Better fix for #2278. Fixes #1038

src/TemplatePassthrough.js

@@ -67,10 +67,14 @@ class TemplatePassthrough {
       TemplatePath.join(outputDir, outputPath)
     );
 
-    if (this.isIncremental && TemplatePath.isDirectorySync(fullOutputPath)) {
+    if (
+      fs.existsSync(inputPath) &&
+      !TemplatePath.isDirectorySync(inputPath) &&
+      TemplatePath.isDirectorySync(fullOutputPath)
+    ) {
       let filename = path.parse(inputPath).base;
       return TemplatePath.normalize(
-        TemplatePath.join(outputDir, outputPath, filename)
+        TemplatePath.join(fullOutputPath, filename)
       );
     }
 
@@ -141,7 +145,7 @@ class TemplatePassthrough {
    */
   async copy(src, dest, copyOptions) {
     if (
-      !TemplatePath.stripLeadingDotSlash(dest).includes(
+      !TemplatePath.stripLeadingDotSlash(dest).startsWith(
         TemplatePath.stripLeadingDotSlash(this.outputDir)
       )
     ) {

test/TemplatePassthroughTest.js

@@ -299,12 +299,22 @@ test("Output paths match with different templatePassthrough methods", async (t)
 //   t.is(pass.getOutputPath(), "_site/rename.js");
 // });
 
-test("Bug with incremental copying to a directory output, issue #2278", async (t) => {
+test("Bug with incremental file copying to a directory output, issue #2278 #1038", async (t) => {
   let pass1 = getTemplatePassthrough(
-    { inputPath: "./public/test.css", outputPath: "/" },
+    { inputPath: "./test/stubs/public/test.css", outputPath: "/" },
     "test/stubs",
     "."
   );
-  pass1.setIsIncremental(true);
+
   t.is(pass1.getOutputPath(), "test/stubs/test.css");
 });
+
+test("Bug with incremental dir copying to a directory output, issue #2278 #1038", async (t) => {
+  let pass1 = getTemplatePassthrough(
+    { inputPath: "./test/stubs/public/", outputPath: "/" },
+    "test/stubs",
+    "."
+  );
+
+  t.is(pass1.getOutputPath(), "test/stubs");
+});