str.replace is not a function

[gracedigital]

Running the example task: grunt.registerTask('minify', ['newer:uglify:all']);
I get the following warning: str.replace is not a function Use --force to continue.

Any suggestions on how to resolve? Not sure if this is a bug in the plugin or not...

Here is my package.json
{
"name": "myradio",
"version": "0.1.0",
"devDependencies": {
"grunt": "~0.4.5",
"grunt-contrib-clean": "^1.0.0",
"grunt-contrib-cssmin": "^1.0.2",
"grunt-contrib-uglify": "~0.5.0",
"grunt-exec": "^1.0.1",
"grunt-newer": "^1.2.0"
}
}

[gracedigital]

Here is the task...

    uglify: {
        options: {
            mangleProperties: false
        },
        dynamic_mappings: {
            // Grunt will search for "**/*.js" under "lib/" when the "uglify" task
            // runs and build the appropriate src-dest file mappings then, so you
            // don't need to update the Gruntfile when files are added or removed.
            files: [{
                force: true,
                expand: true, // Enable dynamic expansion.
                cwd: 'assets/scripts/', // Src matches are relative to this path.
                src: ['**/*.js'], // Actual pattern(s) to match.
                dest: 'assets/scripts/min', // Destination path prefix.
                ext: '.min.js', // Dest filepaths will have this extension.
                extDot: 'first' // Extensions in filenames begin after the first dot
            }, ],
        },
    }

   ....

    grunt.registerTask('default', ['clean', ['newer:uglify:all'], 'cssmin']);

[gracedigital]

Disregard. User error. Needed to remove the brackets for the task ['newer:uglify:all']