Cassette ExcludeDirectorySearch

ExcludeDirectorySearch.cs

/// <summary>
/// An exclude directory search for Cassette. Provide the patterns you want to search for
/// and this will exclude *.min/*-vsdoc files as well as the directories you specify.
/// </summary>
public class ExcludeDirectorySearch : FileSearch
{
    /// <summary>
    /// Excludes specified directories in search (also .min and -vsdoc files)
    /// </summary>
    /// <param name="pattern">File search pattern (wildcards, e.g. *.css;*.less)</param>
    /// <param name="directoriesToExclude">A string array of folder names to exclude. Will match anywhere in full file path.</param>
    public ExcludeDirectorySearch(string pattern, string[] directoriesToExclude)
    {
	SearchOption = SearchOption.AllDirectories;
	Pattern = pattern;
	ExcludeDirectories = directoriesToExclude;
    }

    private string[] ExcludeDirectories
    {
	set
	{
	    // Join with rx | (or)
	    var directories = String.Join("|", value);

	    // Extensions "*.js;*.coffee" => "js", "coffee"
	    // Assumes you're using wildcard... but whatever.
	    var extensions = String.Join("|", Pattern.Split(new[] { ';', ',' }, StringSplitOptions.RemoveEmptyEntries).
		Select(s => s.Substring(2)).ToArray());

	    var excludeRegex =
		new Regex(String.Format(@"(
		    {0}                  # Directory exclusions
		)[\\/]|([\.-](
		    vsdoc       |        # Vsdoc files                    
		    min                  # Minified files
		)\.({1})$)", directories, extensions), RegexOptions.IgnorePatternWhitespace);

	    // Set exclusions
	    Exclude = excludeRegex;
	}
    }
}

This is very limited in scope; it'll break if directories have special Regex characters and it's probably not efficient (especially if the search is called more than once). TODO is to refactor into a real IFileSearch implementation that intelligently excludes directories and file suffixes.

I needed precisely this kind of IFileSearch implementation, so I basically wrote an augmented variant of the standard FileSearch, including directory exclusion, without having to rely on a single Regex. It isn't very elegant currently (as it duplicates most of the code from FileSearch), but it seems to work decently. If there's a good way to isolate it out and get some code reuse, I'd be glad to hear about it.

Thanks for this. In order to get it to work, I had to add using System.IO; in order to get SearchOption = SearchOption.AllDirectories; to work properly.