Test SocketUtil class

We've had bugs in this parsing/formatting code before, so test it
to ensure it behaves in a way we can predict it should.

Change-Id: I9cc6af7281cba0271ee26357a2400ce647d79783
Signed-off-by: Shawn O. Pearce <sop@google.com>
diff --git a/gerrit-server/src/main/java/com/google/gerrit/server/util/SocketUtil.java b/gerrit-server/src/main/java/com/google/gerrit/server/util/SocketUtil.java
index d7afd95..3d58393 100644
--- a/gerrit-server/src/main/java/com/google/gerrit/server/util/SocketUtil.java
+++ b/gerrit-server/src/main/java/com/google/gerrit/server/util/SocketUtil.java
@@ -23,7 +23,8 @@
 public final class SocketUtil {
   /** True if this InetAddress is a raw IPv6 in dotted quad notation. */
   public static boolean isIPv6(final InetAddress ip) {
-    return ip instanceof Inet6Address && ip.getHostName().equals(ip.getHostAddress());
+    return ip instanceof Inet6Address
+        && ip.getHostName().equals(ip.getHostAddress());
   }
 
   /** Get the name or IP address, or {@code *} if this address is a wildcard IP. */
@@ -41,6 +42,9 @@
   public static String format(final SocketAddress s, final int defaultPort) {
     if (s instanceof InetSocketAddress) {
       final InetSocketAddress addr = (InetSocketAddress) s;
+      if (addr.getPort() == defaultPort) {
+        return safeHostname(hostname(addr));
+      }
       return format(hostname(addr), addr.getPort());
     }
     return s.toString();
@@ -48,10 +52,14 @@
 
   /** Format an address string into {@code host:port} or {@code *:port} syntax. */
   public static String format(String hostname, int port) {
+    return safeHostname(hostname) + ":" + port;
+  }
+
+  private static String safeHostname(String hostname) {
     if (0 <= hostname.indexOf(':')) {
       hostname = "[" + hostname + "]";
     }
-    return hostname + ":" + port;
+    return hostname;
   }
 
   /** Parse an address string such as {@code host:port} or {@code *:port}. */
@@ -64,7 +72,7 @@
       //
       final int hostEnd = desc.indexOf(']');
       if (hostEnd < 0) {
-        throw new IllegalArgumentException("invalid IPv6 representation");
+        throw new IllegalArgumentException("invalid IPv6: " + desc);
       }
 
       hostStr = desc.substring(1, hostEnd);
@@ -89,7 +97,7 @@
       try {
         port = Integer.parseInt(portStr);
       } catch (NumberFormatException e) {
-        throw new IllegalArgumentException("invalid port");
+        throw new IllegalArgumentException("invalid port: " + desc);
       }
     } else {
       port = defaultPort;
@@ -103,7 +111,8 @@
   }
 
   /** Parse and resolve an address string, looking up the IP address. */
-  public static InetSocketAddress resolve(final String desc, final int defaultPort) {
+  public static InetSocketAddress resolve(final String desc,
+      final int defaultPort) {
     final InetSocketAddress addr = parse(desc, defaultPort);
     if (addr.getAddress() != null && addr.getAddress().isAnyLocalAddress()) {
       return addr;
@@ -113,7 +122,7 @@
         final InetAddress host = InetAddress.getByName(addr.getHostName());
         return new InetSocketAddress(host, addr.getPort());
       } catch (UnknownHostException e) {
-        throw new IllegalArgumentException(e.getMessage(), e);
+        throw new IllegalArgumentException("unknown host: " + desc, e);
       }
     }
   }
diff --git a/gerrit-server/src/test/java/com/google/gerrit/server/util/SocketUtilTest.java b/gerrit-server/src/test/java/com/google/gerrit/server/util/SocketUtilTest.java
new file mode 100644
index 0000000..d6004ed
--- /dev/null
+++ b/gerrit-server/src/test/java/com/google/gerrit/server/util/SocketUtilTest.java
@@ -0,0 +1,127 @@
+// Copyright (C) 2009 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.gerrit.server.util;
+
+import static com.google.gerrit.server.util.SocketUtil.format;
+import static com.google.gerrit.server.util.SocketUtil.hostname;
+import static com.google.gerrit.server.util.SocketUtil.isIPv6;
+import static com.google.gerrit.server.util.SocketUtil.parse;
+import static com.google.gerrit.server.util.SocketUtil.resolve;
+import static java.net.InetAddress.getByName;
+import static java.net.InetSocketAddress.createUnresolved;
+
+import junit.framework.TestCase;
+
+import java.net.Inet4Address;
+import java.net.Inet6Address;
+import java.net.InetAddress;
+import java.net.InetSocketAddress;
+import java.net.UnknownHostException;
+
+public class SocketUtilTest extends TestCase {
+  public void testIsIPv6() throws UnknownHostException {
+    final InetAddress ipv6 = getByName("1:2:3:4:5:6:7:8");
+    assertTrue(ipv6 instanceof Inet6Address);
+    assertTrue(isIPv6(ipv6));
+
+    final InetAddress ipv4 = getByName("127.0.0.1");
+    assertTrue(ipv4 instanceof Inet4Address);
+    assertFalse(isIPv6(ipv4));
+  }
+
+  public void testHostname() {
+    assertEquals("*", hostname(new InetSocketAddress(80)));
+    assertEquals("localhost", hostname(new InetSocketAddress("localhost", 80)));
+    assertEquals("foo", hostname(createUnresolved("foo", 80)));
+  }
+
+  public void testFormat() throws UnknownHostException {
+    assertEquals("*:1234", format(new InetSocketAddress(1234), 80));
+    assertEquals("*", format(new InetSocketAddress(80), 80));
+
+    assertEquals("foo:1234", format(createUnresolved("foo", 1234), 80));
+    assertEquals("foo", format(createUnresolved("foo", 80), 80));
+
+    assertEquals("[1:2:3:4:5:6:7:8]:1234",//
+        format(new InetSocketAddress(getByName("1:2:3:4:5:6:7:8"), 1234), 80));
+    assertEquals("[1:2:3:4:5:6:7:8]",//
+        format(new InetSocketAddress(getByName("1:2:3:4:5:6:7:8"), 80), 80));
+
+    assertEquals("localhost:1234",//
+        format(new InetSocketAddress("localhost", 1234), 80));
+    assertEquals("localhost",//
+        format(new InetSocketAddress("localhost", 80), 80));
+  }
+
+  public void testParse() {
+    assertEquals(new InetSocketAddress(1234), parse("*:1234", 80));
+    assertEquals(new InetSocketAddress(80), parse("*", 80));
+    assertEquals(new InetSocketAddress(1234), parse(":1234", 80));
+    assertEquals(new InetSocketAddress(80), parse("", 80));
+
+    assertEquals(createUnresolved("1:2:3:4:5:6:7:8", 1234), //
+        parse("[1:2:3:4:5:6:7:8]:1234", 80));
+    assertEquals(createUnresolved("1:2:3:4:5:6:7:8", 80), //
+        parse("[1:2:3:4:5:6:7:8]", 80));
+
+    assertEquals(createUnresolved("localhost", 1234), //
+        parse("[localhost]:1234", 80));
+    assertEquals(createUnresolved("localhost", 80), //
+        parse("[localhost]", 80));
+
+    assertEquals(createUnresolved("foo.bar.example.com", 1234), //
+        parse("[foo.bar.example.com]:1234", 80));
+    assertEquals(createUnresolved("foo.bar.example.com", 80), //
+        parse("[foo.bar.example.com]", 80));
+
+    try {
+      parse("[:3", 80);
+      fail("did not throw exception");
+    } catch (IllegalArgumentException e) {
+      assertEquals("invalid IPv6: [:3", e.getMessage());
+    }
+
+    try {
+      parse("localhost:A", 80);
+      fail("did not throw exception");
+    } catch (IllegalArgumentException e) {
+      assertEquals("invalid port: localhost:A", e.getMessage());
+    }
+  }
+
+  public void testResolve() throws UnknownHostException {
+    assertEquals(new InetSocketAddress(1234), resolve("*:1234", 80));
+    assertEquals(new InetSocketAddress(80), resolve("*", 80));
+    assertEquals(new InetSocketAddress(1234), resolve(":1234", 80));
+    assertEquals(new InetSocketAddress(80), resolve("", 80));
+
+    assertEquals(new InetSocketAddress(getByName("1:2:3:4:5:6:7:8"), 1234), //
+        resolve("[1:2:3:4:5:6:7:8]:1234", 80));
+    assertEquals(new InetSocketAddress(getByName("1:2:3:4:5:6:7:8"), 80), //
+        resolve("[1:2:3:4:5:6:7:8]", 80));
+
+    assertEquals(new InetSocketAddress(getByName("localhost"), 1234), //
+        resolve("[localhost]:1234", 80));
+    assertEquals(new InetSocketAddress(getByName("localhost"), 80), //
+        resolve("[localhost]", 80));
+
+    try {
+      resolve("invalid.name.localdomain:12", 80);
+      fail("did not throw exception");
+    } catch (IllegalArgumentException e) {
+      assertEquals("unknown host: invalid.name.localdomain:12", e.getMessage());
+    }
+  }
+}