From c78d871b76c3a9908dad7f9b294a8134111308c8 Mon Sep 17 00:00:00 2001
From: AryanRG <aryanrganjoo@gmail.com>
Date: Sun, 18 Oct 2026 02:46:27 +0530
Subject: [PATCH 1/2] CODEC-347 Handle names emptied during MRA cleaning

Return false from isEncodeEquals when cleaning removes all characters, add public-API regression coverage, and record the issue in the changes log.
---
 src/changes/changes.xml                               |  1 +
 .../codec/language/MatchRatingApproachEncoder.java    |  5 +++++
 .../language/MatchRatingApproachEncoderTest.java      | 11 +++++++++++
 3 files changed, 17 insertions(+)

diff --git a/src/changes/changes.xml b/src/changes/changes.xml
index 1c217375a8..af2df1526a 100644
--- a/src/changes/changes.xml
+++ b/src/changes/changes.xml
@@ -45,6 +45,7 @@ The <action> type attribute can be add,update,fix,remove.
   <body>
     <release version="1.23.1" date="YYYY-MM-DD" description="This is a feature and maintenance release. Java 8 or later is required.">
       <!-- FIX -->
+      <action type="fix" issue="CODEC-347" due-to="Aryan Ganjoo">Avoid a StringIndexOutOfBoundsException when comparing non-identical names that become empty after cleaning in MatchRatingApproachEncoder.isEncodeEquals(String, String).</action>
       <!-- ADD -->
       <!-- UPDATE -->
       <action type="update" dev="ggregory" due-to="Gary Gregory">Bump org.apache.commons:commons-parent from 105 to 106.</action>
diff --git a/src/main/java/org/apache/commons/codec/language/MatchRatingApproachEncoder.java b/src/main/java/org/apache/commons/codec/language/MatchRatingApproachEncoder.java
index e9d9a9e147..664dacf623 100644
--- a/src/main/java/org/apache/commons/codec/language/MatchRatingApproachEncoder.java
+++ b/src/main/java/org/apache/commons/codec/language/MatchRatingApproachEncoder.java
@@ -236,6 +236,11 @@ public boolean isEncodeEquals(String name1, String name2) {
         name1 = cleanName(name1);
         name2 = cleanName(name2);
 
+        // Bulletproof if a name becomes empty after cleanName(name), consistent with encode(String)
+        if (name1.isEmpty() || name2.isEmpty()) {
+            return false;
+        }
+
         // Actual MRA Algorithm
 
         // 1. Remove vowels
diff --git a/src/test/java/org/apache/commons/codec/language/MatchRatingApproachEncoderTest.java b/src/test/java/org/apache/commons/codec/language/MatchRatingApproachEncoderTest.java
index 6d14d0eb7a..d94bb3c034 100644
--- a/src/test/java/org/apache/commons/codec/language/MatchRatingApproachEncoderTest.java
+++ b/src/test/java/org/apache/commons/codec/language/MatchRatingApproachEncoderTest.java
@@ -381,6 +381,17 @@ final void testIsEncodeEqualsSecondNameJust1Letter_ReturnsFalse() {
         assertFalse(getStringEncoder().isEncodeEquals("test", "t"));
     }
 
+    @Test
+    final void testIsEncodeEquals_CornerCase_NameEmptyAfterCleaning_ReturnsFalse() {
+        // Names that become empty after cleanName(String), consistent with encode(String) returning "".
+        assertFalse(getStringEncoder().isEncodeEquals("--", "Smith"));
+        assertFalse(getStringEncoder().isEncodeEquals("Smith", "--"));
+        assertFalse(getStringEncoder().isEncodeEquals(".,-", "Smith"));
+        assertFalse(getStringEncoder().isEncodeEquals("  ", "Smith"));
+        assertFalse(getStringEncoder().isEncodeEquals("Smith", "  "));
+        assertFalse(getStringEncoder().isEncodeEquals("--", ".,"));
+    }
+
     @Test
     final void testIsVowel_CapitalA_ReturnsTrue() {
         assertTrue(getStringEncoder().isVowel("A"));

From 36f838ef96a9237ac47e5800052ca4465a630b5d Mon Sep 17 00:00:00 2001
From: Gary Gregory <garydgregory@users.noreply.github.com>
Date: Sun, 18 Oct 2026 09:27:24 -0400
Subject: [PATCH 2/2] Remove fix action for CODEC-347 from changes.xml

Removed a fix action related to CODEC-347 from the release notes.
---
 src/changes/changes.xml | 1 -
 1 file changed, 1 deletion(-)

diff --git a/src/changes/changes.xml b/src/changes/changes.xml
index af2df1526a..1c217375a8 100644
--- a/src/changes/changes.xml
+++ b/src/changes/changes.xml
@@ -45,7 +45,6 @@ The <action> type attribute can be add,update,fix,remove.
   <body>
     <release version="1.23.1" date="YYYY-MM-DD" description="This is a feature and maintenance release. Java 8 or later is required.">
       <!-- FIX -->
-      <action type="fix" issue="CODEC-347" due-to="Aryan Ganjoo">Avoid a StringIndexOutOfBoundsException when comparing non-identical names that become empty after cleaning in MatchRatingApproachEncoder.isEncodeEquals(String, String).</action>
       <!-- ADD -->
       <!-- UPDATE -->
       <action type="update" dev="ggregory" due-to="Gary Gregory">Bump org.apache.commons:commons-parent from 105 to 106.</action>