London | 26-ITP-May | Bisrat Tesfay | Sprint 3 | Practice TDD

Sprint-3/2-practice-tdd/count.js

@@ -1,5 +1,11 @@
 function countChar(stringOfCharacters, findCharacter) {
-  return 5
+  let count = 0;
+  for (let i = 0; i < stringOfCharacters.length; i++) {
+    if (stringOfCharacters[i] === findCharacter) {
+      count++; // count = count + 1;
+    }
+  }
+  return count;
 }
 
 module.exports = countChar;

Sprint-3/2-practice-tdd/count.test.js

@@ -17,8 +17,22 @@ test("should count multiple occurrences of a character", () => {
   expect(count).toEqual(5);
 });
 
+test("should count multiple occurrences of a different character", () => {
+  const str = "banana";
+  const char = "n";
+  const count = countChar(str, char);
+  expect(count).toEqual(2);
+});
+
 // Scenario: No Occurrences
 // Given the input string `str`,
 // And a character `char` that does not exist within `str`.
 // When the function is called with these inputs,
 // Then it should return 0, indicating that no occurrences of `char` were found.
+
+test("should return 0 when no occurrences of a character are found", () => {
+  const str = "Bisrat";
+  const char = "z";
+  const count = countChar(str, char);
+  expect(count).toEqual(0);
+});

Sprint-3/2-practice-tdd/get-ordinal-number.js

@@ -1,5 +1,24 @@
 function getOrdinalNumber(num) {
-  return "1st";
+  const lastDigit = num % 10;
+  const lastTwoDigits = num % 100;
+
+  if (!Number.isInteger(num) || num < 1) {
+    throw new Error("Input must be a positive integer");
+  }
+
+  if (lastDigit === 1 && lastTwoDigits !== 11) {
+    return `${num}st`;
+  }
+
+  if (lastDigit === 2 && lastTwoDigits !== 12) {
+    return `${num}nd`;
+  }
+
+  if (lastDigit === 3 && lastTwoDigits !== 13) {
+    return `${num}rd`;
+  }
+
+  return `${num}th`;
 }
 
 module.exports = getOrdinalNumber;

Sprint-3/2-practice-tdd/get-ordinal-number.test.js

@@ -18,3 +18,48 @@ test("should append 'st' for numbers ending with 1, except those ending with 11"
   expect(getOrdinalNumber(21)).toEqual("21st");
   expect(getOrdinalNumber(131)).toEqual("131st");
 });
+
+// Case 2: Numbers ending with 2 (except 12)
+test("should append 'nd' for numbers ending with 2, except those ending with 12", () => {
+  expect(getOrdinalNumber(2)).toEqual("2nd");
+  expect(getOrdinalNumber(22)).toEqual("22nd");
+  expect(getOrdinalNumber(132)).toEqual("132nd");
+});
+
+// Case 3: Numbers ending with 3 (except 13)
+test("should append 'rd' for numbers ending with 3, except those ending with 13", () => {
+  expect(getOrdinalNumber(3)).toEqual("3rd");
+  expect(getOrdinalNumber(23)).toEqual("23rd");
+  expect(getOrdinalNumber(133)).toEqual("133rd");
+});
+
+// Case 4: Numbers ending with 11, 12, or 13
+test("should append 'th' for numbers ending with 11, 12, or 13", () => {
+  expect(getOrdinalNumber(11)).toEqual("11th");
+  expect(getOrdinalNumber(12)).toEqual("12th");
+  expect(getOrdinalNumber(13)).toEqual("13th");
+});
+
+// Case 5: All other numbers
+test("should append 'th' for all other numbers", () => {
+  expect(getOrdinalNumber(4)).toEqual("4th");
+  expect(getOrdinalNumber(20)).toEqual("20th");
+  expect(getOrdinalNumber(100)).toEqual("100th");
+});
+
+// Case 6: Negative numbers
+test("should throw an error for negative numbers", () => {
+  expect(() => getOrdinalNumber(-1)).toThrow();
+  expect(() => getOrdinalNumber(-25)).toThrow();
+});
+
+// Case 7: Decimal numbers
+test("should throw an error for decimal numbers", () => {
+  expect(() => getOrdinalNumber(1.5)).toThrow();
+  expect(() => getOrdinalNumber(22.7)).toThrow();
+});
+
+// Case 8: Zero
+test("should throw an error for zero", () => {
+  expect(() => getOrdinalNumber(0)).toThrow();
+});

Sprint-3/2-practice-tdd/repeat-str.js

@@ -1,7 +1,16 @@
-function repeatStr() {
+function repeatStr(stringOfCharacters, count) {
   // Your implementation of this function must *not* call String.prototype.repeat (https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/repeat).
   // The goal is to re-implement that function, not to use it.
-  return "hellohellohello";
+
+  if (count === 0) {
+    return "";
+  }
+
+  if (count > 0) {
+    return repeatStr(stringOfCharacters, count - 1) + stringOfCharacters;
+  }
+
+  throw new Error("Invalid input: count must be a non-negative integer");
 }
 
 module.exports = repeatStr;

Sprint-3/2-practice-tdd/repeat-str.test.js

@@ -21,12 +21,34 @@ test("should repeat the string count times", () => {
 // When the repeatStr function is called with these inputs,
 // Then it should return the original `str` without repetition.
 
+test("should return the original string when count is 1", () => {
+  const str = "world";
+  const count = 1;
+  const repeatedStr = repeatStr(str, count);
+  expect(repeatedStr).toEqual("world");
+});
+
 // Case: Handle count of 0:
 // Given a target string `str` and a `count` equal to 0,
 // When the repeatStr function is called with these inputs,
 // Then it should return an empty string.
 
+test("should return an empty string when count is 0", () => {
+  const str = "test";
+  const count = 0;
+  const repeatedStr = repeatStr(str, count);
+  expect(repeatedStr).toEqual("");
+});
+
 // Case: Handle negative count:
 // Given a target string `str` and a negative integer `count`,
 // When the repeatStr function is called with these inputs,
 // Then it should throw an error, as negative counts are not valid.
+
+test("should throw an error when count is negative", () => {
+  const str = "error";
+  const count = -2;
+  expect(() => repeatStr(str, count)).toThrow(
+    "Invalid input: count must be a non-negative integer"
+  );
+});