feat: add conflicts and implies shorthands. (#753)

README.md

@@ -1382,7 +1382,7 @@ var yargs = require("yargs")(['--help'])
 
 Later on, `argv` can be retrieved with `yargs.argv`.
 
-.implies(x, y)
+<a name="implies"></a>.implies(x, y)
 --------------
 
 Given the key `x` is set, it is required that the key `y` is set.
@@ -1578,13 +1578,15 @@ Valid `opt` keys include:
 - `coerce`: function, coerce or transform parsed command line values into another value, see [`coerce()`](#coerce)
 - `config`: boolean, interpret option as a path to a JSON config file, see [`config()`](#config)
 - `configParser`: function, provide a custom config parsing function, see [`config()`](#config)
+- `conflicts`: string or object, require certain keys not to be set, see [`conflicts()`](#conflicts)
 - `count`: boolean, interpret option as a count of boolean flags, see [`count()`](#count)
 - `default`: value, set a default value for the option, see [`default()`](#default)
 - `defaultDescription`: string, use this description for the default value in help content, see [`default()`](#default)
 - `demandOption`: boolean or string, demand the option be given, with optional error message, see [`demandOption()`](#demandOption)
 - `desc`/`describe`/`description`: string, the option description for help content, see [`describe()`](#describe)
 - `global`: boolean, indicate that this key should not be [reset](#reset) when a command is invoked, see [`global()`](#global)
 - `group`: string, when displaying usage instructions place the option under an alternative group heading, see [`group()`](#group)
+- `implies`: string or object, require certain keys to be set, see [`implies()`](#implies)
 - `nargs`: number, specify how many arguments should be consumed for the option, see [`nargs()`](#nargs)
 - `normalize`: boolean, apply `path.normalize()` to the option, see [`normalize()`](#normalize)
 - `number`: boolean, interpret option as a number, [`number()`](#number)

test/validation.js

@@ -124,6 +124,18 @@ describe('validation tests', function () {
       expect(argv.noFoo).to.not.exist
       expect(argv.foo).to.not.exist
     })
+
+    it('allows key to be specified with option shorthand', function (done) {
+      yargs('--bar')
+        .option('bar', {
+          implies: 'foo'
+        })
+        .fail(function (msg) {
+          msg.should.match(/Implications failed/)
+          return done()
+        })
+        .argv
+    })
   })
 
   describe('conflicts', function () {
@@ -172,6 +184,18 @@ describe('validation tests', function () {
         })
         .argv
     })
+
+    it('allows key to be specified with option shorthand', function (done) {
+      yargs(['-f', '-b'])
+          .option('f', {
+            conflicts: 'b'
+          })
+          .fail(function (msg) {
+            msg.should.equal('Arguments f and b are mutually exclusive')
+            return done()
+          })
+          .argv
+    })
   })
 
   describe('demand', function () {

yargs.js

@@ -535,10 +535,18 @@ function Yargs (processArgs, cwd, parentRequire) {
         self.config(key, opt.configParser)
       }
 
+      if ('conflicts' in opt) {
+        self.conflicts(key, opt.conflicts)
+      }
+
       if ('default' in opt) {
         self.default(key, opt.default)
       }
 
+      if ('implies' in opt) {
+        self.implies(key, opt.implies)
+      }
+
       if ('nargs' in opt) {
         self.nargs(key, opt.nargs)
       }