Add safety barrier between concatenated javascript resources

diff --git a/hugolib/resource_chain_test.go b/hugolib/resource_chain_test.go
index 5a8ac22d78ea129783d4eb7f139de823386916b6..8f55e112e6856be7666f341c4a29d69402fddc8a 100644 (file)
--- a/hugolib/resource_chain_test.go
+++ b/hugolib/resource_chain_test.go
@@ -244,6 +244,13 @@ T2: Content: {{ $combinedText.Content }}|{{ $combinedText.RelPermalink }}
 {{ $css := "body { color: blue; }" | resources.FromString "styles.css" }}
 {{ $minified := resources.Get "css/styles1.css" | minify }}
 {{ slice $css $minified | resources.Concat "bundle/mixed.css" }} 
+{{/* https://github.com/gohugoio/hugo/issues/5403 */}}
+{{ $d := "function D {} // A comment" | resources.FromString "d.js"}}
+{{ $e := "(function E {})" | resources.FromString "e.js"}}
+{{ $f := "(function F {})()" | resources.FromString "f.js"}}
+{{ $jsResources := .Resources.Match "*.js" }}
+{{ $combinedJs := slice $d $e $f | resources.Concat "bundle/concatjs.js" }}
+T3: Content: {{ $combinedJs.Content }}|{{ $combinedJs.RelPermalink }}
 `)
                }, func(b *sitesBuilder) {
                        b.AssertFileContent("public/index.html", `T1: Content: ABC|RelPermalink: /bundle/concat.txt|Permalink: http://example.com/bundle/concat.txt|MediaType: text/plain`)
@@ -251,6 +258,17 @@ T2: Content: {{ $combinedText.Content }}|{{ $combinedText.RelPermalink }}
 
                        b.AssertFileContent("public/index.html", `T2: Content: t1t|t2t|`)
                        b.AssertFileContent("public/bundle/concattxt.txt", "t1t|t2t|")
+
+                       b.AssertFileContent("public/index.html", `T3: Content: function D {} // A comment
+;
+(function E {})
+;
+(function F {})()|`)
+                       b.AssertFileContent("public/bundle/concatjs.js", `function D {} // A comment
+;
+(function E {})
+;
+(function F {})()`)
                }},
                {"fromstring", func() bool { return true }, func(b *sitesBuilder) {
                        b.WithTemplates("home.html", `

diff --git a/resources/resource_factories/bundler/bundler.go b/resources/resource_factories/bundler/bundler.go
index ca0ccf86ee17c33398ce9a83759484c31b44eecc..59810e34741ede0e4e5aef2ca9eeb8f46d2f1540 100644 (file)
--- a/resources/resource_factories/bundler/bundler.go
+++ b/resources/resource_factories/bundler/bundler.go
@@ -15,6 +15,7 @@
 package bundler
 
 import (
+       "bytes"
        "fmt"
        "io"
        "path/filepath"
@@ -92,12 +93,30 @@ func (c *Client) Concat(targetPath string, r resource.Resources) (resource.Resou
                                        }
                                        return nil, err
                                }
+
                                rcsources = append(rcsources, rc)
                        }
 
-                       readers := make([]io.Reader, len(rcsources))
-                       for i := 0; i < len(rcsources); i++ {
-                               readers[i] = rcsources[i]
+                       var readers []io.Reader
+
+                       // Arbitrary JavaScript files require a barrier between them to be safely concatenated together.
+                       // Without this, the last line of one file can affect the first line of the next file and change how both files are interpreted.
+                       if resolvedm.MainType == media.JavascriptType.MainType && resolvedm.SubType == media.JavascriptType.SubType {
+                               readers = make([]io.Reader, 2*len(rcsources)-1)
+                               j := 0
+                               for i := 0; i < len(rcsources); i++ {
+                                       if i > 0 {
+                                               readers[j] = bytes.NewBufferString("\n;\n")
+                                               j++
+                                       }
+                                       readers[j] = rcsources[i]
+                                       j++
+                               }
+                       } else {
+                               readers = make([]io.Reader, len(rcsources))
+                               for i := 0; i < len(rcsources); i++ {
+                                       readers[i] = rcsources[i]
+                               }
                        }
 
                        mr := io.MultiReader(readers...)