Scanning for usage of NPM packages

README.md

Run with deno:

deno task deps <path to source dir>

deno.json

{
  "tasks": {
    "deps": "deno run --allow-read ./deps.ts"
  },
  "imports": {
    "std/fs/": "https://deno.land/std@0.207.0/fs/",
    "std/path/": "https://deno.land/std@0.207.0/path/"
  }
}

deps.ts

import { walk } from "std/fs/walk.ts";
import { toFileUrl } from "std/path/mod.ts";

const importMatcher = /^import.*?from\s+['"](.*?)['"];?$/gm;

const sourceMatcher = /\.[tj]sx?$/;

const enumerateFiles = async (
  packageMatch: (name: string) => boolean,
  dir: URL
) => {
  const packages = new Set<string>();
  for await (const entry of walk(dir, {
    includeFiles: true,
    includeDirs: false,
    match: [sourceMatcher],
  })) {
    const file = await Deno.open(entry.path, { read: true });
    const reader = file.readable
      .pipeThrough(new TextDecoderStream())
      .getReader();
    while (true) {
      const { done, value } = await reader.read();
      if (done) break;
      const matches = value.matchAll(importMatcher);
      for (const match of matches) {
        if (packageMatch(match[1])) packages.add(match[1]);
      }
    }
  }

  return packages;
};

const target = new URL(Deno.args[0], toFileUrl(Deno.cwd()) + "/");

const packages = await enumerateFiles(
  (packageName) =>
    !packageName.startsWith(".") && !packageName.startsWith("@blotoutio/"),
  target
);

for (const code of packages) {
  console.log(code.toString());
}