Fixes for Sprint 1 (#47)

* Fix up typos in exercises
* Update a bunch of week-1s to Sprint-1s
* Use toEqual not toBe
* Add a bit more scaffolding for exports and requires, as we currently
  don't reliably teach this.
* Add a few more edge cases to test for
* Move root package.json to Sprint-3 directory, because that's the set
  of tests it hard-codes as modules, and rework instructions to not
  assume you're installing stuff in the root of the repo.
* Change refactor exercises from implementing `find` to implementing
  `includes` - because `find` returns the index, I would consider it
  better implemented with a for-with-index loop than a for..of loop.
  `includes` does not share this property.

Author: illicitonion

Sprint-1/fix/median.js

@@ -1,6 +1,6 @@
 // Fix this implementation
 // Start by running the tests for this function
-// If you're in the week-1 directory, you can run npm test -- fix to run the tests in the fix directory
+// If you're in the Sprint-1 directory, you can run `npm test -- fix` to run the tests in the fix directory
 
 function calculateMedian(list) {
   const middleIndex = Math.floor(list.length / 2);

Sprint-1/fix/median.test.js

@@ -8,13 +8,13 @@ const calculateMedian = require("./median.js");
 
 describe("calculateMedian", () => {
   test("returns the median for odd length array", () => {
-    expect(calculateMedian([1, 2, 3])).toBe(2);
-    expect(calculateMedian([1, 2, 3, 4, 5])).toBe(3);
+    expect(calculateMedian([1, 2, 3])).toEqual(2);
+    expect(calculateMedian([1, 2, 3, 4, 5])).toEqual(3);
   });
 
   test("returns the average of middle values for even length array", () => {
-    expect(calculateMedian([1, 2, 3, 4])).toBe(2.5);
-    expect(calculateMedian([1, 2, 3, 4, 5, 6])).toBe(3.5);
+    expect(calculateMedian([1, 2, 3, 4])).toEqual(2.5);
+    expect(calculateMedian([1, 2, 3, 4, 5, 6])).toEqual(3.5);
   });
 
   test("doesn't modify the input", () => {

Sprint-1/implement/dedupe.test.js

@@ -8,6 +8,7 @@ In this kata, you will need to deduplicate the elements of an array
 
 E.g. dedupe(['a','a','a','b','b','c']) target output: ['a','b','c']
 E.g. dedupe([5, 1, 1, 2, 3, 2, 5, 8]) target output: [5, 1, 2, 3, 8]
+E.g. dedupe([1, 2, 1]) target output: [1, 2]
 */
 
 // Acceptance Criteria:
@@ -23,4 +24,4 @@ test.todo("given an empty array, it returns an empty array");
 
 // Given an array with strings or numbers
 // When passed to the dedupe function
-// Then it should remove the duplicate values
+// Then it should remove the duplicate values, preserving the first occurence of each element

Sprint-1/implement/max.js

@@ -0,0 +1,4 @@
+function findMax(elements) {
+}
+
+module.exports = findMax;

Sprint-1/implement/max.test.js

@@ -1,14 +1,21 @@
 /* Find the maximum element of an array of numbers
 
-In this kata, you will need to implement a function that sums the numerical elements of an array
+In this kata, you will need to implement a function that find the largest numerical element of an array.
 
 E.g. max([30, 50, 10, 40]), target output: 50
 E.g. max(['hey', 10, 'hi', 60, 10]), target output: 60 (sum ignores any non-numerical elements)
+
+You should implement this function in max.js, and add tests for it in this file.
+
+We have set things up already so that this file can see your function from the other file.
 */
 
+const findMax = require("./max.js");
+
 // Given an empty array
 // When passed to the max function
 // Then it should return -Infinity
+// Delete this test.todo and replace it with a test.
 test.todo("given an empty array, returns -Infinity");
 
 // Given an array with one number
@@ -19,10 +26,18 @@ test.todo("given an empty array, returns -Infinity");
 // When passed to the max function
 // Then it should return the largest number overall
 
+// Given an array with just negative numbers
+// When passed to the max function
+// Then it should return the closest one to zero
+
 // Given an array with decimal numbers
 // When passed to the max function
 // Then it should return the largest decimal number
 
 // Given an array with non-number values
 // When passed to the max function
 // Then it should return the max and ignore non-numeric values
+
+// Given an array with only non-number values
+// When passed to the max function
+// Then it should return the least surprising value given how it behaves for all other inputs

Sprint-1/implement/sum.js

@@ -0,0 +1,4 @@
+function sum(elements) {
+}
+
+module.exports = sum;

Sprint-1/implement/sum.test.js

@@ -6,11 +6,14 @@ E.g. sum([10, 20, 30]), target output: 60
 E.g. sum(['hey', 10, 'hi', 60, 10]), target output: 80 (ignore any non-numerical elements)
 */
 
+const sum = require("./sum.js");
+
 // Acceptance Criteria:
 
 // Given an empty array
 // When passed to the sum function
 // Then it should return 0
+test.todo("given an empty array, returns 0")
 
 // Given an array with just one number
 // When passed to the sum function
@@ -27,3 +30,7 @@ E.g. sum(['hey', 10, 'hi', 60, 10]), target output: 80 (ignore any non-numerical
 // Given an array containing non-number values
 // When passed to the sum function
 // Then it should ignore the non-numerical values and return the sum of the numerical elements
+
+// Given an array with only non-number values
+// When passed to the sum function
+// Then it should return the least surprising value given how it behaves for all other inputs