feat: fix missing createWritable in safari

[jimmywarting]

Safari do have a OPFS but it's lacking any good method of writing things to it unless you are not using the syncAccessHandle that's only available in web workers.

This will patch/repair/polyfill the missing features in the broken api.

• FileSystemWritableFileStream is added to global scope only if it dose not exist but a File system dose.
• FileSystemFileHandle.prototype.createWritable is conditionally polyfilled if needed.
  • note that this will also patch getFileHandle to keep track of what the parent directory is as createWritable needs to know the path of where it's located in order to re-create the FileSystemFile handle inside of a worker ( cuz they can't be structural cloned / postMessaged )
• Safari did also lacked some assertion test to see if the file/folder still existed before doing some kind of operation on them. so some methods have been patched to ensure that they do still exist

[Mazuh]

@jimmywarting any estimate of when you'll publish a stable version on NPM including this fix?

[jimmywarting]

oh... did i forget to publish?

sry about that. i have nothing else in the work that needs to be completed. expect a new release soon-ish

[SargisPlusPlus]

@jimmywarting I had an issue with this... I published the library myself to test out this code.
In my react app, I have:

          const opfsRoot = await getOriginPrivateDirectory();
          const userDir = await opfsRoot.getDirectoryHandle('123', {
            create: true,
          });
           const fileHandle = await userDir.getFileHandle('test.txt', {
              create: true,
           });
          try {
            const writable = await fileHandle.createWritable();
          } catch (e) {
            console.log('****', e);
          }

This works in Chrome. But Safari (17.2) throws an error: **** NotFoundError: A requested file or directory could not be found at the time an operation was processed.

UPDATE: I think I may have found the issue. See comments.

[SargisPlusPlus]

@jimmywarting path was null for me. I had to swap these two.

const path = await root.resolve(parent)

[SargisPlusPlus]

another issue here...
not sure why but

code.toString() + `;${code.name}();`

produces:
function() {....}
which throws a syntax error because function doesnt have name.

To solve this, i change code to be arrow function:

  const code = () => { ... }

and then here I have:

      const stringCode = `(${code.toString()})()`;
      const blob = new Blob([stringCode], {

which produces:

(() => {...})()

And this works.