Fix regex used to replace [% %] expressions in text

Was incorrectly truncating at first ']' character

Fixes #21366

Author: nyalldawson

src/core/expression/qgsexpression.cpp

@@ -474,18 +474,19 @@ QString QgsExpression::replaceExpressionText( const QString &action, const QgsEx
   int index = 0;
   while ( index < action.size() )
   {
-    QRegExp rx = QRegExp( "\\[%([^\\]]+)%\\]" );
+    static const QRegularExpression sRegEx{ QStringLiteral( "\\[%(.*?)%\\]" ) };
 
-    int pos = rx.indexIn( action, index );
-    if ( pos < 0 )
+    const QRegularExpressionMatch match = sRegEx.match( action, index );
+    if ( !match.hasMatch() )
       break;
 
-    int start = index;
-    index = pos + rx.matchedLength();
-    QString to_replace = rx.cap( 1 ).trimmed();
-    QgsDebugMsg( "Found expression: " + to_replace );
+    const int pos = action.indexOf( sRegEx, index );
+    const int start = index;
+    index = pos + match.capturedLength( 0 );
+    const QString toReplace = match.captured( 1 ).trimmed();
+    QgsDebugMsg( "Found expression: " + toReplace );
 
-    QgsExpression exp( to_replace );
+    QgsExpression exp( toReplace );
     if ( exp.hasParserError() )
     {
       QgsDebugMsg( "Expression parser error: " + exp.parserErrorString() );

tests/src/core/testqgsexpression.cpp

@@ -3418,6 +3418,26 @@ class TestQgsExpression: public QObject
       QCOMPARE( zustaendigkeitskataster->dataProvider()->featureCount(), 4l );
     }
 
+    void testReplaceExpressionText_data()
+    {
+      QTest::addColumn<QString>( "input" );
+      QTest::addColumn<QString>( "expected" );
+      QTest::newRow( "no exp" ) << "some text" << "some text";
+      QTest::newRow( "simple exp" ) << "some text [% 1 + 2 %]" << "some text 3";
+      QTest::newRow( "multiple exp" ) << "some [% 3+ 7 %] text [% 1 + 2 %]" << "some 10 text 3";
+      QTest::newRow( "complex" ) << "some [%map('a', 1, 'b', 2)['a']%] text [%map('a', 1, 'b', 2)['b']%]" << "some 1 text 2";
+      QTest::newRow( "complex2" ) << "some [% 'my text]' %] text" << "some my text] text";
+    }
+
+    void testReplaceExpressionText()
+    {
+      QFETCH( QString, input );
+      QFETCH( QString, expected );
+
+      QgsExpressionContext context;
+      QCOMPARE( QgsExpression::replaceExpressionText( input, &context ), expected );
+    }
+
 };
 
 QGSTEST_MAIN( TestQgsExpression )