jscodeshift example (object literal manipulation)

match-and-replace-object-literal.ts

import type { API, FileInfo } from "jscodeshift";

//
// usage:
//   npx jscodeshift --parser tsx --transform match-and-replace-object-literal.ts <files>
//
// { act: "SELL", prc: 0, dt?: null, ... } => { act: "LOSS", prc: 0, dt?: null, ... }
//

export default function transformer(file: FileInfo, api: API): string {
  const j = api.jscodeshift;
  const $j = j(file.source);

  for (const path of $j.find(j.ObjectExpression).paths()) {
    const act = j(path)
      .find(j.ObjectProperty, { key: { type: "Identifier", name: "act" } })
      .filter(
        p =>
          p.parentPath.parentPath === path &&
          p.value.value.type === "StringLiteral" &&
          p.value.value.value === "SELL"
      );

    const prc = j(path)
      .find(j.ObjectProperty, { key: { type: "Identifier", name: "prc" } })
      .filter(
        p =>
          p.parentPath.parentPath === path &&
          p.value.value.type === "NumericLiteral" &&
          p.value.value.value === 0
      );

    const dt = j(path)
      .find(j.ObjectProperty, { key: { type: "Identifier", name: "dt" } })
      .filter(p => p.parentPath.parentPath === path && p.value.value.type !== "NullLiteral");

    if (act.length === 1 && prc.length === 1 && dt.length === 0) {
      act.replaceWith(j.objectProperty(j.identifier("act"), j.stringLiteral("LOSS")));
    }
  }
  return $j.toSource();
}