *testing.T) {
 	scratch.Add("scratch", scratch)
 	_, err := scratch.Add("scratch", scratch)
 
+	m := scratch.Values()
+	c.Assert(m, qt.HasLen, 5)
+
 	if err == nil {
 		t.Errorf("Expected error from invalid arithmetic")
 	}

docs/content/en/functions/scratch.md

@@ -113,6 +113,11 @@ Removes the given key
 {{ .Scratch.Delete "greetings" }}
 ```
 
+#### .Values
+
+`Values` returns the raw backing map. Note that you should just use this method on the locally scoped `Scratch` instances you obtain via `newScratch`, not
+ `.Page.Scratch` etc., as that will lead to concurrency issues.
+
 ## Scope
 The scope of the backing data is global for the given `Page` or `Shortcode`, and spans partial and shortcode includes.