NW6 | Pedram Amani | Module-JS1 | Week4

week-4/implement/count.test.js

@@ -15,3 +15,19 @@
 // And a character char that does not exist within the case-sensitive str,
 // When the function is called with these inputs,
 // Then it should return 0, indicating that no occurrences of the char were found in the case-sensitive str.
+
+function countChar(str, char) {
+  const charsArray = str.split("");
+  const occurrences = charsArray.filter((currentChar) => {
+    return currentChar === char;
+  });
+  return occurrences.length;
+}
+
+test("counts the number of times a character occurs in a string", function () {
+  expect(countChar("aaaaa", "a")).toBe(5);
+  expect(countChar("apple", "b")).toBe(0);
+  expect(countChar("book", "o")).toBe(2);
+  expect(countChar("hello", "e")).toBe(1);
+  expect(countChar("world", "z")).toBe(0);
+});

week-4/implement/get-ordinal-number.test.js

@@ -2,3 +2,38 @@
 
 // continue testing and implementing getOrdinalNumber for additional cases
 // Write your tests using Jest - remember to run your tests often for continual feedback
+
+function getOrdinalNumber(num) {
+  if (!Number.isInteger(num) || num < 1) {
+    return "Invalid input";
+  }
+
+  const lastDigit = num % 10;
+
+  let suffix;
+  if (lastDigit === 1 && num !== 11) {
+    suffix = "st";
+  } else if (lastDigit === 2 && num !== 12) {
+    suffix = "nd";
+  } else if (lastDigit === 3 && num !== 13) {
+    suffix = "rd";
+  } else {
+    suffix = "th";
+  }
+
+  return `${num}${suffix}`;
+}
+
+test("converts any number to an ordinal number", function () {
+  expect(getOrdinalNumber(1)).toBe("1st");
+  expect(getOrdinalNumber(11)).toBe("11th");
+  expect(getOrdinalNumber(21)).toBe("21st");
+  expect(getOrdinalNumber(12)).toBe("12th");
+  expect(getOrdinalNumber(13)).toBe("13th");
+  expect(getOrdinalNumber(-36 / -12)).toBe("3rd");
+  expect(getOrdinalNumber(0)).toBe("Invalid input");
+  expect(getOrdinalNumber(-26)).toBe("Invalid input");
+  expect(getOrdinalNumber(3.14)).toBe("Invalid input");
+  expect(getOrdinalNumber(4 / 5)).toBe("Invalid input");
+  expect(getOrdinalNumber("Hello")).toBe("Invalid input");
+});

week-4/implement/is-prime.test.js

@@ -1,3 +1,47 @@
 // Given a positive integer num,
 // When the isPrime function is called with num as input,
 // Then it should return a boolean representing whether the num is prime
+
+function isPrime(num) {
+  if (isNaN(num) || num <= 0 || Number.isInteger(num) !== true) {
+    return "Invalid input, please enter a positive integer number";
+  } else if (num === 2) {
+    return true;
+  } else if (num % 2 === 0 || num === 1) {
+    return false;
+  } else {
+    for (let i = 3; i <= Math.sqrt(num); i += 2) {
+      if (num % i === 0) {
+        return false;
+      }
+    }
+    return true;
+  }
+}
+
+test("returns a boolean representing whether the num is prime", function () {
+  expect(isPrime(1)).toBe(false);
+  expect(isPrime(2)).toBe(true);
+  expect(isPrime(3)).toBe(true);
+  expect(isPrime(4)).toBe(false);
+  expect(isPrime(5)).toBe(true);
+  expect(isPrime(6)).toBe(false);
+  expect(isPrime(7)).toBe(true);
+  expect(isPrime(8)).toBe(false);
+  expect(isPrime(11)).toBe(true);
+  expect(isPrime(0)).toBe(
+    "Invalid input, please enter a positive integer number"
+  );
+  expect(isPrime(2.2)).toBe(
+    "Invalid input, please enter a positive integer number"
+  );
+  expect(isPrime(0.5)).toBe(
+    "Invalid input, please enter a positive integer number"
+  );
+  expect(isPrime(-7)).toBe(
+    "Invalid input, please enter a positive integer number"
+  );
+  expect(isPrime("abc")).toBe(
+    "Invalid input, please enter a positive integer number"
+  );
+});