From 27e23cce9c51892ca62197a423eebdbc1744a621 Mon Sep 17 00:00:00 2001
From: Tim Schaub <tim.schaub@gmail.com>
Date: Sun, 7 Apr 2013 17:37:31 -0600
Subject: [PATCH] Convenient factories for logical filters

---
 src/ol/filter/logicalfilter.js            | 37 ++++++++++++++++++
 test/spec/ol/filter/logicalfilter.test.js | 47 +++++++++++++++++++++++
 2 files changed, 84 insertions(+)

diff --git a/src/ol/filter/logicalfilter.js b/src/ol/filter/logicalfilter.js
index cd5cc66d9e..3ba8dd932c 100644
--- a/src/ol/filter/logicalfilter.js
+++ b/src/ol/filter/logicalfilter.js
@@ -1,5 +1,8 @@
 goog.provide('ol.filter.Logical');
 goog.provide('ol.filter.LogicalOperator');
+goog.provide('ol.filter.and');
+goog.provide('ol.filter.not');
+goog.provide('ol.filter.or');
 
 goog.require('goog.asserts');
 goog.require('ol.filter.Filter');
@@ -79,3 +82,37 @@ ol.filter.LogicalOperator = {
   OR: '||',
   NOT: '!'
 };
+
+
+/**
+ * Create a filter that evaluates to true if any of the provided filters
+ * evaluate to true.
+ * @param {...ol.filter.Filter} var_filters Filters.
+ * @return {ol.filter.Logical} A logical filter.
+ */
+ol.filter.and = function(var_filters) {
+  var filters = Array.prototype.slice.call(arguments);
+  return new ol.filter.Logical(filters, ol.filter.LogicalOperator.AND);
+};
+
+
+/**
+ * Create a new filter that is the logical compliment of another.
+ * @param {ol.filter.Filter} filter The filter to negate.
+ * @return {ol.filter.Logical} A logical filter.
+ */
+ol.filter.not = function(filter) {
+  return new ol.filter.Logical([filter], ol.filter.LogicalOperator.NOT);
+};
+
+
+/**
+ * Create a filter that evaluates to true if all of the provided filters
+ * evaluate to true.
+ * @param {...ol.filter.Filter} var_filters Filters.
+ * @return {ol.filter.Logical} A logical filter.
+ */
+ol.filter.or = function(var_filters) {
+  var filters = Array.prototype.slice.call(arguments);
+  return new ol.filter.Logical(filters, ol.filter.LogicalOperator.OR);
+};
diff --git a/test/spec/ol/filter/logicalfilter.test.js b/test/spec/ol/filter/logicalfilter.test.js
index 61eadbb1ee..970c0d0c10 100644
--- a/test/spec/ol/filter/logicalfilter.test.js
+++ b/test/spec/ol/filter/logicalfilter.test.js
@@ -91,7 +91,54 @@ describe('ol.filter.Logical', function() {
 
 });
 
+describe('ol.filter.and', function() {
+  it('creates the a logical AND filter', function() {
+    var a = new ol.filter.Filter();
+    var b = new ol.filter.Filter();
+    var c = new ol.filter.Filter();
+    var and = ol.filter.and(a, b, c);
+    expect(and).to.be.a(ol.filter.Logical);
+    expect(and.operator).to.be(ol.filter.LogicalOperator.AND);
+    var filters = and.getFilters();
+    expect(filters[0]).to.be(a);
+    expect(filters[1]).to.be(b);
+    expect(filters[2]).to.be(c);
+  });
+});
+
+describe('ol.filter.not', function() {
+  it('creates the logical compliment of another filter', function() {
+    var include = new ol.filter.Filter(function() {return true;});
+    var notInclude = ol.filter.not(include);
+    expect(notInclude).to.be.a(ol.filter.Logical);
+    expect(notInclude.applies()).to.be(false);
+
+    var exclude = new ol.filter.Filter(function() {return false;});
+    var notExclude = ol.filter.not(exclude);
+    expect(notExclude).to.be.a(ol.filter.Logical);
+    expect(notExclude.applies()).to.be(true);
+  });
+});
+
+describe('ol.filter.or', function() {
+  it('creates the a logical OR filter', function() {
+    var a = new ol.filter.Filter();
+    var b = new ol.filter.Filter();
+    var c = new ol.filter.Filter();
+    var and = ol.filter.or(a, b, c);
+    expect(and).to.be.a(ol.filter.Logical);
+    expect(and.operator).to.be(ol.filter.LogicalOperator.OR);
+    var filters = and.getFilters();
+    expect(filters[0]).to.be(a);
+    expect(filters[1]).to.be(b);
+    expect(filters[2]).to.be(c);
+  });
+});
+
 goog.require('ol.Feature');
 goog.require('ol.filter.Filter');
 goog.require('ol.filter.Logical');
 goog.require('ol.filter.LogicalOperator');
+goog.require('ol.filter.and');
+goog.require('ol.filter.not');
+goog.require('ol.filter.or');