Using packages/asm in-browser

[shazow]

Hiya @ricmoo, I'm building a fun library to extract some attributes from EVM bytecode (such as function selectors) and it has been super convenient to use your experimental asm package (particularly the Opcodes set, and the disassemble helper).

Unfortunately I noticed that some of the code makes assumptions that it's a command-line library rather than a browser-runnable one, so I'm having trouble getting it to build in my demo frontend using Vite. My browser js packaging-fu is weak so maybe it's just me, but the symptom is errors like 'dirname' is not exported by __vite-browser-external which stack traces to @ethersproject/asm.

I pulled in a local fork of just opcodes.ts and the relevant helper, and that's working for me, so I'm wondering which approach you'd prefer?

1. Should I just vendor the relevant subset of things I need? (And of course include credits/LICENSE/etc)
2. Is there a way to override things like dirname so that it still builds for browser targets?
3. Are there changes you'd like to see to the asm package to make it usable as an in-browser library by pulling out the cli-specific stuff?

Edit: I have a feeling this is mostly a failure of my bundling process, any protips appreciated. :)

[shazow]

Pretty sure sure this is a Vite-specific issue, might just switch to a different frontend framework for now. :)

[shazow]

Nope doesn't look too Vite-specific, esbuild and other things I've tried are running into similar issues.

✘ [ERROR] Could not resolve "path"

    node_modules/@ethersproject/asm/lib.esm/assembler.js:15:33:
      15 │ import { dirname, resolve } from "path";
         ╵                                  ~~~~~~

  The package "path" wasn't found on the file system but is built into node. Are you trying to
  bundle for node? You can use "--platform=node" to do that, which will remove this error.

✘ [ERROR] Could not resolve "vm"

    node_modules/@ethersproject/asm/lib.esm/assembler.js:16:15:
      16 │ import vm from "vm";
         ╵                ~~~~

  The package "vm" wasn't found on the file system but is built into node. Are you trying to bundle
  for node? You can use "--platform=node" to do that, which will remove this error.

✘ [ERROR] Could not resolve "fs"

    node_modules/@ethersproject/asm/lib.esm/_parser.js:776:25:
      776 │     var source = require('fs').readFileSync(require('path').normalize(args[1]), "utf8");
          ╵                          ~~~~

  The package "fs" wasn't found on the file system but is built into node. Are you trying to bundle
  for node? You can use "--platform=node" to do that, which will remove this error.

✘ [ERROR] Could not resolve "path"

    node_modules/@ethersproject/asm/lib.esm/_parser.js:776:52:
      776 │     var source = require('fs').readFileSync(require('path').normalize(args[1]), "utf8");
          ╵                                                     ~~~~~~

  The package "path" wasn't found on the file system but is built into node. Are you trying to
  bundle for node? You can use "--platform=node" to do that, which will remove this error.

Thinking I'll pull out some small part of the asm package and rewrite the rest.