Hooks

Where it lives

• hooks/fix-pipes.mjsRunsGitHub ↗
  Read the script

  // src/fix-hook.ts
  import { realpathSync } from "fs";
  import { fileURLToPath } from "url";
  function splitTopLevel(command, operators) {
    const parts = [];
    let current = "";
    let i = 0;
    let single = false;
    let double = false;
    let depth = 0;
    while (i < command.length) {
      const ch = command[i];
      const pair = command.slice(i, i + 2);
      if (!single && ch === "\\") {
        current += command.slice(i, i + 2);
        i += 2;
        continue;
      }
      if (!double && ch === "'") single = !single;
      else if (!single && ch === '"') double = !double;
      if (!single && !double) {
        if (ch === "`") return null;
        if (pair === "$(") depth += 1;
        else if (ch === ")" && depth > 0) depth -= 1;
        if (depth === 0) {
          const op = operators.find(
            (o) => command.startsWith(o, i) && (o !== "|" || pair !== "||" && command[i - 1] !== "|")
          );
          if (op) {
            parts.push(current);
            current = "";
            i += op.length;
            continue;
          }
        }
      }
      current += ch;
      i += 1;
    }
    if (single || double || depth > 0) return null;
    parts.push(current);
    return parts;
  }
  function isTruncatingStage(stage) {
    const trimmed = stage.trim();
    const word = trimmed.split(/\s+/)[0] ?? "";
    if (word === "tail" || word === "head") return !/\s-[a-zA-Z]*f/.test(trimmed);
    if (word === "grep" || word === "rg" || word === "egrep" || word === "fgrep") {
      return !/(?:^|\s)-{1,2}(?:[a-zA-Z]*[qclL][a-zA-Z]*|quiet|count|files-with-matches)\b/.test(
        trimmed
      );
    }
    if (word === "sed") return /(?:^|\s)-n\b/.test(trimmed);
    if (word === "cut") return true;
    return false;
  }
  var TEST_INVOCATION = /\b(?:vitest|jest|mocha|pytest|py\.test|unittest|rspec|phpunit|tox|ctest|cargo\s+(?:nextest\s+run|test)|go\s+test|mix\s+test|rake\s+test|composer\s+test|gradlew?\s+test|mvnw?\s+(?:test|verify)|(?:npm|pnpm|yarn|bun)\s+(?:run\s+)?test\b|make\s+test|swift\s+test|dotnet\s+test|test:)|(?:^|\s)--test\b/;
  function fixCommand(command) {
    if (typeof command !== "string" || command.length > 2e4) return null;
    if (command.includes("<<")) return null;
    const statements = splitTopLevel(command, ["&&", "||", ";", "\n"]);
    if (!statements || statements.length === 0) return null;
    const last = statements[statements.length - 1];
    const stages = splitTopLevel(last, ["|"]);
    if (!stages || stages.length < 2) return null;
    let end = stages.length;
    while (end > 1 && isTruncatingStage(stages[end - 1])) end -= 1;
    if (end === stages.length) return null;
    const kept = stages.slice(0, end);
    if (!TEST_INVOCATION.test(kept.join("|"))) return null;
    const fixedLast = kept.map((s) => s.trim()).join(" | ");
    const head = command.slice(0, command.length - last.length);
    const fixed = `${head}${head.endsWith(" ") || head === "" ? "" : " "}${fixedLast}`;
    return fixed === command ? null : fixed;
  }
  async function main() {
    const chunks = [];
    for await (const chunk of process.stdin) chunks.push(chunk);
    const input = JSON.parse(Buffer.concat(chunks).toString("utf8"));
    if (input.tool_name !== "Bash") return;
    const command = input.tool_input?.command;
    if (typeof command !== "string") return;
    const fixed = fixCommand(command);
    if (fixed === null) return;
    process.stdout.write(
      JSON.stringify({
        hookSpecificOutput: {
          hookEventName: "PreToolUse",
          // Only the command changes. The permission decision is not touched:
          // whatever prompt the user would have seen, they still see, now with
          // the fixed command in it.
          updatedInput: { ...input.tool_input, command: fixed }
        }
      })
    );
  }
  var runDirectly = (() => {
    try {
      return process.argv[1] !== void 0 && realpathSync(process.argv[1]) === fileURLToPath(import.meta.url);
    } catch {
      return false;
    }
  })();
  if (runDirectly) {
    main().catch(() => {
    }).finally(() => process.exit(0));
  }
  export {
    fixCommand
  };
  

Read the script before you install anything that runs on your machine. This is the one part of a plugin that acts without being asked.