@thi.ng/args/usage.js

Declarative, functional & typechecked CLI argument/options parser, value coercions etc.

import { isPlainObject } from "@thi.ng/checks/is-plain-object";
import { lengthAnsi } from "@thi.ng/strings/ansi";
import { capitalize, kebab } from "@thi.ng/strings/case";
import { padRight } from "@thi.ng/strings/pad-right";
import { repeat } from "@thi.ng/strings/repeat";
import { stringify } from "@thi.ng/strings/stringify";
import { SPLIT_ANSI, wordWrapLines } from "@thi.ng/strings/word-wrap";
import {
  DEFAULT_THEME
} from "./api.js";
const usage = (specs, opts = {}) => {
  opts = {
    lineWidth: 80,
    paramWidth: 32,
    showDefaults: true,
    prefix: "",
    suffix: "",
    groups: ["flags", "main"],
    ...opts
  };
  const theme = isPlainObject(opts.color) ? { ...DEFAULT_THEME, ...opts.color } : opts.color ? DEFAULT_THEME : {};
  const indent = repeat(" ", opts.paramWidth);
  const format = (ids) => ids.map((id) => __argUsage(id, specs[id], opts, theme, indent));
  const sortedIDs = Object.keys(specs).sort();
  const groups = opts.groups ? opts.groups.map(
    (gid) => [
      gid,
      sortedIDs.filter((id) => specs[id].group === gid)
    ]
  ).filter((g) => !!g[1].length) : [["options", sortedIDs]];
  return [
    ...__wrap(opts.prefix, opts.lineWidth),
    ...groups.map(
      ([gid, ids]) => [
        ...opts.showGroupNames ? [`${capitalize(gid)}:
`] : [],
        ...format(ids),
        ""
      ].join("\n")
    ),
    ...__wrap(opts.suffix, opts.lineWidth)
  ].join("\n");
};
const __argUsage = (id, spec, opts, theme, indent) => {
  const hint = __argHint(spec, theme);
  const alias = __argAlias(spec, theme, hint);
  const name = __ansi(`--${kebab(id)}`, theme.param);
  const params = `${alias}${name}${hint}`;
  const isRequired = spec.optional === false && spec.default === void 0;
  const prefixes = [];
  isRequired && prefixes.push("required");
  spec.multi && prefixes.push("multiple");
  const body = __argPrefix(prefixes, theme, isRequired) + (spec.desc || "") + __argDefault(spec, opts, theme);
  return padRight(opts.paramWidth)(params, lengthAnsi(params)) + __wrap(body, opts.lineWidth - opts.paramWidth).map((l, i) => i > 0 ? indent + l : l).join("\n");
};
const __argHint = (spec, theme) => spec.hint ? __ansi(" " + spec.hint, theme.hint) : "";
const __argAlias = (spec, theme, hint) => spec.alias ? `${__ansi("-" + spec.alias, theme.param)}${hint}, ` : "";
const __argPrefix = (prefixes, theme, isRequired) => prefixes.length ? __ansi(
  `[${prefixes.join(", ")}] `,
  isRequired ? theme.required : theme.multi
) : "";
const __argDefault = (spec, opts, theme) => opts.showDefaults && spec.default != null && spec.default !== false ? __ansi(
  ` (default: ${stringify(true)(
    spec.defaultHint != void 0 ? spec.defaultHint : spec.default
  )})`,
  theme.default
) : "";
const __ansi = (x, col) => col != null ? `\x1B[${col}m${x}\x1B[0m` : x;
const __wrap = (str, width) => str ? wordWrapLines(str, {
  width,
  splitter: SPLIT_ANSI,
  hard: false
}) : [];
export {
  usage
};