From 3423b3d6fbce5decc6da366c3498b0dfc66bef7d Mon Sep 17 00:00:00 2001
From: jamesishimwe <james123ishimwe@gmail.com>
Date: Fri, 10 Apr 2026 19:20:31 +0200
Subject: [PATCH 01/28] Fix the code in the log on how to get dictionary value

---
 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..f28985431 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}`);
\ No newline at end of file

From 8ea5df9fbea73d7560ed7f3572f7d96184c75d8c Mon Sep 17 00:00:00 2001
From: jamesishimwe <james123ishimwe@gmail.com>
Date: Fri, 10 Apr 2026 20:02:08 +0200
Subject: [PATCH 02/28] Fix the code for iterating dictionary

---
 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 1030df2f0a08e9e4828ddeeef34f7c2f37748763 Mon Sep 17 00:00:00 2001
From: jamesishimwe <james123ishimwe@gmail.com>
Date: Fri, 10 Apr 2026 20:12:00 +0200
Subject: [PATCH 03/28] Fix the code to get ingredients from recipe to
 recipe.ingredient

---
 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..d0b246f22 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}`);

From b05607426dfe1708567425b1a3cfe6f4f67d98e9 Mon Sep 17 00:00:00 2001
From: jamesishimwe <james123ishimwe@gmail.com>
Date: Fri, 10 Apr 2026 20:29:08 +0200
Subject: [PATCH 04/28] Implement the function contains

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

diff --git a/Sprint-2/implement/contains.js b/Sprint-2/implement/contains.js
index cd779308a..bd1be68b4 100644
--- a/Sprint-2/implement/contains.js
+++ b/Sprint-2/implement/contains.js
@@ -1,3 +1,6 @@
-function contains() {}
+function contains(Obj,key) {
+    if(Obj === null || typeof Obj !== "object" || Array.isArray(Obj)) return false;
+     return Object.prototype.hasOwnProperty.call(Obj, key);
+}
 
 module.exports = contains;

From dd0f4aa5b135d24f3a292e3ddfc24b01fd7272b7 Mon Sep 17 00:00:00 2001
From: jamesishimwe <james123ishimwe@gmail.com>
Date: Fri, 10 Apr 2026 23:37:16 +0200
Subject: [PATCH 05/28] Write tests for  contains function

---
 Sprint-2/implement/contains.test.js | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/Sprint-2/implement/contains.test.js b/Sprint-2/implement/contains.test.js
index 326bdb1f2..a631e6414 100644
--- a/Sprint-2/implement/contains.test.js
+++ b/Sprint-2/implement/contains.test.js
@@ -33,3 +33,19 @@ test.todo("contains on empty object returns false");
 // Given invalid parameters like an array
 // When passed to contains
 // Then it should return false or throw an error
+
+test("contains on empty object returns false", () => {
+  expect(contains({}, "a")).toEqual(false);
+});
+
+test("returns true when property exists", () => {
+  expect(contains({ a: 1, b: 2 }, "a")).toEqual(true);
+});
+
+test("returns false when property does not exist", () => {
+  expect(contains({ a: 1, b: 2 }, "c")).toEqual(false);
+});
+
+test("returns false for invalid input like array", () => {
+  expect(contains([1, 2, 3], "0")).toEqual(false);
+});
\ No newline at end of file

From 3926858fe68b086ea6ddbb70a7bde41a1804c704 Mon Sep 17 00:00:00 2001
From: jamesishimwe <james123ishimwe@gmail.com>
Date: Sat, 11 Apr 2026 11:47:11 +0200
Subject: [PATCH 06/28] Implement function createLookUp

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

diff --git a/Sprint-2/implement/lookup.js b/Sprint-2/implement/lookup.js
index a6746e07f..6c2466437 100644
--- a/Sprint-2/implement/lookup.js
+++ b/Sprint-2/implement/lookup.js
@@ -1,5 +1,5 @@
-function createLookup() {
-  // implementation here
+function createLookup(countryCurrencyPairs) {
+return Object.fromEntries(countryCurrencyPairs);
 }
 
 module.exports = createLookup;

From cb7f840de05ebba8e039cf8b095999f8eb6b6155 Mon Sep 17 00:00:00 2001
From: jamesishimwe <james123ishimwe@gmail.com>
Date: Sat, 11 Apr 2026 11:59:29 +0200
Subject: [PATCH 07/28] Add test for undefined array

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

diff --git a/Sprint-2/implement/lookup.js b/Sprint-2/implement/lookup.js
index 6c2466437..1839a7455 100644
--- a/Sprint-2/implement/lookup.js
+++ b/Sprint-2/implement/lookup.js
@@ -1,4 +1,7 @@
 function createLookup(countryCurrencyPairs) {
+   if (!Array.isArray(countryCurrencyPairs)) {
+    return {};
+  }
 return Object.fromEntries(countryCurrencyPairs);
 }
 

From 126e361e1a4ecca4b0a90c8a6f1c906af166a4ea Mon Sep 17 00:00:00 2001
From: jamesishimwe <james123ishimwe@gmail.com>
Date: Sat, 11 Apr 2026 11:59:52 +0200
Subject: [PATCH 08/28] Write tests for lookup function

---
 Sprint-2/implement/lookup.test.js | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/Sprint-2/implement/lookup.test.js b/Sprint-2/implement/lookup.test.js
index 547e06c5a..a27e6ba44 100644
--- a/Sprint-2/implement/lookup.test.js
+++ b/Sprint-2/implement/lookup.test.js
@@ -33,3 +33,31 @@ It should return:
    'CA': 'CAD'
  }
 */
+
+
+test("returns empty object for empty array", () => {
+  expect(createLookup([])).toEqual({});
+});
+
+test("creates lookup from country-currency pairs", () => {
+  expect(createLookup([['US', 'USD'], ['CA', 'CAD']])).toEqual({
+    US: 'USD',
+    CA: 'CAD',
+  });
+});
+
+test("handles single pair", () => {
+  expect(createLookup([['JP', 'JPY']])).toEqual({
+    JP: 'JPY',
+  });
+});
+
+test("overwrites duplicate country codes (last one wins)", () => {
+  expect(createLookup([['US', 'USD'], ['US', 'USN']])).toEqual({
+    US: 'USN',
+  });
+});
+
+test("handles invalid input (non-array)", () => {
+  expect(createLookup(null)).toEqual({});
+});
\ No newline at end of file

From 35fb86ce036ee5865a8a3f2e48fa04f2fb5bfc72 Mon Sep 17 00:00:00 2001
From: jamesishimwe <james123ishimwe@gmail.com>
Date: Fri, 1 May 2026 09:17:05 +0200
Subject: [PATCH 09/28] Fix the code for queryString

---
 Sprint-2/implement/querystring.js | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/Sprint-2/implement/querystring.js b/Sprint-2/implement/querystring.js
index 45ec4e5f3..1dc051774 100644
--- a/Sprint-2/implement/querystring.js
+++ b/Sprint-2/implement/querystring.js
@@ -6,11 +6,12 @@ function parseQueryString(queryString) {
   const keyValuePairs = queryString.split("&");
 
   for (const pair of keyValuePairs) {
-    const [key, value] = pair.split("=");
+    var [key, ...value] = pair.split("=");
+    value = value.join("=");
     queryParams[key] = value;
   }
 
   return queryParams;
 }
-
+parseQueryString("equation=x=y+1");
 module.exports = parseQueryString;

From baf9e28c8d250a54e1f12e5b874fa7d48f644924 Mon Sep 17 00:00:00 2001
From: jamesishimwe <james123ishimwe@gmail.com>
Date: Fri, 1 May 2026 09:27:01 +0200
Subject: [PATCH 10/28] Remove ? from the query string

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

diff --git a/Sprint-2/implement/querystring.js b/Sprint-2/implement/querystring.js
index 1dc051774..62af86fe9 100644
--- a/Sprint-2/implement/querystring.js
+++ b/Sprint-2/implement/querystring.js
@@ -3,6 +3,10 @@ function parseQueryString(queryString) {
   if (queryString.length === 0) {
     return queryParams;
   }
+  if (queryString.startsWith('?')) {
+  queryString = queryString.slice(1);
+}
+
   const keyValuePairs = queryString.split("&");
 
   for (const pair of keyValuePairs) {

From c2cc321985d30203748f64c3bbdcf46ab70e63cc Mon Sep 17 00:00:00 2001
From: jamesishimwe <james123ishimwe@gmail.com>
Date: Fri, 1 May 2026 09:32:28 +0200
Subject: [PATCH 11/28] Add code to skip empty segments

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

diff --git a/Sprint-2/implement/querystring.js b/Sprint-2/implement/querystring.js
index 62af86fe9..433604fb0 100644
--- a/Sprint-2/implement/querystring.js
+++ b/Sprint-2/implement/querystring.js
@@ -10,6 +10,7 @@ function parseQueryString(queryString) {
   const keyValuePairs = queryString.split("&");
 
   for (const pair of keyValuePairs) {
+    if (!pair) continue;
     var [key, ...value] = pair.split("=");
     value = value.join("=");
     queryParams[key] = value;
@@ -17,5 +18,5 @@ function parseQueryString(queryString) {
 
   return queryParams;
 }
-parseQueryString("equation=x=y+1");
+
 module.exports = parseQueryString;

From 8688782d82a0b5b1578d8d22514fbd2aa15b5c22 Mon Sep 17 00:00:00 2001
From: jamesishimwe <james123ishimwe@gmail.com>
Date: Fri, 1 May 2026 09:34:11 +0200
Subject: [PATCH 12/28] Add simple key value pair

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

diff --git a/Sprint-2/implement/querystring.test.js b/Sprint-2/implement/querystring.test.js
index 3e218b789..05593b6db 100644
--- a/Sprint-2/implement/querystring.test.js
+++ b/Sprint-2/implement/querystring.test.js
@@ -10,3 +10,9 @@ test("parses querystring values containing =", () => {
     "equation": "x=y+1",
   });
 });
+test("parses simple key-value pairs", () => {
+  expect(parseQueryString("name=alice&age=25")).toEqual({
+    "name": "alice",
+    "age": "25",
+  });
+});

From 4fc58195491f15256ca094ec9a7400a5ffee3edb Mon Sep 17 00:00:00 2001
From: jamesishimwe <james123ishimwe@gmail.com>
Date: Fri, 1 May 2026 09:52:58 +0200
Subject: [PATCH 13/28] Add test to check if it strips leading question marks

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

diff --git a/Sprint-2/implement/querystring.test.js b/Sprint-2/implement/querystring.test.js
index 05593b6db..4da84d18c 100644
--- a/Sprint-2/implement/querystring.test.js
+++ b/Sprint-2/implement/querystring.test.js
@@ -16,3 +16,9 @@ test("parses simple key-value pairs", () => {
     "age": "25",
   });
 });
+test("strips leading question marks", () => {
+  expect(parseQueryString("?user=bob&status=active")).toEqual({
+    "user": "bob",
+    "status": "active",
+  });
+});

From bde632c2e7dc84967a5410325e26f6f51b4c3ae8 Mon Sep 17 00:00:00 2001
From: jamesishimwe <james123ishimwe@gmail.com>
Date: Fri, 1 May 2026 10:07:55 +0200
Subject: [PATCH 14/28] Add test for null,empty and undefined

---
 Sprint-2/implement/querystring.test.js | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/Sprint-2/implement/querystring.test.js b/Sprint-2/implement/querystring.test.js
index 4da84d18c..a620df312 100644
--- a/Sprint-2/implement/querystring.test.js
+++ b/Sprint-2/implement/querystring.test.js
@@ -22,3 +22,11 @@ test("strips leading question marks", () => {
     "status": "active",
   });
 });
+test("returns empty object for empty string", () => {
+  expect(parseQueryString("")).toEqual({});
+});
+
+test("returns empty object for null or undefined", () => {
+  expect(parseQueryString(null)).toEqual({});
+  expect(parseQueryString(undefined)).toEqual({});
+});

From feb056f01e28d8716f7e4af5fe0ad418783576ad Mon Sep 17 00:00:00 2001
From: jamesishimwe <james123ishimwe@gmail.com>
Date: Fri, 1 May 2026 10:18:12 +0200
Subject: [PATCH 15/28] Add test for URL Encoded Content

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

diff --git a/Sprint-2/implement/querystring.js b/Sprint-2/implement/querystring.js
index 433604fb0..ef0415932 100644
--- a/Sprint-2/implement/querystring.js
+++ b/Sprint-2/implement/querystring.js
@@ -1,6 +1,6 @@
 function parseQueryString(queryString) {
   const queryParams = {};
-  if (queryString.length === 0) {
+ if (!queryString) {
     return queryParams;
   }
   if (queryString.startsWith('?')) {
diff --git a/Sprint-2/implement/querystring.test.js b/Sprint-2/implement/querystring.test.js
index a620df312..d5d36845d 100644
--- a/Sprint-2/implement/querystring.test.js
+++ b/Sprint-2/implement/querystring.test.js
@@ -30,3 +30,16 @@ test("returns empty object for null or undefined", () => {
   expect(parseQueryString(null)).toEqual({});
   expect(parseQueryString(undefined)).toEqual({});
 });
+test("decodes URL encoded keys and values", () => {
+  expect(parseQueryString("search=coding%20tutorials&city=New%20York")).toEqual({
+    "search": "coding tutorials",
+    "city": "New York",
+  });
+});
+
+test("decodes complex characters and emojis", () => {
+  expect(parseQueryString("item=%F0%9F%8D%95&price=%2410")).toEqual({
+    "item": "🍕",
+    "price": "$10",
+  });
+});

From 51e10b8070d0c6538668d49a195c6374af162a57 Mon Sep 17 00:00:00 2001
From: jamesishimwe <james123ishimwe@gmail.com>
Date: Fri, 1 May 2026 10:19:49 +0200
Subject: [PATCH 16/28] Add test for redudant and duplicate ampersands

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

diff --git a/Sprint-2/implement/querystring.test.js b/Sprint-2/implement/querystring.test.js
index d5d36845d..6d59062a2 100644
--- a/Sprint-2/implement/querystring.test.js
+++ b/Sprint-2/implement/querystring.test.js
@@ -43,3 +43,16 @@ test("decodes complex characters and emojis", () => {
     "price": "$10",
   });
 });
+test("ignores empty segments from double ampersands", () => {
+  expect(parseQueryString("a=1&&b=2")).toEqual({
+    "a": "1",
+    "b": "2",
+  });
+});
+
+test("ignores trailing ampersands", () => {
+  expect(parseQueryString("a=1&b=2&")).toEqual({
+    "a": "1",
+    "b": "2",
+  });
+});

From 6a3191402d58d7981c5cf625038949bb5dca97c8 Mon Sep 17 00:00:00 2001
From: jamesishimwe <james123ishimwe@gmail.com>
Date: Fri, 1 May 2026 10:20:25 +0200
Subject: [PATCH 17/28] Add test for empty and missing values

---
 Sprint-2/implement/querystring.test.js | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/Sprint-2/implement/querystring.test.js b/Sprint-2/implement/querystring.test.js
index 6d59062a2..2311841e5 100644
--- a/Sprint-2/implement/querystring.test.js
+++ b/Sprint-2/implement/querystring.test.js
@@ -56,3 +56,15 @@ test("ignores trailing ampersands", () => {
     "b": "2",
   });
 });
+test("handles keys with empty values", () => {
+  expect(parseQueryString("key=")).toEqual({
+    "key": "",
+  });
+});
+
+test("handles keys without an equals sign", () => {
+  expect(parseQueryString("flag")).toEqual({
+    "flag": "",
+  });
+});
+

From 02c49e6585dd001e38279dbc3d4a48d52aa376f6 Mon Sep 17 00:00:00 2001
From: jamesishimwe <james123ishimwe@gmail.com>
Date: Fri, 1 May 2026 10:29:39 +0200
Subject: [PATCH 18/28] Fix code to pass the decodess url encoded strings and
 complex characters tests

---
 Sprint-2/implement/querystring.js | 17 ++++++++++-------
 1 file changed, 10 insertions(+), 7 deletions(-)

diff --git a/Sprint-2/implement/querystring.js b/Sprint-2/implement/querystring.js
index ef0415932..0249b3f89 100644
--- a/Sprint-2/implement/querystring.js
+++ b/Sprint-2/implement/querystring.js
@@ -1,18 +1,21 @@
 function parseQueryString(queryString) {
   const queryParams = {};
- if (!queryString) {
-    return queryParams;
-  }
+  
+  if (!queryString) return queryParams;
+
   if (queryString.startsWith('?')) {
-  queryString = queryString.slice(1);
-}
+    queryString = queryString.slice(1);
+  }
 
   const keyValuePairs = queryString.split("&");
 
   for (const pair of keyValuePairs) {
     if (!pair) continue;
-    var [key, ...value] = pair.split("=");
-    value = value.join("=");
+    
+    const [rawKey, ...rawValue] = pair.split("=");
+    const key = decodeURIComponent(rawKey);
+    const value = decodeURIComponent(rawValue.join("="));
+    
     queryParams[key] = value;
   }
 

From f370fe331d61ae7da79842c48dc3b5a5c736e130 Mon Sep 17 00:00:00 2001
From: jamesishimwe <james123ishimwe@gmail.com>
Date: Fri, 1 May 2026 10:44:15 +0200
Subject: [PATCH 19/28] Add test for empty array

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

diff --git a/Sprint-2/implement/tally.test.js b/Sprint-2/implement/tally.test.js
index 2ceffa8dd..d8ca58263 100644
--- a/Sprint-2/implement/tally.test.js
+++ b/Sprint-2/implement/tally.test.js
@@ -24,6 +24,9 @@ const tally = require("./tally.js");
 // When passed to tally
 // Then it should return an empty object
 test.todo("tally on an empty array returns an empty object");
+test("Empty array of items",()=>{
+    expect([]).toEqual({});
+});
 
 // Given an array with duplicate items
 // When passed to tally

From fa3b44255118032bc86408fa932bbd334516f9f9 Mon Sep 17 00:00:00 2001
From: jamesishimwe <james123ishimwe@gmail.com>
Date: Fri, 1 May 2026 10:53:50 +0200
Subject: [PATCH 20/28] Add code for the empty array

---
 Sprint-2/implement/tally.js      | 8 +++++++-
 Sprint-2/implement/tally.test.js | 6 +++++-
 2 files changed, 12 insertions(+), 2 deletions(-)

diff --git a/Sprint-2/implement/tally.js b/Sprint-2/implement/tally.js
index f47321812..e87c86905 100644
--- a/Sprint-2/implement/tally.js
+++ b/Sprint-2/implement/tally.js
@@ -1,3 +1,9 @@
-function tally() {}
+function tally(array) {
+    const tally = {};
+    if(array.length === 0)
+    return tally;
+    
+
+}
 
 module.exports = tally;
diff --git a/Sprint-2/implement/tally.test.js b/Sprint-2/implement/tally.test.js
index d8ca58263..06bc9b67d 100644
--- a/Sprint-2/implement/tally.test.js
+++ b/Sprint-2/implement/tally.test.js
@@ -25,7 +25,7 @@ const tally = require("./tally.js");
 // Then it should return an empty object
 test.todo("tally on an empty array returns an empty object");
 test("Empty array of items",()=>{
-    expect([]).toEqual({});
+    expect(tally([])).toEqual({});
 });
 
 // Given an array with duplicate items
@@ -35,3 +35,7 @@ test("Empty array of items",()=>{
 // Given an invalid input like a string
 // When passed to tally
 // Then it should throw an error
+
+test("Invalid input",()=>{
+    expect(tally("some string")).toThrow();
+});
\ No newline at end of file

From 4176d2402c7ab41df232b8d2db6fcdaa2b750b87 Mon Sep 17 00:00:00 2001
From: jamesishimwe <james123ishimwe@gmail.com>
Date: Fri, 1 May 2026 11:13:10 +0200
Subject: [PATCH 21/28] Add code for throwing error if not array

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

diff --git a/Sprint-2/implement/tally.js b/Sprint-2/implement/tally.js
index e87c86905..5fb0736ae 100644
--- a/Sprint-2/implement/tally.js
+++ b/Sprint-2/implement/tally.js
@@ -1,5 +1,7 @@
 function tally(array) {
     const tally = {};
+    if(!Array.isArray(array))
+        throw new TypeError("Expected an array");
     if(array.length === 0)
     return tally;
     

From e0f7967eb65332404ec40e19af3046925eb6353d Mon Sep 17 00:00:00 2001
From: jamesishimwe <james123ishimwe@gmail.com>
Date: Fri, 1 May 2026 11:45:30 +0200
Subject: [PATCH 22/28] Add test for not array

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

diff --git a/Sprint-2/implement/tally.test.js b/Sprint-2/implement/tally.test.js
index 06bc9b67d..f37f78f2e 100644
--- a/Sprint-2/implement/tally.test.js
+++ b/Sprint-2/implement/tally.test.js
@@ -37,5 +37,5 @@ test("Empty array of items",()=>{
 // Then it should throw an error
 
 test("Invalid input",()=>{
-    expect(tally("some string")).toThrow();
+    expect(() => tally("not an array")).toThrow(TypeError);
 });
\ No newline at end of file

From 85dab098c8b20755575f124b5e4ff515b6271b33 Mon Sep 17 00:00:00 2001
From: jamesishimwe <james123ishimwe@gmail.com>
Date: Fri, 1 May 2026 11:49:46 +0200
Subject: [PATCH 23/28] Add code for counting duplicates

---
 Sprint-2/implement/tally.js      | 5 ++++-
 Sprint-2/implement/tally.test.js | 2 +-
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/Sprint-2/implement/tally.js b/Sprint-2/implement/tally.js
index 5fb0736ae..a444edc2f 100644
--- a/Sprint-2/implement/tally.js
+++ b/Sprint-2/implement/tally.js
@@ -4,7 +4,10 @@ function tally(array) {
         throw new TypeError("Expected an array");
     if(array.length === 0)
     return tally;
-    
+for (const item of array) {
+        tally[item] = (tally[item] || 0) + 1;
+    }
+    return tally;
 
 }
 
diff --git a/Sprint-2/implement/tally.test.js b/Sprint-2/implement/tally.test.js
index f37f78f2e..c01e2e3f6 100644
--- a/Sprint-2/implement/tally.test.js
+++ b/Sprint-2/implement/tally.test.js
@@ -38,4 +38,4 @@ test("Empty array of items",()=>{
 
 test("Invalid input",()=>{
     expect(() => tally("not an array")).toThrow(TypeError);
-});
\ No newline at end of file
+}); 
\ No newline at end of file

From b046080dec2196a530adc6a02ebc825ee64f8a63 Mon Sep 17 00:00:00 2001
From: jamesishimwe <james123ishimwe@gmail.com>
Date: Fri, 1 May 2026 11:53:01 +0200
Subject: [PATCH 24/28] Add test for duplicate array

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

diff --git a/Sprint-2/implement/tally.test.js b/Sprint-2/implement/tally.test.js
index c01e2e3f6..33bfcda39 100644
--- a/Sprint-2/implement/tally.test.js
+++ b/Sprint-2/implement/tally.test.js
@@ -38,4 +38,13 @@ test("Empty array of items",()=>{
 
 test("Invalid input",()=>{
     expect(() => tally("not an array")).toThrow(TypeError);
-}); 
\ No newline at end of file
+}); 
+test("Test duplicate array",()=>{
+const duplicatesArray = ['apple', 'banana', 'apple', 'orange', 'banana', 'apple'];
+const result = tally(duplicatesArray);
+    expect(result).toEqual({
+      apple: 3,
+      banana: 2,
+      orange: 1,
+    });
+});
\ No newline at end of file

From 29cfb099df6ecf39d3ff41299e83ce94cf870c59 Mon Sep 17 00:00:00 2001
From: jamesishimwe <james123ishimwe@gmail.com>
Date: Fri, 1 May 2026 12:02:46 +0200
Subject: [PATCH 25/28] Fix the code and answer the questions

---
 Sprint-2/interpret/invert.js | 21 ++++++++++++++++++++-
 1 file changed, 20 insertions(+), 1 deletion(-)

diff --git a/Sprint-2/interpret/invert.js b/Sprint-2/interpret/invert.js
index bb353fb1f..91f7707d9 100644
--- a/Sprint-2/interpret/invert.js
+++ b/Sprint-2/interpret/invert.js
@@ -5,7 +5,7 @@
 // Then it should swap the keys and values in the object
 
 // E.g. invert({x : 10, y : 20}), target output: {"10": "x", "20": "y"}
-
+/*
 function invert(obj) {
   const invertedObj = {};
 
@@ -17,13 +17,32 @@ function invert(obj) {
 }
 
 // a) What is the current return value when invert is called with { a : 1 }
+//{ key: 1 }
 
 // b) What is the current return value when invert is called with { a: 1, b: 2 }
+//{ 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?
+//It returns An array of the object's own property [key, value] pairs.
+// It allows the for...of loop to easily access both the key and the value at the same time during each iteration.
 
 // d) Explain why the current return value is different from the target output
+//Using invertedObj.key creates a literal property named "key" on the object. 
+// To use the value inside the key variable, you must use bracket notation: invertedObj[key].
+//The function is setting the original value to the key. 
+// To actually "invert" the object, it needs to swap them: invertedObj[value] = key;.
 
 // e) Fix the implementation of invert (and write tests to prove it's fixed!)
+*/
+function invert(obj) {
+  const invertedObj = {};
+
+  for (const [key, value] of Object.entries(obj)) {
+    invertedObj[value] = key;
+  }
+
+  return invertedObj;
+}
\ No newline at end of file

From 20d5acca65b01fbabc7c4507ce8a71bebd3dfe59 Mon Sep 17 00:00:00 2001
From: jamesishimwe <james123ishimwe@gmail.com>
Date: Fri, 1 May 2026 12:04:45 +0200
Subject: [PATCH 26/28] Create test file for invert

---
 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..b8b93fb2d
--- /dev/null
+++ b/Sprint-2/interpret/invert.test.js
@@ -0,0 +1 @@
+const invert = require("./invert.js");
\ No newline at end of file

From 6cc9c372550623442b39fb45d5e8c0243abecee6 Mon Sep 17 00:00:00 2001
From: jamesishimwe <james123ishimwe@gmail.com>
Date: Fri, 1 May 2026 12:10:38 +0200
Subject: [PATCH 27/28] Create test for the invert function

---
 Sprint-2/interpret/invert.js      |  3 ++-
 Sprint-2/interpret/invert.test.js | 25 ++++++++++++++++++++++++-
 2 files changed, 26 insertions(+), 2 deletions(-)

diff --git a/Sprint-2/interpret/invert.js b/Sprint-2/interpret/invert.js
index 91f7707d9..7a7767454 100644
--- a/Sprint-2/interpret/invert.js
+++ b/Sprint-2/interpret/invert.js
@@ -45,4 +45,5 @@ function invert(obj) {
   }
 
   return invertedObj;
-}
\ No newline at end of file
+}
+module.exports = invert;
\ No newline at end of file
diff --git a/Sprint-2/interpret/invert.test.js b/Sprint-2/interpret/invert.test.js
index b8b93fb2d..ff3f2afda 100644
--- a/Sprint-2/interpret/invert.test.js
+++ b/Sprint-2/interpret/invert.test.js
@@ -1 +1,24 @@
-const invert = require("./invert.js");
\ No newline at end of file
+const invert = require("./invert.js");
+test('inverts a single key-value pair', () => {
+    const input = { a: 1 };
+    expect(invert(input)).toEqual({ 1: 'a' });
+  });
+test('inverts multiple key-value pairs', () => {
+    const input = { a: 1, b: 2, c: 3 };
+    const expected = { 1: 'a', 2: 'b', 3: 'c' };
+    
+    expect(invert(input)).toEqual(expected);
+  });
+   test('returns empty object for empty input', () => {
+    expect(invert({})).toEqual({});
+  });
+  test('overwrites keys when duplicate values exist', () => {
+    const input = { a: 1, b: 1 };
+    expect(invert(input)).toEqual({ 1: 'b' });
+  });
+  test('turns boolean and null values into string keys', () => {
+    const input = { a: true, b: null };
+    const expected = { 'true': 'a', 'null': 'b' };
+    
+    expect(invert(input)).toEqual(expected);
+  });
\ No newline at end of file

From 24b56be28b3d93213f50dee0466f308b5a0227f1 Mon Sep 17 00:00:00 2001
From: jamesishimwe <james123ishimwe@gmail.com>
Date: Fri, 1 May 2026 12:28:25 +0200
Subject: [PATCH 28/28] Format the code

---
 Sprint-2/debug/address.js              |  2 +-
 Sprint-2/implement/contains.js         |  7 ++--
 Sprint-2/implement/contains.test.js    |  2 +-
 Sprint-2/implement/lookup.js           |  4 +--
 Sprint-2/implement/lookup.test.js      | 27 ++++++++++-----
 Sprint-2/implement/querystring.js      |  8 ++---
 Sprint-2/implement/querystring.test.js | 39 +++++++++++-----------
 Sprint-2/implement/tally.js            | 17 ++++------
 Sprint-2/implement/tally.test.js       | 35 ++++++++++++--------
 Sprint-2/interpret/invert.js           |  2 +-
 Sprint-2/interpret/invert.test.js      | 46 +++++++++++++-------------
 11 files changed, 102 insertions(+), 87 deletions(-)

diff --git a/Sprint-2/debug/address.js b/Sprint-2/debug/address.js
index f28985431..36d2f865d 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.houseNumber}`);
\ No newline at end of file
+console.log(`My house number is ${address.houseNumber}`);
diff --git a/Sprint-2/implement/contains.js b/Sprint-2/implement/contains.js
index bd1be68b4..6b3ef26b9 100644
--- a/Sprint-2/implement/contains.js
+++ b/Sprint-2/implement/contains.js
@@ -1,6 +1,7 @@
-function contains(Obj,key) {
-    if(Obj === null || typeof Obj !== "object" || Array.isArray(Obj)) return false;
-     return Object.prototype.hasOwnProperty.call(Obj, key);
+function contains(Obj, key) {
+  if (Obj === null || typeof Obj !== "object" || Array.isArray(Obj))
+    return false;
+  return Object.prototype.hasOwnProperty.call(Obj, key);
 }
 
 module.exports = contains;
diff --git a/Sprint-2/implement/contains.test.js b/Sprint-2/implement/contains.test.js
index a631e6414..0c4b1ced3 100644
--- a/Sprint-2/implement/contains.test.js
+++ b/Sprint-2/implement/contains.test.js
@@ -48,4 +48,4 @@ test("returns false when property does not exist", () => {
 
 test("returns false for invalid input like array", () => {
   expect(contains([1, 2, 3], "0")).toEqual(false);
-});
\ No newline at end of file
+});
diff --git a/Sprint-2/implement/lookup.js b/Sprint-2/implement/lookup.js
index 1839a7455..3281fdf20 100644
--- a/Sprint-2/implement/lookup.js
+++ b/Sprint-2/implement/lookup.js
@@ -1,8 +1,8 @@
 function createLookup(countryCurrencyPairs) {
-   if (!Array.isArray(countryCurrencyPairs)) {
+  if (!Array.isArray(countryCurrencyPairs)) {
     return {};
   }
-return Object.fromEntries(countryCurrencyPairs);
+  return Object.fromEntries(countryCurrencyPairs);
 }
 
 module.exports = createLookup;
diff --git a/Sprint-2/implement/lookup.test.js b/Sprint-2/implement/lookup.test.js
index a27e6ba44..d92c73101 100644
--- a/Sprint-2/implement/lookup.test.js
+++ b/Sprint-2/implement/lookup.test.js
@@ -34,30 +34,39 @@ It should return:
  }
 */
 
-
 test("returns empty object for empty array", () => {
   expect(createLookup([])).toEqual({});
 });
 
 test("creates lookup from country-currency pairs", () => {
-  expect(createLookup([['US', 'USD'], ['CA', 'CAD']])).toEqual({
-    US: 'USD',
-    CA: 'CAD',
+  expect(
+    createLookup([
+      ["US", "USD"],
+      ["CA", "CAD"],
+    ])
+  ).toEqual({
+    US: "USD",
+    CA: "CAD",
   });
 });
 
 test("handles single pair", () => {
-  expect(createLookup([['JP', 'JPY']])).toEqual({
-    JP: 'JPY',
+  expect(createLookup([["JP", "JPY"]])).toEqual({
+    JP: "JPY",
   });
 });
 
 test("overwrites duplicate country codes (last one wins)", () => {
-  expect(createLookup([['US', 'USD'], ['US', 'USN']])).toEqual({
-    US: 'USN',
+  expect(
+    createLookup([
+      ["US", "USD"],
+      ["US", "USN"],
+    ])
+  ).toEqual({
+    US: "USN",
   });
 });
 
 test("handles invalid input (non-array)", () => {
   expect(createLookup(null)).toEqual({});
-});
\ No newline at end of file
+});
diff --git a/Sprint-2/implement/querystring.js b/Sprint-2/implement/querystring.js
index 0249b3f89..0872f83fa 100644
--- a/Sprint-2/implement/querystring.js
+++ b/Sprint-2/implement/querystring.js
@@ -1,9 +1,9 @@
 function parseQueryString(queryString) {
   const queryParams = {};
-  
+
   if (!queryString) return queryParams;
 
-  if (queryString.startsWith('?')) {
+  if (queryString.startsWith("?")) {
     queryString = queryString.slice(1);
   }
 
@@ -11,11 +11,11 @@ function parseQueryString(queryString) {
 
   for (const pair of keyValuePairs) {
     if (!pair) continue;
-    
+
     const [rawKey, ...rawValue] = pair.split("=");
     const key = decodeURIComponent(rawKey);
     const value = decodeURIComponent(rawValue.join("="));
-    
+
     queryParams[key] = value;
   }
 
diff --git a/Sprint-2/implement/querystring.test.js b/Sprint-2/implement/querystring.test.js
index 2311841e5..e6b0e31df 100644
--- a/Sprint-2/implement/querystring.test.js
+++ b/Sprint-2/implement/querystring.test.js
@@ -3,23 +3,23 @@
 // Below is one test case for an edge case the implementation doesn't handle well.
 // Fix the implementation for this test, 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("parses querystring values containing =", () => {
   expect(parseQueryString("equation=x=y+1")).toEqual({
-    "equation": "x=y+1",
+    equation: "x=y+1",
   });
 });
 test("parses simple key-value pairs", () => {
   expect(parseQueryString("name=alice&age=25")).toEqual({
-    "name": "alice",
-    "age": "25",
+    name: "alice",
+    age: "25",
   });
 });
 test("strips leading question marks", () => {
   expect(parseQueryString("?user=bob&status=active")).toEqual({
-    "user": "bob",
-    "status": "active",
+    user: "bob",
+    status: "active",
   });
 });
 test("returns empty object for empty string", () => {
@@ -31,40 +31,41 @@ test("returns empty object for null or undefined", () => {
   expect(parseQueryString(undefined)).toEqual({});
 });
 test("decodes URL encoded keys and values", () => {
-  expect(parseQueryString("search=coding%20tutorials&city=New%20York")).toEqual({
-    "search": "coding tutorials",
-    "city": "New York",
-  });
+  expect(parseQueryString("search=coding%20tutorials&city=New%20York")).toEqual(
+    {
+      search: "coding tutorials",
+      city: "New York",
+    }
+  );
 });
 
 test("decodes complex characters and emojis", () => {
   expect(parseQueryString("item=%F0%9F%8D%95&price=%2410")).toEqual({
-    "item": "🍕",
-    "price": "$10",
+    item: "🍕",
+    price: "$10",
   });
 });
 test("ignores empty segments from double ampersands", () => {
   expect(parseQueryString("a=1&&b=2")).toEqual({
-    "a": "1",
-    "b": "2",
+    a: "1",
+    b: "2",
   });
 });
 
 test("ignores trailing ampersands", () => {
   expect(parseQueryString("a=1&b=2&")).toEqual({
-    "a": "1",
-    "b": "2",
+    a: "1",
+    b: "2",
   });
 });
 test("handles keys with empty values", () => {
   expect(parseQueryString("key=")).toEqual({
-    "key": "",
+    key: "",
   });
 });
 
 test("handles keys without an equals sign", () => {
   expect(parseQueryString("flag")).toEqual({
-    "flag": "",
+    flag: "",
   });
 });
-
diff --git a/Sprint-2/implement/tally.js b/Sprint-2/implement/tally.js
index a444edc2f..94a6da1cb 100644
--- a/Sprint-2/implement/tally.js
+++ b/Sprint-2/implement/tally.js
@@ -1,14 +1,11 @@
 function tally(array) {
-    const tally = {};
-    if(!Array.isArray(array))
-        throw new TypeError("Expected an array");
-    if(array.length === 0)
-    return tally;
-for (const item of array) {
-        tally[item] = (tally[item] || 0) + 1;
-    }
-    return tally;
-
+  const tally = {};
+  if (!Array.isArray(array)) throw new TypeError("Expected an array");
+  if (array.length === 0) return tally;
+  for (const item of array) {
+    tally[item] = (tally[item] || 0) + 1;
+  }
+  return tally;
 }
 
 module.exports = tally;
diff --git a/Sprint-2/implement/tally.test.js b/Sprint-2/implement/tally.test.js
index 33bfcda39..6b0888faf 100644
--- a/Sprint-2/implement/tally.test.js
+++ b/Sprint-2/implement/tally.test.js
@@ -24,8 +24,8 @@ const tally = require("./tally.js");
 // When passed to tally
 // Then it should return an empty object
 test.todo("tally on an empty array returns an empty object");
-test("Empty array of items",()=>{
-    expect(tally([])).toEqual({});
+test("Empty array of items", () => {
+  expect(tally([])).toEqual({});
 });
 
 // Given an array with duplicate items
@@ -36,15 +36,22 @@ test("Empty array of items",()=>{
 // When passed to tally
 // Then it should throw an error
 
-test("Invalid input",()=>{
-    expect(() => tally("not an array")).toThrow(TypeError);
-}); 
-test("Test duplicate array",()=>{
-const duplicatesArray = ['apple', 'banana', 'apple', 'orange', 'banana', 'apple'];
-const result = tally(duplicatesArray);
-    expect(result).toEqual({
-      apple: 3,
-      banana: 2,
-      orange: 1,
-    });
-});
\ No newline at end of file
+test("Invalid input", () => {
+  expect(() => tally("not an array")).toThrow(TypeError);
+});
+test("Test duplicate array", () => {
+  const duplicatesArray = [
+    "apple",
+    "banana",
+    "apple",
+    "orange",
+    "banana",
+    "apple",
+  ];
+  const result = tally(duplicatesArray);
+  expect(result).toEqual({
+    apple: 3,
+    banana: 2,
+    orange: 1,
+  });
+});
diff --git a/Sprint-2/interpret/invert.js b/Sprint-2/interpret/invert.js
index 7a7767454..f35a148fa 100644
--- a/Sprint-2/interpret/invert.js
+++ b/Sprint-2/interpret/invert.js
@@ -46,4 +46,4 @@ function invert(obj) {
 
   return invertedObj;
 }
-module.exports = invert;
\ No newline at end of file
+module.exports = invert;
diff --git a/Sprint-2/interpret/invert.test.js b/Sprint-2/interpret/invert.test.js
index ff3f2afda..5f879e88e 100644
--- a/Sprint-2/interpret/invert.test.js
+++ b/Sprint-2/interpret/invert.test.js
@@ -1,24 +1,24 @@
 const invert = require("./invert.js");
-test('inverts a single key-value pair', () => {
-    const input = { a: 1 };
-    expect(invert(input)).toEqual({ 1: 'a' });
-  });
-test('inverts multiple key-value pairs', () => {
-    const input = { a: 1, b: 2, c: 3 };
-    const expected = { 1: 'a', 2: 'b', 3: 'c' };
-    
-    expect(invert(input)).toEqual(expected);
-  });
-   test('returns empty object for empty input', () => {
-    expect(invert({})).toEqual({});
-  });
-  test('overwrites keys when duplicate values exist', () => {
-    const input = { a: 1, b: 1 };
-    expect(invert(input)).toEqual({ 1: 'b' });
-  });
-  test('turns boolean and null values into string keys', () => {
-    const input = { a: true, b: null };
-    const expected = { 'true': 'a', 'null': 'b' };
-    
-    expect(invert(input)).toEqual(expected);
-  });
\ No newline at end of file
+test("inverts a single key-value pair", () => {
+  const input = { a: 1 };
+  expect(invert(input)).toEqual({ 1: "a" });
+});
+test("inverts multiple key-value pairs", () => {
+  const input = { a: 1, b: 2, c: 3 };
+  const expected = { 1: "a", 2: "b", 3: "c" };
+
+  expect(invert(input)).toEqual(expected);
+});
+test("returns empty object for empty input", () => {
+  expect(invert({})).toEqual({});
+});
+test("overwrites keys when duplicate values exist", () => {
+  const input = { a: 1, b: 1 };
+  expect(invert(input)).toEqual({ 1: "b" });
+});
+test("turns boolean and null values into string keys", () => {
+  const input = { a: true, b: null };
+  const expected = { true: "a", null: "b" };
+
+  expect(invert(input)).toEqual(expected);
+});