feat(encoding/csv/streaming): Added skipFirstRow and columns options

[ayame113]

close #2559

This PR adds the ability to parse csv with headers to the WebStream based csv parser.

The additional options (skipFirstRow and columns) work exactly the same as when specify them in the existing synchronous csv parser.

how it works

import { parse } from "./csv.ts";
import { CsvStream } from "./csv/stream.ts";
import { readableStreamFromIterable } from "../streams/readable_stream_from_iterable.ts";

const csv = `a,b,c
d,e,f
`;

// It shows how each option works.
const readable1 = readableStreamFromIterable(csv).pipeThrough(new CsvStream({ skipFirstRow: true }));
for await (const data of readable1) {
  console.log(data); // { a: "d", b: "e", c: "f" }
}

const readable2 = readableStreamFromIterable(csv).pipeThrough(new CsvStream({ columns: ["aaa", "bbb", "ccc"] }));
for await (const data of readable2) {
  console.log(data); // { aaa: "a", bbb: "b", ccc: "c" }, { aaa: "d", bbb: "e", ccc: "f" }
}

const readable3 = readableStreamFromIterable(csv).pipeThrough(new CsvStream({ skipFirstRow: true, columns: ["aaa", "bbb", "ccc"] }));
for await (const data of readable3) {
  console.log(data); // { aaa: "d", bbb: "e", ccc: "f" }
}

// The output is the same as the existing synchronous parse function.
console.log(parse(csv, { skipFirstRow: true })); // [ { a: "d", b: "e", c: "f" } ]
console.log(parse(csv, { columns: ["aaa", "bbb", "ccc"] })); // [ { aaa: "a", bbb: "b", ccc: "c" }, { aaa: "d", bbb: "e", ccc: "f" } ]
console.log(parse(csv, { skipFirstRow: true, columns: ["aaa", "bbb", "ccc"] })); // [ { aaa: "d", bbb: "e", ccc: "f" } ]

[ayame113]

These test cases were copied from csv_test.ts.

[ayame113]

I suspect the CI failure is related to the following changes:

• refactor: deno_graph 0.43 upgrade deno#17692
  • One TODO comment resolved by swc upgrade.
  • https://github.com/denoland/deno_std/blob/3e9b8943fdd3a0729f1e34e8668eec56f991c81d/testing/asserts_test.ts#L1298-L1302
• update(ban-types): add BigInt type check deno_lint#1124

[kt3k]

LGTM. Nice feature!