Maven: enable configuring maven.top-level-basedir in quarkus:dev

The `quarkus:dev` goal now reads `maven.top-level-basedir` from its
`systemProperties` configuration (which is potentically copied from
Surefire if `copySurefireVariables` is set) and if set, configures
the root project directory for the `BootstrapMavenContext`.

This effectively means that the `maven.top-level-basedir` configuration
may occur not just in a system property, but also in the POM.

Author: Ladicek

devtools/maven/src/main/java/io/quarkus/maven/DevMojo.java

@@ -100,6 +100,7 @@
 import io.quarkus.bootstrap.resolver.BootstrapAppModelResolver;
 import io.quarkus.bootstrap.resolver.maven.BootstrapMavenContext;
 import io.quarkus.bootstrap.resolver.maven.BootstrapMavenContextConfig;
+import io.quarkus.bootstrap.resolver.maven.BootstrapMavenException;
 import io.quarkus.bootstrap.resolver.maven.MavenArtifactResolver;
 import io.quarkus.bootstrap.util.BootstrapUtils;
 import io.quarkus.bootstrap.workspace.ArtifactSources;
@@ -1408,6 +1409,18 @@ private DevModeCommandLine newLauncher(String actualDebugPort, String bootstrapI
         if (appModel != null) {
             bootstrapProvider.close();
         } else {
+            Path rootProjectDir = null;
+            String topLevelBaseDirStr = systemProperties.get(BootstrapMavenContext.MAVEN_TOP_LEVEL_PROJECT_BASEDIR);
+            if (topLevelBaseDirStr != null) {
+                final Path tmp = Path.of(topLevelBaseDirStr);
+                if (!Files.exists(tmp)) {
+                    throw new BootstrapMavenException("Top-level project base directory " + topLevelBaseDirStr
+                            + " specified with system property " + BootstrapMavenContext.MAVEN_TOP_LEVEL_PROJECT_BASEDIR
+                            + " does not exist");
+                }
+                rootProjectDir = tmp;
+            }
+
             final BootstrapMavenContextConfig<?> mvnConfig = BootstrapMavenContext.config()
                     .setUserSettings(session.getRequest().getUserSettingsFile())
                     .setRemoteRepositories(repos)
@@ -1416,7 +1429,8 @@ private DevModeCommandLine newLauncher(String actualDebugPort, String bootstrapI
                     // it's important to set the base directory instead of the POM
                     // which maybe manipulated by a plugin and stored outside the base directory
                     .setCurrentProject(project.getBasedir().toString())
-                    .setEffectiveModelBuilder(BootstrapMavenContextConfig.getEffectiveModelBuilderProperty(projectProperties));
+                    .setEffectiveModelBuilder(BootstrapMavenContextConfig.getEffectiveModelBuilderProperty(projectProperties))
+                    .setRootProjectDir(rootProjectDir);
 
             // There are a couple of reasons we don't want to use the original Maven session:
             // 1) a reload could be triggered by a change in a pom.xml, in which case the Maven session might not be in sync any more with the effective POM;

independent-projects/bootstrap/maven-resolver/src/main/java/io/quarkus/bootstrap/resolver/maven/BootstrapMavenContext.java

@@ -92,7 +92,7 @@ public class BootstrapMavenContext {
     private static final String MAVEN_DOT_HOME = "maven.home";
     private static final String MAVEN_HOME = "MAVEN_HOME";
     private static final String MAVEN_SETTINGS = "maven.settings";
-    private static final String MAVEN_TOP_LEVEL_PROJECT_BASEDIR = "maven.top-level-basedir";
+    public static final String MAVEN_TOP_LEVEL_PROJECT_BASEDIR = "maven.top-level-basedir";
     private static final String SETTINGS_XML = "settings.xml";
     private static final String SETTINGS_SECURITY = "settings.security";