#!/usr/bin/env -S deno run --allow-all /** * jscpd runner that prints actionable guidance when duplication is found. * * jscpd's own console report tells you *where* the duplication is, but not what * to do about it. This wrapper runs jscpd unchanged and forwards every arg, then * — only on a non-zero exit — appends a loud reminder of the project's * no-new-duplication policy: extract a helper, or curry, and reserve * `jscpd:ignore` for unavoidable boilerplate. The configs skip imports. * * After every scan it also names the worst duplication in the report: the * code that appears in the most places, then the one with the most tokens. * * Usage: deno run -A scripts/cpd.ts */ import { join } from "node:path"; import * as v from "valibot"; import { projectRoot } from "#scripts/project-root.ts"; import { ensureJscpd } from "./jscpd/install.ts"; import { describeWorstFamily, rankCloneFamilies, readClonePairs, } from "./jscpd/worst.ts"; import { bold, red, yellow } from "./precommit/colors.ts"; // `--update` records the current clones into the committed baseline instead // of checking for new ones, so translate it for jscpd and drop the check. const args = Deno.args.includes("--update") ? [ ...Deno.args.filter( (arg) => arg !== "--update" && arg !== "--fail-on-new-clones", ), "--update-baseline", ] : Deno.args; /** The report that this scan writes, read from the config that `--config` * names. Every cpd task passes `--config`. */ const reportPath = async (): Promise<{ config: string; report: string }> => { const config = args[args.indexOf("--config") + 1]; if (!args.includes("--config") || config === undefined) { throw new Error("scripts/cpd.ts needs --config "); } const { output } = v.parse( v.object({ output: v.string() }), JSON.parse(await Deno.readTextFile(config)), ); return { config, report: join(projectRoot, output, "jscpd-report.json") }; }; const { config, report } = await reportPath(); // A crash before jscpd writes its report must not show the last run's report. await Deno.remove(report).catch((error) => { if (!(error instanceof Deno.errors.NotFound)) throw error; }); const { code } = await new Deno.Command(await ensureJscpd(), { args, }).spawn().status; const families = rankCloneFamilies( readClonePairs(JSON.parse(await Deno.readTextFile(report))), ); console.error( yellow(describeWorstFamily(config, families, projectRoot).join("\n")), ); if (code !== 0) { console.error(` ${bold(red("━━━ jscpd: duplicated code found — no new duplication is allowed ━━━"))} Do NOT reach for ${bold("/* jscpd:ignore */")} to silence this. Fix the duplication: ${bold("1. Write a helper.")} This is the answer in ~99.999% of cases. If an obvious shared function jumps out, extract it and call it from both sites. ${bold("2. No obvious helper? Curry.")} Lift the parts that differ into arguments of a function that returns the specialised version, then call it at each site. ${yellow("Then review your work before committing")} — zoom out one step further. The first small curry you reach for is often not the best one; a larger, more holistic curry across the call sites is very frequently far better. ${bold("3. jscpd:ignore is the LAST resort.")} The configs already skip import and re-export statements, so imports never need a marker. Keep a marker for the rare unavoidable scrap of boilerplate/infrastructure we have no control over. Anywhere else an ignore tag is a code smell, not a fix. ${yellow("Never restructure the code just to break the token match")} (a config object, a rename, reordering) while two parallel implementations stay standing. That hides the signal and keeps the duplication. The question is "how do I make these two things one thing", not "how do I make jscpd stop flagging this". `); } Deno.exit(code);