From 02da10ab7a03dcfb2f7fc06a8435bb059832f090 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Christoph=20L=C3=A4ubrich?= <laeubi@laeubi-soft.de>
Date: Fri, 31 May 2024 10:14:26 +0200
Subject: [PATCH] Use the updated p2 metadata once the project is packed

Currently Tycho always uses the INITIAL dependency metadata to compute
the preliminary target platform. As this metadata can change once the
project is packed (e.g. headers added / removed) this can lead to
problems in plugins that depend on the changed plugin because P2 sees
the updated metadata afterwards and fails.

This now distinguish both cases and used the SEED metadata if the
project was already packed.

Fix https://github.com/eclipse-tycho/tycho/issues/3824
---
 .../org/eclipse/tycho/ReactorProjectIdentities.java  |  6 ++++++
 .../eclipse/tycho/p2resolver/P2GeneratorImpl.java    |  3 +--
 .../tycho/p2resolver/TargetPlatformFactoryImpl.java  | 12 +++++++++---
 .../projects/tycho-ds-dependency/.mvn/maven.config   |  1 +
 4 files changed, 17 insertions(+), 5 deletions(-)
 create mode 100644 tycho-its/projects/tycho-ds-dependency/.mvn/maven.config

diff --git a/tycho-api/src/main/java/org/eclipse/tycho/ReactorProjectIdentities.java b/tycho-api/src/main/java/org/eclipse/tycho/ReactorProjectIdentities.java
index 6dbda78107..6d3df43a89 100644
--- a/tycho-api/src/main/java/org/eclipse/tycho/ReactorProjectIdentities.java
+++ b/tycho-api/src/main/java/org/eclipse/tycho/ReactorProjectIdentities.java
@@ -46,4 +46,10 @@ public final int hashCode() {
         return Objects.hash(getArtifactId(), getGroupId(), getVersion());
     }
 
+    @Override
+    public String toString() {
+        return "ReactorProjectIdentities [GroupId=" + getGroupId() + ", ArtifactId=" + getArtifactId() + ", Version="
+                + getVersion() + ", Basedir=" + getBasedir() + "]";
+    }
+
 }
diff --git a/tycho-core/src/main/java/org/eclipse/tycho/p2resolver/P2GeneratorImpl.java b/tycho-core/src/main/java/org/eclipse/tycho/p2resolver/P2GeneratorImpl.java
index 7ba3c924d0..23e0b706f1 100644
--- a/tycho-core/src/main/java/org/eclipse/tycho/p2resolver/P2GeneratorImpl.java
+++ b/tycho-core/src/main/java/org/eclipse/tycho/p2resolver/P2GeneratorImpl.java
@@ -451,8 +451,7 @@ public Map<String, IP2Artifact> generateMetadata(MavenProject project, boolean g
         PublisherOptions options = new PublisherOptions();
         options.setGenerateDownloadStats(generateDownloadStatsProperty);
         options.setGenerateChecksums(generateChecksums);
-        Map<String, IP2Artifact> generatedMetadata = generateMetadata(artifacts, options, targetDir);
-        return generatedMetadata;
+        return generateMetadata(artifacts, options, targetDir);
     }
 
     @Override
diff --git a/tycho-core/src/main/java/org/eclipse/tycho/p2resolver/TargetPlatformFactoryImpl.java b/tycho-core/src/main/java/org/eclipse/tycho/p2resolver/TargetPlatformFactoryImpl.java
index 8818eb0e24..d8e40ff26e 100644
--- a/tycho-core/src/main/java/org/eclipse/tycho/p2resolver/TargetPlatformFactoryImpl.java
+++ b/tycho-core/src/main/java/org/eclipse/tycho/p2resolver/TargetPlatformFactoryImpl.java
@@ -561,9 +561,15 @@ private Map<IInstallableUnit, ReactorProjectIdentities> getPreliminaryReactorPro
         Map<IInstallableUnit, Set<File>> duplicateReactorUIs = new HashMap<>();
 
         for (ReactorProject project : reactorProjects) {
-            Set<IInstallableUnit> projectIUs = project.getDependencyMetadata(DependencyMetadataType.INITIAL);
-
-            if (projectIUs == null) {
+            File artifact = project.getArtifact();
+            Set<IInstallableUnit> projectIUs;
+            if (artifact != null && artifact.isFile()) {
+                //the project was already build, use the seed units as they include anything maybe updated by p2-metadata mojo
+                projectIUs = project.getDependencyMetadata(DependencyMetadataType.SEED);
+            } else {
+                projectIUs = project.getDependencyMetadata(DependencyMetadataType.INITIAL);
+            }
+            if (projectIUs == null || projectIUs.isEmpty()) {
                 continue;
             }
             for (IInstallableUnit iu : projectIUs) {
diff --git a/tycho-its/projects/tycho-ds-dependency/.mvn/maven.config b/tycho-its/projects/tycho-ds-dependency/.mvn/maven.config
new file mode 100644
index 0000000000..3e8679b48c
--- /dev/null
+++ b/tycho-its/projects/tycho-ds-dependency/.mvn/maven.config
@@ -0,0 +1 @@
+-Dtycho.localArtifacts=ignore