allow default value to take callback function(file, data) returning d…

…efault value

.gitignore

@@ -1 +1,2 @@
-node_modules
+node_modules
+/*.log

HISTORY.md

@@ -1,3 +1,7 @@
+0.1.2 - August 30, 2014
+-----------------------
+* allow default value to take callback function(file, data) returning default value
+
 0.1.1 - August 30, 2014
 -----------------------
 * only test type against meta keys that exist

README.md

@@ -61,7 +61,9 @@ metalsmith.use(validate([
 		// pattern defaults to '**/*'
 		metadata: {
 			template: {
-				default: 'default.jade'
+				default: function (file, data) {
+					return file + '.jade';
+				},
 				pattern: function (value) {
 					return value.match(/\.jade$/);
 				}
@@ -71,6 +73,8 @@ metalsmith.use(validate([
 ));
 ```
 
+Notice, both `default` and `pattern` accept callbacks.
+
 ## CLI Usage
 
 All of the same options apply, just add them to the `"plugins"` key in your `metalsmith.json` configuration:

lib/index.js

@@ -69,7 +69,7 @@ function plugin(matchers) {
 						var validator = rule.metadata[key];
 
 						if ('default' in validator && !(key in data)) {
-							return data[key] = validator.default;
+							return data[key] = typeof validator.default === 'function' ? validator.default(data[key]) : validator.default;
 						}
 
 						if ('exists' in validator && validator.exists != key in data) {

package.json

@@ -2,7 +2,7 @@
   "name": "metalsmith-validate",
   "description": "A Metalsmith plugin that allows you to easily validate file metadata, checking existence, type, and regex pattern.",
   "repository": "git://github.com/mikestopcontinues/metalsmith-validate.git",
-  "version": "0.1.1",
+  "version": "0.1.2",
   "author": "Mike Stop Continues <mikestopcontinues@gmail.com>",
   "license": "MIT",
   "main": "lib/index.js",

test/fixtures/default-cb/build/one.md

@@ -0,0 +1,2 @@
+
+one

test/fixtures/default-cb/build/two.md

@@ -0,0 +1,2 @@
+
+one

test/fixtures/default-cb/src/one.md

@@ -0,0 +1,5 @@
+---
+default: specified
+---
+
+one

test/fixtures/default-cb/src/two.md

@@ -0,0 +1,4 @@
+---
+---
+
+one

test/index.js

@@ -43,6 +43,30 @@ describe('metalsmith-validate', function () {
 			});
 	});
 
+	it('should apply value returned by default callback if key unspecified', function (done) {
+		Metalsmith('test/fixtures/default-cb')
+			.use(validate([
+				{
+					metadata: {
+						default: {
+							default: function (file, data) {
+								return 'unspecified';
+							}
+						}
+					}
+				}
+			]))
+			.build(function (err, files) {
+				if (err) {
+					return done(err);
+				}
+
+				assert.equal(files['one.md'].default, 'specified');
+				assert.equal(files['two.md'].default, 'unspecified');
+				done();
+			});
+	});
+
 	it('should fail if exists = true and key unspecified', function (done) {
 		Metalsmith('test/fixtures/exists')
 			.use(validate([