jsTruthy with blank string returns true

[amit777]

env: "liquidjs": "^9.28.0",

I feel like this use to work but it has been a lot of time since I checked.

const { Liquid, Tokenizer } = require('liquidjs');
const liquid = new Liquid({jsTruthy: true});

let tpl = `{% if blank %} BLANK TRUE {% else %} BLANK FALSE {% endif %}`;
let context = {blank: ''};
(async function() {
 let ret = await liquid.parseAndRender(tpl, context);
 console.log(ret);
 // OUTPUT: BLANK TRUE
})()

[amit777]

Further investigation. The problem seems to be in the following function:

function isFalsy(val, ctx) {
    if (ctx.opts.jsTruthy) {
      console.log(`JSTRUTHY typeof=${typeof val},val=${JSON.stringify(val)}`);
     //OUTPUT:   JSTRUTHY typeof=object,val={}
        return !val;
    }
    else {
        return val === false || undefined === val || val === null;
    }
}

When the string is blank, typeof val is an empty object rather than an empty string. So !val evaluates to false.

[amit777]

Ok... I think i found the problem. The word "blank" as a variable doesn't seem to be valid. It's considered a literalValue. So my test is bad.. if i change blank to blankvar, then it works fine.

[harttle]

Checked Shopify/liquid, blank also always evaluates to "" event it's set to other values in scope. So I guess it's intentional.