Throw on non-List responses to the /log command.

W3C drivers that don't implement the Get Logs command will return an error object rather than a list.

Author: juangj

java/client/src/org/openqa/selenium/remote/RemoteLogs.java

@@ -23,6 +23,7 @@
 import com.google.common.collect.Lists;
 
 import org.openqa.selenium.Beta;
+import org.openqa.selenium.UnsupportedCommandException;
 import org.openqa.selenium.WebDriverException;
 import org.openqa.selenium.logging.LocalLogs;
 import org.openqa.selenium.logging.LogCombiner;
@@ -79,6 +80,9 @@ public LogEntries get(String logType) {
 
   private LogEntries getRemoteEntries(String logType) {
     Object raw = executeMethod.execute(DriverCommand.GET_LOG, ImmutableMap.of(TYPE_KEY, logType));
+    if (!(raw instanceof List)) {
+      throw new UnsupportedCommandException("malformed response to remote logs command");
+    }
     @SuppressWarnings("unchecked")
     List<Map<String, Object>> rawList = (List<Map<String, Object>>) raw;
     List<LogEntry> remoteEntries = Lists.newArrayListWithCapacity(rawList.size());

java/client/test/org/openqa/selenium/remote/RemoteLogsTest.java

@@ -18,6 +18,7 @@
 package org.openqa.selenium.remote;
 
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.fail;
 import static org.mockito.Mockito.verifyNoMoreInteractions;
 import static org.mockito.Mockito.when;
 
@@ -125,6 +126,24 @@ public void canGetServerLogs() {
     verifyNoMoreInteractions(localLogs);
   }
 
+  @Test
+  public void throwsOnBogusRemoteLogsResponse() {
+    when(
+        executeMethod
+            .execute(DriverCommand.GET_LOG, ImmutableMap.of(RemoteLogs.TYPE_KEY, LogType.BROWSER)))
+        .thenReturn(new ImmutableMap.Builder()
+                        .put("error", "unknown method")
+                        .put("message", "Command not found: POST /session/11037/log")
+                        .put("stacktrace", "").build());
+    try {
+      remoteLogs.get(LogType.BROWSER);
+      fail("Should have thrown WebDriverException");
+    } catch (WebDriverException expected) {
+    }
+
+    verifyNoMoreInteractions(localLogs);
+  }
+
   @Test
   public void canGetAvailableLogTypes() {
     List<String> remoteAvailableLogTypes = new ArrayList<>();