1 files changed, 80 insertions, 0 deletions
diff --git a/internal/js/esbuild/sourcemap.go b/internal/js/esbuild/sourcemap.go
new file mode 100644
index 000000000..647f0c081
--- /dev/null
+++ b/internal/js/esbuild/sourcemap.go
@@ -0,0 +1,80 @@
+// Copyright 2024 The Hugo Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package esbuild
+
+import (
+	"encoding/json"
+	"strings"
+
+	"github.com/evanw/esbuild/pkg/api"
+	"github.com/gohugoio/hugo/common/paths"
+)
+
+type sourceMap struct {
+	Version        int      `json:"version"`
+	Sources        []string `json:"sources"`
+	SourcesContent []string `json:"sourcesContent"`
+	Mappings       string   `json:"mappings"`
+	Names          []string `json:"names"`
+}
+
+func fixOutputFile(o *api.OutputFile, resolve func(string) string) error {
+	if strings.HasSuffix(o.Path, ".map") {
+		b, err := fixSourceMap(o.Contents, resolve)
+		if err != nil {
+			return err
+		}
+		o.Contents = b
+	}
+	return nil
+}
+
+func fixSourceMap(s []byte, resolve func(string) string) ([]byte, error) {
+	var sm sourceMap
+	if err := json.Unmarshal([]byte(s), &sm); err != nil {
+		return nil, err
+	}
+
+	sm.Sources = fixSourceMapSources(sm.Sources, resolve)
+
+	b, err := json.Marshal(sm)
+	if err != nil {
+		return nil, err
+	}
+
+	return b, nil
+}
+
+func fixSourceMapSources(s []string, resolve func(string) string) []string {
+	var result []string
+	for _, src := range s {
+		if s := resolve(src); s != "" {
+			// Absolute filenames works fine on U*ix (tested in Chrome on MacOs), but works very poorly on Windows (again Chrome).
+			// So, convert it to a URL.
+			if u, err := paths.UrlFromFilename(s); err == nil {
+				result = append(result, u.String())
+			}
+		}
+	}
+	return result
+}
+
+// Used in tests.
+func SourcesFromSourceMap(s string) []string {
+	var sm sourceMap
+	if err := json.Unmarshal([]byte(s), &sm); err != nil {
+		return nil
+	}
+	return sm.Sources
+}