From d9d6b57f2a32d9ff1f0cbf55e9960b4dad26e0c8 Mon Sep 17 00:00:00 2001
From: Andreas Dangel <andreas.dangel@pmd-code.org>
Date: Thu, 24 Oct 2024 12:38:45 +0200
Subject: [PATCH] [java] TooFewBranchesForSwitch: report empty switch

This fixes a false negative
---
 .../main/resources/category/java/performance.xml    |  2 +-
 .../performance/xml/TooFewBranchesForSwitch.xml     | 13 +++++++++++++
 2 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/pmd-java/src/main/resources/category/java/performance.xml b/pmd-java/src/main/resources/category/java/performance.xml
index a8e4c37142..f2e7eef431 100644
--- a/pmd-java/src/main/resources/category/java/performance.xml
+++ b/pmd-java/src/main/resources/category/java/performance.xml
@@ -631,7 +631,7 @@ Note: This rule was named TooFewBranchesForASwitchStatement before PMD 7.7.0.
 //(SwitchStatement | SwitchExpression)
   [ (count(*) - 1) < $minimumNumberCaseForASwitch ]
   (: only consider if no pattern matching is used :)
-  [*/SwitchLabel[@PatternLabel = false()]]
+  [not(*/SwitchLabel[@PatternLabel = true()])]
 ]]>
                 </value>
             </property>
diff --git a/pmd-java/src/test/resources/net/sourceforge/pmd/lang/java/rule/performance/xml/TooFewBranchesForSwitch.xml b/pmd-java/src/test/resources/net/sourceforge/pmd/lang/java/rule/performance/xml/TooFewBranchesForSwitch.xml
index 502c470bc2..239aebbb12 100644
--- a/pmd-java/src/test/resources/net/sourceforge/pmd/lang/java/rule/performance/xml/TooFewBranchesForSwitch.xml
+++ b/pmd-java/src/test/resources/net/sourceforge/pmd/lang/java/rule/performance/xml/TooFewBranchesForSwitch.xml
@@ -4,6 +4,19 @@
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:schemaLocation="http://pmd.sourceforge.net/rule-tests http://pmd.sourceforge.net/rule-tests_1_0_0.xsd">
 
+    <test-code>
+        <description>Switch Statement with no case, not ok</description>
+        <rule-property name="minimumNumberCaseForASwitch">3</rule-property>
+        <expected-problems>1</expected-problems>
+        <code><![CDATA[
+public class DumbSwitch {
+    public void foo(int i) {
+        switch (i) { }
+    }
+}
+        ]]></code>
+    </test-code>
+
     <test-code>
         <description>Switch Statement with only one case, not ok</description>
         <rule-property name="minimumNumberCaseForASwitch">3</rule-property>