bin: add a flag to list the subsystems

This commit adds the flag --list-subsystems to list all the subsystems that are available for use.

fixes nodejs#66

Author: lholmquist

bin/cmd.js

@@ -14,19 +14,22 @@ const formatTap = require('../lib/format-tap')
 const Validator = require('../lib')
 const Tap = require('../lib/tap')
 const utils = require('../lib/utils')
+const subsystem = require('../lib/rules/subsystem')
 const knownOpts = { help: Boolean
 , version: Boolean
 , 'validate-metadata': Boolean
 , tap: Boolean
 , out: path
 , list: Boolean
+, 'list-subsystems': Boolean
 }
 const shortHand = { h: ['--help']
 , v: ['--version']
 , V: ['--validate-metadata']
 , t: ['--tap']
 , o: ['--out']
 , l: ['--list']
+, ls: ['--list-subsystems']
 }
 
 const parsed = nopt(knownOpts, shortHand)
@@ -84,6 +87,11 @@ function loadPatch(uri, cb) {
 
 const v = new Validator(parsed)
 
+if (parsed['list-subsystems']) {
+  utils.describeSubsystem(subsystem.defaults.subsystems)
+  return
+}
+
 if (parsed.list) {
   const ruleNames = Array.from(v.rules.keys())
   const max = ruleNames.reduce((m, item) => {

bin/usage.txt

@@ -8,6 +8,7 @@ core-validate-commit - Validate the commit message for a particular commit in no
     -V, --validate-metadata       validate PR-URL and reviewers (on by default)
     -t, --tap                     output in tap format
     -l, --list                    list rules and their descriptions
+    -ls --list-subsystems         list the available subsystems
 
   examples:
     Validate a single sha:

lib/utils.js

@@ -45,3 +45,16 @@ exports.describeRule = function describeRule(rule, max = 20) {
     console.log(' %s %s', chalk.red(title), chalk.dim(desc))
   }
 }
+
+exports.describeSubsystem = function describeSubsystem(subsystems, max = 20) {
+  if (subsystems) {
+    for (let sub = 0; sub < subsystems.length; sub++) {
+      console.log('%s %s %s',
+        chalk.green(exports.leftPad(subsystems[sub] || '', max)),
+        chalk.green(exports.leftPad(subsystems[sub+1] || '', max)),
+        chalk.green(exports.leftPad(subsystems[sub+2] || '', max))
+      )
+      sub += 2
+    }
+  }
+}