Add almost-fully-function .csv function

Author: thecodepixi

.d.ts

@@ -1,4 +1,10 @@
 export default class Split {
   it(str: string): string[];
   onDelimiter(str: string, del?: string): string[];
+  csv(data: string, options?: Options): string[];
 }
+
+type Options = {
+  headings?: boolean;
+  splitOnColumns?: boolean;
+};

index.js

@@ -27,6 +27,32 @@ class Split {
       return str.split(/\s/g);
     }
   };
+
+  /**
+   *
+   * @param {string} data the csv data to be manipulated
+   * @param options an object containing boolean values for "headings" and "splitOnColumns"
+   * @return {string[]}
+   */
+  csv = (data, { headings = true, splitOnColumns = false } = {}) => {
+    let rows = data.split(/\r\n|\n|\r/g).map((row) => row.split(/,\s+/g));
+    let returnData = [];
+
+    if (splitOnColumns) {
+      rows.forEach((row, index) => {
+        //  TO DO: FIGURE OUT HOW TO ROTATE THIS SHIT
+      });
+    } else {
+      returnData = rows;
+    }
+
+    if (!headings) {
+      returnData.shift();
+      returnData.forEach((row) => row.shift());
+    }
+
+    return returnData;
+  };
 }
 
 module.exports = new Split();

test.csv

@@ -0,0 +1,13 @@
+"Month", "1958", "1959", "1960"
+"JAN",  340,  360,  417
+"FEB",  318,  342,  391
+"MAR",  362,  406,  419
+"APR",  348,  396,  461
+"MAY",  363,  420,  472
+"JUN",  435,  472,  535
+"JUL",  491,  548,  622
+"AUG",  505,  559,  606
+"SEP",  404,  463,  508
+"OCT",  359,  407,  461
+"NOV",  310,  362,  390
+"DEC",  337,  405,  432

test/index.test.js

@@ -1,4 +1,5 @@
 const Split = require('../index');
+const fs = require('fs');
 
 const expected = ['hello', 'from', 'split-it'];
 
@@ -66,4 +67,51 @@ describe('Split', () => {
       expect(Split.onDelimiter(str3, '*')).toEqual(expected);
     });
   });
+
+  describe('.csv', () => {
+    const DATA = fs.readFileSync('airtravel.csv', { encoding: 'utf-8' });
+
+    test('splits csv data into a multi-array array', () => {
+      let parsed = Split.csv(DATA);
+
+      expect(parsed.length).toEqual(13);
+
+      parsed.forEach((arr) => {
+        expect(arr.length).toEqual(4);
+      });
+    });
+
+    test('removes headings when option is passed as false', () => {
+      let parsed = Split.csv(DATA, { headings: false });
+
+      expect(parsed.length).toEqual(12);
+
+      parsed.forEach((arr) => {
+        expect(arr.length).toEqual(3);
+      });
+    });
+
+    test('rotates data to make arrays of columns when option is passed', () => {
+      let parsed = Split.csv(DATA, { splitOnColumns: true });
+      let expectedHeadings = [
+        'Month',
+        'JAN',
+        'FEB',
+        'MAR',
+        'APR',
+        'MAY',
+        'JUN',
+        'JUL',
+        'AUG',
+        'SEP',
+        'OCT',
+        'NOV',
+        'DEC',
+      ];
+
+      expect(parsed.length).toEqual(4);
+      expect(parsed[0].length).toEqual(13);
+      expect(parsed[0]).toEqual(expectedHeadings);
+    });
+  });
 });