Liberate common validator-formatter test function

This has been modified from the original to use Chai instead of the `assert'
module.

* test/validate/formatter/common.js: Added.

test/validate/formatter/common.js

@@ -0,0 +1,95 @@
+/**
+ * Common validator-formatter test functions
+ *
+ *  Copyright (C) 2016 LoVullo Associates, Inc.
+ *
+ *  This file is part of liza.
+ *
+ *  liza is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+var liza   = require( '../../../' ),
+    VFmt   = liza.validate.ValidatorFormatter,
+    Class  = require( 'easejs' ).Class,
+    expect = require( 'chai' ).expect;
+
+
+module.exports = {
+    testValidate: function( sut, tests )
+    {
+        it( 'is a ValidatorFormatter', function()
+        {
+            expect( Class.isA( VFmt, sut ) )
+                .to.equal( true, 'Is not a ValidatorFormatter' );
+        } );
+
+
+        Object.keys( tests ).forEach( function( data )
+        {
+            var failure  = false,
+                err      = function() { failure = true; },
+                result   = '',
+                fmt      = '',
+                expected = tests[ data ];
+
+            try
+            {
+                result = sut.parse( data );
+            }
+            catch ( e )
+            {
+                failure = true;
+            }
+
+            if ( expected === false )
+            {
+                it( 'fails on ' + data, function()
+                {
+                    expect( failure ).to.equal(
+                        true,
+                        ( data + " should yield error" )
+                    );
+                } );
+
+                return;
+            }
+
+            fmt = sut.retrieve( result );
+
+            var expval = ( ( expected[ 0 ] === true ) ? data : expected[ 0 ] ),
+                retval = ( ( expected[ 1 ] === true )
+                    ? data
+                    : ( expected[ 1 ] === undefined ) ? data : expected[ 1 ]
+                );
+
+            // convert to store in bucket
+            it ( 'parses "' + data + '" as "' + expval + '"', function()
+            {
+                expect( result ).to.equal(
+                    expval,
+                    ( data + " !-> " + expval + ' (=>' + result + ')' )
+                );
+            } );
+
+            // retrieve value, formatted
+            it ( 'retrieves "' + result + '" as "' + retval + '"', function()
+            {
+                expect( fmt ).to.equal(
+                    retval,
+                    ( result + " !~> " + retval + ' (=>' + fmt + ')' )
+                );
+            } );
+        } );
+    }
+};