Add option to specify file name suffix (#31)

* Add option to specify cusotm part file name

* Rename 'partLabel' to 'suffix'. Also allow suffix to be a function.

* Depend on individual lodash function instead of the whole lodash library

README.md

@@ -41,6 +41,30 @@ gulp.task('watch', function () {
 - `imports` - A boolean (which defaults to `true`). Determines whether or not the first chunk / "blessed" file `@import`s the others.
 - `cacheBuster` - A boolean (which defaults to `true`). If `imports` is `true`, this will add a random query parameter value to prevent against aggressive caching.
 - `log` - A boolean (which defaults to `false`). Logs a small bit of information about the process.
+- `suffix` - Either a string or a function (which defaults to `"-blessed"`). 
+    - If it is a string then it will be appended to the original file name before the index. E.g.
+    ```javascript
+      	//Assume you have long.css that is to be splitted into 3 parts, following code will 
+      	//produce 3 files: long.css, long-part1.css, long-part2.css    
+      	gulp.src('long.css')
+      	    .pipe(bless{
+      	 		suffix: '-part'
+      	    })
+      	    .pipe(gulp.dest('./'));
+
+    ```
+    - If it is a function then whatever returned by the function is appended to the original file name. The function takes in a 1-based index E.g.
+    ```javascript
+    	//Assume you have long.css that is to be splitted into 3 parts, following code will 
+      	//produce 3 files: long.css, long-functionpart1.css, long-functionpart2.css
+      	gulp.src('long.css')
+      	    .pipe(bless{
+      	 		suffix: function(index) {
+      	 			return "-functionpart" + index;
+      	 		}
+      	    })
+      	    .pipe(gulp.dest('./'));
+    ```
 
 Example:
 

index.js

@@ -1,5 +1,8 @@
 'use strict';
 
+var isString        = require("lodash.isstring");
+var isFunction      = require("lodash.isfunction");
+var isUndefined     = require("lodash.isundefined");
 var through         = require('through2');
 var path            = require('path');
 var bless           = require('bless');
@@ -9,12 +12,28 @@ var applySourcemap  = require('vinyl-sourcemaps-apply');
 
 var File = gutil.File;
 var PluginError = gutil.PluginError;
+var createSuffixFunctionFromString = function(configValue) {
+    var actualSuffix = configValue === undefined? "-blessed" : configValue;
+    return function(index) {
+        return actualSuffix + index;
+    }
+}
+var createSuffixFunction = function(configValue) {
+    if(isString(configValue) || isUndefined(configValue)) {
+        return createSuffixFunctionFromString(configValue);
+    } else if(isFunction(configValue)) {
+        return configValue;
+    } else {
+        throw new TypeError("suffix is neither a string nor function");
+    }
+}
 
 module.exports = function(options){
     var pluginName = 'gulp-bless';
     options = options || {};
     options.imports = options.imports === undefined ? true : options.imports;
     options.cacheBuster = options.cacheBuster === undefined ? true : options.cacheBuster;
+    options.suffix = createSuffixFunction(options.suffix);
 
     return through.obj(function(file, enc, cb) {
         if (file.isNull()) return cb(null, file); // ignore
@@ -81,7 +100,7 @@ module.exports = function(options){
             var outputBasename = path.basename(outputFilePath, outputExtension);
 
             var createBlessedFileName = function(index){
-                return outputBasename + '-blessed' + index + outputExtension;
+                return outputBasename + options.suffix(index) + outputExtension;
             };
 
             var addImports = function(index, contents){

package.json

@@ -7,6 +7,9 @@
   "dependencies": {
     "bless": "^4.0.0",
     "gulp-util": "*",
+    "lodash.isfunction": "^3.0.8",
+    "lodash.isstring": "^4.0.1",
+    "lodash.isundefined": "^3.0.1",
     "merge": "~1.2.0",
     "through2": "~0.5.1",
     "vinyl-sourcemaps-apply": "^0.2.1"

test/main.js

@@ -138,7 +138,112 @@ describe('gulp-bless', function() {
             });
         });
 
+        it('should use custom suffix if suffix option is set to a string', function(done){
+            var suffix = "-part"
+            var stream = bless({
+                suffix: suffix
+            });
+
+            fs.readFile('./test/css/long.css', function(err, data){
+                if(err) throw new Error(err); 
+
+                var longStylesheet = new File({
+                        cwd: "/home/adam/",
+                        base: "/home/adam/test",
+                        path: "/home/adam/test/long-split.css",
+                        contents: new Buffer(data)
+                });
+
+                var actualSplits = []
+                stream.on("data", function(newFile){
+                    actualSplits.push(newFile);
+                });
+
+                stream.on("end", function(){
+                    actualSplits.should.have.length(2);
+                    var masterPart, subPart;
+                    actualSplits.forEach(function(splittedFile){
+                        should.exist(splittedFile);
+                        should.exist(splittedFile.path);
+                        should.exist(splittedFile.relative);
+                        should.exist(splittedFile.contents);
+                        if (path.basename(splittedFile.path) === "long-split.css") {
+                            masterPart = splittedFile;
+                        } else {
+                            subPart = splittedFile;
+                        }
+                    });
+                    should.exist(masterPart);
+                    should.exist(subPart);
+                    path.basename(subPart.path).should.equal("long-split" + suffix + "1.css");
+                    var importRegex = "@import url\\('long-split" + suffix  + "1.css\\?z=[0-9]+'\\);";
+                    masterPart.contents.toString("utf8").should.match(new RegExp(importRegex));
+                    done();
+                });
+
+                stream.write(longStylesheet)  
+                stream.emit("end")             
+            });
+        });
+
+        it('should use custom suffix if suffix option is set to a function', function(done){
+            var suffix = "-functionpart";
+            var stream = bless({
+                suffix: function(index) {
+                    return suffix + "-" + index;
+                }
+            });
+
+            fs.readFile('./test/css/long.css', function(err, data){
+                if(err) throw new Error(err); 
+
+                var longStylesheet = new File({
+                        cwd: "/home/adam/",
+                        base: "/home/adam/test",
+                        path: "/home/adam/test/long-split.css",
+                        contents: new Buffer(data)
+                });
 
+                var actualSplits = []
+                stream.on("data", function(newFile){
+                    actualSplits.push(newFile);
+                });
+
+                stream.on("end", function(){
+                    actualSplits.should.have.length(2);
+                    var masterPart, subPart;
+                    actualSplits.forEach(function(splittedFile){
+                        should.exist(splittedFile);
+                        should.exist(splittedFile.path);
+                        should.exist(splittedFile.relative);
+                        should.exist(splittedFile.contents);
+                        if (path.basename(splittedFile.path) === "long-split.css") {
+                            masterPart = splittedFile;
+                        } else {
+                            subPart = splittedFile;
+                        }
+                    });
+                    should.exist(masterPart);
+                    should.exist(subPart);
+                    path.basename(subPart.path).should.equal("long-split" + suffix + "-1.css");
+                    var importRegex = "@import url\\('long-split" + suffix  + "-1.css\\?z=[0-9]+'\\);";
+                    masterPart.contents.toString("utf8").should.match(new RegExp(importRegex));
+                    done();
+                });
+
+                stream.write(longStylesheet)  
+                stream.emit("end")             
+            });
+        });
+
+        it('should throw error if suffix option is neither string nor function', function(done){ 
+
+            (function callBlessWithInvalidSuffix() {
+                gulp.src('./test/css/long.css')
+                    .pipe(bless({suffix:{}}))
+            }).should.throw(/.*suffix.*string.*function.*/);
+            done();
+        });
 
         it('should apply sourcemaps', function(done){
             var expectedSplits = [