Do not process events in custom scanners' script engines.

Otherwise we will get calls to slots in the executor
at points in time where none are expected.
Note: This means that custom scanner scripts become non-interruptible.
It is not clear if and how we can fix the relevant bug otherwise.
Putting the input artifact scanner into its own thread seems even more
problematic.

Task-number: QBS-782
Change-Id: I44edebfb2a38dc00062cdb9572991ff9352ddd9f
Reviewed-by: Joerg Bornemann <joerg.bornemann@theqtcompany.com>

1 files changed, 10 insertions, 4 deletions

diff --git a/src/lib/corelib/buildgraph/depscanner.cpp b/src/lib/corelib/buildgraph/depscanner.cpp
index 6442d881f..503355db1 100644
--- a/src/lib/corelib/buildgraph/depscanner.cpp
+++ b/src/lib/corelib/buildgraph/depscanner.cpp
@@ -120,17 +120,23 @@ const void *PluginDependencyScanner::key() const
 }
 
 UserDependencyScanner::UserDependencyScanner(const ResolvedScannerConstPtr &scanner,
-        const Logger &logger, ScriptEngine *engine)
+        const Logger &logger)
     : m_scanner(scanner),
       m_logger(logger),
-      m_engine(engine),
-      m_observer(engine),
+      m_engine(new ScriptEngine(logger)),
+      m_observer(m_engine),
       m_product(0)
 {
-    m_global = engine->newObject();
+    m_engine->setProcessEventsInterval(-1); // QBS-782
+    m_global = m_engine->newObject();
     setupScriptEngineForFile(m_engine, m_scanner->scanScript->fileContext, m_global);
 }
 
+UserDependencyScanner::~UserDependencyScanner()
+{
+    delete m_engine;
+}
+
 QStringList UserDependencyScanner::collectSearchPaths(Artifact *artifact)
 {
     return evaluate(artifact, m_scanner->searchPathsScript);