Address PR feedback

PicnicSupermarket · Dec 16, 2023 · 2695c4d · 2695c4d
1 parent 532dfe6
commit 2695c4d
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Showing 2 changed files with 15 additions and 2 deletions.
diff --git a/...one-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/CanonicalClassNameUsage.java b/...one-contrib/src/main/java/tech/picnic/errorprone/bugpatterns/CanonicalClassNameUsage.java
@@ -3,7 +3,12 @@
 import static com.google.errorprone.BugPattern.LinkType.CUSTOM;
 import static com.google.errorprone.BugPattern.SeverityLevel.WARNING;
 import static com.google.errorprone.BugPattern.StandardTags.FRAGILE_CODE;
+import static com.google.errorprone.matchers.Matchers.allOf;
+import static com.google.errorprone.matchers.Matchers.anything;
+import static com.google.errorprone.matchers.Matchers.classLiteral;
 import static com.google.errorprone.matchers.Matchers.instanceMethod;
+import static com.google.errorprone.matchers.Matchers.receiverOfInvocation;
+import static com.google.errorprone.matchers.Matchers.toType;
 import static tech.picnic.errorprone.bugpatterns.util.Documentation.BUG_PATTERNS_BASE_URL;
 
 import com.google.auto.service.AutoService;
@@ -29,8 +34,11 @@
  *
  * <p>For top-level types these two methods generally return the same result, but for nested types
  * the former separates identifiers using a dollar sign ({@code $}) rather than a dot ({@code .}).
+ *
+ * @implNote This check currently only flags {@link Class#getName()} invocations on class literals,
+ *     and doesn't flag method references. This avoids false positives, such as suggesting use of
+ *     {@link Class#getCanonicalName()} in contexts where the canonical name is {@code null}.
  */
-// XXX: This check currently doesn't flag `Class::getName` method references.
 @AutoService(BugChecker.class)
 @BugPattern(
     summary = "This code should likely use the type's canonical name",
@@ -42,7 +50,11 @@ public final class CanonicalClassNameUsage extends BugChecker
     implements MethodInvocationTreeMatcher {
   private static final long serialVersionUID = 1L;
   private static final Matcher<ExpressionTree> GET_NAME_INVOCATION =
-      instanceMethod().onExactClass(Class.class.getCanonicalName()).named("getName");
+      toType(
+          MethodInvocationTree.class,
+          allOf(
+              receiverOfInvocation(classLiteral(anything())),
+              instanceMethod().onExactClass(Class.class.getCanonicalName()).named("getName")));
   private static final Pattern CANONICAL_NAME_USING_TYPES =
       Pattern.compile("(com\\.google\\.errorprone|tech\\.picnic\\.errorprone)\\..*");
 

diff --git a/...contrib/src/test/java/tech/picnic/errorprone/bugpatterns/CanonicalClassNameUsageTest.java b/...contrib/src/test/java/tech/picnic/errorprone/bugpatterns/CanonicalClassNameUsageTest.java
@@ -29,6 +29,7 @@ void identification() {
             "    instanceMethod().onExactClass(A.class.getCanonicalName());",
             "    MoreTypes.type(A.class.getCanonicalName());",
             "    MoreTypes.type(A.class.getCanonicalName() + \".SubType\");",
+            "    instanceMethod().onExactClass(new Object() {}.getClass().getName());",
             "    instanceMethod().onExactClass(methodInUnnamedPackage(A.class.getName()));",
             "    // BUG: Diagnostic contains:",
             "    instanceMethod().onExactClass(A.class.getName());",