// This works by proxying every function call and wrapping a try-catch block to filter out redundant and confusing | |
// `RuntimeError: unreachable` exceptions that would normally be printed in the browser's JS console upon a panic. | |
export function panicProxy<T extends object>(module: T): T { | |
const proxyHandler = { | |
get(target: T, propKey: string | symbol, receiver: unknown): unknown { | |
const targetValue = Reflect.get(target, propKey, receiver); | |
// Keep the original value being accessed if it isn't a function | |
const isFunction = typeof targetValue === "function"; | |
if (!isFunction) return targetValue; | |
// Special handling to wrap the return of a constructor in the proxy | |
const isClass = isFunction && /^\s*class\s+/.test(targetValue.toString()); | |
if (isClass) { | |
// eslint-disable-next-line func-names | |
return function (...args: unknown[]): unknown { | |
// All three of these comment lines are necessary to suppress errors at both compile time and while editing this file (@ts-expect-error doesn't work here while editing the file) | |
// eslint-disable-next-line @typescript-eslint/ban-ts-comment | |
// @ts-ignore | |
// eslint-disable-next-line new-cap | |
const result = new targetValue(...args); | |
return panicProxy(result); | |
}; | |
} | |
// Replace the original function with a wrapper function that runs the original in a try-catch block | |
// eslint-disable-next-line func-names | |
return function (...args: unknown[]): unknown { | |
let result; | |
try { | |
// @ts-expect-error TypeScript does not know what `this` is, since it should be able to be anything | |
result = targetValue.apply(this, args); | |
} catch (err) { | |
// Suppress `unreachable` WebAssembly.RuntimeError exceptions | |
if (!String(err).startsWith("RuntimeError: unreachable")) throw err; | |
} | |
return result; | |
}; | |
}, | |
}; | |
return new Proxy<T>(module, proxyHandler); | |
} | |