UnusedMethod: Add support for excluding annotations from analysis

PicnicSupermarket · Aug 17, 2022 · 70431bb · 70431bb
1 parent 973313f
commit 70431bb
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Showing 2 changed files with 31 additions and 2 deletions.
diff --git a/core/src/main/java/com/google/errorprone/bugpatterns/UnusedMethod.java b/core/src/main/java/com/google/errorprone/bugpatterns/UnusedMethod.java
@@ -45,6 +45,7 @@
 import com.google.common.collect.ImmutableListMultimap;
 import com.google.common.collect.ImmutableSet;
 import com.google.errorprone.BugPattern;
+import com.google.errorprone.ErrorProneFlags;
 import com.google.errorprone.VisitorState;
 import com.google.errorprone.bugpatterns.BugChecker.CompilationUnitTreeMatcher;
 import com.google.errorprone.fixes.SuggestedFix;
@@ -147,6 +148,16 @@ public final class UnusedMethod extends BugChecker implements CompilationUnitTre
   /** The set of types exempting a type that is extending or implementing them. */
   private static final ImmutableSet<String> EXEMPTING_SUPER_TYPES = ImmutableSet.of();
 
+  private final ImmutableSet<String> exemptMethodAnnotations;
+
+  public UnusedMethod(ErrorProneFlags errorProneFlags) {
+    ImmutableSet.Builder<String> exemptMethodAnnotations = ImmutableSet.builder();
+    errorProneFlags
+        .getList("UnusedMethod:ExemptMethodAnnotations")
+        .ifPresent(exemptMethodAnnotations::addAll);
+    this.exemptMethodAnnotations = exemptMethodAnnotations.build();
+  }
+
   @Override
   public Description matchCompilationUnit(CompilationUnitTree tree, VisitorState state) {
     // Map of symbols to method declarations. Initially this is a map of all of the methods. As we
@@ -433,14 +444,16 @@ public Void visitMethod(MethodTree tree, Void unused) {
    * Looks at the list of {@code annotations} and see if there is any annotation which exists {@code
    * exemptingAnnotations}.
    */
-  private static boolean exemptedByAnnotation(List<? extends AnnotationTree> annotations) {
+  private boolean exemptedByAnnotation(List<? extends AnnotationTree> annotations) {
     for (AnnotationTree annotation : annotations) {
       Type annotationType = getType(annotation);
       if (annotationType == null) {
         continue;
       }
       TypeSymbol tsym = annotationType.tsym;
-      if (EXEMPTING_METHOD_ANNOTATIONS.contains(tsym.getQualifiedName().toString())) {
+      String annotationName = tsym.getQualifiedName().toString();
+      if (EXEMPTING_METHOD_ANNOTATIONS.contains(annotationName)
+          || exemptMethodAnnotations.contains(annotationName)) {
         return true;
       }
     }

diff --git a/core/src/test/java/com/google/errorprone/bugpatterns/UnusedMethodTest.java b/core/src/test/java/com/google/errorprone/bugpatterns/UnusedMethodTest.java
@@ -14,6 +14,7 @@
 
 package com.google.errorprone.bugpatterns;
 
+import com.google.common.collect.ImmutableList;
 import com.google.errorprone.BugCheckerRefactoringTestHelper;
 import com.google.errorprone.BugCheckerRefactoringTestHelper.TestMode;
 import com.google.errorprone.CompilationTestHelper;
@@ -138,6 +139,21 @@ public void exemptedByName() {
         .doTest();
   }
 
+  @Test
+  public void exemptedByPassingViaArgs() {
+    helper
+        .addSourceLines("Foo.java", "package example;", "@interface Foo {}")
+        .addSourceLines(
+            "ExemptedViaArgs.java",
+            "package example;",
+            "class ExemptedViaArgs {",
+            "  @Foo",
+            "  private void bar() {}",
+            "}")
+        .setArgs(ImmutableList.of("-XepOpt:UnusedMethod:ExemptMethodAnnotations=example.Foo"))
+        .doTest();
+  }
+
   @Test
   public void suppressions() {
     helper