fix(csv2json): throw on invalid input. add tests

src/lib/cs2json.spec.ts

@@ -0,0 +1,47 @@
+import csv2json from './csv2json';
+
+/*
+const toBeType = require('jest-tobetype').toBeType;
+
+expect.extend({
+  toBeType,
+});
+*/
+
+/*
+const toBeType = require("jest-tobetype");
+expect.extend(toBeType);
+*/
+
+describe('csv2json', () => {
+
+  it('handles historical input', () => {
+    const csv =
+      "Date,Open,High,Low,Close,Adj Close,Volume\n" +
+      "2020-10-29,112.370003,116.930000,112.199997,115.320000,115.121384,146129200\n" +
+      "2020-10-30,111.059998,111.989998,107.720001,108.860001,108.672516,190272600";
+
+    const obj = csv2json(csv);
+    expect(obj.length).toBe(2);
+
+    // camelcase
+    const headers = Object.keys(obj[0]);
+    expect(headers[0]).toBe('date');
+    expect(headers[5]).toBe('adjClose');
+
+    expect(obj[0].date).toBeInstanceOf(Date);
+    expect(obj[0].open).toBeType('number');
+  });
+
+  it("returns anything else - not actually used in historical", () => {
+    const csv = "string\nstring";
+    const obj = csv2json(csv);
+    expect(obj[0].string).toBeType('string');
+  });
+
+  it('throws on weird file (no newlines)', () => {
+    const csv ="one line file";
+    expect(() => csv2json(csv)).toThrow(/No newlines/);
+  });
+
+});

src/lib/csv2json.ts

@@ -17,7 +17,7 @@ function convert(input: any) {
 
 export default function csv2json(csv: string): Array<any> {
   const lines = csv.split('\n');
-  if (lines.length === 0)
+  if (lines.length === 1)
     throw new Error("No newlines in: " + csv);
 
   const headers = (lines.shift() as string).split(DELIMITER).map(camelize);