Builds / serves multiple HTML files.

lib/src/utils.dart

Index: lib/src/utils.dart
diff --git a/lib/src/utils.dart b/lib/src/utils.dart
index 6f92e2252729d004693d5977fbc2ef885af6e279..b1794f63cc3e2adffd0e1d35a83c8682d6ed30e8 100644
--- a/lib/src/utils.dart
+++ b/lib/src/utils.dart
@@ -314,7 +314,12 @@ String resourceOutputPath(Uri resourceUri, Uri entryUri, String runtimeDir) {
 
   if (resourceUri.scheme != 'file') return null;
 
-  var entryDir = path.dirname(entryUri.path);
+  var entryPath = entryUri.path;
+  // The entry uri is either a directory or a dart/html file.  If the latter,
+  // trim the file.
+  var entryDir = entryPath.endsWith('.dart') || entryPath.endsWith('.html')
+      ? path.dirname(entryPath)
+      : entryPath;
   var filepath = path.normalize(path.join(entryDir, resourceUri.path));
   if (path.isWithin(runtimeDir, filepath)) {
     filepath = path.relative(filepath, from: runtimeDir);