--description--

In this lab, you will create a function that performs a search and replace on the sentence using the arguments provided and then returns the new sentence.

Note: Preserve the case of the first character in the original word when you are replacing it. For example if you mean to replace the word Book with the word dog, it should be replaced as Dog

Objective: Fulfill the user stories below and get all the tests to pass to complete the lab.

User Stories:

1. You should create a function named myReplace.
2. The myReplace function should take three arguments: a string, a word to be replaced, and the word to replace it with.
3. The myReplace function should return the new string with the replacement.
4. You should preserve the case of the first character in the original word when you are replacing it.

--hints--

You should create a function named myReplace.

assert.isFunction(myReplace);

myReplace should take three arguments.

assert.lengthOf(myReplace, 3);

myReplace("Let us go to the store", "store", "mall") should return the string Let us go to the mall.

assert.deepEqual(
  myReplace('Let us go to the store', 'store', 'mall'),
  'Let us go to the mall'
);

myReplace("He is Sleeping on the couch", "Sleeping", "sitting") should return the string He is Sitting on the couch.

assert.deepEqual(
  myReplace('He is Sleeping on the couch', 'Sleeping', 'sitting'),
  'He is Sitting on the couch'
);

myReplace("I think we should look up there", "up", "Down") should return the string I think we should look down there.

assert.deepEqual(
  myReplace('I think we should look up there', 'up', 'Down'),
  'I think we should look down there'
);

myReplace("This has a spellngi error", "spellngi", "spelling") should return the string This has a spelling error.

assert.deepEqual(
  myReplace('This has a spellngi error', 'spellngi', 'spelling'),
  'This has a spelling error'
);

myReplace("His name is Tom", "Tom", "john") should return the string His name is John.

assert.deepEqual(
  myReplace('His name is Tom', 'Tom', 'john'),
  'His name is John'
);

myReplace("Let us get back to more Coding", "Coding", "algorithms") should return the string Let us get back to more Algorithms.

assert.deepEqual(
  myReplace('Let us get back to more Coding', 'Coding', 'algorithms'),
  'Let us get back to more Algorithms'
);

--seed--

--seed-contents--

--solutions--

function myReplace(str, before, after) {
  if (before.charAt(0) === before.charAt(0).toUpperCase()) {
    after = after.charAt(0).toUpperCase() + after.substring(1);
  } else {
    after = after.charAt(0).toLowerCase() + after.substring(1);
  }
  return str.replace(before, after);
}