fix NumberFormat.resolvedOptions on Android (#1565)

Summary:
A typo currently leads to wrong results for `NumberFormat.resolvedOptions()`: `minimumSignificantDigits` and `maximumSignificantDigits` are interchanged.

This PR fixes that and adds tests.

Pull Request resolved: #1565

Test Plan: Added unit tests.

Reviewed By: dannysu

Differential Revision: D65822468

Pulled By: neildhar

fbshipit-source-id: bb5ba5d6257b9c6d7257fb9494b988b175855d77

android/intltest/java/com/facebook/hermes/test/HermesIntlAndroidTest.java

@@ -48,6 +48,18 @@ public void testNumberFormatFractionDigitsFromAsset() throws IOException {
     }
   }
 
+  @Test
+  public void testNumberFormatSignificantDigitsFromAsset() throws IOException {
+    AssetManager assets =
+        InstrumentationRegistry.getInstrumentation().getTargetContext().getAssets();
+    InputStream is = assets.open("number-format-significant-digits.js");
+    String script =
+        new BufferedReader(new InputStreamReader(is)).lines().collect(Collectors.joining("\n"));
+    try (JSRuntime rt = JSRuntime.makeHermesRuntime()) {
+      rt.evaluateJavaScript(script);
+    }
+  }
+
   @Test
   public void testDateTimeFormat() {
     try (JSRuntime rt = JSRuntime.makeHermesRuntime()) {

lib/Platform/Intl/java/com/facebook/hermes/intl/NumberFormat.java

@@ -626,10 +626,10 @@ public Map<String, Object> resolvedOptions() throws JSRangeErrorException {
 
     if (mRoundingType == IPlatformNumberFormatter.RoundingType.SIGNIFICANT_DIGITS) {
       if (mResolvedMaximumSignificantDigits != -1)
-        finalResolvedOptions.put("minimumSignificantDigits", mResolvedMaximumSignificantDigits);
+        finalResolvedOptions.put("maximumSignificantDigits", mResolvedMaximumSignificantDigits);
 
       if (mResolvedMinimumSignificantDigits != -1)
-        finalResolvedOptions.put("maximumSignificantDigits", mResolvedMinimumSignificantDigits);
+        finalResolvedOptions.put("minimumSignificantDigits", mResolvedMinimumSignificantDigits);
 
     } else if (mRoundingType == IPlatformNumberFormatter.RoundingType.FRACTION_DIGITS) {
 

test/hermes/intl/number-format-significant-digits.js

@@ -0,0 +1,65 @@
+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+// RUN: %hermes %s
+// REQUIRES: intl
+
+function assert(pred, str) {
+  if (!pred) {
+    throw new Error('assertion failed' + (str === undefined ? '' : (': ' + str)));
+  }
+}
+
+let resolvedOptions;
+
+resolvedOptions = new Intl.NumberFormat('en-US', {style: 'currency', currency: 'USD' }).resolvedOptions();
+assert(resolvedOptions.minimumSignificantDigits === undefined);
+assert(resolvedOptions.maximumSignificantDigits === undefined);
+
+//
+// Validate minimumSignificantDigits logic
+//
+try { new Intl.NumberFormat('en-US', {style: 'currency', currency: 'USD', minimumSignificantDigits: -1 }) }
+catch (e) { assert(e.message.includes('minimumSignificantDigits value is invalid.')) }
+
+try { new Intl.NumberFormat('en-US', {style: 'currency', currency: 'USD', minimumSignificantDigits: 22 }) }
+catch (e) { assert(e.message.includes('minimumSignificantDigits value is invalid.')) }
+
+resolvedOptions = new Intl.NumberFormat('en-US', {style: 'currency', currency: 'USD', minimumSignificantDigits: 1 }).resolvedOptions();
+assert(resolvedOptions.minimumSignificantDigits === 1);
+assert(resolvedOptions.maximumSignificantDigits === 21);
+
+resolvedOptions = new Intl.NumberFormat('en-US', {style: 'currency', currency: 'USD', minimumSignificantDigits: 21 }).resolvedOptions();
+assert(resolvedOptions.minimumSignificantDigits === 21);
+assert(resolvedOptions.maximumSignificantDigits === 21);
+
+//
+// Validate maximumSignificantDigits logic
+//
+try { new Intl.NumberFormat('en-US', {style: 'currency', currency: 'USD', maximumSignificantDigits: -1 }) }
+catch (e) { assert(e.message.includes('maximumSignificantDigits value is invalid.')) }
+
+try { new Intl.NumberFormat('en-US', {style: 'currency', currency: 'USD', maximumSignificantDigits: 22 }) }
+catch (e) { assert(e.message.includes('maximumSignificantDigits value is invalid.')) }
+
+resolvedOptions = new Intl.NumberFormat('en-US', {style: 'currency', currency: 'USD', maximumSignificantDigits: 1 }).resolvedOptions();
+assert(resolvedOptions.minimumSignificantDigits === 1);
+assert(resolvedOptions.maximumSignificantDigits === 1);
+
+resolvedOptions = new Intl.NumberFormat('en-US', {style: 'currency', currency: 'USD', maximumSignificantDigits: 21 }).resolvedOptions();
+assert(resolvedOptions.minimumSignificantDigits === 1);
+assert(resolvedOptions.maximumSignificantDigits === 21);
+
+//
+// Validate when both are set
+//
+try { new Intl.NumberFormat('en-US', {style: 'currency', currency: 'USD', minimumSignificantDigits: 5, maximumSignificantDigits: 2 }) }
+catch (e) { assert(e.message.includes('maximumSignificantDigits value is invalid.')) }
+
+resolvedOptions = new Intl.NumberFormat('en-US', {style: 'currency', currency: 'USD', minimumSignificantDigits: 3, maximumSignificantDigits: 5 }).resolvedOptions();
+assert(resolvedOptions.minimumSignificantDigits === 3);
+assert(resolvedOptions.maximumSignificantDigits === 5);