Moved static equals & instance equals matchers to Matchers.java to en…

…able code reuse. RELNOTES: n/a ------------- Created by MOE: https://github.com/google/moe MOE_MIGRATED_REVID=203014586
google · Jul 13, 2018 · 5698d02 · 5698d02
1 parent fd60099
commit 5698d02
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Showing 2 changed files with 45 additions and 31 deletions.
diff --git a/check_api/src/main/java/com/google/errorprone/matchers/Matchers.java b/check_api/src/main/java/com/google/errorprone/matchers/Matchers.java
@@ -16,6 +16,7 @@
 
 package com.google.errorprone.matchers;
 
+import static com.google.errorprone.suppliers.Suppliers.BOOLEAN_TYPE;
 import static com.google.errorprone.suppliers.Suppliers.typeFromClass;
 import static com.google.errorprone.util.ASTHelpers.stripParentheses;
 
@@ -1492,4 +1493,38 @@ private static String getPackageFullName(VisitorState state) {
     JCCompilationUnit compilationUnit = (JCCompilationUnit) state.getPath().getCompilationUnit();
     return compilationUnit.packge.fullname.toString();
   }
+
+  /**
+   * Matches an invocation of a recognized static object equality method such as {@link
+   * java.util.Objects#equals}. These are simple facades to {@link Object#equals} that accept null
+   * for either argument.
+   */
+  public static Matcher<MethodInvocationTree> staticEqualsInvocation() {
+    return anyOf(
+        allOf(
+            staticMethod()
+                .onClass("android.support.v4.util.ObjectsCompat")
+                .named("equals")
+                .withParameters("java.lang.Object", "java.lang.Object"),
+            isSameType(BOOLEAN_TYPE)),
+        allOf(
+            staticMethod()
+                .onClass("java.util.Objects")
+                .named("equals")
+                .withParameters("java.lang.Object", "java.lang.Object"),
+            isSameType(BOOLEAN_TYPE)),
+        allOf(
+            staticMethod()
+                .onClass("com.google.common.base.Objects")
+                .named("equal")
+                .withParameters("java.lang.Object", "java.lang.Object"),
+            isSameType(BOOLEAN_TYPE)));
+  }
+
+  /** Matches calls to the method {link Object#equals(Object)} or any override of that method. */
+  public static Matcher<MethodInvocationTree> instanceEqualsInvocation() {
+    return allOf(
+        instanceMethod().anyClass().named("equals").withParameters("java.lang.Object"),
+        isSameType(BOOLEAN_TYPE));
+  }
 }
diff --git a/core/src/main/java/com/google/errorprone/bugpatterns/EqualsIncompatibleType.java b/core/src/main/java/com/google/errorprone/bugpatterns/EqualsIncompatibleType.java
@@ -18,13 +18,12 @@
 
 import static com.google.errorprone.BugPattern.Category.JDK;
 import static com.google.errorprone.BugPattern.SeverityLevel.WARNING;
-import static com.google.errorprone.matchers.Matchers.allOf;
 import static com.google.errorprone.matchers.Matchers.anyOf;
+import static com.google.errorprone.matchers.Matchers.instanceEqualsInvocation;
 import static com.google.errorprone.matchers.Matchers.instanceMethod;
-import static com.google.errorprone.matchers.Matchers.isSameType;
+import static com.google.errorprone.matchers.Matchers.staticEqualsInvocation;
 import static com.google.errorprone.matchers.Matchers.staticMethod;
 import static com.google.errorprone.matchers.Matchers.toType;
-import static com.google.errorprone.suppliers.Suppliers.BOOLEAN_TYPE;
 
 import com.google.auto.value.AutoValue;
 import com.google.common.base.Predicate;
@@ -60,31 +59,11 @@
     category = JDK,
     severity = WARNING)
 public class EqualsIncompatibleType extends BugChecker implements MethodInvocationTreeMatcher {
-  private static final Matcher<MethodInvocationTree> STATIC_EQUALS_INVOCATION_MATCHER =
-      anyOf(
-          allOf(
-              staticMethod()
-                  .onClass("android.support.v4.util.ObjectsCompat")
-                  .named("equals")
-                  .withParameters("java.lang.Object", "java.lang.Object"),
-              isSameType(BOOLEAN_TYPE)),
-          allOf(
-              staticMethod()
-                  .onClass("java.util.Objects")
-                  .named("equals")
-                  .withParameters("java.lang.Object", "java.lang.Object"),
-              isSameType(BOOLEAN_TYPE)),
-          allOf(
-              staticMethod()
-                  .onClass("com.google.common.base.Objects")
-                  .named("equal")
-                  .withParameters("java.lang.Object", "java.lang.Object"),
-              isSameType(BOOLEAN_TYPE)));
-
-  private static final Matcher<MethodInvocationTree> INSTANCE_EQUALS_INVOCATION_MATCHER =
-      allOf(
-          instanceMethod().anyClass().named("equals").withParameters("java.lang.Object"),
-          isSameType(BOOLEAN_TYPE));
+  private static final Matcher<MethodInvocationTree> STATIC_EQUALS_MATCHER =
+      staticEqualsInvocation();
+
+  private static final Matcher<MethodInvocationTree> INSTANCE_EQUALS_MATCHER =
+      instanceEqualsInvocation();
 
   private static final Matcher<Tree> ASSERT_FALSE_MATCHER =
       toType(
@@ -96,8 +75,8 @@ public class EqualsIncompatibleType extends BugChecker implements MethodInvocati
   @Override
   public Description matchMethodInvocation(
       MethodInvocationTree invocationTree, final VisitorState state) {
-    if (!STATIC_EQUALS_INVOCATION_MATCHER.matches(invocationTree, state)
-        && !INSTANCE_EQUALS_INVOCATION_MATCHER.matches(invocationTree, state)) {
+    if (!STATIC_EQUALS_MATCHER.matches(invocationTree, state)
+        && !INSTANCE_EQUALS_MATCHER.matches(invocationTree, state)) {
       return Description.NO_MATCH;
     }
 
@@ -110,7 +89,7 @@ public Description matchMethodInvocation(
     // to this method.
     Type argumentType;
 
-    if (STATIC_EQUALS_INVOCATION_MATCHER.matches(invocationTree, state)) {
+    if (STATIC_EQUALS_MATCHER.matches(invocationTree, state)) {
       receiverType = ASTHelpers.getType(invocationTree.getArguments().get(0));
       argumentType = ASTHelpers.getType(invocationTree.getArguments().get(1));
     } else {