Library throws strings instead of error objects

[SimonSchick]

This is pretty bad because it makes it impossible to trace errors.

I think it would be a relatively easy fix here https://github.com/UrielCh/opencv4nodejs/blob/master/cc/native-node-utils/TryCatch.h#L32 unfortunately my CPP game is terrible and I've never worked on any CPP node modules.

[SimonSchick]

Repro: new (require('@u4/opencv4nodejs').Mat)().getDataAsArray()

[UrielCh]

Thank you for pointing out the file that needs correction. I'm currently facing homelessness, so I'll address that once I've resolved this pressing issue.

[SimonSchick]

Hey, I hope you're doing better, I'm interested in contributing, would you be able to provide some pointers on how to resolve this issue? Right now our workaround looks like this:

// Manually patch all opencv.* opencv.Mat/Contour.prototype.* methods to not throw strings

import * as cv from 'opencv4nodejs';

export class OpenCVWrappedError extends Error {
  public override name = 'OpenCVWrappedError';
  public constructor(
    message: string,
    public readonly functionName: string
  ) {
    super(`${functionName}: ${message}`);
  }
}

const patchNoThrowString = (obj: Record<string, unknown>) => {
  for (const [key, value] of Object.entries(obj)) {
    // ignore what is likely classes
    if (
      typeof value !== 'function' ||
      key[0]!.toUpperCase() === key[0] ||
      !!Object.keys(value.prototype as object).length
    ) {
      continue;
    }

    // eslint-disable-next-line unicorn/prefer-ternary
    if (key.endsWith('Async')) {
      // we specifically use a different name, `jest` in it's infinite wisdom resets js modules but NOT native modules
      // which leads to opencv loading multiple times but not it's bindings
      // further it relies on `.prototype.constructor.name` being present thus this function cannot be async...
      // eslint-disable-next-line @typescript-eslint/promise-function-async
      obj[key] = function asyncProxy(...args: unknown[]) {
        // eslint-disable-next-line @typescript-eslint/return-await
        return (value as (...args: unknown[]) => Promise<unknown>)
          .call(this, ...args)
          .catch((error: unknown) => {
            if (typeof error === 'string') {
              throw new OpenCVWrappedError(error, key);
            }
            throw error;
          });
      };
    } else {
      obj[key] = function proxy(...args: unknown[]): unknown {
        try {
          return value.call(this, ...args) as unknown;
        } catch (error) {
          if (typeof error === 'string') {
            throw new OpenCVWrappedError(error, key);
          }
          throw error;
        }
      };
    }
  }
};

// eslint-disable-next-line @typescript-eslint/no-var-requires, @typescript-eslint/no-require-imports
patchNoThrowString(require('opencv4nodejs') as Record<string, unknown>);
patchNoThrowString(cv.Mat.prototype as unknown as Record<string, unknown>);
patchNoThrowString(cv.Contour.prototype as unknown as Record<string, unknown>);