Unable to use a variable or value index for object in assign tag

[chippers]

liquid-rust version: 0.16.0
rust version: 1.29.1
OS: Xubuntu 18.04

Hi again, and thanks for such a rapid fix yesterday.

Here, we are unable to use a value as an index to an object in an assign tag. I've updated the small testable case from yesterday as an example.

{% for kv in site.data.authors %}
{% assign name = kv[1].name %}
* {{ kv[0] }}: {{ name }}
{% endfor %}

The failure is in assign, it works when kv[1].name is directly used. (what is the name of the {{ }} blocks?)

This is used quite a lot in arewewebyet, and many Jekyll project's I've written/read make use of this feature to shorthand variables that are otherwise unwieldy. It's possible to not use it, but this feature makes reading the code a lot easier.

I took a quick look at perhaps implementing the fix myself, but after a small bit of reading it seems like the fix would likely be relatively invasive for a codebase I am not familiar with yet. Here's some of the things I found that might help:

• It seems that parsing the assign tag's arguments goes wrong when parsing into a FilterChain
• fn parse_output expects there to only be a single Token of input to turn into an Argument
• The lexer outputs [Identifier("kv"), OpenSquare, IntegerLiteral(1), CloseSquare, Dot, Identifier("name")] for the input kv[1].name
• In the library that Jekyll uses, liquid-c, the parser has a special case for Token::OpenSquare in parse_expression and parse_variable. It also has a special case for Token::Dot, but in liquid-rust the dots are already handled and put inside a single identifier - like Identifier("site.data.authors").

Hopefully some of that is helpful, again not yet familiar with the codebase.

Thanks

[epage]

Yeah, the parser is in terrible shape and gets in the way of conforming (e.g. #92, #145). I'd rather rewrite it (#138) but just haven't gotten to it yet.

I'll take a look to see what I can do.

[epage]

I actually got something to work! Going to bed soon, it'll probably be tomorrow morning before I finish the merges and get the releases out

[epage]

New cobalt release is now out!