shiboken6: Fix crash when parsing adding functions with empty parameter type

Writing something like <add-function signature="foo(,,a)"/>
would cause a crash. Bail out with an error instead.

Pick-to: 6.1
Change-Id: I9e49cdbcd44b53e603afdcc863fa8b93a750250d
Reviewed-by: Christian Tismer <tismer@stackless.com>

2 files changed, 8 insertions, 2 deletions

diff --git a/sources/shiboken6/ApiExtractor/modifications.cpp b/sources/shiboken6/ApiExtractor/modifications.cpp
index f5afef124..118b511e6 100644
--- a/sources/shiboken6/ApiExtractor/modifications.cpp
+++ b/sources/shiboken6/ApiExtractor/modifications.cpp
@@ -357,8 +357,11 @@ AddedFunction::AddedFunctionPtr
     for (const auto &p : params) {
         TypeInfo type = p.type == QLatin1String("...")
             ? TypeInfo::varArgsType() : TypeParser::parse(p.type, errorMessage);
-        if (!errorMessage->isEmpty())
+        if (!errorMessage->isEmpty()) {
+            errorMessage->prepend(u"Unable to parse added function "_qs + signatureIn
+                                  + u": "_qs);
             return {};
+        }
         arguments.append({type, p.name, p.defaultValue});
     }
 
diff --git a/sources/shiboken6/ApiExtractor/typeparser.cpp b/sources/shiboken6/ApiExtractor/typeparser.cpp
index 38c556d41..fba3a8801 100644
--- a/sources/shiboken6/ApiExtractor/typeparser.cpp
+++ b/sources/shiboken6/ApiExtractor/typeparser.cpp
@@ -307,6 +307,9 @@ TypeInfo TypeParser::parse(const QString &str, QString *errorMessage)
         tok = scanner.nextToken();
     }
 
-    Q_ASSERT(!stack.isEmpty());
+    if (stack.isEmpty() || stack.constFirst().qualifiedName().isEmpty()) {
+        *errorMessage = u"Unable to parse type \""_qs + str + u"\"."_qs;
+        return {};
+    }
     return stack.constFirst();
 }