Manchester | 26-ITP-Jan | Abdu Hassen | Sprint 2| Data-Grouping

Sprint-2/debug/address.js

@@ -1,4 +1,4 @@
-// Predict and explain first...
+//Predict and explain first...
 
 // This code should log out the houseNumber from the address object
 // but it isn't working...
@@ -12,4 +12,8 @@ const address = {
   postcode: "XYZ 123",
 };
 
-console.log(`My house number is ${address[0]}`);
+console.log(`My house number is ${address.houseNumber}`);
+
+/* The code constructed well and the code is an object which is it is consist of key and value pair 
+in line 15 inside the console it is return in array method which is the code is not array so we have to change that
+to object call "object.houseNumber" in this way it will work correctly */

Sprint-2/debug/author.js

@@ -11,6 +11,10 @@ const author = {
   alive: true,
 };
 
-for (const value of author) {
-  console.log(value);
+for (const prop in author) {
+  console.log(`${prop}:${author[prop]}`);
 }
+
+/*In this code the problem is that the method for...of is used for array 
+not for object type instead we use for...in this will work through the object
+ and list the key and for value We use author[property] */

Sprint-2/debug/recipe.js

@@ -9,7 +9,10 @@ const recipe = {
   serves: 2,
   ingredients: ["olive oil", "tomatoes", "salt", "pepper"],
 };
+console.log(`${recipe.title} serves ${recipe.serves} 
+ingredients: 
+${recipe.ingredients.join("\n")}`);
 
-console.log(`${recipe.title} serves ${recipe.serves}
-  ingredients:
-${recipe}`);
+/* In this code will log the recipe.title and recipe.serves but recipe.ingredient is not 
+represented well so it can't log the array ,to access and to get all the array index i used  
+for...of loop to log all the ingredient in the array*/

Sprint-2/implement/contains.js

@@ -1,3 +1,11 @@
-function contains() {}
-
+function contains(targetObject, searchTerm) {
+  if (
+    typeof targetObject !== "object" ||
+    targetObject === null ||
+    Array.isArray(targetObject)
+  ) {
+    return false;
+  }
+  return Object.hasOwn(targetObject, searchTerm);
+}
 module.exports = contains;

Sprint-2/implement/contains.test.js

@@ -20,16 +20,37 @@ as the object doesn't contains a key of 'c'
 // Given an empty object
 // When passed to contains
 // Then it should return false
-test.todo("contains on empty object returns false");
+test("The function should return undefined when an empty object is passed to it.", () => {
+  expect(contains({})).toBe(false);
+});
 
 // Given an object with properties
 // When passed to contains with an existing property name
 // Then it should return true
+test("The function should return true when the object contains the targeted property", () => {
+  expect(contains({ town: "leeds" }, "town")).toBe(true);
+  expect(contains({ a: 1, b: 2, c: 3 }, "a")).toBe(true);
+  expect(contains({ name: "ahmed", sex: "male", age: 29 }, "sex")).toBe(true);
+  expect(contains({ zone: 2, zone: 3, zone: 4 }, "zone")).toBe(true);
+});
 
 // Given an object with properties
 // When passed to contains with a non-existent property name
 // Then it should return false
+test("the function should return false when the targeted property don't exist", () => {
+  expect(contains({ a: 1, b: 2, c: 3 }, "d")).toBe(false);
+  expect(contains({ year: 1998, month: 10, Date: 16 }, "age")).toBe(false);
+  expect(contains({ meal: "pizza", drink: "water", table: 3 }, "starter")).toBe(
+    false
+  );
+});
 
 // Given invalid parameters like an array
 // When passed to contains
 // Then it should return false or throw an error
+test("the function should return false when invalid parameter like an array is passed", () => {
+  expect(contains([10, 23, 34, 45], "3")).toBe(false);
+  expect(contains("hello", "hi")).toBe(false);
+  expect(contains(["green", "yellow", "rad"], "0")).toBe(false);
+  expect(contains(((30, 40, 50), 30))).toBe(false);
+});

Sprint-2/implement/lookup.js

@@ -1,5 +1,12 @@
-function createLookup() {
+function createLookup(arrayOfArrays) {
   // implementation here
+  const lookUpObject = {};
+  for (const innerArray of arrayOfArrays) {
+    keyPair = innerArray[0];
+    valuePair = innerArray[1];
+    lookUpObject[keyPair] = valuePair;
+  }
+  return lookUpObject;
 }
 
 module.exports = createLookup;

Sprint-2/implement/lookup.test.js

@@ -1,6 +1,32 @@
 const createLookup = require("./lookup.js");
 
-test.todo("creates a country currency code lookup for multiple codes");
+test("creates a country currency code lookup for multiple codes", () => {
+  expect(
+    createLookup([
+      ["US", "USD"],
+      ["CA", "CAD"],
+    ])
+  ).toEqual({
+    US: "USD",
+    CA: "CAD",
+  });
+  expect(
+    createLookup([
+      ["BE", "EUR"],
+      ["BR", "BRL"],
+      ["FI", "FIN"],
+    ])
+  ).toEqual({ BE: "EUR", BR: "BRL", FI: "FIN" });
+  expect(
+    createLookup([
+      ["CV", "CPV"],
+      ["CN", "CHN"],
+      ["CR", "CRI"],
+      ["DE", "DEU"],
+      ["IN", "IND"],
+    ])
+  ).toEqual({ CV: "CPV", CN: "CHN", CR: "CRI", DE: "DEU", IN: "IND" });
+});
 
 /*
 

Sprint-2/implement/querystring.js

@@ -6,11 +6,17 @@ function parseQueryString(queryString) {
   const keyValuePairs = queryString.split("&");
 
   for (const pair of keyValuePairs) {
-    const [key, value] = pair.split("=");
+    const equalityPosition = pair.indexOf("=");
+    if (equalityPosition == -1) {
+      continue;
+    }
+    const key = pair.slice(0, equalityPosition);
+    const value = pair.slice(equalityPosition + 1);
+    if (key === "" && value === "") {
+      continue;
+    }
     queryParams[key] = value;
   }
-
   return queryParams;
 }
-
 module.exports = parseQueryString;

Sprint-2/implement/querystring.test.js

@@ -3,10 +3,22 @@
 // Below is one test case for an edge case the implementation doesn't handle well.
 // Fix the implementation for this test, and try to think of as many other edge cases as possible - write tests and fix those too.
 
-const parseQueryString = require("./querystring.js")
+const parseQueryString = require("./querystring.js");
 
-test("parses querystring values containing =", () => {
+test("the function should return object when a string parses querystring values containing = is passed", () => {
   expect(parseQueryString("equation=x=y+1")).toEqual({
-    "equation": "x=y+1",
+    equation: "x=y+1",
+  });
+  expect(parseQueryString("equation")).toEqual({});
+  expect(parseQueryString("name=ahmed&age=29")).toEqual({
+    name: "ahmed",
+    age: "29",
+  });
+  expect(parseQueryString("q=sa3")).toEqual({ q: "sa3" });
+  expect(parseQueryString("code=future+codebetter")).toEqual({
+    code: "future+codebetter",
+  });
+  expect(parseQueryString("location=london=x=+12=2")).toEqual({
+    location: "london=x=+12=2",
   });
 });

Sprint-2/implement/tally.js

@@ -1,3 +1,17 @@
-function tally() {}
-
+function tally(myArray) {
+  if (!Array.isArray(myArray)) {
+    throw new Error();
+  } else if (myArray.length === 0) {
+    return {};
+  }
+  let tallyObject = Object.create(null);
+  for (const singleItems of myArray) {
+    if (tallyObject[singleItems] === undefined) {
+      tallyObject[singleItems] = 1;
+    } else {
+      tallyObject[singleItems] += 1;
+    }
+  }
+  return tallyObject;
+}
 module.exports = tally;

Sprint-2/implement/tally.test.js

@@ -23,12 +23,31 @@ const tally = require("./tally.js");
 // Given an empty array
 // When passed to tally
 // Then it should return an empty object
-test.todo("tally on an empty array returns an empty object");
+test("The function should return empty object when an empty array is passed to the function", () => {
+  expect(tally([])).toEqual({});
+});
 
 // Given an array with duplicate items
 // When passed to tally
 // Then it should return counts for each unique item
-
+test("The function should return an object where each key is a unique item from the array, and each index is how many times that item duplicate", () => {
+  expect(tally(["a", "a", "a", "b", "b", "b", "c", "c", "c"])).toEqual({
+    a: 3,
+    b: 3,
+    c: 3,
+  });
+  expect(
+    tally(["manchester", "manchester", "london", "london", "leeds"])
+  ).toEqual({ manchester: 2, london: 2, leeds: 1 });
+  expect(tally([1, 1, 2])).toEqual({ 1: 2, 2: 1 });
+  expect(tally(["a"])).toEqual({ a: 1 });
+  expect(tally(["a", "a", "a"])).toEqual({ a: 3 });
+});
 // Given an invalid input like a string
 // When passed to tally
 // Then it should throw an error
+test("The function should throw an error when invalid input is passed", () => {
+  expect(tally("hello")).toThrow;
+  expect(tally(134)).toThrow;
+  expect(tally({ a: 1, b: 3, d: 2 })).toThrow;
+});

Sprint-2/interpret/invert.js

@@ -17,13 +17,29 @@ function invert(obj) {
 }
 
 // a) What is the current return value when invert is called with { a : 1 }
+// the current return value when invert is called with { a:1 } is  { key: 1 }
 
 // b) What is the current return value when invert is called with { a: 1, b: 2 }
+// the current return value  when invert is called with { a: 1, b: 2 } is  { key: 2}
 
 // c) What is the target return value when invert is called with {a : 1, b: 2}
+// the target return value when invert is called with {a : 1, b: 2} is { '1':'a','2':'b'}
 
 // c) What does Object.entries return? Why is it needed in this program?
+// Object.entries is needed because it will gave as the access of the key and value by separating each key value pair.
 
 // d) Explain why the current return value is different from the target output
+/*the current value is different from the targeted value because the for loop already give as access for the key value pairs 
+but when we declare a new object the function where looking the word key in the loop because it was dot notation and taking the 
+word key and pairing it withe the last loop value. */
 
 // e) Fix the implementation of invert (and write tests to prove it's fixed!)
+/*  function invert(obj) {
+     const invertedObj = {};
+
+  for (const [key, value] of Object.entries(obj)) {
+          invertedObj[value] = key;
+    }
+
+  return invertedObj;
+} */