Update readme

README.md

@@ -27,6 +27,7 @@ You can pass options to `metalsmith-in-place` with the [Javascript API](https://
 * [pattern](#pattern): optional. Only files that match this pattern will be processed. Accepts a string or an array of strings. The default is `**`.
 * [engineOptions](#engineoptions): optional. Use this to pass options to the jstransformer that's rendering your files. The default is `{}`.
 * [suppressNoFilesError](#suppressnofileserror): optional. The no-files-to-process error will be suppressed. The default is `false`.
+* [setFilename](#setfilename): optional. Some templating engines, like [pug](https://github.com/pugjs/pug), need a `filename` property to be present in the options to be able to process relative includes, extends and the like. Setting this option to true will add the current filename to the options passed to each jstransformer. The default is `false`.
 
 ### `pattern`
 
@@ -71,9 +72,39 @@ Would pass `{ "cache": false }` to each used jstransformer.
 
 ### `suppressNoFilesError`
 
-`metalsmith-in-place` throws [an error](#no-files-to-process) if it can’t find any files to process. If you’re doing any kind of incremental builds via something like `metalsmith-watch`, this is problematic as you’re likely only rebuilding files that have changed. This flag allows you to suppress that error ([more info](https://github.com/metalsmith/metalsmith-in-place/pull/151)).
+`metalsmith-in-place` exits with [an error](#no-files-to-process) if it can’t find any files to process. If you’re doing any kind of incremental builds via something like `metalsmith-watch`, this is problematic as you’re likely only rebuilding files that have changed. This flag allows you to suppress that error. So this `metalsmith.json`:
 
-Note that if you have [debugging](#errors-and-debugging) turned on, you’ll see a message denoting that no files are present for processing.
+```json
+{
+  "source": "src",
+  "destination": "build",
+  "plugins": {
+    "metalsmith-in-place": {
+      "suppressNoFilesError": true
+    }
+  }
+}
+```
+
+Would suppress the error if there aren't any files to process. Note that when this option is turned on, if you're logging [debug messages](#errors-and-debugging), you’ll still see a message denoting when there aren't any files for metalsmith-layouts to process.
+
+### `setFilename`
+
+Set this option to `true` if you want to pass the current filename to each jstransformer. The default is `false`. So this `metalsmith.json`:
+
+```json
+{
+  "source": "src",
+  "destination": "build",
+  "plugins": {
+    "metalsmith-in-place": {
+      "setFilename": true
+    }
+  }
+}
+```
+
+Would overwrite `engineOptions.filename` with the absolute path for the file that's currently being processed, and pass that to the jstransformer. For now we're just passing `filename`, but if you encounter a jstransformer that requires a different property, like `path` or something else, let us know and we can add it.
 
 ## Errors and debugging