adding comments, tweaking function signatures

MetaMask · May 18, 2021 · 10c5b47 · 10c5b47
1 parent badae43
commit 10c5b47
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Showing 4 changed files with 52 additions and 46 deletions.
diff --git a/src/apis/crypto-compare.test.ts b/src/apis/crypto-compare.test.ts
@@ -27,19 +27,6 @@ describe('CryptoCompare', () => {
     expect(conversionRate).toStrictEqual(2000.42);
   });
 
-  it('should return conversion date', async () => {
-    nock(cryptoCompareHost)
-      .get('/data/price?fsym=ETH&tsyms=CAD')
-      .reply(200, { CAD: 2000.42 });
-
-    const before = Date.now() / 1000;
-    const { conversionDate } = await fetchExchangeRate('CAD', 'ETH');
-    const after = Date.now() / 1000;
-
-    expect(conversionDate).toBeGreaterThanOrEqual(before);
-    expect(conversionDate).toBeLessThanOrEqual(after);
-  });
-
   it('should return CAD conversion rate given lower-cased currency', async () => {
     nock(cryptoCompareHost)
       .get('/data/price?fsym=ETH&tsyms=CAD')
@@ -153,17 +140,6 @@ describe('CryptoCompare', () => {
     );
   });
 
-  it('should return null if either currency inputs are empty', async () => {
-    const { conversionRate, usdConversionRate } = await fetchExchangeRate(
-      '',
-      'ETH',
-      true,
-    );
-
-    expect(conversionRate).toBeNull();
-    expect(usdConversionRate).toBeNull();
-  });
-
   it('should throw an error if either currency is invalid', async () => {
     nock(cryptoCompareHost)
       .get('/data/price?fsym=ETH&tsyms=EUABRT')

diff --git a/src/apis/crypto-compare.ts b/src/apis/crypto-compare.ts
@@ -25,22 +25,21 @@ export async function fetchExchangeRate(
   nativeCurrency: string,
   includeUSDRate?: boolean,
 ): Promise<{
-  conversionDate: number;
-  conversionRate: number | null;
-  usdConversionRate: number | null;
+  conversionRate: number;
+  usdConversionRate: number;
 }> {
-  if (!currency || !nativeCurrency) {
-    return {
-      conversionDate: Date.now() / 1000,
-      conversionRate: null,
-      usdConversionRate: null,
-    };
-  }
-
   const json = await handleFetch(
     getPricingURL(currency, nativeCurrency, includeUSDRate),
   );
 
+  /* 
+  Example expected error response (if pair is not found)
+  {
+    Response: "Error",
+    Message: "cccagg_or_exchange market does not exist for this coin pair (ETH-<NON_EXISTENT_TOKEN>)",
+    HasWarning: false,
+  }
+  */
   if (json.Response === 'Error') {
     throw new Error(json.Message);
   }
@@ -60,7 +59,6 @@ export async function fetchExchangeRate(
   }
 
   return {
-    conversionDate: Date.now() / 1000,
     conversionRate,
     usdConversionRate,
   };

diff --git a/src/assets/CurrencyRateController.test.ts b/src/assets/CurrencyRateController.test.ts
@@ -288,4 +288,35 @@ describe('CurrencyRateController', () => {
     expect(controller.state.conversionRate).toBeNull();
     controller.destroy();
   });
+
+  it('should update conversionRates in state to null if either currentCurrency or nativeCurrency is null', async () => {
+    const realDate = Date.now
+    global.Date.now = jest.fn(() => new Date('2019-04-07T10:20:30Z').getTime())
+
+    const cryptoCompareHost = 'https://min-api.cryptocompare.com';
+    nock(cryptoCompareHost)
+      .get('/data/price?fsym=ETH&tsyms=XYZ')
+      .reply(200, { XYZ: 2000.42 })
+      .persist();
+
+    const messenger = getRestrictedMessenger();
+    const existingState = { currentCurrency: '', nativeCurrency: 'BNB' };
+    const controller = new CurrencyRateController({
+      messenger,
+      state: existingState,
+    });
+
+    await controller.updateExchangeRate();
+
+    expect(controller.state).toEqual({
+      conversionDate: new Date('2019-04-07T10:20:30Z').getTime() / 1000,
+      conversionRate: null,
+      currentCurrency: '',
+      nativeCurrency: 'BNB',
+      pendingCurrentCurrency: null,
+      pendingNativeCurrency: null,
+      usdConversionRate: null,
+    });
+    global.Date.now = realDate;
+  })
 });
diff --git a/src/assets/CurrencyRateController.ts b/src/assets/CurrencyRateController.ts
@@ -196,19 +196,20 @@ export class CurrencyRateController extends BaseController<
       pendingNativeCurrency,
     } = this.state;
 
-    let conversionDate: number = Date.now() / 1000;
+    const conversionDate: number = Date.now() / 1000;
     let conversionRate: number | null = null;
     let usdConversionRate: number | null = null;
     try {
-      ({
-        conversionDate,
-        conversionRate,
-        usdConversionRate,
-      } = await this.fetchExchangeRate(
-        pendingCurrentCurrency || currentCurrency,
-        pendingNativeCurrency || nativeCurrency,
-        this.includeUsdRate,
-      ));
+      if (
+        (pendingCurrentCurrency || currentCurrency) &&
+        (pendingNativeCurrency || nativeCurrency)
+      ) {
+        ({ conversionRate, usdConversionRate } = await this.fetchExchangeRate(
+          pendingCurrentCurrency || currentCurrency,
+          pendingNativeCurrency || nativeCurrency,
+          this.includeUsdRate,
+        ));
+      }
     } catch (error) {
       if (!error.message.includes('market does not exist for this coin pair')) {
         throw error;