Dynamic evaluation of conditions not using Eval()

Question

I need to be able to evaluate (True/False) some conditions not using Eval method. I came across this awesome technique which suits my needs: https://stackoverflow.com/a/68822307/9481833

Now I am trying to implement something like a Like operator and found the test function. Tried to amend the example as per the below but no joy:

const conditionalArray = [
  { name: "fridge", condition: "like", value: "sam" },
];

const dataTofilter = [
  { line: "Blah", revene: 3, sale: 2, fridge: "samsung" },
];

const conditions = {
  'like': (x, y) => x.test(/y/),
};

const result = dataTofilter.filter(data => {
  for (const el of conditionalArray) {
    if (!conditions[el.condition](data[el.name], el.value)) {
      return false;
    }
  }
  return true;
});

console.log(result);

Error message is that 'test' is not a function. Perhaps I'll need to handle this case in the filter codeblock at the bottom and look for the 'like' operator and handle it there ?

Answer 1

Therefore you should use match. I also fixed your like function so it won't match /y/ the literal but rather y the variable. Note: it needs escaping for RegExp.

const conditionalArray = [{
  name: "fridge",
  condition: "like",
  value: "sam"
}, ];

const dataTofilter = [{
  line: "Blah",
  revene: 3,
  sale: 2,
  fridge: "samsung"
}, ];

const conditions = {
  'like': (x, y) => x.match(new RegExp(y)),
};

const result = dataTofilter.filter(data => {
  for (const el of conditionalArray) {
    if (!conditions[el.condition](data[el.name], el.value)) {
      return false;
    }
  }
  return true;
});

console.log(result);