Improper merging of unequal keys in map-merge

[davidkpiano]

TEST:

$map: ();

$map: map-merge($map, (1 2: 3));
$map: map-merge($map, (2 1: 3));

.test {
  test: inspect($map);
}

EXPECTED: (Ruby Sass)

.test {
  test: (1 2: 3, 2 1: 3);
}

ACTUAL: (LibSass 3.2.5)

.test {
  test: (1 2: 3);
}

I'll write specs for all these issues soon, I promise!

[mgreter]

Thxs for the report @davidkpiano! I can confirm this issue and also have a fix ready!

In ast.hpp class List virtual size_t hash():

- hash_ ^= (elements()[i])->hash();
+ hash_ ^= (elements()[i])->hash() + (i + 1);

[mgreter]

First solution approach was too naive, should use this instead:

  template <typename T>
  void hash_combine (std::size_t& seed, const T& val)
  {
    seed ^= std::hash<T>()(val) + 0x9e3779b9
             + (seed<<6) + (seed>>2);
  }
...
      for (size_t i = 0, L = length(); i < L; ++i)
        hash_combine(hash_, (elements()[i])->hash());

[xzyfer]

Specs added sass/sass-spec#414

[okdana]

Thank you for fixing this!

[xzyfer]

This is fixed and will be in 3.3.