Progress on "javascript_koans" for first check-in

koans/AboutApplyingWhatWeHaveLearnt.js

@@ -32,16 +32,32 @@ describe("About Applying What We Have Learnt", function() {
         }
     }
 
-    expect(productsICanEat.length).toBe(FILL_ME_IN);
+    expect(productsICanEat.length).toBe(1);
   });
 
   it("given I'm allergic to nuts and hate mushrooms, it should find a pizza I can eat (functional)", function () {
 
       var productsICanEat = [];
 
       /* solve using filter() & all() / any() */
-
-      expect(productsICanEat.length).toBe(FILL_ME_IN);
+
+      function filterBadIngredients () {
+          //takes variable args, but for this example it only filters for nuts and mushrooms.
+          for (var i = 0; i < products.length; i++) {
+              hasBadIngredient = false;
+              for (var j = 0; j < arguments.length; j++) {
+                  if (arguments[j] === "nuts" && products[i].containsNuts === true) {
+                      hasBadIngredient = true;
+                  } else if (_(products[i]).filter(function (x){ return x === arguments[j]})) {
+                      hasBadIngredient = true;
+                  }
+                  if (!hasBadIngredient) {productsICanEat.push(products[i])}
+              }
+	  }
+
+     hasBadIngredient("nuts", "mushrooms");    
+     expect(productsICanEat.length).toBe(1);
+      }
   });
 
   /*********************************************************************************/
@@ -55,14 +71,17 @@ describe("About Applying What We Have Learnt", function() {
       }
     }
 
-    expect(sum).toBe(FILL_ME_IN);
+    expect(sum).toBe(233168);
   });
 
   it("should add all the natural numbers below 1000 that are multiples of 3 or 5 (functional)", function () {
+    var sum = _(_.range(0, 1000)).chain()
+	  .filter(function (x) {return x % 5 === 0 || x % 3 === 0})
+	  .reduce(function (memo, x) {return memo + x}, 0)
+	  .value()
+    /* try chaining range() and reduce() */
 
-    var sum = FILL_ME_IN;    /* try chaining range() and reduce() */
-
-    expect(233168).toBe(FILL_ME_IN);
+    expect(233168).toBe(sum);
   });
 
   /*********************************************************************************/
@@ -75,24 +94,50 @@ describe("About Applying What We Have Learnt", function() {
         }
     }
 
-    expect(ingredientCount['mushrooms']).toBe(FILL_ME_IN);
+    expect(ingredientCount['mushrooms']).toBe(2);
   });
 
   it("should count the ingredient occurrence (functional)", function () {
-    var ingredientCount = { "{ingredient name}": 0 };
+    var ingredientCount = 
 
     /* chain() together map(), flatten() and reduce() */
-
-    expect(ingredientCount['mushrooms']).toBe(FILL_ME_IN);
+    _(products).chain()
+	  .map(function(name) { 
+		return name.ingredients;})
+	  .flatten()
+	  .reduce(function(ingredientCount, i) {
+		  ingredientCount[i] = (ingredientCount[i] || 0) + 1;
+		  return ingredientCount}, {}).value();
+
+    expect(ingredientCount['mushrooms']).toBe(2);
   });
 
-  /*********************************************************************************/
+/*********************************************************************************/
   /* UNCOMMENT FOR EXTRA CREDIT */
-  /*
+
+/* Extra Credit 1 */  
   it("should find the largest prime factor of a composite number", function () {
-
+    //Should factorize to 2^2x3x13
+	var factorThis = _([156]).chain() 
+	  .reduce(function (factorThis, n) {
+		console.log("Trying to factor " + factorThis[n]);
+	    var d = 2; //divisor for factoring
+		while (factorThis[n] > 1) {
+		  while (factorThis[n]%d===0) {
+		    factorThis.push(d); 
+		    factorThis[n] = factorThis[n] / d;
+			console.log("Factors added: " + factorThis[n] + ", " + d);
+		  }
+	      d = d + 1;
+		}
+	    console.log(factorThis);
+	    return factorThis;
+	  }).value();
+  expect(factorThis[-1]).toBe(13);
   });
 
+
+  /*
   it("should find the largest palindrome made from the product of two 3 digit numbers", function () {
 
   });

koans/AboutArrays.js

@@ -3,16 +3,16 @@ describe("About Arrays", function() {
   //We shall contemplate truth by testing reality, via spec expectations.  
   it("should create arrays", function() {
     var emptyArray = [];
-    expect(typeof(emptyArray)).toBe(FILL_ME_IN); //A mistake? - http:javascript.crockford.com/remedial.html
-    expect(emptyArray.length).toBe(FILL_ME_IN);
+    expect(typeof(emptyArray)).toBe('object'); //A mistake? - http:javascript.crockford.com/remedial.html
+    expect(emptyArray.length).toBe(0);
 
     var multiTypeArray = [0, 1, "two", function () { return 3; }, {value1: 4, value2: 5}, [6, 7]];
-    expect(multiTypeArray[0]).toBe(FILL_ME_IN);
-    expect(multiTypeArray[2]).toBe(FILL_ME_IN);
-    expect(multiTypeArray[3]()).toBe(FILL_ME_IN);
-    expect(multiTypeArray[4].value1).toBe(FILL_ME_IN);
-    expect(multiTypeArray[4]["value2"]).toBe(FILL_ME_IN);
-    expect(multiTypeArray[5][0]).toBe(FILL_ME_IN);
+    expect(multiTypeArray[0]).toBe(0);
+    expect(multiTypeArray[2]).toBe("two");
+    expect(multiTypeArray[3]()).toBe(3);
+    expect(multiTypeArray[4].value1).toBe(4);
+    expect(multiTypeArray[4]["value2"]).toBe(5);
+    expect(multiTypeArray[5][0]).toBe(6);
   });
 
   it("should understand array literals", function () {
@@ -23,36 +23,36 @@ describe("About Arrays", function() {
     expect(array).toEqual([1]);
 
     array[1] = 2;
-    expect(array).toEqual([1, FILL_ME_IN]);
+    expect(array).toEqual([1, 2]);
 
     array.push(3);
-    expect(array).toEqual(FILL_ME_IN);
+      expect(array).toEqual([1,2,3]);
   });
 
   it("should understand array length", function () {
     var fourNumberArray = [1, 2, 3, 4];
 
-    expect(fourNumberArray.length).toBe(FILL_ME_IN);
+    expect(fourNumberArray.length).toBe(4);
     fourNumberArray.push(5, 6);
-    expect(fourNumberArray.length).toBe(FILL_ME_IN);
+    expect(fourNumberArray.length).toBe(6);
 
     var tenEmptyElementArray = new Array(10); 
-    expect(tenEmptyElementArray.length).toBe(FILL_ME_IN);
+    expect(tenEmptyElementArray.length).toBe(10);
 
     tenEmptyElementArray.length = 5;
-    expect(tenEmptyElementArray.length).toBe(FILL_ME_IN);
+    expect(tenEmptyElementArray.length).toBe(5);
   });
 
   it("should slice arrays", function () {
     var array = ["peanut", "butter", "and", "jelly"];
 
-    expect(array.slice(0, 1)).toEqual(FILL_ME_IN);
-    expect(array.slice(0, 2)).toEqual(FILL_ME_IN);
-    expect(array.slice(2, 2)).toEqual(FILL_ME_IN);
-    expect(array.slice(2, 20)).toEqual(FILL_ME_IN);
-    expect(array.slice(3, 0)).toEqual(FILL_ME_IN);
-    expect(array.slice(3, 100)).toEqual(FILL_ME_IN);
-    expect(array.slice(5, 1)).toEqual(FILL_ME_IN);
+      expect(array.slice(0, 1)).toEqual(["peanut"]);
+      expect(array.slice(0, 2)).toEqual(["peanut", "butter"]);
+    expect(array.slice(2, 2)).toEqual([]);
+      expect(array.slice(2, 20)).toEqual(["and", "jelly"]);
+    expect(array.slice(3, 0)).toEqual([]);
+    expect(array.slice(3, 100)).toEqual(["jelly"]);
+    expect(array.slice(5, 1)).toEqual([]);
   });
 
   it("should know array references", function () {
@@ -62,36 +62,36 @@ describe("About Arrays", function() {
       refArray[1] = "changed in function";
     }
     passedByReference(array);
-    expect(array[1]).toBe(FILL_ME_IN);
+    expect(array[1]).toBe("changed in function");
 
     var assignedArray = array;
     assignedArray[5] = "changed in assignedArray";
-    expect(array[5]).toBe(FILL_ME_IN);
+    expect(array[5]).toBe("changed in assignedArray");
 
     var copyOfArray = array.slice();
     copyOfArray[3] = "changed in copyOfArray";
-    expect(array[3]).toBe(FILL_ME_IN);
+      expect(array[3]).toBe("three");
   });
 
   it("should push and pop", function () {
     var array = [1, 2];
     array.push(3);
 
-    expect(array).toEqual(FILL_ME_IN);
+      expect(array).toEqual([1,2,3]);
 
     var poppedValue = array.pop();
-    expect(poppedValue).toBe(FILL_ME_IN);
-    expect(array).toEqual(FILL_ME_IN);
+    expect(poppedValue).toBe(3);
+      expect(array).toEqual([1,2]);
   });
 
   it("should know about shifting arrays", function () {
     var array = [1, 2];
 
     array.unshift(3);
-    expect(array).toEqual(FILL_ME_IN);
+      expect(array).toEqual([3, 1, 2]);
 
     var shiftedValue = array.shift();
-    expect(shiftedValue).toEqual(FILL_ME_IN);
-    expect(array).toEqual(FILL_ME_IN);
+    expect(shiftedValue).toEqual(3);
+      expect(array).toEqual([1,2]);
   });  
 });

koans/AboutExpects.js

@@ -2,20 +2,20 @@ describe("About Expects", function() {
 
   //We shall contemplate truth by testing reality, via spec expectations.  
   it("should expect true", function() {
-    expect(false).toBeTruthy(); //This should be true
+    expect(true).toBeTruthy(); //This should be true
   });
 
   //To understand reality, we must compare our expectations against reality.
   it("should expect equality", function () { 
-	  var expectedValue = FILL_ME_IN;
+	  var expectedValue = 2;
 	  var actualValue = 1 + 1;
 
 	  expect(actualValue === expectedValue).toBeTruthy();
   });  
 
   //Some ways of asserting equality are better than others.
   it("should assert equality a better way", function () { 
-	  var expectedValue = FILL_ME_IN;
+	  var expectedValue = 2;
 	  var actualValue = 1 + 1;
 
   // toEqual() compares using common sense equality.
@@ -24,7 +24,7 @@ describe("About Expects", function() {
 
   //Sometimes you need to be really exact about what you "type".
   it("should assert equality with ===", function () { 
-	  var expectedValue = FILL_ME_IN;
+	  var expectedValue = "2";
 	  var actualValue = (1 + 1).toString();
 
   // toBe() will always use === to compare.
@@ -33,6 +33,6 @@ describe("About Expects", function() {
 
   //Sometimes we will ask you to fill in the values.
   it("should have filled in values", function () {
-	  expect(1 + 1).toEqual(FILL_ME_IN);
+	  expect(1 + 1).toEqual(2);
   });
 });

koans/AboutFunctions.js

@@ -6,7 +6,7 @@ describe("About Functions", function() {
       return a + b;
     }
 
-    expect(add(1, 2)).toBe(FILL_ME_IN);
+    expect(add(1, 2)).toBe(3);
   });
 
   it("should know internal variables override outer variables", function () {
@@ -21,9 +21,9 @@ describe("About Functions", function() {
       return message;
     }
 
-    expect(getMessage()).toBe(FILL_ME_IN);
-    expect(overrideMessage()).toBe(FILL_ME_IN);
-    expect(message).toBe(FILL_ME_IN);
+    expect(getMessage()).toBe("Outer");
+    expect(overrideMessage()).toBe("Inner");
+    expect(message).toBe("Outer");
   });
 
   it("should have lexical scoping", function () {
@@ -35,7 +35,7 @@ describe("About Functions", function() {
       }
       return childfunction();
     }
-    expect(parentfunction()).toBe(FILL_ME_IN);
+    expect(parentfunction()).toBe("local");
   });
 
   it("should use lexical scoping to synthesise functions", function () {
@@ -49,7 +49,7 @@ describe("About Functions", function() {
     var increaseBy3 = makeIncreaseByFunction(3);
     var increaseBy5 = makeIncreaseByFunction(5);
 
-    expect(increaseBy3(10) + increaseBy5(10)).toBe(FILL_ME_IN);
+    expect(increaseBy3(10) + increaseBy5(10)).toBe(28);
   });
 
   it("should allow extra function arguments", function () {
@@ -58,13 +58,13 @@ describe("About Functions", function() {
       return firstArg;
     }
 
-    expect(returnFirstArg("first", "second", "third")).toBe(FILL_ME_IN);
+    expect(returnFirstArg("first", "second", "third")).toBe("first");
 
     function returnSecondArg(firstArg, secondArg) {
       return secondArg;
     }
 
-    expect(returnSecondArg("only give first arg")).toBe(FILL_ME_IN);
+    expect(returnSecondArg("only give first arg")).toBe(undefined);
 
     function returnAllArgs() {
       var argsArray = [];
@@ -74,7 +74,7 @@ describe("About Functions", function() {
       return argsArray.join(",");
     }
 
-    expect(returnAllArgs("first", "second", "third")).toBe(FILL_ME_IN);
+    expect(returnAllArgs("first", "second", "third")).toBe("first,second,third");
   });
 
   it("should pass functions as values", function () {
@@ -88,21 +88,23 @@ describe("About Functions", function() {
     };
 
     var praiseSinger = { givePraise: appendRules };
-    expect(praiseSinger.givePraise("John")).toBe(FILL_ME_IN);
+    expect(praiseSinger.givePraise("John")).toBe("John rules!");
 
     praiseSinger.givePraise = appendDoubleRules;
-    expect(praiseSinger.givePraise("Mary")).toBe(FILL_ME_IN);
+    expect(praiseSinger.givePraise("Mary")).toBe("Mary totally rules!");
 
   });
 
   it("should use function body as a string", function () {
     var add = new Function("a", "b", "return a + b;");
-    expect(add(1, 2)).toBe(FILL_ME_IN);
+    expect(add(1, 2)).toBe(3);
 
     var multiply = function (a, b) {
       //An internal comment
       return a * b;
     };
-    expect(multiply.toString()).toBe(FILL_ME_IN);
-  });    
+    //Wow, tried escaping the multiple lines with \n, had a lot of trouble here.
+    var sourceNoWhitespace = multiply.toString().replace(/\s+/g, ' ');
+    expect(sourceNoWhitespace).toBe("function (a, b) { //An internal comment return a * b; }");
+});
 });