From caa5bb021f119ae5bf412a1fc02803dc37fccf62 Mon Sep 17 00:00:00 2001
From: Aklilu Mihtsun <mihtsun.app@gmail.com>
Date: Mon, 9 Nov 2026 15:25:07 +0000
Subject: [PATCH 01/22] Fix address object property access to log house number
 correctly

---
 Sprint-2/debug/address.js | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/Sprint-2/debug/address.js b/Sprint-2/debug/address.js
index 940a6af83..55a11873d 100644
--- a/Sprint-2/debug/address.js
+++ b/Sprint-2/debug/address.js
@@ -1,5 +1,9 @@
 // Predict and explain first...
 
+// I predict that the code will give undefined result, because objects access properties using the key names not indexes
+// And the square bracket will generate a reference error because the houseNumber will be treated
+//  as a variable name not property key
+
 // This code should log out the houseNumber from the address object
 // but it isn't working...
 // Fix anything that isn't working
@@ -12,4 +16,4 @@ const address = {
   postcode: "XYZ 123",
 };
 
-console.log(`My house number is ${address[0]}`);
+console.log(`My house number is ${address.houseNumber}`);

From e2397d8cbe6d665c96cc6ce2ec1c8954cdf630e9 Mon Sep 17 00:00:00 2001
From: Aklilu Mihtsun <mihtsun.app@gmail.com>
Date: Mon, 9 Nov 2026 15:27:36 +0000
Subject: [PATCH 02/22] Fix for loop to correctly iterate over object
 properties in author.js

---
 Sprint-2/debug/author.js | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/Sprint-2/debug/author.js b/Sprint-2/debug/author.js
index 8c2125977..46072c262 100644
--- a/Sprint-2/debug/author.js
+++ b/Sprint-2/debug/author.js
@@ -1,5 +1,8 @@
 // Predict and explain first...
 
+// I predict the code will generate error, because it has used for of loop which is for looping array,
+//  instead of for in loop that is for looping objects
+
 // This program attempts to log out all the property values in the object.
 // But it isn't working. Explain why first and then fix the problem
 
@@ -11,6 +14,6 @@ const author = {
   alive: true,
 };
 
-for (const value of author) {
+for (const value in author) {
   console.log(value);
 }

From df238c960edc8a9d8da1c0a78ac24d31aee739db Mon Sep 17 00:00:00 2001
From: Aklilu Mihtsun <mihtsun.app@gmail.com>
Date: Mon, 9 Nov 2026 15:40:24 +0000
Subject: [PATCH 03/22] Fix recipe.js to correctly log ingredients and improve
 comments

---
 Sprint-2/debug/recipe.js | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/Sprint-2/debug/recipe.js b/Sprint-2/debug/recipe.js
index 6cbdd22cd..07b11eeee 100644
--- a/Sprint-2/debug/recipe.js
+++ b/Sprint-2/debug/recipe.js
@@ -1,5 +1,8 @@
 // Predict and explain first...
 
+// I predict the code will not print the ingredients, because the array is not referenced,
+// and it does not have loop to go through each element of the array
+
 // This program should log out the title, how many it serves and the ingredients.
 // Each ingredient should be logged on a new line
 // How can you fix it?
@@ -10,6 +13,8 @@ const recipe = {
   ingredients: ["olive oil", "tomatoes", "salt", "pepper"],
 };
 
-console.log(`${recipe.title} serves ${recipe.serves}
-  ingredients:
-${recipe}`);
+for (const cookingIngredients of recipe.ingredients) {
+  console.log(cookingIngredients);
+}
+
+console.log(`${recipe.title} serves ${recipe.serves}`);

From 345b355ab69ee42227365b99d13c13f7ce271128 Mon Sep 17 00:00:00 2001
From: Aklilu Mihtsun <mihtsun.app@gmail.com>
Date: Tue, 10 Nov 2026 15:06:18 +0000
Subject: [PATCH 04/22] Add tests for contains function to validate object
 property checks and error handling

---
 Sprint-2/implement/contains.test.js | 37 ++++++++++++++++++++++++++++-
 1 file changed, 36 insertions(+), 1 deletion(-)

diff --git a/Sprint-2/implement/contains.test.js b/Sprint-2/implement/contains.test.js
index 719272787..72864b82c 100644
--- a/Sprint-2/implement/contains.test.js
+++ b/Sprint-2/implement/contains.test.js
@@ -1,4 +1,5 @@
 const contains = require("./contains.js");
+/// <reference types="jest" />
 
 /*
 Implement a function called contains that checks an object contains a
@@ -23,18 +24,52 @@ as an array isn't an object
 // Given an empty object
 // When passed to contains
 // Then it should return false
-test.todo("contains on empty object returns false");
+test("contains on empty object returns false", () => {
+  expect(contains({}, "a")).toBe(false);
+});
 
 // Given an object with properties
 // When passed to contains with an existing property name
 // Then it should return true
+test("contains name on object returns true", () => {
+  expect(contains({ a: 1, b: 2, c: 3 }, "a")).toBe(true);
+});
 
 // Given an object with properties
 // When passed to contains with a non-existent property name
 // Then it should return false
+test("contains name not on object returns false", () => {
+  expect(contains({ a: 1, b: 2, c: 3 }, "e")).toBe(false);
+});
 
 // Given a value that isn't an object - an array, a string, a number,
 // null, or no argument at all
 // When passed to contains
 // Then it should throw Error("contains requires an object")
 // (careful: typeof [] and typeof null are both "object")
+
+describe("when the argument is not an object", () => {
+  test("throws an error when receiving a string", () => {
+    expect(() => {
+      contains("Hello World", "e");
+    }).toThrow("contains requires an object");
+  });
+
+  test("throws an error when receiving a number", () => {
+    expect(() => {
+      contains(1234, "a");
+    }).toThrow("contains requires an object");
+  });
+
+  test("throws an error when receiving an array", () => {
+    expect(() => {
+      contains(["a", "b", "c"], "a");
+    }).toThrow("contains requires an object");
+  });
+
+  test("throws an error when receiving null", () => {
+    expect(() => {
+      contains(null, "a");
+    }).toThrow("contains requires an object");
+  });
+});

From 2ae731203fb2cdb9f268c7ab6a1dc0a82fd3b38b Mon Sep 17 00:00:00 2001
From: Aklilu Mihtsun <mihtsun.app@gmail.com>
Date: Tue, 10 Nov 2026 15:06:25 +0000
Subject: [PATCH 05/22] Implement contains function to check for property
 existence in an object

---
 Sprint-2/implement/contains.js | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/Sprint-2/implement/contains.js b/Sprint-2/implement/contains.js
index cd779308a..e2c7fe4d6 100644
--- a/Sprint-2/implement/contains.js
+++ b/Sprint-2/implement/contains.js
@@ -1,3 +1,12 @@
-function contains() {}
+function contains(object, name) {
+  if (typeof object !== "object" || Array.isArray(object) || object === null) {
+    throw new Error("contains requires an object");
+  }
+
+  if (name in object) {
+    return true;
+  }
+  return false;
+}
 
 module.exports = contains;

From fd4f6f57111ce280ae773342770d9f289f158ad9 Mon Sep 17 00:00:00 2001
From: Aklilu Mihtsun <mihtsun.app@gmail.com>
Date: Tue, 10 Nov 2026 15:06:44 +0000
Subject: [PATCH 06/22] Add jsconfig.json and update package.json for Jest type
 definitions

---
 Sprint-2/jsconfig.json     |   6 +
 Sprint-2/package-lock.json | 405 +++++++++++++++++++++++++++----------
 Sprint-2/package.json      |   1 +
 3 files changed, 307 insertions(+), 105 deletions(-)
 create mode 100644 Sprint-2/jsconfig.json

diff --git a/Sprint-2/jsconfig.json b/Sprint-2/jsconfig.json
new file mode 100644
index 000000000..f1ce55706
--- /dev/null
+++ b/Sprint-2/jsconfig.json
@@ -0,0 +1,6 @@
+{
+  "compilerOptions": {
+    "types": ["jest"]
+  },
+  "exclude": ["node_modules"]
+}
diff --git a/Sprint-2/package-lock.json b/Sprint-2/package-lock.json
index 9b4c725d6..933a0f14c 100644
--- a/Sprint-2/package-lock.json
+++ b/Sprint-2/package-lock.json
@@ -9,6 +9,7 @@
       "version": "1.0.0",
       "license": "ISC",
       "devDependencies": {
+        "@types/jest": "^30.0.0",
         "jest": "^29.7.0"
       }
     },
@@ -27,14 +28,15 @@
       }
     },
     "node_modules/@babel/code-frame": {
-      "version": "7.25.7",
-      "resolved": "https://registry.npmjs.org/@babel/code-frame/-/code-frame-7.25.7.tgz",
-      "integrity": "sha512-0xZJFNE5XMpENsgfHYTw8FbX4kv53mFLn2i3XPoq69LyhYSCBJtitaHx9QnsVTrsogI4Z3+HtEfZ2/GFPOtf5g==",
+      "version": "7.29.7",
+      "resolved": "https://registry.npmjs.org/@babel/code-frame/-/code-frame-7.29.7.tgz",
+      "integrity": "sha512-Aup7aUOfpbAUg2ROOJN6Iw5f9DMBlzu0mIkm/malLQFN/YQgO48wCj0Kxa3sEHJvPVFg7siR+qRInwXd2qhQKw==",
       "dev": true,
       "license": "MIT",
       "dependencies": {
-        "@babel/highlight": "^7.25.7",
-        "picocolors": "^1.0.0"
+        "@babel/helper-validator-identifier": "^7.29.7",
+        "js-tokens": "^4.0.0",
+        "picocolors": "^1.1.1"
       },
       "engines": {
         "node": ">=6.9.0"
@@ -182,9 +184,9 @@
       }
     },
     "node_modules/@babel/helper-validator-identifier": {
-      "version": "7.25.7",
-      "resolved": "https://registry.npmjs.org/@babel/helper-validator-identifier/-/helper-validator-identifier-7.25.7.tgz",
-      "integrity": "sha512-AM6TzwYqGChO45oiuPqwL2t20/HdMC1rTPAesnBCgPCSF1x3oN9MVUwQV2iyz4xqWrctwK5RNC8LV22kaQCNYg==",
+      "version": "7.29.7",
+      "resolved": "https://registry.npmjs.org/@babel/helper-validator-identifier/-/helper-validator-identifier-7.29.7.tgz",
+      "integrity": "sha512-qehxGkRj55h/ff8EMaJ+cYhyaKlHIxqYDn682wQD7RNp9UujOQsHog2uS0r2vzr4pW+sXf90NeeayjcNaX3fFg==",
       "dev": true,
       "license": "MIT",
       "engines": {
@@ -215,100 +217,6 @@
         "node": ">=6.9.0"
       }
     },
-    "node_modules/@babel/highlight": {
-      "version": "7.25.7",
-      "resolved": "https://registry.npmjs.org/@babel/highlight/-/highlight-7.25.7.tgz",
-      "integrity": "sha512-iYyACpW3iW8Fw+ZybQK+drQre+ns/tKpXbNESfrhNnPLIklLbXr7MYJ6gPEd0iETGLOK+SxMjVvKb/ffmk+FEw==",
-      "dev": true,
-      "license": "MIT",
-      "dependencies": {
-        "@babel/helper-validator-identifier": "^7.25.7",
-        "chalk": "^2.4.2",
-        "js-tokens": "^4.0.0",
-        "picocolors": "^1.0.0"
-      },
-      "engines": {
-        "node": ">=6.9.0"
-      }
-    },
-    "node_modules/@babel/highlight/node_modules/ansi-styles": {
-      "version": "3.2.1",
-      "resolved": "https://registry.npmjs.org/ansi-styles/-/ansi-styles-3.2.1.tgz",
-      "integrity": "sha512-VT0ZI6kZRdTh8YyJw3SMbYm/u+NqfsAxEpWO0Pf9sq8/e94WxxOpPKx9FR1FlyCtOVDNOQ+8ntlqFxiRc+r5qA==",
-      "dev": true,
-      "license": "MIT",
-      "dependencies": {
-        "color-convert": "^1.9.0"
-      },
-      "engines": {
-        "node": ">=4"
-      }
-    },
-    "node_modules/@babel/highlight/node_modules/chalk": {
-      "version": "2.4.2",
-      "resolved": "https://registry.npmjs.org/chalk/-/chalk-2.4.2.tgz",
-      "integrity": "sha512-Mti+f9lpJNcwF4tWV8/OrTTtF1gZi+f8FqlyAdouralcFWFQWF2+NgCHShjkCb+IFBLq9buZwE1xckQU4peSuQ==",
-      "dev": true,
-      "license": "MIT",
-      "dependencies": {
-        "ansi-styles": "^3.2.1",
-        "escape-string-regexp": "^1.0.5",
-        "supports-color": "^5.3.0"
-      },
-      "engines": {
-        "node": ">=4"
-      }
-    },
-    "node_modules/@babel/highlight/node_modules/color-convert": {
-      "version": "1.9.3",
-      "resolved": "https://registry.npmjs.org/color-convert/-/color-convert-1.9.3.tgz",
-      "integrity": "sha512-QfAUtd+vFdAtFQcC8CCyYt1fYWxSqAiK2cSD6zDB8N3cpsEBAvRxp9zOGg6G/SHHJYAT88/az/IuDGALsNVbGg==",
-      "dev": true,
-      "license": "MIT",
-      "dependencies": {
-        "color-name": "1.1.3"
-      }
-    },
-    "node_modules/@babel/highlight/node_modules/color-name": {
-      "version": "1.1.3",
-      "resolved": "https://registry.npmjs.org/color-name/-/color-name-1.1.3.tgz",
-      "integrity": "sha512-72fSenhMw2HZMTVHeCA9KCmpEIbzWiQsjN+BHcBbS9vr1mtt+vJjPdksIBNUmKAW8TFUDPJK5SUU3QhE9NEXDw==",
-      "dev": true,
-      "license": "MIT"
-    },
-    "node_modules/@babel/highlight/node_modules/escape-string-regexp": {
-      "version": "1.0.5",
-      "resolved": "https://registry.npmjs.org/escape-string-regexp/-/escape-string-regexp-1.0.5.tgz",
-      "integrity": "sha512-vbRorB5FUQWvla16U8R/qgaFIya2qGzwDrNmCZuYKrbdSUMG6I1ZCGQRefkRVhuOkIGVne7BQ35DSfo1qvJqFg==",
-      "dev": true,
-      "license": "MIT",
-      "engines": {
-        "node": ">=0.8.0"
-      }
-    },
-    "node_modules/@babel/highlight/node_modules/has-flag": {
-      "version": "3.0.0",
-      "resolved": "https://registry.npmjs.org/has-flag/-/has-flag-3.0.0.tgz",
-      "integrity": "sha512-sKJf1+ceQBr4SMkvQnBDNDtf4TXpVhVGateu0t918bl30FnbE2m4vNLX+VWe/dpjlb+HugGYzW7uQXH98HPEYw==",
-      "dev": true,
-      "license": "MIT",
-      "engines": {
-        "node": ">=4"
-      }
-    },
-    "node_modules/@babel/highlight/node_modules/supports-color": {
-      "version": "5.5.0",
-      "resolved": "https://registry.npmjs.org/supports-color/-/supports-color-5.5.0.tgz",
-      "integrity": "sha512-QjVjwdXIt408MIiAqCX4oUKsgU2EqAGzs2Ppkm4aQYbjm+ZEWEcW4SfFNTr4uMNZma0ey4f5lgLrkB0aX0QMow==",
-      "dev": true,
-      "license": "MIT",
-      "dependencies": {
-        "has-flag": "^3.0.0"
-      },
-      "engines": {
-        "node": ">=4"
-      }
-    },
     "node_modules/@babel/parser": {
       "version": "7.25.8",
       "resolved": "https://registry.npmjs.org/@babel/parser/-/parser-7.25.8.tgz",
@@ -713,6 +621,16 @@
         }
       }
     },
+    "node_modules/@jest/diff-sequences": {
+      "version": "30.5.0",
+      "resolved": "https://registry.npmjs.org/@jest/diff-sequences/-/diff-sequences-30.5.0.tgz",
+      "integrity": "sha512-OsqBjHXCn8cadasoAZBP6nWYvMsRhpMzGXTpxJ5aO04NlbdhIz+FVe3q49l0AwVhsz/cEmIpBes6gAFl1/dWQg==",
+      "dev": true,
+      "license": "MIT",
+      "engines": {
+        "node": "^18.14.0 || ^20.0.0 || ^22.0.0 || >=24.0.0"
+      }
+    },
     "node_modules/@jest/environment": {
       "version": "29.7.0",
       "resolved": "https://registry.npmjs.org/@jest/environment/-/environment-29.7.0.tgz",
@@ -774,6 +692,16 @@
         "node": "^14.15.0 || ^16.10.0 || >=18.0.0"
       }
     },
+    "node_modules/@jest/get-type": {
+      "version": "30.5.0",
+      "resolved": "https://registry.npmjs.org/@jest/get-type/-/get-type-30.5.0.tgz",
+      "integrity": "sha512-9/2VUPitAjmBzbvDvqrxmvB7BzWsBW0WmkkojX1ODuxX1NLGxx9gfaZpHB0z8DtJ9uhGNmZG/VXBhf8uO0OV8Q==",
+      "dev": true,
+      "license": "MIT",
+      "engines": {
+        "node": "^18.14.0 || ^20.0.0 || ^22.0.0 || >=24.0.0"
+      }
+    },
     "node_modules/@jest/globals": {
       "version": "29.7.0",
       "resolved": "https://registry.npmjs.org/@jest/globals/-/globals-29.7.0.tgz",
@@ -790,6 +718,46 @@
         "node": "^14.15.0 || ^16.10.0 || >=18.0.0"
       }
     },
+    "node_modules/@jest/pattern": {
+      "version": "30.5.0",
+      "resolved": "https://registry.npmjs.org/@jest/pattern/-/pattern-30.5.0.tgz",
+      "integrity": "sha512-HdNQYSdRTEBNrginaqzQtTjG0HRMfrra/z6Ok7uL3S87vSlarIVohEsJsSj5edu3MiHoHjAkvPROz5ZjoKai+w==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@types/node": "*",
+        "jest-regex-util": "30.5.0"
+      },
+      "engines": {
+        "node": "^18.14.0 || ^20.0.0 || ^22.0.0 || >=24.0.0"
+      }
+    },
+    "node_modules/@jest/pattern/node_modules/jest-regex-util": {
+      "version": "30.5.0",
+      "resolved": "https://registry.npmjs.org/jest-regex-util/-/jest-regex-util-30.5.0.tgz",
+      "integrity": "sha512-Mg0WK7A6xRHLSA1udJ8y9f3lM0uUhFTBnLKzwPmqB9AylvpleJ6BLemR8K9dK27DY+cesDryoA7yLZCAHsPG1A==",
+      "dev": true,
+      "license": "MIT",
+      "engines": {
+        "node": "^18.14.0 || ^20.0.0 || ^22.0.0 || >=24.0.0"
+      }
+    },
+    "node_modules/@jest/react-is-18": {
+      "name": "react-is",
+      "version": "18.3.1",
+      "resolved": "https://registry.npmjs.org/react-is/-/react-is-18.3.1.tgz",
+      "integrity": "sha512-/LLMVyas0ljjAtoYiPqYiL8VWXzUUdThrmU5+n20DZv+a+ClRoevUzw5JxU+Ieh5/c87ytoTBV9G1FiKfNJdmg==",
+      "dev": true,
+      "license": "MIT"
+    },
+    "node_modules/@jest/react-is-19": {
+      "name": "react-is",
+      "version": "19.3.1",
+      "resolved": "https://registry.npmjs.org/react-is/-/react-is-19.3.1.tgz",
+      "integrity": "sha512-RRieF6IyxQBkcK6pP8xOHprLTPW6QjRkbGdImtqNme+/hYVwCZkLQLdlZGOhUqXwkS9IEynaGvPJtv6XB/cz0Q==",
+      "dev": true,
+      "license": "MIT"
+    },
     "node_modules/@jest/reporters": {
       "version": "29.7.0",
       "resolved": "https://registry.npmjs.org/@jest/reporters/-/reporters-29.7.0.tgz",
@@ -1101,6 +1069,233 @@
         "@types/istanbul-lib-report": "*"
       }
     },
+    "node_modules/@types/jest": {
+      "version": "30.0.0",
+      "resolved": "https://registry.npmjs.org/@types/jest/-/jest-30.0.0.tgz",
+      "integrity": "sha512-XTYugzhuwqWjws0CVz8QpM36+T+Dz5mTEBKhNs/esGLnCIlGdRy+Dq78NRjd7ls7r8BC8ZRMOrKlkO1hU0JOwA==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "expect": "^30.0.0",
+        "pretty-format": "^30.0.0"
+      }
+    },
+    "node_modules/@types/jest/node_modules/@jest/expect-utils": {
+      "version": "30.5.2",
+      "resolved": "https://registry.npmjs.org/@jest/expect-utils/-/expect-utils-30.5.2.tgz",
+      "integrity": "sha512-d/HOLSrJUlBIl6n3LzOa7cjW3xdePm5H5gQw2lixZ/0h157l9sw3mLblzFqnPcTbhDzhRQdBOX3A3KcG73nm5Q==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@jest/get-type": "30.5.0"
+      },
+      "engines": {
+        "node": "^18.14.0 || ^20.0.0 || ^22.0.0 || >=24.0.0"
+      }
+    },
+    "node_modules/@types/jest/node_modules/@jest/schemas": {
+      "version": "30.5.0",
+      "resolved": "https://registry.npmjs.org/@jest/schemas/-/schemas-30.5.0.tgz",
+      "integrity": "sha512-/hunigyNpc4RCjC0VaW3f5RCUZVM2+WQ65qP7z083Gmvac7or2LI50XVNOtE4YPgBpV0yxYiAgorAPGniCoJmg==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@sinclair/typebox": "^0.34.0"
+      },
+      "engines": {
+        "node": "^18.14.0 || ^20.0.0 || ^22.0.0 || >=24.0.0"
+      }
+    },
+    "node_modules/@types/jest/node_modules/@jest/types": {
+      "version": "30.5.1",
+      "resolved": "https://registry.npmjs.org/@jest/types/-/types-30.5.1.tgz",
+      "integrity": "sha512-LvVYn83nnXPl+Rg98nvcFgjx6nRMTArhSn6RAX/w3ELn54S8A42TYZvsCMdGUqTM8S0wyXbtlQdU6Hi6dykj9g==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@jest/pattern": "30.5.0",
+        "@jest/schemas": "30.5.0",
+        "@types/istanbul-lib-coverage": "^2.0.6",
+        "@types/istanbul-reports": "^3.0.4",
+        "@types/node": "*",
+        "@types/yargs": "^17.0.33",
+        "chalk": "^4.1.2"
+      },
+      "engines": {
+        "node": "^18.14.0 || ^20.0.0 || ^22.0.0 || >=24.0.0"
+      }
+    },
+    "node_modules/@types/jest/node_modules/@sinclair/typebox": {
+      "version": "0.34.52",
+      "resolved": "https://registry.npmjs.org/@sinclair/typebox/-/typebox-0.34.52.tgz",
+      "integrity": "sha512-XiMQh7qqVlxZzcVD+kkGMNGMzcTrDMLWI7S4x7z1MkCkbDPrekpZXEUK0eZqZFMuHQg2a2DZOcDIh9o5v3Gonw==",
+      "dev": true,
+      "license": "MIT"
+    },
+    "node_modules/@types/jest/node_modules/ansi-styles": {
+      "version": "5.2.0",
+      "resolved": "https://registry.npmjs.org/ansi-styles/-/ansi-styles-5.2.0.tgz",
+      "integrity": "sha512-Cxwpt2SfTzTtXcfOlzGEee8O+c+MmUgGrNiBcXnuWxuFJHe6a5Hz7qwhwe5OgaSYI0IJvkLqWX1ASG+cJOkEiA==",
+      "dev": true,
+      "license": "MIT",
+      "engines": {
+        "node": ">=10"
+      },
+      "funding": {
+        "url": "https://github.com/chalk/ansi-styles?sponsor=1"
+      }
+    },
+    "node_modules/@types/jest/node_modules/ci-info": {
+      "version": "4.5.0",
+      "resolved": "https://registry.npmjs.org/ci-info/-/ci-info-4.5.0.tgz",
+      "integrity": "sha512-d1uM8k5UZEyPza1n/MG3ko8nKupKN0KJpFsipgPcgaCCvV+IqIfJ+NzTjetlLM+UcXZx3+cLrNr76+eAO7G1Mw==",
+      "dev": true,
+      "funding": [
+        {
+          "type": "github",
+          "url": "https://github.com/sponsors/sibiraj-s"
+        }
+      ],
+      "license": "MIT",
+      "engines": {
+        "node": ">=8"
+      }
+    },
+    "node_modules/@types/jest/node_modules/expect": {
+      "version": "30.5.2",
+      "resolved": "https://registry.npmjs.org/expect/-/expect-30.5.2.tgz",
+      "integrity": "sha512-0LNuMvs8/5mRYhnCR4k+lGV7fqPMs6Bnksda4S3zsCUmdxBpAn4zU4NNzXdq1pMKe/H4W5t/zVIDSJ/H3e0vDA==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@jest/expect-utils": "30.5.2",
+        "@jest/get-type": "30.5.0",
+        "jest-matcher-utils": "30.5.2",
+        "jest-message-util": "30.5.1",
+        "jest-mock": "30.5.2",
+        "jest-util": "30.5.1"
+      },
+      "engines": {
+        "node": "^18.14.0 || ^20.0.0 || ^22.0.0 || >=24.0.0"
+      }
+    },
+    "node_modules/@types/jest/node_modules/jest-diff": {
+      "version": "30.5.2",
+      "resolved": "https://registry.npmjs.org/jest-diff/-/jest-diff-30.5.2.tgz",
+      "integrity": "sha512-rBtHnI6BWTiWj3lM7fOLVfChx7R9B0u9VV3PRHawKs79x6ZjW1QoSrKenaigNGWlvhtoi2BqvDbABDie+Os3xQ==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@jest/diff-sequences": "30.5.0",
+        "@jest/get-type": "30.5.0",
+        "chalk": "^4.1.2",
+        "pretty-format": "30.5.1"
+      },
+      "engines": {
+        "node": "^18.14.0 || ^20.0.0 || ^22.0.0 || >=24.0.0"
+      }
+    },
+    "node_modules/@types/jest/node_modules/jest-matcher-utils": {
+      "version": "30.5.2",
+      "resolved": "https://registry.npmjs.org/jest-matcher-utils/-/jest-matcher-utils-30.5.2.tgz",
+      "integrity": "sha512-lFkB365PTIHOhPzwrb9T6gvlDnPpOZ7/c3ewOKKB7bzztqjVrtlyRL2MkyfJXpyY2u2SKw001JKrTx14fBUFcQ==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@jest/get-type": "30.5.0",
+        "chalk": "^4.1.2",
+        "jest-diff": "30.5.2",
+        "pretty-format": "30.5.1"
+      },
+      "engines": {
+        "node": "^18.14.0 || ^20.0.0 || ^22.0.0 || >=24.0.0"
+      }
+    },
+    "node_modules/@types/jest/node_modules/jest-message-util": {
+      "version": "30.5.1",
+      "resolved": "https://registry.npmjs.org/jest-message-util/-/jest-message-util-30.5.1.tgz",
+      "integrity": "sha512-UdQlLdd9wL/Ys7xRErckqwD6wPlSZYueosSWuHc1r2ztGLwlgPvtSJq2+BPEgaEY13WLvfFbmhTj8pba0Sd1jg==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@babel/code-frame": "^7.27.1",
+        "@jest/types": "30.5.1",
+        "@types/stack-utils": "^2.0.3",
+        "chalk": "^4.1.2",
+        "graceful-fs": "^4.2.11",
+        "jest-util": "30.5.1",
+        "picomatch": "^4.0.3",
+        "pretty-format": "30.5.1",
+        "slash": "^3.0.0",
+        "stack-utils": "^2.0.6"
+      },
+      "engines": {
+        "node": "^18.14.0 || ^20.0.0 || ^22.0.0 || >=24.0.0"
+      }
+    },
+    "node_modules/@types/jest/node_modules/jest-mock": {
+      "version": "30.5.2",
+      "resolved": "https://registry.npmjs.org/jest-mock/-/jest-mock-30.5.2.tgz",
+      "integrity": "sha512-KTHb37Fhj8xY8qPFvTFaFJHcdsumQp+ExsUlgoX232Agmc706gagBs53+CYvulV7MVQo9AgXOUxsqzzVBoJlrA==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@jest/expect-utils": "30.5.2",
+        "@jest/types": "30.5.1",
+        "@types/node": "*",
+        "jest-util": "30.5.1"
+      },
+      "engines": {
+        "node": "^18.14.0 || ^20.0.0 || ^22.0.0 || >=24.0.0"
+      }
+    },
+    "node_modules/@types/jest/node_modules/jest-util": {
+      "version": "30.5.1",
+      "resolved": "https://registry.npmjs.org/jest-util/-/jest-util-30.5.1.tgz",
+      "integrity": "sha512-yKuxmNy2rSbTXw+3SIPanJo+nV4/BS1p26v44IYBFMsswSQySfMMcPHErnOncda7i9HEz0q605rIhSTBVgrZTg==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@jest/types": "30.5.1",
+        "@types/node": "*",
+        "chalk": "^4.1.2",
+        "ci-info": "^4.2.0",
+        "graceful-fs": "^4.2.11",
+        "picomatch": "^4.0.3"
+      },
+      "engines": {
+        "node": "^18.14.0 || ^20.0.0 || ^22.0.0 || >=24.0.0"
+      }
+    },
+    "node_modules/@types/jest/node_modules/picomatch": {
+      "version": "4.0.7",
+      "resolved": "https://registry.npmjs.org/picomatch/-/picomatch-4.0.7.tgz",
+      "integrity": "sha512-qcJu88Q2IWqJsDD529JKMdwGm/dvInW4HvQnRwiH9JtihJvzGOscDtHE3x1pBKeUOTysQ8kVmLnJ2kJu7yhcGA==",
+      "dev": true,
+      "license": "MIT",
+      "engines": {
+        "node": ">=12"
+      },
+      "funding": {
+        "url": "https://github.com/sponsors/jonschlinkert"
+      }
+    },
+    "node_modules/@types/jest/node_modules/pretty-format": {
+      "version": "30.5.1",
+      "resolved": "https://registry.npmjs.org/pretty-format/-/pretty-format-30.5.1.tgz",
+      "integrity": "sha512-byhRAPguVKMQIj4kjJwJ5lAskVhfuiSdiYl/aLTWpgkGEmic2jYhJh1yE9ih8Ox44Xg9ccCT11/S6QrzSJuNrg==",
+      "dev": true,
+      "license": "MIT",
+      "dependencies": {
+        "@jest/react-is-18": "npm:react-is@^18.3.1",
+        "@jest/react-is-19": "npm:react-is@^19.2.5",
+        "@jest/schemas": "30.5.0",
+        "ansi-styles": "^5.2.0"
+      },
+      "engines": {
+        "node": "^18.14.0 || ^20.0.0 || ^22.0.0 || >=24.0.0"
+      }
+    },
     "node_modules/@types/node": {
       "version": "22.7.5",
       "resolved": "https://registry.npmjs.org/@types/node/-/node-22.7.5.tgz",
@@ -3153,9 +3348,9 @@
       "license": "MIT"
     },
     "node_modules/picocolors": {
-      "version": "1.1.0",
-      "resolved": "https://registry.npmjs.org/picocolors/-/picocolors-1.1.0.tgz",
-      "integrity": "sha512-TQ92mBOW0l3LeMeyLV6mzy/kWr8lkd/hp3mTg7wYK7zJhuBStmGMBG0BdeDZS/dZx1IukaX6Bk11zcln25o1Aw==",
+      "version": "1.1.1",
+      "resolved": "https://registry.npmjs.org/picocolors/-/picocolors-1.1.1.tgz",
+      "integrity": "sha512-xceH2snhtb5M9liqDsmEw56le376mTZkEX/jEb/RxNFyegNul7eNslCXP9FDj/Lcu0X8KEyMceP2ntpaHrDEVA==",
       "dev": true,
       "license": "ISC"
     },
diff --git a/Sprint-2/package.json b/Sprint-2/package.json
index 80c16780f..9ed6915b3 100644
--- a/Sprint-2/package.json
+++ b/Sprint-2/package.json
@@ -10,6 +10,7 @@
   "author": "",
   "license": "ISC",
   "devDependencies": {
+    "@types/jest": "^30.0.0",
     "jest": "^29.7.0"
   }
 }

From a5c908d9de873d6951b1f15905b7bfd2dbce2d7c Mon Sep 17 00:00:00 2001
From: Aklilu Mihtsun <mihtsun.app@gmail.com>
Date: Tue, 10 Nov 2026 15:10:53 +0000
Subject: [PATCH 07/22] Remove unnecessary TypeScript reference from
 contains.test.js

---
 Sprint-2/implement/contains.test.js | 1 -
 1 file changed, 1 deletion(-)

diff --git a/Sprint-2/implement/contains.test.js b/Sprint-2/implement/contains.test.js
index 72864b82c..6fdaa9caf 100644
--- a/Sprint-2/implement/contains.test.js
+++ b/Sprint-2/implement/contains.test.js
@@ -1,5 +1,4 @@
 const contains = require("./contains.js");
-/// <reference types="jest" />
 
 /*
 Implement a function called contains that checks an object contains a

From 3a2f2132ca339361af1cc9b2601e258cdbba9b71 Mon Sep 17 00:00:00 2001
From: Aklilu Mihtsun <mihtsun.app@gmail.com>
Date: Tue, 10 Nov 2026 16:02:48 +0000
Subject: [PATCH 08/22] Refactor tests in lookup.test.js to validate
 createLookup function behavior and error handling

---
 Sprint-2/implement/lookup.test.js | 24 +++++++++++++++++++++++-
 1 file changed, 23 insertions(+), 1 deletion(-)

diff --git a/Sprint-2/implement/lookup.test.js b/Sprint-2/implement/lookup.test.js
index 547e06c5a..d0b561575 100644
--- a/Sprint-2/implement/lookup.test.js
+++ b/Sprint-2/implement/lookup.test.js
@@ -1,6 +1,28 @@
 const createLookup = require("./lookup.js");
 
-test.todo("creates a country currency code lookup for multiple codes");
+test("returns an object of country currency pair", () => {
+  expect(
+    createLookup([
+      ["US", "USD"],
+      ["CA", "CAD"],
+    ])
+  ).toEqual({ US: "USD", CA: "CAD" });
+});
+
+test("Throws an error if the input is not array of an array", () => {
+  expect(() => {
+    createLookup(["usd", "cad", "euro"]);
+  }).toThrow("createLookup requires array of an array");
+});
+
+test("Throws an error if the input is not array of an array with string elements", () => {
+  expect(() => {
+    createLookup([
+      [23, "USD"],
+      ["CA", 67],
+    ]);
+  }).toThrow("createLookup requires array of an array");
+});
 
 /*
 

From 4563f09c5a1948c84ed80aba1bbbe4e38bc18645 Mon Sep 17 00:00:00 2001
From: Aklilu Mihtsun <mihtsun.app@gmail.com>
Date: Tue, 10 Nov 2026 16:02:59 +0000
Subject: [PATCH 09/22] Implement createLookup function to transform
 country-currency pairs into an object

---
 Sprint-2/implement/lookup.js | 26 +++++++++++++++++++++++---
 1 file changed, 23 insertions(+), 3 deletions(-)

diff --git a/Sprint-2/implement/lookup.js b/Sprint-2/implement/lookup.js
index a6746e07f..47849dfdb 100644
--- a/Sprint-2/implement/lookup.js
+++ b/Sprint-2/implement/lookup.js
@@ -1,5 +1,25 @@
-function createLookup() {
-  // implementation here
-}
+function createLookup(countryCurrencyPairs) {
+  if (
+    !Array.isArray(countryCurrencyPairs) ||
+    !countryCurrencyPairs.every(
+      (item) =>
+        Array.isArray(item) &&
+        item.every((element) => typeof element === "string")
+    )
+  ) {
+    throw new Error("createLookup requires array of an array");
+  }
 
+  let currencyObject = {};
+  for (const arrayCurrency of countryCurrencyPairs) {
+    currencyObject[arrayCurrency[0]] = arrayCurrency[1];
+  }
+  return currencyObject;
+}
+/*console.log(
+  createLookup([
+    ["US", "USD"],
+    ["CA", "CAD"],
+  ])
+);*/
 module.exports = createLookup;

From 64405b5901574efde302319fba0883bb50a63f60 Mon Sep 17 00:00:00 2001
From: Aklilu Mihtsun <mihtsun.app@gmail.com>
Date: Wed, 11 Nov 2026 13:21:18 +0000
Subject: [PATCH 10/22] Implement tally function to count occurrences of items
 in an array

---
 Sprint-2/implement/tally.js | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/Sprint-2/implement/tally.js b/Sprint-2/implement/tally.js
index f47321812..116da3a24 100644
--- a/Sprint-2/implement/tally.js
+++ b/Sprint-2/implement/tally.js
@@ -1,3 +1,16 @@
-function tally() {}
+function tally(array) {
+  if (!Array.isArray(array)) {
+    throw new Error("tally requires an array");
+  }
+  objectItem = {};
+  for (const item of array) {
+    if (objectItem[item]) {
+      objectItem[item] = objectItem[item] + 1;
+    } else {
+      objectItem[item] = 1;
+    }
+  }
+  return objectItem;
+}
 
 module.exports = tally;

From c4e3c368e3485f97dd296c08e62bf9035f53123d Mon Sep 17 00:00:00 2001
From: Aklilu Mihtsun <mihtsun.app@gmail.com>
Date: Wed, 11 Nov 2026 13:21:27 +0000
Subject: [PATCH 11/22] Refactor tally tests to improve clarity and coverage

---
 Sprint-2/implement/tally.test.js | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/Sprint-2/implement/tally.test.js b/Sprint-2/implement/tally.test.js
index ca763c296..cea341aa8 100644
--- a/Sprint-2/implement/tally.test.js
+++ b/Sprint-2/implement/tally.test.js
@@ -19,16 +19,29 @@ const tally = require("./tally.js");
 // Given a function called tally
 // When passed an array of items
 // Then it should return an object containing the count for each unique item
+test("returns count for each unique item in the array", () => {
+  expect(tally(["a", "b", "b", "a", "c"])).toEqual({ a: 2, b: 2, c: 1 });
+});
 
 // 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("returns empty object for given empty array", () => {
+  expect(tally([])).toEqual({});
+});
 
 // Given an array with duplicate items
 // When passed to tally
 // Then it should return counts for each unique item
+test("returns count for each unique item in the array", () => {
+  expect(tally(["a", "b", 3, "a", "c"])).toEqual({ a: 2, b: 1, 3: 1, c: 1 });
+});
 
 // Given an invalid input like a string, a number, or no argument at all
 // When passed to tally
 // Then it should throw Error("tally requires an array")
+test("throws an error when not given an array", () => {
+  expect(() => {
+    tally("apple");
+  }).toThrow("tally requires an array");
+});

From 6a4db13af16e3ad204470972eedd41200b5a67c0 Mon Sep 17 00:00:00 2001
From: Aklilu Mihtsun <mihtsun.app@gmail.com>
Date: Wed, 11 Nov 2026 16:21:38 +0000
Subject: [PATCH 12/22] Refactor parseQueryString function to improve query
 parameter handling and readability

---
 Sprint-2/implement/querystring.js | 33 +++++++++++++++++++++++++++++--
 1 file changed, 31 insertions(+), 2 deletions(-)

diff --git a/Sprint-2/implement/querystring.js b/Sprint-2/implement/querystring.js
index 45ec4e5f3..08e36c122 100644
--- a/Sprint-2/implement/querystring.js
+++ b/Sprint-2/implement/querystring.js
@@ -3,11 +3,40 @@ function parseQueryString(queryString) {
   if (queryString.length === 0) {
     return queryParams;
   }
+  if (queryString.includes("%")) {
+    queryString = decodeURIComponent(queryString);
+  }
+  if (queryString.includes("+")) {
+    queryString = queryString.replaceAll("+", " ");
+  }
+  //const arrayValue = [];
+  let key = "";
+  let value = "";
+
   const keyValuePairs = queryString.split("&");
 
   for (const pair of keyValuePairs) {
-    const [key, value] = pair.split("=");
-    queryParams[key] = value;
+    if (pair.length === 0) {
+      continue;
+    }
+    const separatorIndex = pair.indexOf("=");
+    if (separatorIndex === 0) {
+      value = pair.slice(separatorIndex + 1);
+    } else if (separatorIndex === pair.length - 1) {
+      key = pair.slice(0, separatorIndex);
+    } else if (!pair.includes("=")) {
+      key = pair;
+    } else {
+      key = pair.slice(0, separatorIndex);
+      value = pair.slice(separatorIndex + 1);
+    }
+    if (!queryParams[key]) {
+      queryParams[key] = value;
+    } else if (Array.isArray(queryParams[key])) {
+      queryParams[key].push(value);
+    } else {
+      queryParams[key] = [queryParams[key], value];
+    }
   }
 
   return queryParams;

From 7aae0360852edbe6963d26e035c7633f515dc2e5 Mon Sep 17 00:00:00 2001
From: Aklilu Mihtsun <mihtsun.app@gmail.com>
Date: Wed, 11 Nov 2026 16:21:45 +0000
Subject: [PATCH 13/22] Fix syntax error in querystring.test.js by adding
 missing semicolon

---
 Sprint-2/implement/querystring.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Sprint-2/implement/querystring.test.js b/Sprint-2/implement/querystring.test.js
index 328b8df61..e9e0e9abd 100644
--- a/Sprint-2/implement/querystring.test.js
+++ b/Sprint-2/implement/querystring.test.js
@@ -3,7 +3,7 @@
 // Below are some test cases the implementation doesn't handle well.
 // Fix the implementation for these tests, 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("should parse values containing '='", () => {
   expect(parseQueryString("equation=a=b-2")).toEqual({

From dc40ffc7062695ad5c111c31b3f4eb36c96fa17f Mon Sep 17 00:00:00 2001
From: Aklilu Mihtsun <mihtsun.app@gmail.com>
Date: Wed, 11 Nov 2026 17:09:16 +0000
Subject: [PATCH 14/22] Fix invert function implementation to correctly swap
 keys and values in the object

---
 Sprint-2/interpret/invert.js | 17 ++++++++++++++++-
 1 file changed, 16 insertions(+), 1 deletion(-)

diff --git a/Sprint-2/interpret/invert.js b/Sprint-2/interpret/invert.js
index bb353fb1f..1216f000a 100644
--- a/Sprint-2/interpret/invert.js
+++ b/Sprint-2/interpret/invert.js
@@ -10,20 +10,35 @@ function invert(obj) {
   const invertedObj = {};
 
   for (const [key, value] of Object.entries(obj)) {
-    invertedObj.key = value;
+    invertedObj[value] = key;
   }
 
   return invertedObj;
 }
+//console.log(invert({ f: 34, h: 45, j: "rf" }));
+module.exports = invert;
 
 // a) What is the current return value when invert is called with { a : 1 }
 
+// ===> the current return value is { key: 1 }
+
 // b) What is the current return value when invert is called with { a: 1, b: 2 }
 
+// ===> the current return value is { key: 2 }
+
 // c) What is the target return value when invert is called with {a : 1, b: 2}
 
+// ===> the target return value is {"1": "a", "2": "b"}
+
 // c) What does Object.entries return? Why is it needed in this program?
 
+// ===> Object.entries return the key and value of an object, and in this program we used it to go through each key value pair and to put them in an array
+
 // d) Explain why the current return value is different from the target output
 
+// ===> first it used the dot notation instead of square bracket which is accessing the property using  a literal name
+// ===> second it is not inverted it still uses key value instead of value key so that it returns the inverted one
+
 // e) Fix the implementation of invert (and write tests to prove it's fixed!)
+
+// ===> I have fixed the program

From 2ebc9d0f79d063542d76bfb351c68d886a1d1e1b Mon Sep 17 00:00:00 2001
From: Aklilu Mihtsun <mihtsun.app@gmail.com>
Date: Wed, 11 Nov 2026 17:09:22 +0000
Subject: [PATCH 15/22] Add tests for invert function to verify key-value
 inversion

---
 Sprint-2/interpret/invert.test.js | 10 ++++++++++
 1 file changed, 10 insertions(+)
 create mode 100644 Sprint-2/interpret/invert.test.js

diff --git a/Sprint-2/interpret/invert.test.js b/Sprint-2/interpret/invert.test.js
new file mode 100644
index 000000000..ea41b0a4c
--- /dev/null
+++ b/Sprint-2/interpret/invert.test.js
@@ -0,0 +1,10 @@
+const invert = require("./invert.js");
+
+test("checking inversion ", () => {
+  expect(invert({ x: 10, y: 20 })).toEqual({ 10: "x", 20: "y" });
+  expect(invert({ f: 34, h: 45, j: "rf" })).toEqual({
+    34: "f",
+    45: "h",
+    rf: "j",
+  });
+});

From 69d91eef4d6c71f3fb1d70e34f35076b8990afed Mon Sep 17 00:00:00 2001
From: Aklilu Mihtsun <mihtsun.app@gmail.com>
Date: Thu, 12 Nov 2026 13:22:45 +0000
Subject: [PATCH 16/22] Fix author.js to correctly log property values instead
 of keys

---
 Sprint-2/debug/author.js | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/Sprint-2/debug/author.js b/Sprint-2/debug/author.js
index 46072c262..22a61dbf3 100644
--- a/Sprint-2/debug/author.js
+++ b/Sprint-2/debug/author.js
@@ -6,6 +6,9 @@
 // This program attempts to log out all the property values in the object.
 // But it isn't working. Explain why first and then fix the problem
 
+// when we run it, it logs out the property key instead of its value because for...in iterates over the property keys (names), not the property values.
+// we need to use square brackets [] to access the value associated with that property name
+
 const author = {
   firstName: "Zadie",
   lastName: "Smith",
@@ -15,5 +18,5 @@ const author = {
 };
 
 for (const value in author) {
-  console.log(value);
+  console.log(author[value]);
 }

From 7ee71050f4d75eaef4a6da96e3b4adef7c8ed7eb Mon Sep 17 00:00:00 2001
From: Aklilu Mihtsun <mihtsun.app@gmail.com>
Date: Thu, 12 Nov 2026 13:48:04 +0000
Subject: [PATCH 17/22] Refactor contains function to use Object.hasOwn for
 property checking

---
 Sprint-2/implement/contains.js | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/Sprint-2/implement/contains.js b/Sprint-2/implement/contains.js
index e2c7fe4d6..0a7a42895 100644
--- a/Sprint-2/implement/contains.js
+++ b/Sprint-2/implement/contains.js
@@ -2,11 +2,8 @@ function contains(object, name) {
   if (typeof object !== "object" || Array.isArray(object) || object === null) {
     throw new Error("contains requires an object");
   }
-
-  if (name in object) {
-    return true;
-  }
-  return false;
+  // the in Checks own and inherited properties so that is why it returned true when the name is 'toString'
+  return Object.hasOwn(object, name);
 }
-
+//console.log(contains({ a: 1 }, "toString"));
 module.exports = contains;

From 30f84035d3e12ae30cfd45f6a6eaf9fc2d61b9ac Mon Sep 17 00:00:00 2001
From: Aklilu Mihtsun <mihtsun.app@gmail.com>
Date: Thu, 12 Nov 2026 14:11:38 +0000
Subject: [PATCH 18/22] Refactor recipe.js to log ingredients in a single
 console statement

---
 Sprint-2/debug/recipe.js | 9 +++------
 1 file changed, 3 insertions(+), 6 deletions(-)

diff --git a/Sprint-2/debug/recipe.js b/Sprint-2/debug/recipe.js
index 07b11eeee..87f46278c 100644
--- a/Sprint-2/debug/recipe.js
+++ b/Sprint-2/debug/recipe.js
@@ -12,9 +12,6 @@ const recipe = {
   serves: 2,
   ingredients: ["olive oil", "tomatoes", "salt", "pepper"],
 };
-
-for (const cookingIngredients of recipe.ingredients) {
-  console.log(cookingIngredients);
-}
-
-console.log(`${recipe.title} serves ${recipe.serves}`);
+console.log(
+  recipe.title + " serves " + recipe.serves + recipe.ingredients.join("\n")
+);

From 1d3281e351545f3d14b6389ece3e041f88fe9b4d Mon Sep 17 00:00:00 2001
From: Aklilu Mihtsun <mihtsun.app@gmail.com>
Date: Thu, 12 Nov 2026 15:35:19 +0000
Subject: [PATCH 19/22] Refactor createLookup function to improve input
 validation and error handling

---
 Sprint-2/implement/lookup.js | 27 ++++++++++++---------------
 1 file changed, 12 insertions(+), 15 deletions(-)

diff --git a/Sprint-2/implement/lookup.js b/Sprint-2/implement/lookup.js
index 47849dfdb..3d1f21bfa 100644
--- a/Sprint-2/implement/lookup.js
+++ b/Sprint-2/implement/lookup.js
@@ -1,13 +1,15 @@
 function createLookup(countryCurrencyPairs) {
-  if (
-    !Array.isArray(countryCurrencyPairs) ||
-    !countryCurrencyPairs.every(
-      (item) =>
-        Array.isArray(item) &&
-        item.every((element) => typeof element === "string")
-    )
-  ) {
-    throw new Error("createLookup requires array of an array");
+  if (!Array.isArray(countryCurrencyPairs)) {
+    throw new Error("createLookup requires an array");
+  }
+  for (const keyVlauePairs of countryCurrencyPairs) {
+    if (!Array.isArray(keyVlauePairs)) {
+      throw new Error("createLookup requires an array of key value pair");
+    } else if (keyVlauePairs.length !== 2) {
+      throw new Error("createLookup requires key value pair");
+    } else if (keyVlauePairs.some((element) => typeof element !== "string")) {
+      throw new Error("createLookup requires a string of key value pair");
+    }
   }
 
   let currencyObject = {};
@@ -16,10 +18,5 @@ function createLookup(countryCurrencyPairs) {
   }
   return currencyObject;
 }
-/*console.log(
-  createLookup([
-    ["US", "USD"],
-    ["CA", "CAD"],
-  ])
-);*/
+
 module.exports = createLookup;

From 32d131409b43cf3e18d67cd1a17b8558f3f0f62d Mon Sep 17 00:00:00 2001
From: Aklilu Mihtsun <mihtsun.app@gmail.com>
Date: Thu, 12 Nov 2026 15:35:25 +0000
Subject: [PATCH 20/22] Refactor tests in lookup.test.js for clarity and
 accuracy in error messages

---
 Sprint-2/implement/lookup.test.js | 17 +++++++++++++----
 1 file changed, 13 insertions(+), 4 deletions(-)

diff --git a/Sprint-2/implement/lookup.test.js b/Sprint-2/implement/lookup.test.js
index d0b561575..4798967f6 100644
--- a/Sprint-2/implement/lookup.test.js
+++ b/Sprint-2/implement/lookup.test.js
@@ -9,19 +9,28 @@ test("returns an object of country currency pair", () => {
   ).toEqual({ US: "USD", CA: "CAD" });
 });
 
-test("Throws an error if the input is not array of an array", () => {
+test("Throws an error when there are more strings than key value pairs", () => {
+  expect(() => {
+    createLookup([
+      ["US", "USD", "EURO"],
+      ["CA", "CAD"],
+    ]);
+  }).toThrow("createLookup requires key value pair");
+});
+
+test("Throws an error if the input is not an array", () => {
   expect(() => {
     createLookup(["usd", "cad", "euro"]);
-  }).toThrow("createLookup requires array of an array");
+  }).toThrow("createLookup requires an array");
 });
 
-test("Throws an error if the input is not array of an array with string elements", () => {
+test("Throws an error if an array has elements that are not string key value pairs", () => {
   expect(() => {
     createLookup([
       [23, "USD"],
       ["CA", 67],
     ]);
-  }).toThrow("createLookup requires array of an array");
+  }).toThrow("createLookup requires a string of key value pair");
 });
 
 /*

From fba5a724744e37ea45f603b840071f4c8f42fb36 Mon Sep 17 00:00:00 2001
From: Aklilu Mihtsun <mihtsun.app@gmail.com>
Date: Thu, 12 Nov 2026 15:42:40 +0000
Subject: [PATCH 21/22] Update test descriptions in tally.test.js for clarity
 and accuracy

---
 Sprint-2/implement/tally.test.js | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/Sprint-2/implement/tally.test.js b/Sprint-2/implement/tally.test.js
index cea341aa8..6a982f377 100644
--- a/Sprint-2/implement/tally.test.js
+++ b/Sprint-2/implement/tally.test.js
@@ -33,7 +33,7 @@ test("returns empty object for given empty array", () => {
 // Given an array with duplicate items
 // When passed to tally
 // Then it should return counts for each unique item
-test("returns count for each unique item in the array", () => {
+test("returns count for each unique item with different type in the array", () => {
   expect(tally(["a", "b", 3, "a", "c"])).toEqual({ a: 2, b: 1, 3: 1, c: 1 });
 });
 
@@ -44,4 +44,12 @@ test("throws an error when not given an array", () => {
   expect(() => {
     tally("apple");
   }).toThrow("tally requires an array");
+
+  expect(() => {
+    tally(234);
+  }).toThrow("tally requires an array");
+
+  expect(() => {
+    tally();
+  }).toThrow("tally requires an array");
 });

From fae81859573692fc87ea50cfacede22668f1a2f4 Mon Sep 17 00:00:00 2001
From: Aklilu Mihtsun <mihtsun.app@gmail.com>
Date: Thu, 12 Nov 2026 15:43:00 +0000
Subject: [PATCH 22/22] Fix variable declaration in tally function to use const
 for objectItem

---
 Sprint-2/implement/tally.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Sprint-2/implement/tally.js b/Sprint-2/implement/tally.js
index 116da3a24..189e186f7 100644
--- a/Sprint-2/implement/tally.js
+++ b/Sprint-2/implement/tally.js
@@ -2,7 +2,7 @@ function tally(array) {
   if (!Array.isArray(array)) {
     throw new Error("tally requires an array");
   }
-  objectItem = {};
+  const objectItem = {};
   for (const item of array) {
     if (objectItem[item]) {
       objectItem[item] = objectItem[item] + 1;