Done with getType -- create arbitrary Types for matchers

core/src/main/java/com/google/errorprone/VisitorState.java

@@ -154,6 +154,11 @@ public Name getName(String nameStr) {
    * Given the string representation of a simple (non-array, non-generic) type, return the
    * matching Type.
    *
+   * <p>If this method returns null, the compiler has not seen this type yet, which means that if
+   * you are comparing other types to this for equality or the subtype relation, your result would
+   * always be false even if it could create the type.  Thus it might be best to bail out early in
+   * your matcher if this method returns null on your type of interest.
+   *
    * @param typeStr The canonical string representation of a simple type (e.g., "java.lang.Object")
    * @return The Type that corresponds to the string, or null if it cannot be found
    */
@@ -258,8 +263,4 @@ private static boolean isPrimitiveType(String typeStr) {
   private interface NameLookupStrategy {
     Name fromString(Context context, String nameStr);
   }
-
-  public class TypeBuilder {
-
-  }
 }

core/src/main/java/com/google/errorprone/bugpatterns/ArrayEquals.java

@@ -33,8 +33,6 @@
 import static com.google.errorprone.matchers.Matchers.*;
 
 /**
- * TODO(eaftan): tests -- more positive cases, start negative cases
- *
  * @author eaftan@google.com (Eddie Aftandilian)
  */
 @BugPattern(name = "ArrayEquals",
@@ -75,11 +73,11 @@ public Description describe(MethodInvocationTree t, VisitorState state) {
   }
 
   public static class Scanner extends com.google.errorprone.Scanner {
-    public DescribingMatcher<MethodInvocationTree> matcher = new ArrayEquals();
+    public DescribingMatcher<MethodInvocationTree> scannerMatcher = new ArrayEquals();
 
     @Override
     public Void visitMethodInvocation(MethodInvocationTree node, VisitorState visitorState) {
-      evaluateMatch(node, visitorState, matcher);
+      evaluateMatch(node, visitorState, scannerMatcher);
       return super.visitMethodInvocation(node, visitorState);
     }
   }