v0.4.2

0.4.2

Minor Changes

• ce9db42: Added support for widening in Array.lastIndexOf, Array.indexOf, ReadonlyArray.lastIndexOf and ReadonlyArray.indexOf.

• 107dfc2: Changed the array.includes on readonly arrays to NOT be a type predicate. Before this change, this perfectly valid code would not behave correctly.

  type Code = 0 | 1 | 2;
  type SpecificCode = 0 | 1;
  
  const currentCode: Code = 0;
  
  // Create an empty list of subset type
  const specificCodeList: ReadonlyArray<SpecificCode> = [];
  
  // This will be false, since 0 is not in []
  if (specificCodeList.includes(currentCode)) {
    currentCode; // -> SpecificCode
  } else {
    // This branch will be entered, and ts will think z is 2, when it is actually 0
    currentCode; // -> 2
  }

  Removing the type predicate brings ts-reset closer towards correctness.

• 4765413: author: @mefechoel

  Added the Map.has rule.

  Similar to .includes or Set.has(), Map.has() doesn't let you pass members that don't exist in the map's keys:

  // BEFORE
  const userMap = new Map([
    ["matt", 0],
    ["sofia", 1],
    [2, "waqas"],
  ] as const);
  
  // Argument of type '"bryan"' is not assignable to
  // parameter of type '"matt" | "sofia" | "waqas"'.
  userMap.has("bryan");

  With the rule enabled, Map follows the same semantics as Set.

  // AFTER
  import "@total-typescript/ts-reset/map-has";
  
  const userMap = new Map([
    ["matt", 0],
    ["sofia", 1],
    [2, "waqas"],
  ] as const);
  
  // .has now takes a string as the argument!
  userMap.has("bryan");

Patch Changes

• b15aaa4: Fixed an oversight with the initial set-has implementation by adding support to ReadonlySet.