context-slice of `X` can not be determined based on grid-columns

[bserem]

I took some time to check Susy3 today. On a debian system with Sassc, Susy3.0.1 from npm I am getting some unexpected behavior.

While this works:

$susy: (
  columns: 20px susy-repeat(3, 10px) 20px,
);

html {
  width: susy-span(5 of 5);
}

As does this:

$susy: (
  columns: 1 susy-repeat(3) 1,
);

html {
  width: susy-span(5 of 5);
}

None of these work: columns: 20px susy-repeat(3, 100px) 20px, (example from: http://oddbird.net/susy/docs/a-config.html)

Error:

Error: [susy-normalize-columns] context-slice of `5` can not be determined based on grid-columns `20px 100px 100px 100px 20px`.

columns: 10px susy-repeat(3) 10px,

Error:

Error: [susy-normalize-columns] context-slice of `5` can not be determined based on grid-columns `10px 1 1 1 10px`.

Environment details:

$ sassc -v
sassc: 3.4.2
libsass: 3.4.3
sass2scss: 1.1.0
sass: 3.4

[mirisuzanne]

This is (mostly) the documented behavior (see the last paragraph of the shorthand section). Susy can slice a symmetrical grid (all columns are the same size) without knowing what part of the grid you need. For asymmetrical grids, you have to do the slicing explicitly with the susy-slice function.

You report a successful attempt with an asymmetrical grid (your first example). That would not be proper behaviour, but I can't reproduce your results. I get the same error on the first example that I do on the last ones.

[bserem]

I will need to dive into documentation further then.

What is strange is that this works: columns: 10px susy-repeat(3, 10px) 10px, but those don't: columns: 20px susy-repeat(3, 10px) 20px, columns: 10px susy-repeat(3, 100px) 10px,

[mirisuzanne]

That's not so strange.

• 10px susy-repeat(3, 10px) 10px generates 5 equal-width (10px) columns.
• 20px susy-repeat(3, 10px) 20px generates unequal (20px and 10px) columns.
• 10px susy-repeat(3, 100px) 10px generates unequal (10px and 100px) columns.

It doesn't matter if you use susy-repeat, what matters is the end result. If the columns are all the same size, Susy can slice it without worrying about which slice. If the columns are different sizes, Susy needs to know which columns specifically you want to use.

[bserem]

Got it, shall we close the issue?