pentzzsolt/sass-recursive-map-merge

A lightweight Sass function that merges multidimensional maps recursively.

sass-recursive-map-merge's Issues

Recusively join lists insde maps?

Hi, I was wondering if it was an intentional decision to not recursively join lists which are inside the maps being merged?

Eg:

@import "node_modules/sass-recursive-map-merge/_recursive-map-merge.scss";
$test1: (
	'a': (1,2,3),
);
$test2: (
	'a': (4,5,6),
);
@debug map-merge($test1, $test2);
@debug recursive-map-merge($test1, $test2);

I would expect to get the following from a recursive function:

(
	'a': (1,2,3,4,5,6),
);

But it just behaves the same as map-merge and keeps the second map's value.

I have a patch which will join two lists together if they have the same key, but if this was a deliberate design decision then I'll just fork and make my own function for this.

Wrong merge with empty list

So, sometimes we can have a source map which built with other custom maps. Sometimes some of the them may be an empty.

Data:

$map1: ( 
  x: (), 
  y: (2: 2) 
);

$map2: ( 
  x: (1: 1), 
  y: (3: 3) 
);

// Result
(
  x: (),
  y: (2: 2, 3: 3)
)

// Expected
(
  x: (1: 1),
  y: (2: 2, 3: 3)
);

Solution:

// Add small helper function 
@function convert-empty-list-to-map($source) {
  @if ( type-of($source) == list and length($source) == 0 ) {
    @return map-remove((x:x), x);
  }
  @return $source;
};

// Updated function
@function recursive-map-merge($source1, $source2 ) {
  @if ( type-of($source1) == map or ( type-of($source1) == list and length($source1) == 0) ) and
      ( type-of($source2) == map or ( type-of($source2) == list and length($source2) == 0) ) {
    
    // Check both maps and convert to [map] when empty 
    $map1: convert-empty-list-to-map($source1);
    $map2: convert-empty-list-to-map($source2);

    $result: $map1;

    @each $key, $value in $map2 {
      // Check both childs and convert to map when empty
      $map1-child: convert-empty-list-to-map(map-get($map1, $key));
      $map2-child: convert-empty-list-to-map($value);

      @if ( type-of($map1-child) == map and type-of($map2-child) == map ) {
        $result: map-merge($result, ($key: recursive-map-merge($map1-child, $map2-child)));
      }
      @else {
        $result: map-merge($result, ($key: $value));
      }
    }

    @return $result;
  }
  @else {
    @warn "recursive-map-merge() expects it\'s parameters to be map types!";
    @return null;
  }
}

Introduce linter

Create tests

Trying to merge two lists throws error

Expected behavior is to throw warning and return null.

Warning when using on empty maps

If at least one of the maps given to the function as an argument is empty, the function returns null and throws the warning:

recursive-map-merge() expects it's parameters to be map types!

This is because Sass sees empty maps as lists:

$empty-map: ();
if type-of($empty-map) == map {
	//This code is not executed.
}
if type-of($empty-map) == list {
	//This code is executed.
}

Because the function checks if both arguments are maps, it fails with empty maps.

how do I get a value from a map that's been recursively merged?

Hi,

This looks perfect for my current needs creating a cohesive taxonomy and set of variables to be used within a design system.

I think I have a couple of maps merged successfully -- how do I get the required value from the new map?

Here's the maps so far:

$extra-small: (
  'font-size': 12px,
  'font-weight': 400,
  'line-height': 1.4
);
$small: (
  'font-size': 14px,
  'font-weight': 300,
  'line-height': 1.5
);

$regular: (
  'font-size': 18px,
  'font-weight': 500,
  'line-height': 1.35,
);

$sans: recursive-map-merge(
  $extra-small,
  $small,
  $regular
);

Documentation for v1.1.0