Add a unit test to demonstrate ICU CharsetProvider problems

Also add a single FakeCharsetProvider for unit tests that
does nothing by default, so that we can stub it in for tests
that do care about it and none of our other tests are affected.

Change-Id: I03abb8f1aff53c160935b4cdbeaef764d30f240a

2 files changed, 76 insertions, 36 deletions

diff --git a/harmony-tests/src/test/java/org/apache/harmony/tests/java/nio/charset/CharsetTest.java b/harmony-tests/src/test/java/org/apache/harmony/tests/java/nio/charset/CharsetTest.java
index 01cf40e..2cf278d 100644
--- a/harmony-tests/src/test/java/org/apache/harmony/tests/java/nio/charset/CharsetTest.java
+++ b/harmony-tests/src/test/java/org/apache/harmony/tests/java/nio/charset/CharsetTest.java
@@ -25,15 +25,14 @@ import java.nio.charset.CoderResult;
 import java.nio.charset.IllegalCharsetNameException;
 import java.nio.charset.spi.CharsetProvider;
 import java.nio.charset.UnsupportedCharsetException;
-import java.security.Permission;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.HashSet;
 import java.util.Iterator;
 import java.util.Locale;
 import java.util.Set;
-import java.util.SortedMap;
 import java.util.Vector;
+import libcore.java.nio.charset.SettableCharsetProvider;
 
 import junit.framework.TestCase;
 
@@ -819,51 +818,94 @@ public class CharsetTest extends TestCase {
 
   // Test the method isSupported(String) with charset supported by multiple providers.
   public void testIsSupported_And_ForName_NormalProvider() throws Exception {
-    assertTrue(Charset.isSupported("mockCharset10"));
-    // ignore case problem in mock, intended
-    assertTrue(Charset.isSupported("MockCharset11"));
-    assertTrue(Charset.isSupported("MockCharset12"));
-    assertTrue(Charset.isSupported("MOCKCharset10"));
-    // intended case problem in mock
-    assertTrue(Charset.isSupported("MOCKCharset11"));
-    assertTrue(Charset.isSupported("MOCKCharset12"));
+    SettableCharsetProvider.setDelegate(new MockCharsetProvider());
+    try {
+      assertTrue(Charset.isSupported("mockCharset10"));
+      // ignore case problem in mock, intended
+      assertTrue(Charset.isSupported("MockCharset11"));
+      assertTrue(Charset.isSupported("MockCharset12"));
+      assertTrue(Charset.isSupported("MOCKCharset10"));
+      // intended case problem in mock
+      assertTrue(Charset.isSupported("MOCKCharset11"));
+      assertTrue(Charset.isSupported("MOCKCharset12"));
 
-    assertTrue(Charset.forName("mockCharset10") instanceof MockCharset);
-    assertTrue(Charset.forName("mockCharset11") instanceof MockCharset);
-    assertTrue(Charset.forName("mockCharset12") instanceof MockCharset);
+      assertTrue(Charset.forName("mockCharset10") instanceof MockCharset);
+      assertTrue(Charset.forName("mockCharset11") instanceof MockCharset);
+      assertTrue(Charset.forName("mockCharset12") instanceof MockCharset);
 
-    assertTrue(Charset.forName("mockCharset10") == charset2);
-    // intended case problem in mock
-    Charset.forName("mockCharset11");
-    assertTrue(Charset.forName("mockCharset12") == charset2);
+      assertTrue(Charset.forName("mockCharset10") == charset2);
+      // intended case problem in mock
+      Charset.forName("mockCharset11");
+      assertTrue(Charset.forName("mockCharset12") == charset2);
+    } finally {
+      SettableCharsetProvider.clearDelegate();
+    }
   }
 
   // Test the method availableCharsets() with charset supported by multiple providers.
   public void testAvailableCharsets_NormalProvider() throws Exception {
-    assertTrue(Charset.availableCharsets().containsKey("mockCharset00"));
-    assertTrue(Charset.availableCharsets().containsKey("MOCKCharset00"));
-    assertTrue(Charset.availableCharsets().get("mockCharset00") instanceof MockCharset);
-    assertTrue(Charset.availableCharsets().get("MOCKCharset00") instanceof MockCharset);
-    assertFalse(Charset.availableCharsets().containsKey("mockCharset01"));
-    assertFalse(Charset.availableCharsets().containsKey("mockCharset02"));
+    SettableCharsetProvider.setDelegate(new MockCharsetProvider());
+    try {
+      assertTrue(Charset.availableCharsets().containsKey("mockCharset00"));
+      assertTrue(Charset.availableCharsets().containsKey("MOCKCharset00"));
+      assertTrue(Charset.availableCharsets().get("mockCharset00") instanceof MockCharset);
+      assertTrue(Charset.availableCharsets().get("MOCKCharset00") instanceof MockCharset);
+      assertFalse(Charset.availableCharsets().containsKey("mockCharset01"));
+      assertFalse(Charset.availableCharsets().containsKey("mockCharset02"));
 
-    assertTrue(Charset.availableCharsets().get("mockCharset10") == charset2);
-    assertTrue(Charset.availableCharsets().get("MOCKCharset10") == charset2);
-    assertFalse(Charset.availableCharsets().containsKey("mockCharset11"));
-    assertFalse(Charset.availableCharsets().containsKey("mockCharset12"));
+      assertTrue(Charset.availableCharsets().get("mockCharset10") == charset2);
+      assertTrue(Charset.availableCharsets().get("MOCKCharset10") == charset2);
+      assertFalse(Charset.availableCharsets().containsKey("mockCharset11"));
+      assertFalse(Charset.availableCharsets().containsKey("mockCharset12"));
 
-    assertTrue(Charset.availableCharsets().containsKey("mockCharset10"));
-    assertTrue(Charset.availableCharsets().containsKey("MOCKCharset10"));
-    assertTrue(Charset.availableCharsets().get("mockCharset10") == charset2);
-    assertFalse(Charset.availableCharsets().containsKey("mockCharset11"));
-    assertFalse(Charset.availableCharsets().containsKey("mockCharset12"));
+      assertTrue(Charset.availableCharsets().containsKey("mockCharset10"));
+      assertTrue(Charset.availableCharsets().containsKey("MOCKCharset10"));
+      assertTrue(Charset.availableCharsets().get("mockCharset10") == charset2);
+      assertFalse(Charset.availableCharsets().containsKey("mockCharset11"));
+      assertFalse(Charset.availableCharsets().containsKey("mockCharset12"));
+    } finally {
+      SettableCharsetProvider.clearDelegate();
+    }
   }
 
   // Test the method forName(String) when the charset provider supports a
   // built-in charset.
   public void testForName_DuplicateWithBuiltInCharset() throws Exception {
-    assertFalse(Charset.forName("us-ascii") instanceof MockCharset);
-    assertFalse(Charset.availableCharsets().get("us-ascii") instanceof MockCharset);
+    SettableCharsetProvider.setDelegate(new MockCharsetProviderASCII());
+    try {
+      assertFalse(Charset.forName("us-ascii") instanceof MockCharset);
+      assertFalse(Charset.availableCharsets().get("us-ascii") instanceof MockCharset);
+    } finally {
+      SettableCharsetProvider.clearDelegate();
+    }
+  }
+
+  // Fails on Android with a StackOverflowException.
+  public void testForName_withProviderWithRecursiveCall() throws Exception {
+    SettableCharsetProvider.setDelegate(new MockCharsetProviderWithRecursiveCall());
+    try {
+      Charset.forName("poop");
+      fail();
+    } catch (UnsupportedCharsetException expected) {
+    } finally {
+      SettableCharsetProvider.clearDelegate();
+    }
+  }
+
+  public static class MockCharsetProviderWithRecursiveCall extends CharsetProvider {
+      @Override
+      public Iterator<Charset> charsets() {
+          return null;
+      }
+
+      @Override
+      public Charset charsetForName(String charsetName) {
+          if (Charset.isSupported(charsetName)) {
+              return Charset.forName(charsetName);
+          }
+
+          return null;
+      }
   }
 
   public static class MockCharsetProvider extends CharsetProvider {
diff --git a/harmony-tests/src/test/resources/META-INF/services/java.nio.charset.spi.CharsetProvider b/harmony-tests/src/test/resources/META-INF/services/java.nio.charset.spi.CharsetProvider
deleted file mode 100644
index 9cc124a..0000000
--- a/harmony-tests/src/test/resources/META-INF/services/java.nio.charset.spi.CharsetProvider
+++ /dev/null
@@ -1,2 +0,0 @@
-org.apache.harmony.tests.java.nio.charset.CharsetTest$MockCharsetProvider
-org.apache.harmony.tests.java.nio.charset.CharsetTest$MockCharsetProviderASCII