Changed behavior in: std/encoding/csv.ts

[cfjello]

I have observed a changed behavior when using deno 1.18.0 and 'https://deno.land/std/encoding/csv.ts':

I'm am not sure if this is a bug or just some type related fallout.

Steps to reproduce

Here is some working code using [email protected]/encoding/csv.ts:

// import { parse as parseCsv } from 'https://deno.land/std/encoding/csv.ts';

 import {
    parse as parseCsv
  } from 'https://deno.land/[email protected]/encoding/csv.ts'


const content = await parseCsv(await Deno.readTextFile('csvTestItems.csv'), {
  skipFirstRow: true,
  parse: (e: any): unknown => {
    return { item: e.Name, quantity: e.Quantity, pricePerItem: `$${e.Price.toLocaleString('en-US')}`, isExpensive: e.Price >= 3000 };
  },
});

console.log(content);

This compiles and runs without problems:

deno run -A --unstable csvTest.ts

If you switch the import statement to the one at the very top in order use the newer csv.ts version:

import { parse as parseCsv } from 'https://deno.land/std/encoding/csv.ts';

you get the following Typescript error:

Check file:///C:/Work/GHCN-DAILY/csvTest.ts
error: TS2769 [ERROR]: No overload matches this call.
The last overload gave the following error.
Argument of type '{ skipFirstRow: true; parse: (e: any) => unknown; }' is not assignable to parameter of type 'ParseOptions'.
Object literal may only specify known properties, and 'parse' does not exist in type 'ParseOptions'.
parse: (e: any): unknown => {
^
at file:///C:/Work/GHCN-DAILY/csvTest.ts:11:3

TS2771 [ERROR]: The last overload is declared here.
export async function parse(
~~~~~
at https://deno.land/[email protected]/encoding/csv.ts:387:23

[kt3k]

We changed parse behavior at v0.122.0 (PR: #1724)

We change the return type of parse() depending on the given options, and also removed the .parse option (because .parse option can be rewritten as .map(parse) call to the result).

If you don't have time to update the script, please use the pinned version below <= v0.121.0. If you can update the script, please try the script like the below:

import { 
  parse as parseCsv,
} from "https://deno.land/[email protected]/encoding/csv.ts";

const content = (await parseCsv(await Deno.readTextFile("csvTestItems.csv"), { 
  skipFirstRow: true,
})).map((e: any) => { 
  return { item: e.Name, quantity: e.Quantity, pricePerItem: `$${e.Price.toLocaleString("en-US")}`, isExpensive: e.Price >= 3000 };
});

console.log(content);

[cfjello]

I will update - thanks for the quick reply!
One question though: is this documented?

[kt3k]

The informations about breaking changes are available at the release page of each version, for example, https://github.com/denoland/deno_std/releases/tag/0.122.0