ninja.ts

ninja.ts

/*
  Simplest and least ambitious task-orchestration for Node-based projects

  https://ninja-build.org/manual.html
*/

import { spawn } from "child_process";
import { promises as fs } from "fs";
import glob from "glob";
import path from "path";

let output = `
build always: phony
`;

interface RuleDefinition {
  name: string;
  description: string;
  command: string;
  inputs?: string[];
  outputs?: string[];
  cwd?: string;
  always?: boolean;
  console?: boolean;
}

export function rule({
  name,
  description,
  command,
  cwd,
  inputs = [],
  outputs = [],
  always = false,
  console = false,
}: RuleDefinition) {
  const cd = cwd ? `cd ${cwd}` : "true";
  const marker = `.flow-build/${name}.marker`;

  output += `
rule ${name}
  command = ( ${cd} && ( ${command} ) ) && touch $marker
  description = "${description}"

build ${marker} ${outputs.join(" ")}: ${name} ${inputs.join(" ")} ${
    always ? "| always" : ""
  }
  marker = ${marker}
  ${console ? "pool = console" : ""}
`;

  return marker;
}

export function files(pattern: string) {
  return glob.sync(pattern);
}

export function build() {
  fs.writeFile("build.ninja", output);
  spawn("ninja", { stdio: "inherit" });
}