Firestore: Migrate unit tests to assertThrows() (#3562)

Author: dconeybe

firebase-firestore/src/test/java/com/google/firebase/firestore/FieldPathTest.java

@@ -16,6 +16,7 @@
 
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertNotEquals;
+import static org.junit.Assert.assertThrows;
 
 import org.junit.Test;
 import org.junit.runner.RunWith;
@@ -32,24 +33,24 @@ public void pathWithArray() {
     assertEquals("a.b.c", fieldPath.toString());
   }
 
-  @Test(expected = IllegalArgumentException.class)
+  @Test
   public void emptyPathIsInvalid() {
-    FieldPath.fromDotSeparatedPath("");
+    assertThrows(IllegalArgumentException.class, () -> FieldPath.fromDotSeparatedPath(""));
   }
 
-  @Test(expected = IllegalArgumentException.class)
+  @Test
   public void emptyFirstSegmentIsInvalid() {
-    FieldPath.fromDotSeparatedPath(".a");
+    assertThrows(IllegalArgumentException.class, () -> FieldPath.fromDotSeparatedPath(".a"));
   }
 
-  @Test(expected = IllegalArgumentException.class)
+  @Test
   public void emptyLastSegmentIsInvalid() {
-    FieldPath.fromDotSeparatedPath("a.");
+    assertThrows(IllegalArgumentException.class, () -> FieldPath.fromDotSeparatedPath("a."));
   }
 
-  @Test(expected = IllegalArgumentException.class)
+  @Test
   public void emptyMiddleSegmentIsInvalid() {
-    FieldPath.fromDotSeparatedPath("a..b");
+    assertThrows(IllegalArgumentException.class, () -> FieldPath.fromDotSeparatedPath("a..b"));
   }
 
   @Test

firebase-firestore/src/test/java/com/google/firebase/firestore/bundle/BundleReaderTest.java

@@ -21,6 +21,7 @@
 import static com.google.firebase.firestore.testutil.TestUtil.version;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertThrows;
 
 import com.google.firebase.firestore.core.Query;
 import com.google.firebase.firestore.core.Target;
@@ -219,55 +220,59 @@ public void testReadsWithoutDocumentOrQuery() throws IOException, JSONException
     verifyAllElements(bundleReader);
   }
 
-  @Test(expected = IllegalArgumentException.class)
+  @Test
   public void testThrowsWithoutLengthPrefix() throws IOException, JSONException {
     String bundle = "{metadata: 'no length prefix' }";
 
     BundleReader bundleReader =
         new BundleReader(SERIALIZER, new ByteArrayInputStream(bundle.getBytes(UTF8_CHARSET)));
 
-    bundleReader.getBundleMetadata();
+    assertThrows(IllegalArgumentException.class, () -> bundleReader.getBundleMetadata());
   }
 
-  @Test(expected = IllegalArgumentException.class)
+  @Test
   public void testThrowsWithMissingBrackets() throws IOException, JSONException {
     String bundle = "3abc";
 
     BundleReader bundleReader =
         new BundleReader(SERIALIZER, new ByteArrayInputStream(bundle.getBytes(UTF8_CHARSET)));
-    bundleReader.getBundleMetadata();
+
+    assertThrows(IllegalArgumentException.class, () -> bundleReader.getBundleMetadata());
   }
 
-  @Test(expected = JSONException.class)
+  @Test
   public void testThrowsWithInvalidJSON() throws IOException, JSONException {
     String bundle = "3{abc}";
 
     BundleReader bundleReader =
         new BundleReader(SERIALIZER, new ByteArrayInputStream(bundle.getBytes(UTF8_CHARSET)));
-    bundleReader.getBundleMetadata();
+
+    assertThrows(JSONException.class, () -> bundleReader.getBundleMetadata());
   }
 
-  @Test(expected = IllegalArgumentException.class)
+  @Test
   public void testThrowsWhenSecondElementIsMissing() throws IOException, JSONException {
     TestBundleBuilder bundleBuilder = new TestBundleBuilder(TEST_PROJECT);
     String bundle =
         bundleBuilder.build("bundle-1", /* createTimeMicros= */ 6000000L, /* version= */ 1) + "foo";
 
     BundleReader bundleReader =
         new BundleReader(SERIALIZER, new ByteArrayInputStream(bundle.getBytes(UTF8_CHARSET)));
-    bundleReader.getNextElement();
+
+    assertThrows(IllegalArgumentException.class, () -> bundleReader.getNextElement());
   }
 
-  @Test(expected = IllegalArgumentException.class)
+  @Test
   public void testThrowsWhenBundleDoesNotContainEnoughData() throws IOException, JSONException {
     String bundle = "3{}";
 
     BundleReader bundleReader =
         new BundleReader(SERIALIZER, new ByteArrayInputStream(bundle.getBytes(UTF8_CHARSET)));
-    bundleReader.getBundleMetadata();
+
+    assertThrows(IllegalArgumentException.class, () -> bundleReader.getBundleMetadata());
   }
 
-  @Test(expected = IllegalArgumentException.class)
+  @Test
   public void testWhenFirstElementIsNotBundleMetadata() throws IOException, JSONException {
     String json =
         String.format(
@@ -283,7 +288,7 @@ public void testWhenFirstElementIsNotBundleMetadata() throws IOException, JSONEx
     BundleReader bundleReader =
         new BundleReader(SERIALIZER, new ByteArrayInputStream(bundle.getBytes(UTF8_CHARSET)));
 
-    bundleReader.getBundleMetadata();
+    assertThrows(IllegalArgumentException.class, () -> bundleReader.getBundleMetadata());
   }
 
   @Test

firebase-firestore/src/test/java/com/google/firebase/firestore/bundle/BundleSerializerTest.java

@@ -20,6 +20,7 @@
 import static com.google.firebase.firestore.testutil.TestUtil.orderBy;
 import static java.util.Arrays.asList;
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertThrows;
 
 import com.google.firebase.firestore.core.Query;
 import com.google.firebase.firestore.core.Target;
@@ -596,32 +597,32 @@ public void testDecodesEndBeforeQuery() throws JSONException {
     assertDecodesNamedQuery(json, query);
   }
 
-  @Test(expected = IllegalArgumentException.class)
+  @Test
   public void testDoesNotDecodeOffset() throws JSONException {
     String json = "{ from: [ { collectionId: 'coll' } ], offset: 5 }";
     Query query = TestUtil.query("coll");
-    assertDecodesNamedQuery(json, query);
+    assertThrows(IllegalArgumentException.class, () -> assertDecodesNamedQuery(json, query));
   }
 
-  @Test(expected = IllegalArgumentException.class)
+  @Test
   public void testDoesNotDecodeSelect() throws JSONException {
     String json = "{ from: [ { collectionId: 'coll' } ], select: [] }";
     Query query = TestUtil.query("coll");
-    assertDecodesNamedQuery(json, query);
+    assertThrows(IllegalArgumentException.class, () -> assertDecodesNamedQuery(json, query));
   }
 
-  @Test(expected = IllegalArgumentException.class)
+  @Test
   public void testDoesNotDecodeMissingCollection() throws JSONException {
     String json = "{ from: [ ] }";
     Query query = TestUtil.query("coll");
-    assertDecodesNamedQuery(json, query);
+    assertThrows(IllegalArgumentException.class, () -> assertDecodesNamedQuery(json, query));
   }
 
-  @Test(expected = IllegalArgumentException.class)
+  @Test
   public void testDoesNotDecodeMultipleCollections() throws JSONException {
     String json = "{ from: [ { collectionId: 'c1' }, { collectionId: 'c2' } ] }";
     Query query = TestUtil.query("coll");
-    assertDecodesNamedQuery(json, query);
+    assertThrows(IllegalArgumentException.class, () -> assertDecodesNamedQuery(json, query));
   }
 
   // BundleMetadata tests

firebase-firestore/src/test/java/com/google/firebase/firestore/model/DocumentKeyTest.java

@@ -17,9 +17,11 @@
 import static java.util.Arrays.asList;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertNotEquals;
+import static org.junit.Assert.assertThrows;
 
 import com.google.firebase.firestore.testutil.ComparatorTester;
 import java.util.Collections;
+import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.robolectric.RobolectricTestRunner;
@@ -57,8 +59,9 @@ public void testComparison() {
         .testCompare();
   }
 
-  @Test(expected = Throwable.class)
+  @Test
   public void testUnevenNumberOfSegmentsAreRejected() {
-    DocumentKey.fromSegments(Collections.singletonList("a"));
+    List<String> segments = Collections.singletonList("a");
+    assertThrows(Throwable.class, () -> DocumentKey.fromSegments(segments));
   }
 }