Handle multiple labels in UnnecessaryDefaultInEnumSwitch

Fixes #4443 PiperOrigin-RevId: 655286660
google · Jul 23, 2024 · a01c164 · a01c164
1 parent 7b58ec9
commit a01c164
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diff --git a/core/src/main/java/com/google/errorprone/bugpatterns/UnnecessaryDefaultInEnumSwitch.java b/core/src/main/java/com/google/errorprone/bugpatterns/UnnecessaryDefaultInEnumSwitch.java
@@ -231,7 +231,7 @@ private static boolean trivialDefault(List<? extends StatementTree> defaultState
   private static SetView<String> unhandledCases(SwitchTree tree, TypeSymbol switchType) {
     ImmutableSet<String> handledCases =
         tree.getCases().stream()
-            .map(CaseTree::getExpression)
+            .flatMap(ASTHelpers::getCaseExpressions)
             .filter(IdentifierTree.class::isInstance)
             .map(p -> ((IdentifierTree) p).getName().toString())
             .collect(toImmutableSet());

diff --git a/core/src/test/java/com/google/errorprone/bugpatterns/UnnecessaryDefaultInEnumSwitchTest.java b/core/src/test/java/com/google/errorprone/bugpatterns/UnnecessaryDefaultInEnumSwitchTest.java
@@ -821,4 +821,30 @@ public void unrecognizedCaseKindRule() {
             "}")
         .doTest();
   }
+
+  @Test
+  public void multipleLabels() {
+    assumeTrue(RuntimeVersion.isAtLeast14());
+    compilationHelper
+        .addSourceLines(
+            "Test.java",
+            "class Test {",
+            "  enum Type {",
+            "    FOO, BAR, BAZ,",
+            "  }",
+            "  public static void main(String[] args) {",
+            "    var type = Type.valueOf(args[0]);",
+            "    switch (type) {",
+            "      case FOO -> {",
+            "        System.out.println(\"Hi foo\");",
+            "      }",
+            "      case BAR, BAZ -> {",
+            "      }",
+            "      // BUG: Diagnostic contains: UnnecessaryDefaultInEnumSwitch",
+            "      default -> throw new AssertionError(type);",
+            "    }",
+            "  }",
+            "}")
+        .doTest();
+  }
 }