Migration script changes Node ts files into Deno ts files

migrate.js

const fs = require("fs");
const path = require("path");

const fileNames = fs.readdirSync(path.resolve(__dirname, "./solutions"));
const testFiles = fileNames.filter(fileName => fileName.endsWith("_test.ts"));

for (const fileName of testFiles) {
// const fileName = testFiles[Math.floor(Math.random() * testFiles.length)];
// const fileName = "search_a2d_matrix2_test.ts";

try {
  const text = fs.readFileSync(
    path.resolve(__dirname, "./solutions", fileName),
    "utf-8"
  );
  const lines = text.split("\n");

  const importLine = lines.findIndex(line =>
    /^import [0-9A-z]+ from "\.\/[0-9A-z]+";$/.test(line)
  );
  const testCaseStart = lines.findIndex(line =>
    /^ *const TEST_CASES = new Map(<.+>)?\(\[/.test(line)
  );
  const testCaseEnd = lines.findIndex(
    (line, index) => index > testCaseStart && line.startsWith("  ]);")
  );
  const testForLoopStart = lines.findIndex(line =>
    line.startsWith("  for (const [")
  );
  const testForLoopEnd = lines.findIndex(
    (line, index) => index > testForLoopStart && line.startsWith("  }")
  );

  if (testCaseStart !== -1) {
    const functionName = /^import ([0-9A-z]+) from "\.\/[0-9A-z]+";$/.exec(
      lines[importLine]
    )[1];
    const testCases = JSON.parse(
      "[" + lines.slice(testCaseStart + 1, testCaseEnd).join("") + "]"
    );
    let isMaybeArrayArgs = false;

    if (testCases.some(([args, _]) => args.includes(null))) {
      isMaybeArrayArgs = true;
    }

    if (testCases.some(([args, _]) => args.some(Array.isArray))) {
      isMaybeArrayArgs = true;
    }

    lines.splice(
      importLine,
      1,
      `import ${functionName} from "./${fileName.replace("_test.ts", ".ts")}";`
    );
    lines.splice(testForLoopStart, testForLoopEnd - testForLoopStart + 1);
    lines.splice(
      testCaseStart,
      testCaseEnd - testCaseStart + 1,
      ...testCases.map(([args, expected]) =>
        isMaybeArrayArgs
          ? `  assertEquals(${functionName}(${JSON.stringify(
              args
            )}), ${JSON.stringify(expected)});`
          : `  assert(${functionName}(${JSON.stringify(
              args
            )}) === ${JSON.stringify(expected)});`
      )
    );

    console.log("OK", fileName);
    //   console.log(isMaybeArrayArgs);
    // console.log(lines.join("\n"));

    fs.writeFileSync(
      path.resolve(__dirname, "./solutions", fileName),
      lines.join("\n"),
      { encoding: "utf8", flag: "w" }
    );

    // break;
  } else {
    console.log("SKIP", fileName);
  }
} catch (error) {
  console.log("ERROR", fileName);
  console.log(error);
}
}