Glasgow class 5 - Jalal - JavaScript Core 2 - Week1

mandatory/1-writers.js

@@ -6,16 +6,22 @@
   You might think "This is madness!" but in everyday coding life
   it is quite a frequent combination. Just think about what benefits we can get from this construct.
 
-  An object lets you store multiple values in a single variable, then you can store complex objects in an array.
-  Let's assume you have a list of data about people names and their birthday and you would like to print each name
+  An object lets you store multiple values in a single variable, then you can store 
+  complex objects in an array.
+  Let's assume you have a list of data about people names and their birthday 
+  and you would like to print each name
   with corresponding birthday together. 
 
   Storing these pieces of information in different arrays and then pairing them up
-  makes the iteration unnecessarily complicated, code will be less intuitive, needs extra cognitive effort to
-  reason about and last but not least it can be error-prone (for example, you match up the wrong birthday to a name).
-
-  In this exercise you will practice how to access Objects stored in an Array and their properties. You already know 
-  different ways of looping through Arrays, it won't be different in this case. The only extra step is that you have to 
+  makes the iteration unnecessarily complicated, code will be less intuitive, 
+  needs extra cognitive effort to
+  reason about and last but not least it can be error-prone 
+  (for example, you match up the wrong birthday to a name).
+
+  In this exercise you will practice how to access Objects stored in an Array 
+  and their properties. You already know 
+  different ways of looping through Arrays, 
+  it won't be different in this case. The only extra step is that you have to 
   use values inside Objects.
 */
 
@@ -55,7 +61,7 @@ let writers = [
     occupation: "writer",
     age: 49,
     alive: true,
-  }
+  },
 ];
 
 /*
@@ -68,7 +74,37 @@ Exercise 1:
 */
 function logAllWriters() {
   // write your code to log all writers here
-};
+  // for (let i = 0; i < writers.length; i++) {
+  //   console.log(
+  //     "Hi, my name is " +
+  //       writers[i].firstName +
+  //       " " +
+  //       writers[i].lastName +
+  //       ". I am" +
+  //       " " +
+  //       writers[i].age +
+  //       " years old, and work as a " +
+  //       writers[i].occupation +
+  //       "."
+  //   );
+  // }
+  writers.forEach(logWriter);
+}
+
+function logWriter(writer) {
+  console.log(
+    "Hi, my name is " +
+      writer.firstName +
+      " " +
+      writer.lastName +
+      ". I am" +
+      " " +
+      writer.age +
+      " years old, and work as a " +
+      writer.occupation +
+      "."
+  );
+}
 
 /*
 Exercise 2:
@@ -79,8 +115,25 @@ Exercise 2:
   "Writer {firstName} {lastName} died at {age} years old."
 */
 
+function diedInForty(writer) {
+  return writer.age >= 40 && writer.age <= 49 && !writer.alive;
+}
+
+function logWriter1(writer) {
+  console.log(
+    "Writer " +
+      writer.firstName +
+      " " +
+      writer.lastName +
+      " died at " +
+      writer.age +
+      " years old."
+  );
+}
+
 function logDeadWritersInTheirForties() {
   // write your code here
+  writers.filter(diedInForty).forEach(logWriter1);
 }
 
 /*
@@ -91,8 +144,26 @@ Exercise 3:
   "Hi, my name is {firstName} {lastName}. I am {age} years old."
 */
 
+function aliveInForty(writer) {
+  return writer.age >= 40 && writer.age <= 49 && writer.alive;
+}
+
+function logWriter2(writer) {
+  console.log(
+    "Hi, my name is " +
+      writer.firstName +
+      " " +
+      writer.lastName +
+      ". I am" +
+      " " +
+      writer.age +
+      " years old."
+  );
+}
+
 function logAliveWritersInTheirForties() {
   // write your code here
+  writers.filter(aliveInForty).forEach(logWriter2);
 }
 
 /* ======= TESTS - DO NOT MODIFY ===== 
@@ -101,29 +172,32 @@ function logAliveWritersInTheirForties() {
 - (Reminder: You must have run `npm install` one time before this will work!)
 */
 
-test("exercise 1", () => expectFunctionToLog(logAllWriters, [
-  "Hi, my name is Virginia Woolf. I am 59 years old, and work as a writer.",
-  "Hi, my name is Zadie Smith. I am 40 years old, and work as a writer.",
-  "Hi, my name is Jane Austen. I am 41 years old, and work as a writer.",
-  "Hi, my name is Bell Hooks. I am 63 years old, and work as a writer.",
-  "Hi, my name is Yukiko Motoya. I am 49 years old, and work as a writer."
-]));
-
-test("exercise 2", () => expectFunctionToLog(logDeadWritersInTheirForties, [
-  "Writer Jane Austen died at 41 years old."
-]));
-
-test("exercise 3", () => expectFunctionToLog(logAliveWritersInTheirForties, [
-  "Hi, my name is Zadie Smith. I am 40 years old.",
-  "Hi, my name is Yukiko Motoya. I am 49 years old."
-]));
+test("exercise 1", () =>
+  expectFunctionToLog(logAllWriters, [
+    "Hi, my name is Virginia Woolf. I am 59 years old, and work as a writer.",
+    "Hi, my name is Zadie Smith. I am 40 years old, and work as a writer.",
+    "Hi, my name is Jane Austen. I am 41 years old, and work as a writer.",
+    "Hi, my name is Bell Hooks. I am 63 years old, and work as a writer.",
+    "Hi, my name is Yukiko Motoya. I am 49 years old, and work as a writer.",
+  ]));
+
+test("exercise 2", () =>
+  expectFunctionToLog(logDeadWritersInTheirForties, [
+    "Writer Jane Austen died at 41 years old.",
+  ]));
+
+test("exercise 3", () =>
+  expectFunctionToLog(logAliveWritersInTheirForties, [
+    "Hi, my name is Zadie Smith. I am 40 years old.",
+    "Hi, my name is Yukiko Motoya. I am 49 years old.",
+  ]));
 
 function expectFunctionToLog(f, values) {
-    const consoleLogSpy = jest.spyOn(console, 'log');
-    f();
-    expect(consoleLogSpy).toBeCalledTimes(values.length);
-    values.forEach((value, i) => {
-      expect(consoleLogSpy).nthCalledWith(i+1, value);
-    });
-    consoleLogSpy.mockRestore();
-};
+  const consoleLogSpy = jest.spyOn(console, "log");
+  f();
+  expect(consoleLogSpy).toBeCalledTimes(values.length);
+  values.forEach((value, i) => {
+    expect(consoleLogSpy).nthCalledWith(i + 1, value);
+  });
+  consoleLogSpy.mockRestore();
+}

mandatory/10-cheap-diner.js

@@ -30,38 +30,61 @@ Should give the answer "Nothing :("
 **/
 
 function chooseMeal(mealArray) {
+  mealArray.sort(compareFunction);
+  // console.log(mealArray.length);
+  if (mealArray.length > 1) {
+    return mealArray[1].name;
+  } else if (mealArray.length === 1) {
+    return mealArray[0].name;
+  } else {
+    return "Nothing :(";
+  }
 }
 
+function compareFunction(a, b) {
+  if (b.price > a.price) return -1;
+  if (b.price < a.price) return 1;
+  return 0;
+}
+
+// console.log(chooseMeal([{ name: "Subway", price: 8.99 }]));
+
 /* ======= TESTS - DO MODIFY (!!!) =====
 - To run the tests for this exercise, run `npm test -- --testPathPattern 10-cheap-diner.js`
 - To run all exercises/tests in the mandatory folder, run `npm test`
 - (Reminder: You must have run `npm install` one time before this will work!)
 */
 
 test("Meal to select is last", () => {
-  expect(chooseMeal([
-    { name: "Dunkin' Donuts", price: 8.99 },
-    { name: "Captain D's", price: 13.99 },
-    { name: "Moe's Southwest Grill", price: 10.99 },
-  ])).toEqual("Moe's Southwest Grill");
+  expect(
+    chooseMeal([
+      { name: "Dunkin' Donuts", price: 8.99 },
+      { name: "Captain D's", price: 13.99 },
+      { name: "Moe's Southwest Grill", price: 10.99 },
+    ])
+  ).toEqual("Moe's Southwest Grill");
 });
 
 test("Meal to select is first", () => {
-  expect(chooseMeal([
-    { name: "Moe's Southwest Grill", price: 10.99 },
-    { name: "Dunkin' Donuts", price: 8.99 },
-    { name: "Captain D's", price: 13.99 },
-  ])).toEqual("Moe's Southwest Grill");
+  expect(
+    chooseMeal([
+      { name: "Moe's Southwest Grill", price: 10.99 },
+      { name: "Dunkin' Donuts", price: 8.99 },
+      { name: "Captain D's", price: 13.99 },
+    ])
+  ).toEqual("Moe's Southwest Grill");
 });
 
 test("Meal to select is also most expensive", () => {
-  expect(chooseMeal([
-    { name: "Burger King", price: 8.99 },
-    { name: "Wingstop", price: 9.99 },
-  ])).toEqual("Wingstop");
+  expect(
+    chooseMeal([
+      { name: "Burger King", price: 8.99 },
+      { name: "Wingstop", price: 9.99 },
+    ])
+  ).toEqual("Wingstop");
 });
 
-test("Only one meal to select", () => { 
+test("Only one meal to select", () => {
   expect(chooseMeal([{ name: "Subway", price: 8.99 }])).toEqual("Subway");
 });
 
@@ -70,10 +93,12 @@ test("No meals to select", () => {
 });
 
 test("Meal to select is second cheapest, not second most expensive", () => {
-  expect(chooseMeal([
-    { name: "Church's Chicken", price: 8.99 },
-    { name: "Smoothie King", price: 109.99 },
-    { name: "Jason's Deli", price: 22.77 },
-    { name: "Jamba Juice", price: 38.44 },
-  ])).toEqual("Jason's Deli");
+  expect(
+    chooseMeal([
+      { name: "Church's Chicken", price: 8.99 },
+      { name: "Smoothie King", price: 109.99 },
+      { name: "Jason's Deli", price: 22.77 },
+      { name: "Jamba Juice", price: 38.44 },
+    ])
+  ).toEqual("Jason's Deli");
 });

mandatory/11-choose-your-own-adventure.js

@@ -57,6 +57,7 @@ let game = {
     // object for the correct room.
     //
     // Hint: the only valid rooms are "hall", "classroom" and "library".
+    this.currentRoom = rooms[roomName];
   },
 
   move: function (direction) {
@@ -66,6 +67,24 @@ let game = {
     //
     // Hint: the room objects have north/east/south/west methods which return
     // a new room object that is in the relevant direction.
+
+    // console.log(this.currentRoom);
+    if (
+      direction === "north" ||
+      direction === "east" ||
+      direction === "west" ||
+      direction === "south"
+    ) {
+      let newRoom = this.currentRoom[direction]();
+      // console.log(newRoom);
+      if (newRoom) {
+        this.currentRoom = newRoom;
+      } else {
+        console.log("Please choose a valid direction");
+      }
+    } else {
+      console.log("Choose one of north/south/east/west only");
+    }
   },
 };
 
@@ -232,14 +251,14 @@ test("start in classroom and go west", () => {
 });
 
 // remove ".skip" if your code handles trying to go in a direction with no room (by staying in the same room)
-test.skip("start in hall and go north (to non-existent room) -> stay in same room", () => {
+test("start in hall and go north (to non-existent room) -> stay in same room", () => {
   game.currentRoom = rooms.hall;
   game.move("north");
   expect(game.currentRoom.name).toEqual("hall");
 });
 
 // remove ".skip" if your code handles trying to go in a direction that doesn't exist (by staying in the same room)
-test.skip("start in hall and go backwards (non-existent direction) -> stay in same room", () => {
+test("start in hall and go backwards (non-existent direction) -> stay in same room", () => {
   game.currentRoom = rooms.hall;
   game.move("backwards");
   expect(game.currentRoom.name).toEqual("hall");

mandatory/2-eligible-students.js

@@ -20,7 +20,13 @@
  */
 
 function eligibleStudents(attendances) {
-
+  let arr = [];
+  attendances.filter((student) => {
+    if (student.attendance >= 8) {
+      arr.push(student.name);
+    }
+  });
+  return arr;
 }
 
 /* ======= TESTS - DO NOT MODIFY ===== 
@@ -30,15 +36,19 @@ function eligibleStudents(attendances) {
 */
 
 const attendances = [
-    {name: "Ahmed", attendance: 8},
-    {name: "Clement", attendance: 10},
-    {name: "Elamin", attendance: 6},
-    {name: "Adam", attendance: 7},
-    {name: "Tayoa", attendance: 11},
-    {name: "Nina", attendance: 10},
+  { name: "Ahmed", attendance: 8 },
+  { name: "Clement", attendance: 10 },
+  { name: "Elamin", attendance: 6 },
+  { name: "Adam", attendance: 7 },
+  { name: "Tayoa", attendance: 11 },
+  { name: "Nina", attendance: 10 },
 ];
-  
+// console.log(eligibleStudents(attendances));
 test("eligibleStudents function works", () => {
-    expect(eligibleStudents(attendances)).toEqual(["Ahmed", "Clement", "Tayoa", "Nina"]);
+  expect(eligibleStudents(attendances)).toEqual([
+    "Ahmed",
+    "Clement",
+    "Tayoa",
+    "Nina",
+  ]);
 });
-