Add tryConversion option to priceHistorical()

- Update docs
- Harden tests

README.md

@@ -27,7 +27,7 @@ Usage
 
 ### `price()`
 
-`price(fsym, tsyms, [tryConversion])`
+`price(fsym, tsyms[, tryConversion])`
 
 - `fsym` (String) From Symbol
 - `tsym` (Array of Strings | String) To Symbol(s)
@@ -55,11 +55,12 @@ cc.price('BTC', 'USD')
 
 ### priceHistorical
 
-`priceHistorical(fsym, tsyms, time)`
+`priceHistorical(fsym, tsyms, time[, tryConversion])`
 
 - `fsym` (String) From Symbol
 - `tsym` (Array of Strings | String) To Symbol(s)
 - `time` (Date) Date in history that you want price data for
+- `tryConversion` (Boolean) By default, if the crypto does not trade directly into the toSymbol requested, BTC will be used for conversion. Set `tryConversion` to `false` to disable using BTC for conversion.
 
 ```js
 const cc = require('cryptocompare')

index.js

@@ -18,10 +18,11 @@ function price (fsym, tsyms, tryConversion) {
   return fetchJSON(url)
 }
 
-function priceHistorical (fsym, tsyms, time) {
+function priceHistorical (fsym, tsyms, time, tryConversion) {
   if (!(time instanceof Date)) throw new Error('time parameter must be an instance of Date.')
   time = Math.floor(time.getTime() / 1000)
   let url = `${baseUrl}pricehistorical?fsym=${fsym}&tsyms=${tsyms}&ts=${time}`
+  if (tryConversion === false) url += '&tryConversion=false'
   // The API returns json with an extra layer of nesting, so remove it
   return fetchJSON(url).then(result => result[fsym])
 }

test/cryptocompare.test.js

@@ -23,10 +23,11 @@ test('price() allows passing a string as the second parameter', t => {
 })
 
 test("price()'s tryConversion=false works", t => {
+  t.plan(1)
   cc.price('LTD', 'USD', false).then(prices => {
     t.end('Promise should not resolve')
   }).catch(e => {
-    t.ok(e, 'Converting LTD to USD fails')
+    t.ok(e.match(/market does not exist/i), 'Converting LTD to USD fails')
     t.end()
   }).catch(t.end)
 })
@@ -43,6 +44,18 @@ test('priceHistorical()', t => {
   }).catch(t.end)
 })
 
+test("priceHistorical()'s tryConversion=false works", t => {
+  t.plan(1)
+  // NOTE: Historical values are hard-coded into this test
+  const timestamp = new Date('2017-01-01')
+  cc.priceHistorical('LTD', 'USD', timestamp, false).then(prices => {
+    t.end('Promise should not resolve')
+  }).catch(e => {
+    t.ok(e.match(/market does not exist/i), 'Converting LTD to USD fails')
+    t.end()
+  }).catch(t.end)
+})
+
 test('error handling', t => {
   cc.price('BTC').then(prices => {
     t.end('Promise should not resolve')