Fix recently introduced new data race in the shortcode handling

Fixes #1599

diff --git a/hugolib/shortcode.go b/hugolib/shortcode.go
index e65a859892b2b63d14e4f14eaa8c0906039abfcd..c49418b8562d72078d5e970b42137d965737b179 100644 (file)
--- a/hugolib/shortcode.go
+++ b/hugolib/shortcode.go
@@ -343,9 +343,14 @@ Loop:
                        if tmpl == nil {
                                return sc, fmt.Errorf("Unable to locate template for shortcode '%s' in page %s", sc.name, p.BaseFileName())
                        }
+
+                       // TODO(bep) Refactor/rename this lock strategy
+                       isInnerShortcodeCache.Lock()
                        if tmpl.Tree == nil {
+                               isInnerShortcodeCache.Unlock()
                                return sc, fmt.Errorf("Template for shortcode '%s' failed to compile for page '%s'", sc.name, p.BaseFileName())
                        }
+                       isInnerShortcodeCache.Unlock()
                        isInner = isInnerShortcode(tmpl)
 
                case tScParam: