more js stuff

https://github.com/Next-Flip/Momentum-Firmware/commits/js-backport-of-backport/

applications/system/js_app/examples/apps/Scripts/js_examples/path.js

@@ -2,7 +2,7 @@ let storage = require("storage");
 
 print("script has __dirpath of" + __dirpath);
 print("script has __filepath of" + __filepath);
-if (storage.exists(__dirpath + "/math.js")) {
+if (storage.fileExists(__dirpath + "/math.js")) {
     print("math.js exist here.");
 } else {
     print("math.js does not exist here.");

applications/system/js_app/examples/apps/Scripts/js_examples/storage.js

@@ -1,43 +1,29 @@
 let storage = require("storage");
 let path = "/ext/storage.test";
 
-function arraybuf_to_string(arraybuf) {
+print("File exists:", storage.fileExists(path));
-    let string = "";
-    let data_view = Uint8Array(arraybuf);
-    for (let i = 0; i < data_view.length; i++) {
-        string += chr(data_view[i]);
-    }
-    return string;
-}
-
-print("File exists:", storage.exists(path));
 
 print("Writing...");
-// write(path, data, offset)
+let file = storage.openFile(path, "w", "create_always");
-// If offset is specified, the file is not cleared, content is kept and data is written at specified offset
+file.write("Hello ");
-// Takes both strings and array buffers
+file.close();
-storage.write(path, "Hello ");
 
-print("File exists:", storage.exists(path));
+print("File exists:", storage.fileExists(path));
 
-// Append will create the file even if it doesnt exist!
+file = storage.openFile(path, "w", "open_append");
-// Takes both strings and array buffers
+file.write("World!");
-storage.append(path, "World!");
+file.close();
 
 print("Reading...");
-// read(path, size, offset)
+file = storage.openFile(path, "r", "open_existing");
-// If no size specified, total filesize is used
+let text = file.read("ascii", 128);
-// If offset is specified, size is capped at (filesize - offset)
+file.close();
-let data = storage.read(path);
+print(text);
-// read returns an array buffer, to allow proper usage of raw binary data
-print(arraybuf_to_string(data));
 
 print("Removing...")
 storage.remove(path);
 
 print("Done")
 
-// There's also:
+// You don't need to close the file after each operation, this is just to show some different ways to use
-// storage.copy(old_path, new_path);
+// There's also many more functions and options, check types docs in firmware repo
-// storage.move(old_path, new_path);
-// storage.mkdir(path);

applications/system/js_app/types/global.d.ts

@@ -56,6 +56,15 @@ declare const __filepath: string;
  */
 declare function load(path: string): any;
 
+/**
+ * @brief Return 1-byte string whose ASCII code is the integer `n`
+ * 
+ * If `n` is not numeric or outside of `0-255` range, `null` is returned
+ * 
+ * @param n The ASCII code to convert to string
+ */
+declare function chr(n: number): string | null;
+
 /**
  * @brief mJS Foreign Pointer type
  * 
@@ -189,6 +198,18 @@ declare class String {
      * See `charCodeAt`
      */
     at(index: number): number;
+    /**
+     * @brief Return index of first occurence of substr within the string or `-1` if not found
+     * @param substr The string to search for
+     * @param fromIndex The index to start searching from
+     */
+    indexOf(substr: string, fromIndex?: number): number;
+    /**
+     * @brief Return a substring between two indices
+     * @param start The index to start substring at
+     * @param end The index to end substring at
+     */
+    slice(start: number, end?: number): string;
 }
 
 declare class Boolean { }