FIX: round fiat currencies to 2 significant digits

android/app/build.gradle

@@ -108,7 +108,7 @@ def enableProguardInReleaseBuilds = false
  * give correct results when using with locales other than en-US.  Note that
  * this variant is about 6MiB larger per architecture than default.
  */
-def jscFlavor = 'org.webkit:android-jsc:+'
+def jscFlavor = 'org.webkit:android-jsc-intl:+'
 
 /**
  * Whether to enable the Hermes VM.

currency.js

@@ -86,20 +86,21 @@ function satoshiToLocalCurrency(satoshi) {
     return '...';
   }
 
-  let b = new BigNumber(satoshi);
-  b = b
-    .dividedBy(100000000)
-    .multipliedBy(exchangeRates['BTC_' + preferredFiatCurrency.endPointKey])
-    .toString(10);
-  b = parseFloat(b).toFixed(2);
+  let b = new BigNumber(satoshi).dividedBy(100000000).multipliedBy(exchangeRates['BTC_' + preferredFiatCurrency.endPointKey]);
+
+  if (b.isGreaterThanOrEqualTo(1) || b.isLessThanOrEqualTo(-1)) {
+    b = b.toFixed(2);
+  } else {
+    b = b.toPrecision(2);
+  }
 
   let formatter;
-
   try {
     formatter = new Intl.NumberFormat(preferredFiatCurrency.locale, {
       style: 'currency',
       currency: preferredFiatCurrency.endPointKey,
       minimumFractionDigits: 2,
+      maximumFractionDigits: 8,
     });
   } catch (error) {
     console.warn(error);
@@ -108,6 +109,7 @@ function satoshiToLocalCurrency(satoshi) {
       style: 'currency',
       currency: preferredFiatCurrency.endPointKey,
       minimumFractionDigits: 2,
+      maximumFractionDigits: 8,
     });
   }
 
@@ -135,3 +137,4 @@ module.exports.satoshiToBTC = satoshiToBTC;
 module.exports.BTCToLocalCurrency = BTCToLocalCurrency;
 module.exports.setPrefferedCurrency = setPrefferedCurrency;
 module.exports.getPreferredCurrency = getPreferredCurrency;
+module.exports.exchangeRates = exchangeRates; // export it to mock data in tests

index.js

@@ -1,5 +1,3 @@
-import 'intl';
-import 'intl/locale-data/jsonp/en';
 import React from 'react';
 import './shim.js';
 import { AppRegistry } from 'react-native';

package-lock.json

@@ -8011,11 +8011,6 @@
         "side-channel": "^1.0.2"
       }
     },
-    "intl": {
-      "version": "1.2.5",
-      "resolved": "https://registry.npmjs.org/intl/-/intl-1.2.5.tgz",
-      "integrity": "sha1-giRKIZDE5Bn4Nx9ao02qNCDiq94="
-    },
     "invariant": {
       "version": "2.2.4",
       "resolved": "https://registry.npmjs.org/invariant/-/invariant-2.2.4.tgz",

package.json

@@ -91,7 +91,6 @@
     "eslint-plugin-standard": "4.0.1",
     "events": "1.1.1",
     "frisbee": "3.1.2",
-    "intl": "1.2.5",
     "lottie-react-native": "3.1.1",
     "metro-react-native-babel-preset": "0.59.0",
     "node-libs-react-native": "1.2.0",

tests/integration/Currency.test.js

@@ -30,4 +30,32 @@ describe('currency', () => {
     cur = JSON.parse(await AsyncStorage.getItem(AppStorage.EXCHANGE_RATES));
     assert.ok(cur.BTC_EUR > 0);
   });
+
+  it('formats everything correctly', async () => {
+    const currency = require('../../currency');
+    await currency.setPrefferedCurrency(FiatUnit.USD);
+    await currency.startUpdater();
+    currency.exchangeRates.BTC_USD = 10000;
+    assert.strictEqual(currency.satoshiToLocalCurrency(1), '$0.0001');
+    assert.strictEqual(currency.satoshiToLocalCurrency(-1), '-$0.0001');
+    assert.strictEqual(currency.satoshiToLocalCurrency(123), '$0.012');
+    assert.strictEqual(currency.satoshiToLocalCurrency(146), '$0.015');
+    assert.strictEqual(currency.satoshiToLocalCurrency(123456789), '$12,345.68');
+
+    assert.strictEqual(currency.BTCToLocalCurrency(1), '$10,000.00');
+    assert.strictEqual(currency.BTCToLocalCurrency(-1), '-$10,000.00');
+    assert.strictEqual(currency.BTCToLocalCurrency(1.00000001), '$10,000.00');
+    assert.strictEqual(currency.BTCToLocalCurrency(1.0000123), '$10,000.12');
+    assert.strictEqual(currency.BTCToLocalCurrency(1.0000146), '$10,000.15');
+
+    assert.strictEqual(currency.satoshiToBTC(1), '0.00000001');
+    assert.strictEqual(currency.satoshiToBTC(-1), '-0.00000001');
+    assert.strictEqual(currency.satoshiToBTC(100000000), '1');
+    assert.strictEqual(currency.satoshiToBTC(123456789123456789), '1234567891.2345678');
+
+    await currency.setPrefferedCurrency(FiatUnit.JPY);
+    await currency.startUpdater();
+    currency.exchangeRates.BTC_JPY = 1043740.8614;
+    assert.strictEqual(currency.satoshiToLocalCurrency(1), '¥0.01');
+  });
 });