ljharb/qs

Arrays parsed incorrectly

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#288 opened on Nov 27, 2018

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 (3 comments) (3 reactions) (0 assignees)JavaScript (8,015 stars) (744 forks)batch import
feature requesthelp wantedparse

Description

Hi, I have this object:

const filter = {
  3: [{ name: 'Test', id: 50753 }, { name: 'Test2', id: 48464 }],
  6: ['2018-11-01', '2018-11-02']
}

I call stringify and parse

const stringifyQuery = Qs.stringify(filter, { arrayFormat: 'brackets' })
const parseQuery = Qs.parse(stringifyQuery, { arrayLimit: 0 })

Result parse: Key '3' contains only 1 element instead of 2. And this element contains the merged keys name, id:

3: Array(1)
  0:
    id: (2) ["50753", "48464"]
    name: (2) ["Test", "Test2"]

I expect:

3: Array(2)
  0: {name: "Test", id: 50753}
  1: {name: "Test2", id: 48464}

Please help me https://codepen.io/anon/pen/rQrqXx

Contributor guide

Tech stack
javascriptnodejs
Domain
backend
Issue type
bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
3
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-3 hours
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
stale
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
clear
Prerequisites
JavaScriptunderstanding of querystring parsing
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
40
Research direction
Investigate the parsing logic in the qs library, specifically the handling of arrayLimit:0 and arrayFormat:'brackets'. Look at the source code in lib/parse.js to understand how arrays with mixed types (objects and primitives) are parsed. The issue provides a clear reproduction case. Check if there are any existing comments or PRs addressing this. The fix likely requires adjusting the parser to handle arrayLimit:0 correctly when arrayFormat is 'brackets'.