From f666b0008518832c6fd09bf648ed883092cb1293 Mon Sep 17 00:00:00 2001
From: Sylwester Lachiewicz <slachiewicz@apache.org>
Date: Wed, 7 Oct 2026 22:35:26 +0200
Subject: [PATCH] Restore MDEP-835 coverage in the tree IT and drop the unused
 HEAD handler

maven-core 3.9.x no longer depends on commons-lang3, so the tree IT lost
the transitive copy that the optional direct one has to win over. A mock
dependency served by mrm brings it back without adding a real coordinate
for Dependabot to track.
---
 .../repository/tree-optional-consumer-1.0.pom | 38 +++++++++++++++++++
 src/it/projects/tree/expected-v4.txt          |  3 +-
 src/it/projects/tree/expected.txt             |  3 +-
 src/it/projects/tree/pom.xml                  |  6 +++
 .../maven/plugins/dependency/TestGetMojo.java |  3 --
 5 files changed, 48 insertions(+), 5 deletions(-)
 create mode 100644 src/it/mrm/repository/tree-optional-consumer-1.0.pom

diff --git a/src/it/mrm/repository/tree-optional-consumer-1.0.pom b/src/it/mrm/repository/tree-optional-consumer-1.0.pom
new file mode 100644
index 000000000..a84badce1
--- /dev/null
+++ b/src/it/mrm/repository/tree-optional-consumer-1.0.pom
@@ -0,0 +1,38 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+Licensed to the Apache Software Foundation (ASF) under one
+or more contributor license agreements.  See the NOTICE file
+distributed with this work for additional information
+regarding copyright ownership.  The ASF licenses this file
+to you under the Apache License, Version 2.0 (the
+"License"); you may not use this file except in compliance
+with the License.  You may obtain a copy of the License at
+
+  http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing,
+software distributed under the License is distributed on an
+"AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+KIND, either express or implied.  See the License for the
+specific language governing permissions and limitations
+under the License.
+-->
+
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+
+  <!-- brings commons-lang3 into the tree IT transitively with compile scope, so the direct optional declaration there has a transitive one to win over (MDEP-835) -->
+  <groupId>org.apache.maven.its.dependency</groupId>
+  <artifactId>tree-optional-consumer</artifactId>
+  <version>1.0</version>
+
+  <dependencies>
+    <dependency>
+      <groupId>org.apache.commons</groupId>
+      <artifactId>commons-lang3</artifactId>
+      <version>3.18.0</version>
+    </dependency>
+  </dependencies>
+</project>
diff --git a/src/it/projects/tree/expected-v4.txt b/src/it/projects/tree/expected-v4.txt
index bb079c2e8..0738ede5e 100644
--- a/src/it/projects/tree/expected-v4.txt
+++ b/src/it/projects/tree/expected-v4.txt
@@ -31,4 +31,5 @@ org.apache.maven.its.dependency:test:jar:1.0-SNAPSHOT
 |  +- org.codehaus.plexus:plexus-interpolation:jar:1.29:compile
 |  +- org.codehaus.plexus:plexus-component-annotations:jar:2.2.0:compile
 |  \- org.slf4j:slf4j-api:jar:1.7.36:compile
-\- org.apache.commons:commons-lang3:jar:3.18.0:compile (optional)
++- org.apache.commons:commons-lang3:jar:3.18.0:compile (optional)
+\- org.apache.maven.its.dependency:tree-optional-consumer:jar:1.0:compile
diff --git a/src/it/projects/tree/expected.txt b/src/it/projects/tree/expected.txt
index bb079c2e8..0738ede5e 100644
--- a/src/it/projects/tree/expected.txt
+++ b/src/it/projects/tree/expected.txt
@@ -31,4 +31,5 @@ org.apache.maven.its.dependency:test:jar:1.0-SNAPSHOT
 |  +- org.codehaus.plexus:plexus-interpolation:jar:1.29:compile
 |  +- org.codehaus.plexus:plexus-component-annotations:jar:2.2.0:compile
 |  \- org.slf4j:slf4j-api:jar:1.7.36:compile
-\- org.apache.commons:commons-lang3:jar:3.18.0:compile (optional)
++- org.apache.commons:commons-lang3:jar:3.18.0:compile (optional)
+\- org.apache.maven.its.dependency:tree-optional-consumer:jar:1.0:compile
diff --git a/src/it/projects/tree/pom.xml b/src/it/projects/tree/pom.xml
index 5b9102dfe..646acd89c 100644
--- a/src/it/projects/tree/pom.xml
+++ b/src/it/projects/tree/pom.xml
@@ -48,6 +48,12 @@
       <version>3.18.0</version>
       <optional>true</optional>
     </dependency>
+    <!-- mock from src/it/mrm: depends on commons-lang3 with compile scope, which the optional direct one above must beat -->
+    <dependency>
+      <groupId>org.apache.maven.its.dependency</groupId>
+      <artifactId>tree-optional-consumer</artifactId>
+      <version>1.0</version>
+    </dependency>
   </dependencies>
 
 </project>
diff --git a/src/test/java/org/apache/maven/plugins/dependency/TestGetMojo.java b/src/test/java/org/apache/maven/plugins/dependency/TestGetMojo.java
index 95dea2e58..ba32d3656 100644
--- a/src/test/java/org/apache/maven/plugins/dependency/TestGetMojo.java
+++ b/src/test/java/org/apache/maven/plugins/dependency/TestGetMojo.java
@@ -381,9 +381,6 @@ private static void serve(HttpExchange exchange, Path root) throws IOException {
             String method = exchange.getRequestMethod();
             if (!file.startsWith(root) || !Files.isRegularFile(file)) {
                 exchange.sendResponseHeaders(404, -1);
-            } else if ("HEAD".equals(method)) {
-                exchange.getResponseHeaders().set("Content-Length", Long.toString(Files.size(file)));
-                exchange.sendResponseHeaders(200, -1);
             } else if ("GET".equals(method)) {
                 exchange.sendResponseHeaders(200, Files.size(file));
                 try (OutputStream body = exchange.getResponseBody()) {