prop function nesting

kemsky · Oct 22, 2015 · 89f25aa · 89f25aa
1 parent faa0825
commit 89f25aa
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Showing 7 changed files with 156 additions and 29 deletions.
diff --git a/README.md b/README.md
@@ -108,7 +108,8 @@ var result:Stream = s.filter(function(item:Item):Boolean{
 });
 
 // 2. using provided global functions(can compare Boolean, Number, Date, XML, String types)
-var result:Stream = s.filter(gt(prop(_, "price"), 1));
+//    supports nested properties i.e. prop("prop.prop.prop")
+var result:Stream = s.filter(gt(prop("price"), 1));
 
 // 3. using Proxy magick and global functions
 var result:Stream = s.price(gt(_, 1)); 

diff --git a/src/com/kemsky/filters/prop.as b/src/com/kemsky/filters/prop.as
@@ -1,19 +1,73 @@
 package com.kemsky.filters
 {
-    import com.kemsky.support.toValue;
-
     /**
      * Creates function that extracts named property from value
-     * @param value item or function applied to item
      * @param name name of the property
      * @return function function that extracts named property from value
      */
-    public function prop(value:*, name:String):Function
+    public function prop(name:String):Function
     {
-        return function (item:*):*
+        var path:Array = name.split(".");
+
+        var p1:String = path.length > 0 ? path[0]: undefined;
+        var p2:String = path.length > 1 ? path[1]: undefined;
+        var p3:String = path.length > 2 ? path[2]: undefined;
+        var p4:String = path.length > 3 ? path[3]: undefined;
+        var p5:String = path.length > 4 ? path[4]: undefined;
+
+        switch (path.length)
         {
-            item = toValue(item, value);
-            return item.hasOwnProperty(name) ? item[name] : undefined;
-        };
+            case 1:
+                return function (item:*):*
+                {
+                    return item.hasOwnProperty(p1) ? item[p1] : undefined;
+                };
+            case 2:
+                return function (item:*):*
+                {
+                    var result:* = undefined;
+                    try
+                    {
+                        result = item[p1][p2];
+                    }
+                    catch(e:Error){}
+                    return result;
+                };
+            case 3:
+                return function (item:*):*
+                {
+                    var result:* = undefined;
+                    try
+                    {
+                        result = item[p1][p2][p3];
+                    }
+                    catch(e:Error){}
+                    return result;
+                };
+            case 4:
+                return function (item:*):*
+                {
+                    var result:* = undefined;
+                    try
+                    {
+                        result = item[p1][p2][p3][p4];
+                    }
+                    catch(e:Error){}
+                    return result;
+                };
+            case 5:
+                return function (item:*):*
+                {
+                    var result:* = undefined;
+                    try
+                    {
+                        result = item[p1][p2][p3][p4][p5];
+                    }
+                    catch(e:Error){}
+                    return result;
+                };
+        }
+
+        throw new Error("Property is too deep: '" + name + "', maximum nesting is 5");
     }
 }
diff --git a/src/com/kemsky/support/toValue.as b/src/com/kemsky/support/toValue.as
@@ -11,7 +11,7 @@ package com.kemsky.support
         {
             result = value(item);
         }
-        else if(value !== undefined)
+        else
         {
             result = value;
         }

diff --git a/testSrc/Item.as b/testSrc/Item.as
@@ -7,6 +7,7 @@ package
         public var price:Number;
         public var vat:Number;
         public var bool:Boolean;
+        public var item:Item;
 
         public function Item(name:String = null, price:Number = 0, vat:Number = 0)
         {

diff --git a/testSrc/com/kemsky/TestStream.as b/testSrc/com/kemsky/TestStream.as
@@ -45,13 +45,13 @@ package com.kemsky
 
             var s1:Stream = $(1, 2, 3);
             var i1:StreamIterator = new ValueIterator(s1);
-            var count:int = 0;
+            var count1:int = 0;
             for each (var item:* in i1)
             {
 //                Print.items("for each: ", i1.current, item);
-                if (++count < 10)
+                if (++count1 < 10)
                 {
-                    i1.push(count);
+                    i1.push(count1);
                 }
             }
 
@@ -167,7 +167,7 @@ package com.kemsky
         {
             var item:Item = new Item("name1", 5, 0);
             var s:Stream = $(item);
-            assertEquals(s.map(prop(_, "name")).first, "name1");
+            assertEquals(s.map(prop("name")).first, "name1");
         }
 
         [Test]
@@ -463,6 +463,18 @@ package com.kemsky
             });
 
             assertEquals(sum3, 10);
+
+            try
+            {
+                $().foldLeft(function (prev:Number, current:Number):Number
+                {
+                    return prev + current;
+                });
+                assertTrue(false);
+            }
+            catch(e:Error)
+            {
+            }
         }
 
         [Test]
@@ -488,6 +500,18 @@ package com.kemsky
             });
 
             assertEquals(sum3, 10);
+
+            try
+            {
+                $().foldRight(function (prev:Number, current:Number):Number
+                {
+                    return prev + current;
+                });
+                assertTrue(false);
+            }
+            catch(e:Error)
+            {
+            }
         }
 
         [Test]

diff --git a/testSrc/com/kemsky/filters/TestFilters.as b/testSrc/com/kemsky/filters/TestFilters.as
@@ -7,6 +7,7 @@ package com.kemsky.filters
 
     import org.flexunit.asserts.assertEquals;
     import org.flexunit.asserts.assertFalse;
+    import org.flexunit.asserts.assertTrue;
 
     public class TestFilters
     {
@@ -64,8 +65,8 @@ package com.kemsky.filters
 
             var s:Stream = $(item1, item2);
 
-            assertEquals(s.filter(eq(prop(_, "bool"), true)).first, item2);
-            assertEquals(s.filter(eq(prop(_, "bool"), false)).first, item1);
+            assertEquals(s.filter(eq(prop("bool"), true)).first, item2);
+            assertEquals(s.filter(eq(prop("bool"), false)).first, item1);
         }
 
         [Test]
@@ -155,7 +156,7 @@ package com.kemsky.filters
 
             var s:Stream = $(item1, item2);
 
-            var result:Stream = s.filter(gt(prop(_, "price"), 1));
+            var result:Stream = s.filter(gt(prop("price"), 1));
             assertEquals(result.length, 1);
             assertEquals(result.first, item2);
 
@@ -167,27 +168,73 @@ package com.kemsky.filters
             assertEquals(result.length, 1);
             assertEquals(result.first, item2.price);
 
-            result = s.filter(ge(prop(_, "price"), 2));
+            result = s.filter(ge(prop("price"), 2));
             assertEquals(result.length, 1);
             assertEquals(result.first, item2);
 
-            result = s.filter(gt(add(prop(_, "price"), prop(_, "vat"), 0), 2));
+            result = s.filter(gt(add(prop("price"), prop("vat"), 0), 2));
             assertEquals(result.length, 1);
             assertEquals(result.first, item1);
 
-            result = s.filter(gt(subtract(prop(_, "price"), prop(_, "vat")), 0));
+            result = s.filter(gt(subtract(prop("price"), prop("vat")), 0));
             assertEquals(result.length, 1);
             assertEquals(result.first, item2);
 
-            result = s.filter(gt(subtract(prop(_, "price"), 1), 0));
+            result = s.filter(gt(subtract(prop("price"), 1), 0));
             assertEquals(result.length, 1);
             assertEquals(result.first, item2);
 
             result = s.filter(gt(0, 1));
             assertEquals(result.length, 0);
 
-            result = s.filter(ge(prop(prop(_, "name"), "length"), 1));
-            assertEquals(result.length, 2);
+            var obj:Item = new Item("p0");
+            obj.item = new Item("p1");
+            obj.item.item = new Item("p2");
+            obj.item.item.item = new Item("p3");
+            obj.item.item.item.item = new Item("p4");
+
+            var nested:Stream = $(obj);
+
+            result = nested.filter(eq(prop("name"), "p0"));
+            assertEquals(result.length, 1);
+
+            result = nested.filter(eq(prop("name1"), undefined));
+            assertEquals(result.length, 1);
+
+
+            result = nested.filter(eq(prop("item.name"), "p1"));
+            assertEquals(result.length, 1);
+
+            result = nested.filter(eq(prop("item.name1"), undefined));
+            assertEquals(result.length, 1);
+
+
+            result = nested.filter(eq(prop("item.item.name"), "p2"));
+            assertEquals(result.length, 1);
+
+            result = nested.filter(eq(prop("item.item.name1"), undefined));
+            assertEquals(result.length, 1);
+
+
+            result = nested.filter(eq(prop("item.item.item.name"), "p3"));
+            assertEquals(result.length, 1);
+
+            result = nested.filter(eq(prop("item.item.item.name1"), undefined));
+            assertEquals(result.length, 1);
+
+
+            result = nested.filter(eq(prop("item.item.item.item.name"), "p4"));
+            assertEquals(result.length, 1);
+
+            result = nested.filter(eq(prop("item.item.item.item.name1"), undefined));
+            assertEquals(result.length, 1);
+
+            try
+            {
+                nested.filter(eq(prop("item.item.item.item.item.name"), "p5"));
+                assertTrue(false);
+            }
+            catch(e:Error){}
 
             //some fun
             result = s.filter(ge(function (item:Item):Number
@@ -221,8 +268,8 @@ package com.kemsky.filters
 
             var s:Stream = $(item);
 
-            assertEquals(s.filter(mapped(prop(_, "name"), d)).length, 1);
-            assertEquals(s.filter(mapped(prop(_, "name"), o)).length, 1);
+            assertEquals(s.filter(mapped(prop("name"), d)).length, 1);
+            assertEquals(s.filter(mapped(prop("name"), o)).length, 1);
 
 
             var p:Stream = $("name", "price", "vat");

diff --git a/testSrc/com/kemsky/support/TestSupport.as b/testSrc/com/kemsky/support/TestSupport.as
@@ -65,10 +65,10 @@ package com.kemsky.support
             assertTrue(toValue(undefined, undefined) === undefined);
 
 
-            assertEquals(toValue(1, undefined), 1);
-            assertEquals(toValue("test", undefined), "test");
-            assertEquals(toValue(date, undefined), date);
-            assertEquals(toValue(null, undefined), null);
+            assertTrue(toValue(1, undefined) === undefined);
+            assertTrue(toValue("test", undefined) === undefined);
+            assertTrue(toValue(date, undefined) === undefined);
+            assertTrue(toValue(null, undefined) === undefined);
 
             var f:Function = function(value:*):*
             {