codekingpro/portable-devtools

1const { serializeError } = require('./error')
2
3const deepMap = (input, handler = v => v, path = ['$'], seen = new Set([input])) => {
4  // this is in an effort to maintain bole's error logging behavior
5  if (path.join('.') === '$' && input instanceof Error) {
6    return deepMap({ err: serializeError(input) }, handler, path, seen)
7  }
8  if (input instanceof Error) {
9    return deepMap(serializeError(input), handler, path, seen)
10  }
11  // allows for non-node js environments, sush as workers
12  if (typeof Buffer !== 'undefined' && input instanceof Buffer) {
13    return `[unable to log instanceof buffer]`
14  }
15  if (input instanceof Uint8Array) {
16    return `[unable to log instanceof Uint8Array]`
17  }
18
19  if (Array.isArray(input)) {
20    const result = []
21    for (let i = 0; i < input.length; i++) {
22      const element = input[i]
23      const elementPath = [...path, i]
24      if (element instanceof Object) {
25        if (!seen.has(element)) { // avoid getting stuck in circular reference
26          seen.add(element)
27          result.push(deepMap(handler(element, elementPath), handler, elementPath, seen))
28        }
29      } else {
30        result.push(handler(element, elementPath))
31      }
32    }
33    return result
34  }
35
36  if (input === null) {
37    return null
38  } else if (typeof input === 'object' || typeof input === 'function') {
39    const result = {}
40
41    for (const propertyName of Object.getOwnPropertyNames(input)) {
42    // skip logging internal properties
43      if (propertyName.startsWith('_')) {
44        continue
45      }
46
47      try {
48        const property = input[propertyName]
49        const propertyPath = [...path, propertyName]
50        if (property instanceof Object) {
51          if (!seen.has(property)) { // avoid getting stuck in circular reference
52            seen.add(property)
53            result[propertyName] = deepMap(
54              handler(property, propertyPath), handler, propertyPath, seen
55            )
56          }
57        } else {
58          result[propertyName] = handler(property, propertyPath)
59        }
60      } catch (err) {
61      // a getter may throw an error
62        result[propertyName] = `[error getting value: ${err.message}]`
63      }
64    }
65    return result
66  }
67
68  return handler(input, path)
69}
70
71module.exports = { deepMap }
72