shiboken6: Refactor resolving of inner container types in argument default values

Add an explanatory comment, rewrite without regexes and add a test.

Task-number: PYSIDE-1691
Change-Id: Idfa5022016d16f29718042b4677f248d20418a22
Reviewed-by: Cristian Maureira-Fredes <cristian.maureira-fredes@qt.io>
(cherry picked from commit 8ab90a73c792bd20deced21bad878c349f758605)

2 files changed, 50 insertions, 8 deletions

diff --git a/sources/shiboken6/ApiExtractor/abstractmetabuilder.cpp b/sources/shiboken6/ApiExtractor/abstractmetabuilder.cpp
index d4847f401..d50d2f5f6 100644
--- a/sources/shiboken6/ApiExtractor/abstractmetabuilder.cpp
+++ b/sources/shiboken6/ApiExtractor/abstractmetabuilder.cpp
@@ -2511,6 +2511,17 @@ qint64 AbstractMetaBuilderPrivate::findOutValueFromString(const QString &stringV
     return 0;
 }
 
+// Return whether candidate is some underqualified specification of qualifiedType
+// ("B::C" should be qualified to "A::B::C")
+static bool isUnderQualifiedSpec(QStringView qualifiedType, QStringView candidate)
+{
+    const auto candidateSize = candidate.size();
+    const auto qualifiedTypeSize = qualifiedType.size();
+    return candidateSize < qualifiedTypeSize
+        && qualifiedType.endsWith(candidate)
+        && qualifiedType.at(qualifiedTypeSize - candidateSize - 1) == u':';
+}
+
 QString AbstractMetaBuilder::fixEnumDefault(const AbstractMetaType &type,
                                             const QString &expr) const
 {
@@ -2544,14 +2555,25 @@ QString AbstractMetaBuilderPrivate::fixDefaultValue(QString expr, const Abstract
     } else if (type.isFlags() || type.isEnum()) {
         expr = fixEnumDefault(type, expr);
     } else if (type.isContainer() && expr.contains(QLatin1Char('<'))) {
-        static const QRegularExpression typeRegEx(QStringLiteral("[^<]*<(.*)>"));
-        Q_ASSERT(typeRegEx.isValid());
-        const QRegularExpressionMatch typeMatch = typeRegEx.match(type.minimalSignature());
-        static const QRegularExpression defaultRegEx(QLatin1String("([^<]*<).*(>[^>]*)"));
-        Q_ASSERT(defaultRegEx.isValid());
-        const QRegularExpressionMatch defaultMatch = defaultRegEx.match(expr);
-        if (typeMatch.hasMatch() && defaultMatch.hasMatch())
-            expr = defaultMatch.captured(1) + typeMatch.captured(1) + defaultMatch.captured(2);
+        // Expand a container of a nested class, fex
+        // "QList<FormatRange>()" -> "QList<QTextLayout::FormatRange>()"
+        if (type.instantiations().size() != 1)
+            return expr; // Only simple types are handled, not QMap<int, int>.
+        auto *innerTypeEntry = type.instantiations().constFirst().typeEntry();
+        if (!innerTypeEntry->isComplex())
+            return expr;
+        const QString &qualifiedInnerTypeName = innerTypeEntry->qualifiedCppName();
+        if (!qualifiedInnerTypeName.contains(u"::")) // Nothing to qualify here
+            return expr;
+        const auto openPos = expr.indexOf(u'<');
+        const auto closingPos = expr.lastIndexOf(u'>');
+        if (openPos == -1 || closingPos == -1)
+            return expr;
+        const auto innerPos = openPos + 1;
+        const auto innerLen = closingPos - innerPos;
+        const auto innerType = QStringView{expr}.mid(innerPos, innerLen).trimmed();
+        if (isUnderQualifiedSpec(qualifiedInnerTypeName, innerType))
+            expr.replace(innerPos, innerLen, qualifiedInnerTypeName);
     } else {
         // Here the default value is supposed to be a constructor,
         // a class field, or a constructor receiving a class field
diff --git a/sources/shiboken6/ApiExtractor/tests/testresolvetype.cpp b/sources/shiboken6/ApiExtractor/tests/testresolvetype.cpp
index c88dd7a53..809e3b824 100644
--- a/sources/shiboken6/ApiExtractor/tests/testresolvetype.cpp
+++ b/sources/shiboken6/ApiExtractor/tests/testresolvetype.cpp
@@ -76,6 +76,7 @@ struct DefaultValuesFixture
     AbstractMetaType intType;
     AbstractMetaType stringType;
     AbstractMetaType classType;
+    AbstractMetaType listType;
     const AbstractMetaClass *klass{};
 };
 
@@ -86,6 +87,8 @@ static int populateDefaultValuesFixture(DefaultValuesFixture *fixture)
 {
     static const char cppCode[] =R"(
 #include <string>
+#include <list>
+
 namespace Namespace {
 class Test
 {
@@ -93,6 +96,8 @@ public:
     explicit Test(int x = INT_FIELD_1);
     explicit Test(const std::string &t = std::string(CHAR_FIELD_1));
 
+    static void listFunc(std::list<Test> list = std::list<Test>());
+
     static const int INT_FIELD_1 = 42;
     static const char *CHAR_FIELD_1;
 };
@@ -106,6 +111,7 @@ public:
     <namespace-type name='Namespace'>
         <value-type name='Test'/>
     </namespace-type>
+    <container-type name="std::list" type="list"/>
 </typesystem>
 )";
 
@@ -138,6 +144,11 @@ public:
     if (fixture->intType.isVoid() || fixture->stringType.isVoid())
         return -3;
 
+    auto listFunc = fixture->klass->findFunction(u"listFunc"_qs);
+    if (listFunc.isNull() || listFunc->arguments().size() != 1)
+        return -3;
+    fixture->listType = listFunc->arguments().constFirst().type();
+
     return 0;
 }
 
@@ -154,6 +165,15 @@ void TestResolveType::testFixDefaultArguments_data()
 
     QTest::newRow("int") << fixture << setupOk
         << fixture.intType << "1" << "1";
+
+    // Test expansion of container types
+    QString expected = u"std::list<Namespace::Test>()"_qs;
+    QTest::newRow("list")
+        << fixture << setupOk << fixture.listType
+        << expected << expected;
+    QTest::newRow("partially qualified list")
+        << fixture << setupOk << fixture.listType
+        << "std::list<Test>()" << expected;
 }
 
 void TestResolveType::testFixDefaultArguments()