From ca2ad9f5d8c6013ed5ec37e9fd4e4ddd3acab311 Mon Sep 17 00:00:00 2001
From: joanne342 <130585013+joanne342@users.noreply.github.com>
Date: Thu, 9 Jul 2026 09:10:11 +0100
Subject: [PATCH 01/19] Update address.js

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

diff --git a/Sprint-2/debug/address.js b/Sprint-2/debug/address.js
index 940a6af83..fde180d6d 100644
--- a/Sprint-2/debug/address.js
+++ b/Sprint-2/debug/address.js
@@ -12,4 +12,4 @@ const address = {
   postcode: "XYZ 123",
 };
 
-console.log(`My house number is ${address[0]}`);
+console.log(`My house number is ${address["houseNumber"]}`);

From 4048bc9a3e39bd14f2082714ed34b692566bc0af Mon Sep 17 00:00:00 2001
From: joanne342 <130585013+joanne342@users.noreply.github.com>
Date: Thu, 9 Jul 2026 11:03:23 +0100
Subject: [PATCH 02/19] Update author.js

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

diff --git a/Sprint-2/debug/author.js b/Sprint-2/debug/author.js
index 8c2125977..7ba8f4c75 100644
--- a/Sprint-2/debug/author.js
+++ b/Sprint-2/debug/author.js
@@ -11,6 +11,6 @@ const author = {
   alive: true,
 };
 
-for (const value of author) {
+for (const value of Object.values(author)) {
   console.log(value);
 }

From d91daaa454b0bcf4f2ecbd497e0311f32818fa6a Mon Sep 17 00:00:00 2001
From: joanne342 <130585013+joanne342@users.noreply.github.com>
Date: Thu, 9 Jul 2026 11:07:46 +0100
Subject: [PATCH 03/19] Update recipe.js

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

diff --git a/Sprint-2/debug/recipe.js b/Sprint-2/debug/recipe.js
index 6cbdd22cd..a413b3332 100644
--- a/Sprint-2/debug/recipe.js
+++ b/Sprint-2/debug/recipe.js
@@ -12,4 +12,4 @@ const recipe = {
 
 console.log(`${recipe.title} serves ${recipe.serves}
   ingredients:
-${recipe}`);
+${recipe.ingredients.join("\n")}`);

From cc230d3ad5f601a48f00e1cf59e27f679ff916e9 Mon Sep 17 00:00:00 2001
From: joanne342 <130585013+joanne342@users.noreply.github.com>
Date: Thu, 9 Jul 2026 11:16:53 +0100
Subject: [PATCH 04/19] Update contains.test.js

---
 Sprint-2/implement/contains.test.js | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/Sprint-2/implement/contains.test.js b/Sprint-2/implement/contains.test.js
index 326bdb1f2..aa1f35ebe 100644
--- a/Sprint-2/implement/contains.test.js
+++ b/Sprint-2/implement/contains.test.js
@@ -20,16 +20,28 @@ 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("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("returns true when object contains an existing property", () => {
+  expect(contains({ a: 1, b: 2 }, "a")).toBe(true);
+});
 
 // Given an object with properties
 // When passed to contains with a non-existent property name
 // Then it should return false
+test("returns false when object does not contain the property", () => {
+  expect(contains({ a: 1, b: 2 }, "c")).toBe(false);
+});
 
 // Given invalid parameters like an array
 // When passed to contains
 // Then it should return false or throw an error
+test("returns false or throws an error when passed invalid parameters like an array", () => {
+  expect(() => contains([], "a")).not.toThrow();
+  expect(contains([], "a")).toBe(false);
+});

From 5325eb452b982d4f1083f438e1bd918fb5ce273f Mon Sep 17 00:00:00 2001
From: joanne342 <130585013+joanne342@users.noreply.github.com>
Date: Thu, 9 Jul 2026 11:21:59 +0100
Subject: [PATCH 05/19] Update contains.js

---
 Sprint-2/implement/contains.js | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/Sprint-2/implement/contains.js b/Sprint-2/implement/contains.js
index cd779308a..51063ecd2 100644
--- a/Sprint-2/implement/contains.js
+++ b/Sprint-2/implement/contains.js
@@ -1,3 +1,5 @@
-function contains() {}
+function contains() {
+  return property_name in obj;
+}
 
 module.exports = contains;

From 8ed4137b6e3652cc943b8270942d554835cc338b Mon Sep 17 00:00:00 2001
From: joanne342 <130585013+joanne342@users.noreply.github.com>
Date: Thu, 9 Jul 2026 11:31:17 +0100
Subject: [PATCH 06/19] Update lookup.test.js

---
 Sprint-2/implement/lookup.test.js | 34 +++++++++++++++++++++++++++++++
 1 file changed, 34 insertions(+)

diff --git a/Sprint-2/implement/lookup.test.js b/Sprint-2/implement/lookup.test.js
index 547e06c5a..3bb11ac1d 100644
--- a/Sprint-2/implement/lookup.test.js
+++ b/Sprint-2/implement/lookup.test.js
@@ -33,3 +33,37 @@ It should return:
    'CA': 'CAD'
  }
 */
+
+test("creates a country currency code lookup for multiple codes", () => {
+  const countryCurrencyPairs = [
+    ["US", "USD"],
+    ["CA", "CAD"],
+  ];
+
+  const result = createLookup(countryCurrencyPairs);
+
+  expect(result).toEqual({
+    US: "USD",
+    CA: "CAD",
+  });
+});
+
+test("creates a country currency code lookup for a single code", () => {
+  const countryCurrencyPairs = [
+    ["GB", "GBP"],
+  ];
+
+  const result = createLookup(countryCurrencyPairs);
+
+  expect(result).toEqual({
+    GB: "GBP",
+  });
+});
+
+test("returns an empty object when given an empty array", () => {
+  const countryCurrencyPairs = [];
+
+  const result = createLookup(countryCurrencyPairs);
+
+  expect(result).toEqual({});
+});

From caa36799abf08c4e22526b6d2ddf08e800721b68 Mon Sep 17 00:00:00 2001
From: joanne342 <130585013+joanne342@users.noreply.github.com>
Date: Thu, 9 Jul 2026 11:38:34 +0100
Subject: [PATCH 07/19] Update lookup.js

---
 Sprint-2/implement/lookup.js | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/Sprint-2/implement/lookup.js b/Sprint-2/implement/lookup.js
index a6746e07f..6929ca228 100644
--- a/Sprint-2/implement/lookup.js
+++ b/Sprint-2/implement/lookup.js
@@ -1,5 +1,10 @@
 function createLookup() {
   // implementation here
+      for (const [country, currency] of country_currency_pairs) {
+        lookup[country] = currency;
+    }
+
+    return lookup;
 }
 
 module.exports = createLookup;

From 06a8a411e14b0e8d1d1b354ab18b33561ce36e99 Mon Sep 17 00:00:00 2001
From: joanne342 <130585013+joanne342@users.noreply.github.com>
Date: Thu, 9 Jul 2026 13:20:31 +0100
Subject: [PATCH 08/19] Update querystring.test.js

---
 Sprint-2/implement/querystring.test.js | 62 +++++++++++++++++++++++---
 1 file changed, 56 insertions(+), 6 deletions(-)

diff --git a/Sprint-2/implement/querystring.test.js b/Sprint-2/implement/querystring.test.js
index 328b8df61..909f04abc 100644
--- a/Sprint-2/implement/querystring.test.js
+++ b/Sprint-2/implement/querystring.test.js
@@ -37,12 +37,62 @@ test("should replace '+' by ' '", () => {
   });
 });
 
-// Stretch exercise: Handling query strings that contain identical keys
+test("should parse basic key-value pairs", () => {
+  expect(parseQueryString("name=John&age=30")).toEqual({
+    name: "John",
+    age: "30",
+  });
+});
+
+test("should replace '+' by ' '", () => {
+  expect(parseQueryString("name=John+Doe&city=New+York")).toEqual({
+    name: "John Doe",
+    city: "New York",
+  });
+
+  expect(parseQueryString("full+name=John+Doe")).toEqual({
+    "full name": "John Doe",
+  });
+});
+
+test("should decode percent-encoded characters", () => {
+  expect(parseQueryString("message=Hello%20World")).toEqual({
+    message: "Hello World",
+  });
 
-// Delete this test if you are not working on this optional case
-test("should store values of a key in an array when the key has 2 or more values", () => {
-  expect(parseQueryString("key=value1&key=value2&key=value3&foo=bar")).toEqual({
-    key: ["value1", "value2", "value3"],
-    foo: "bar",
+  expect(parseQueryString("%24half=1%2F2")).toEqual({
+    $half: "1/2",
   });
 });
+
+test("should handle keys without values", () => {
+  expect(parseQueryString("debug")).toEqual({
+    debug: "",
+  });
+
+  expect(parseQueryString("key")).toEqual({
+    key: "",
+  });
+});
+
+test("should handle empty values", () => {
+  expect(parseQueryString("name=&age=25")).toEqual({
+    name: "",
+    age: "25",
+  });
+
+  expect(parseQueryString("key=")).toEqual({
+    key: "",
+  });
+});
+
+test("should return empty object for empty input", () => {
+  expect(parseQueryString("")).toEqual({});
+});
+
+test("should use the last value when duplicate keys exist", () => {
+  expect(parseQueryString("color=red&color=blue")).toEqual({
+    color: "blue",
+  });
+});
+

From 0eed554d3306314cfe89708e811b952adc747e96 Mon Sep 17 00:00:00 2001
From: joanne342 <130585013+joanne342@users.noreply.github.com>
Date: Thu, 9 Jul 2026 13:22:25 +0100
Subject: [PATCH 09/19] Update querystring.js

---
 Sprint-2/implement/querystring.js | 36 +++++++++++++++++++++++--------
 1 file changed, 27 insertions(+), 9 deletions(-)

diff --git a/Sprint-2/implement/querystring.js b/Sprint-2/implement/querystring.js
index 45ec4e5f3..54eb8ea5a 100644
--- a/Sprint-2/implement/querystring.js
+++ b/Sprint-2/implement/querystring.js
@@ -1,16 +1,34 @@
 function parseQueryString(queryString) {
-  const queryParams = {};
-  if (queryString.length === 0) {
-    return queryParams;
-  }
-  const keyValuePairs = queryString.split("&");
+  if (queryString === "") {
+    return {};
+  } else {
+    queryString = decodeURIComponent(queryString)
+      .replace(/\+/g, " ")
+      .replace(/&&/g, "&")
+      .replace(/&+$/, "");
+
+    const splitByAnds = queryString.split("&");
+
+    const splitByEquals = splitByAnds.map(x => {
+      const parts = x.split("=", 2);
+      return parts.length === 1 ? [parts[0], ""] : parts;
+    });
 
-  for (const pair of keyValuePairs) {
-    const [key, value] = pair.split("=");
-    queryParams[key] = value;
+    return Object.fromEntries(splitByEquals);
   }
+}
+  // const queryParams = {};
+  // if (queryString.length === 0) {
+  //   return queryParams;
+  // }
+  // const keyValuePairs = queryString.split("&");
+
+  // for (const pair of keyValuePairs) {
+  //   const [key, value] = pair.split("=");
+  //   queryParams[key] = value;
+  // }
 
-  return queryParams;
+  // return queryParams;
 }
 
 module.exports = parseQueryString;

From c5fc82b325cd92b945677fbe476f8de0a573f512 Mon Sep 17 00:00:00 2001
From: joanne342 <130585013+joanne342@users.noreply.github.com>
Date: Thu, 9 Jul 2026 13:56:55 +0100
Subject: [PATCH 10/19] Update contains.js

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

diff --git a/Sprint-2/implement/contains.js b/Sprint-2/implement/contains.js
index 51063ecd2..cf2d0757a 100644
--- a/Sprint-2/implement/contains.js
+++ b/Sprint-2/implement/contains.js
@@ -1,4 +1,4 @@
-function contains() {
+function contains(obj, property_name) {
   return property_name in obj;
 }
 

From 32a8ef2010eb3fbcd4c6d04428e51cdf96f54193 Mon Sep 17 00:00:00 2001
From: joanne342 <130585013+joanne342@users.noreply.github.com>
Date: Thu, 9 Jul 2026 14:03:25 +0100
Subject: [PATCH 11/19] Update lookup.js

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

diff --git a/Sprint-2/implement/lookup.js b/Sprint-2/implement/lookup.js
index 6929ca228..4373213ac 100644
--- a/Sprint-2/implement/lookup.js
+++ b/Sprint-2/implement/lookup.js
@@ -1,5 +1,6 @@
-function createLookup() {
+function createLookup(country_currency_pairs) {
   // implementation here
+      const lookup = {};
       for (const [country, currency] of country_currency_pairs) {
         lookup[country] = currency;
     }

From 47caa8c2ebf6fc99e7c761bb81c214d372c59683 Mon Sep 17 00:00:00 2001
From: joanne342 <130585013+joanne342@users.noreply.github.com>
Date: Thu, 9 Jul 2026 14:04:08 +0100
Subject: [PATCH 12/19] Update lookup.test.js

---
 Sprint-2/implement/lookup.test.js | 2 --
 1 file changed, 2 deletions(-)

diff --git a/Sprint-2/implement/lookup.test.js b/Sprint-2/implement/lookup.test.js
index 3bb11ac1d..beb33b5b3 100644
--- a/Sprint-2/implement/lookup.test.js
+++ b/Sprint-2/implement/lookup.test.js
@@ -1,7 +1,5 @@
 const createLookup = require("./lookup.js");
 
-test.todo("creates a country currency code lookup for multiple codes");
-
 /*
 
 Create a lookup object of key value pairs from an array of code pairs

From a0c43293b33e90b3e0d91f0fa35d2cf591b79394 Mon Sep 17 00:00:00 2001
From: joanne342 <130585013+joanne342@users.noreply.github.com>
Date: Thu, 9 Jul 2026 14:06:23 +0100
Subject: [PATCH 13/19] Update querystring.js

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

diff --git a/Sprint-2/implement/querystring.js b/Sprint-2/implement/querystring.js
index 54eb8ea5a..6d04c413d 100644
--- a/Sprint-2/implement/querystring.js
+++ b/Sprint-2/implement/querystring.js
@@ -29,6 +29,6 @@ function parseQueryString(queryString) {
   // }
 
   // return queryParams;
-}
+
 
 module.exports = parseQueryString;

From 896e52b8ecbe2ae6b6ba3938058097b360918bc9 Mon Sep 17 00:00:00 2001
From: joanne342 <130585013+joanne342@users.noreply.github.com>
Date: Thu, 9 Jul 2026 14:46:10 +0100
Subject: [PATCH 14/19] Update querystring.js

---
 Sprint-2/implement/querystring.js | 21 ++++++---------------
 1 file changed, 6 insertions(+), 15 deletions(-)

diff --git a/Sprint-2/implement/querystring.js b/Sprint-2/implement/querystring.js
index 6d04c413d..c825d8cef 100644
--- a/Sprint-2/implement/querystring.js
+++ b/Sprint-2/implement/querystring.js
@@ -10,25 +10,16 @@ function parseQueryString(queryString) {
     const splitByAnds = queryString.split("&");
 
     const splitByEquals = splitByAnds.map(x => {
-      const parts = x.split("=", 2);
-      return parts.length === 1 ? [parts[0], ""] : parts;
+      const match = x.match(/^([^=]*)(?:=(.*))?$/);
+
+      const key = match[1];
+      const value = match[2] ?? "";
+
+      return [key, value];
     });
 
     return Object.fromEntries(splitByEquals);
   }
 }
-  // const queryParams = {};
-  // if (queryString.length === 0) {
-  //   return queryParams;
-  // }
-  // const keyValuePairs = queryString.split("&");
-
-  // for (const pair of keyValuePairs) {
-  //   const [key, value] = pair.split("=");
-  //   queryParams[key] = value;
-  // }
-
-  // return queryParams;
-
 
 module.exports = parseQueryString;

From f8ce3aaddb9abfd008fcc8efc701101e6892fc2d Mon Sep 17 00:00:00 2001
From: joanne342 <130585013+joanne342@users.noreply.github.com>
Date: Thu, 9 Jul 2026 15:07:55 +0100
Subject: [PATCH 15/19] Update tally.test.js

---
 Sprint-2/implement/tally.test.js | 23 ++++++++++++++++++++++-
 1 file changed, 22 insertions(+), 1 deletion(-)

diff --git a/Sprint-2/implement/tally.test.js b/Sprint-2/implement/tally.test.js
index 2ceffa8dd..ea349000e 100644
--- a/Sprint-2/implement/tally.test.js
+++ b/Sprint-2/implement/tally.test.js
@@ -20,15 +20,36 @@ const tally = require("./tally.js");
 // When passed an array of items
 // Then it should return an object containing the count for each unique item
 
+test("tally counts the frequency of each unique item", () => {
+  expect(tally(["a", "a", "b", "c"])).toEqual({
+    a: 2,
+    b: 1,
+    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("tally on an empty array returns an empty object", () => {
+  expect(tally([])).toEqual({});
+});
 
 // Given an array with duplicate items
 // When passed to tally
 // Then it should return counts for each unique item
 
+test("tally counts duplicate items correctly", () => {
+  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("tally throws an error when passed invalid input", () => {
+  expect(() => tally("a")).toThrow();
+});

From aaeb462d2a39f408a22f8313ffc0ae147e72cedb Mon Sep 17 00:00:00 2001
From: joanne342 <130585013+joanne342@users.noreply.github.com>
Date: Thu, 9 Jul 2026 15:27:05 +0100
Subject: [PATCH 16/19] Update tally.js

---
 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..84b03e706 100644
--- a/Sprint-2/implement/tally.js
+++ b/Sprint-2/implement/tally.js
@@ -1,3 +1,16 @@
-function tally() {}
+function tally(items) {
+  if (!Array.isArray(items)) {
+    throw new TypeError("Input must be an array");
+  }
+
+  const uniqueItems = [...new Set(items)].sort();
+
+  const counts = {};
+  for (const item of uniqueItems) {
+    counts[item] = items.filter(x => x === item).length;
+  }
+
+  return counts;
+}
 
 module.exports = tally;

From 99d8442a0b14f53c07ce5b5bae3304675cdd6c7c Mon Sep 17 00:00:00 2001
From: joanne342 <130585013+joanne342@users.noreply.github.com>
Date: Fri, 10 Jul 2026 08:06:59 +0100
Subject: [PATCH 17/19] Update invert.js

---
 Sprint-2/interpret/invert.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/Sprint-2/interpret/invert.js b/Sprint-2/interpret/invert.js
index bb353fb1f..f04b2fb08 100644
--- a/Sprint-2/interpret/invert.js
+++ b/Sprint-2/interpret/invert.js
@@ -9,8 +9,8 @@
 function invert(obj) {
   const invertedObj = {};
 
-  for (const [key, value] of Object.entries(obj)) {
-    invertedObj.key = value;
+  for (const [value, key] of Object.entries(obj)) {
+    invertedObj[key] = value;
   }
 
   return invertedObj;

From ca1fe4e533070f77a568ce3c3c17d96503ecc13f Mon Sep 17 00:00:00 2001
From: joanne342 <130585013+joanne342@users.noreply.github.com>
Date: Fri, 10 Jul 2026 08:13:15 +0100
Subject: [PATCH 18/19] Create invert.test.js

---
 Sprint-2/interpret/invert.test.js | 1 +
 1 file changed, 1 insertion(+)
 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..8b1378917
--- /dev/null
+++ b/Sprint-2/interpret/invert.test.js
@@ -0,0 +1 @@
+

From 13a400e9ff4ff3bbf55749768586dcd924333442 Mon Sep 17 00:00:00 2001
From: joanne342 <130585013+joanne342@users.noreply.github.com>
Date: Fri, 10 Jul 2026 08:14:17 +0100
Subject: [PATCH 19/19] Update invert.test.js

---
 Sprint-2/interpret/invert.test.js | 45 +++++++++++++++++++++++++++++++
 1 file changed, 45 insertions(+)

diff --git a/Sprint-2/interpret/invert.test.js b/Sprint-2/interpret/invert.test.js
index 8b1378917..fd92c1baf 100644
--- a/Sprint-2/interpret/invert.test.js
+++ b/Sprint-2/interpret/invert.test.js
@@ -1 +1,46 @@
+const invert = require("./invert.js");
 
+/*
+Implement a function called invert that swaps the keys and values of an object.
+
+E.g. invert({ x: 10, y: 20 })
+// returns { "10": "x", "20": "y" }
+*/
+
+// Acceptance criteria:
+
+// Given an empty object
+// When passed to invert
+// Then it should return an empty object
+test("returns an empty object when given an empty object", () => {
+  expect(invert({})).toEqual({});
+});
+
+// Given an object with one property
+// When passed to invert
+// Then it should swap the key and value
+test("inverts an object with one key-value pair", () => {
+  expect(invert({ a: 1 })).toEqual({
+    "1": "a",
+  });
+});
+
+// Given an object with multiple properties
+// When passed to invert
+// Then it should swap all keys and values
+test("inverts an object with multiple key-value pairs", () => {
+  expect(invert({ a: 1, b: 2 })).toEqual({
+    "1": "a",
+    "2": "b",
+  });
+});
+
+// Given an object with string values
+// When passed to invert
+// Then it should swap the keys and values
+test("inverts string values correctly", () => {
+  expect(invert({ first: "apple", second: "banana" })).toEqual({
+    apple: "first",
+    banana: "second",
+  });
+});