Implement a solution to build a piramid with n levels, write tests

Author: somekindofwallflower

10_pyramid/index.js

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+// --- Directions
+// Write a function that accepts a positive number N.
+// The function should console log a pyramid shape
+// with N levels using the # character.  Make sure the
+// pyramid has spaces on both the left *and* right hand sides
+// --- Examples
+//   pyramid(1)
+//       '#'
+//   pyramid(2)
+//       ' # '
+//       '###'
+//   pyramid(3)
+//       '  #  '
+//       ' ### '
+//       '#####'
+
+// Solution 1
+// function pyramid(n) {
+//     const midPoint = Math.floor((2 * n - 1)/2)
+//     for(let row = 0; row < n; row++) {
+//         let level = '';
+//         for(let column = 0; column < 2*n - 1; column++) {
+//             if(midPoint - row <= column && midPoint + row >=column) {
+//                 level += '#'
+//             } else {
+//                 level += ' '
+//             }
+//         }
+//         console.log(level);
+//     }
+// }
+
+// Solution 2
+function pyramid(n, row = 0, str = "") {
+    if (n === row) {
+        return;
+    }
+    const midPoint = Math.floor((2 * n - 1) / 2)
+    if (str.length === 2 * n - 1) {
+        console.log(str);
+        return pyramid(n, row + 1)
+    } else {
+        if (midPoint - row <= str.length && midPoint + row >= str.length) {
+            str += '#'
+        } else {
+            str += ' '
+        }
+        return pyramid(n, row, str)
+    }
+}
+
+module.exports = pyramid;

10_pyramid/test.js

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+const pyramid = require('./index');
+
+beforeEach(() => {
+    jest.spyOn(console, 'log');
+});
+
+afterEach(() => {
+    console.log.mockRestore();
+});
+
+test('pyramid is a function', () => {
+    expect(typeof pyramid).toEqual('function');
+});
+
+test('prints a pryamid for n = 2', () => {
+    pyramid(2);
+    expect(console.log.mock.calls[0][0]).toEqual(' # ');
+    expect(console.log.mock.calls[1][0]).toEqual('###');
+    expect(console.log.mock.calls.length).toEqual(2);
+});
+
+test('prints a pryamid for n = 3', () => {
+    pyramid(3);
+    expect(console.log.mock.calls[0][0]).toEqual('  #  ');
+    expect(console.log.mock.calls[1][0]).toEqual(' ### ');
+    expect(console.log.mock.calls[2][0]).toEqual('#####');
+    expect(console.log.mock.calls.length).toEqual(3);
+});
+
+test('prints a pryamid for n = 4', () => {
+    pyramid(4);
+    expect(console.log.mock.calls[0][0]).toEqual('   #   ');
+    expect(console.log.mock.calls[1][0]).toEqual('  ###  ');
+    expect(console.log.mock.calls[2][0]).toEqual(' ##### ');
+    expect(console.log.mock.calls[3][0]).toEqual('#######');
+    expect(console.log.mock.calls.length).toEqual(4);
+});