From d86ae16e5e4021fe7bc71c243d3d5c0c0105693a Mon Sep 17 00:00:00 2001
From: "Klare, Heiko" <Heiko.Klare@vector.com>
Date: Fri, 12 Dec 2025 10:02:02 +0100
Subject: [PATCH] Allow to set system property in session tests

The setup used in JUnit 3 ConfigurationSessionTestSuites allows to
set/change system properties for executed sessions. This capability is
currently missing in the JUnit 5 SessionTestExection and the respective
CustomSessionConfiguration. This change adds it.
---
 .../harness/session/CustomSessionConfiguration.java  | 11 +++++++++++
 .../CustomSessionConfigurationDummy.java             |  5 +++++
 .../CustomSessionConfigurationImpl.java              | 12 ++++++++++++
 3 files changed, 28 insertions(+)

diff --git a/runtime/tests/org.eclipse.core.tests.harness/src/org/eclipse/core/tests/harness/session/CustomSessionConfiguration.java b/runtime/tests/org.eclipse.core.tests.harness/src/org/eclipse/core/tests/harness/session/CustomSessionConfiguration.java
index 3a918accf50..544116153ab 100644
--- a/runtime/tests/org.eclipse.core.tests.harness/src/org/eclipse/core/tests/harness/session/CustomSessionConfiguration.java
+++ b/runtime/tests/org.eclipse.core.tests.harness/src/org/eclipse/core/tests/harness/session/CustomSessionConfiguration.java
@@ -83,4 +83,15 @@ public interface CustomSessionConfiguration extends SessionCustomization {
 	 */
 	public CustomSessionConfiguration setConfigIniValue(String key, String value);
 
+	/**
+	 * Sets the given system property for all subsequently executed sessions. If the
+	 * value is null, the property will not be set in subsequent runs anymore.
+	 *
+	 * @param key   the system property key
+	 * @param value the value to set for the key or {@code null} to remove the key
+	 *
+	 * @return this
+	 */
+	public CustomSessionConfiguration setSystemProperty(String key, String value);
+
 }
diff --git a/runtime/tests/org.eclipse.core.tests.harness/src/org/eclipse/core/tests/harness/session/customization/CustomSessionConfigurationDummy.java b/runtime/tests/org.eclipse.core.tests.harness/src/org/eclipse/core/tests/harness/session/customization/CustomSessionConfigurationDummy.java
index 095d42421f6..6cf258aa0fd 100644
--- a/runtime/tests/org.eclipse.core.tests.harness/src/org/eclipse/core/tests/harness/session/customization/CustomSessionConfigurationDummy.java
+++ b/runtime/tests/org.eclipse.core.tests.harness/src/org/eclipse/core/tests/harness/session/customization/CustomSessionConfigurationDummy.java
@@ -68,4 +68,9 @@ public CustomSessionConfiguration setConfigIniValue(String key, String value) {
 		return this;
 	}
 
+	@Override
+	public CustomSessionConfiguration setSystemProperty(String key, String value) {
+		return this;
+	}
+
 }
diff --git a/runtime/tests/org.eclipse.core.tests.harness/src/org/eclipse/core/tests/harness/session/customization/CustomSessionConfigurationImpl.java b/runtime/tests/org.eclipse.core.tests.harness/src/org/eclipse/core/tests/harness/session/customization/CustomSessionConfigurationImpl.java
index 09b56296a1b..d96bcae43c1 100644
--- a/runtime/tests/org.eclipse.core.tests.harness/src/org/eclipse/core/tests/harness/session/customization/CustomSessionConfigurationImpl.java
+++ b/runtime/tests/org.eclipse.core.tests.harness/src/org/eclipse/core/tests/harness/session/customization/CustomSessionConfigurationImpl.java
@@ -53,6 +53,7 @@ public class CustomSessionConfigurationImpl implements CustomSessionConfiguratio
 	private final Collection<BundleReference> bundleReferences = new LinkedHashSet<>();
 	private Path configurationDirectory;
 	private final Map<String, String> configIniValues = new HashMap<>();
+	private final Map<String, String> systemProperties = new HashMap<>();
 	private boolean readOnly = false;
 	private boolean cascaded = false;
 	private boolean firstExecutedSession = true;
@@ -154,6 +155,16 @@ public CustomSessionConfiguration setConfigIniValue(String key, String value) {
 		return this;
 	}
 
+	@Override
+	public CustomSessionConfiguration setSystemProperty(String key, String value) {
+		if (value == null) {
+			systemProperties.remove(key);
+		} else {
+			systemProperties.put(key, value);
+		}
+		return this;
+	}
+
 	@Override
 	public CustomSessionConfiguration setConfigurationDirectory(Path configurationDirectory) {
 		Objects.requireNonNull(configurationDirectory);
@@ -189,6 +200,7 @@ public void prepareSession(Setup setup) throws IOException {
 		if (cascaded) {
 			createOrRefreshConfigIni();
 		}
+		setup.setSystemProperties(systemProperties);
 	}
 
 	@Override