QTestLib: don't crash if data tag requested, none available

When specific test functions and data tags are requested from the
command line, a non-existing data tag will produce error output *iif*
data tags are available for the function. However, if no data tags are
available, element 0 in testData would be dereferenced, resulting in a
crash.

Special case the empty data tag, even if no tags are available, because
some loggers (e.g., the QXmlTestLogger) will output results with no tag
the same way as those with an empty data tag.

Reviewed-by: Morten Sørvig

1 files changed, 13 insertions, 1 deletions

diff --git a/src/testlib/qtestcase.cpp b/src/testlib/qtestcase.cpp
index ecdcca8312..1c2db2fe0f 100644
--- a/src/testlib/qtestcase.cpp
+++ b/src/testlib/qtestcase.cpp
@@ -1298,11 +1298,23 @@ static bool qInvokeTestMethod(const char *slotName, const char *data=0)
             const int dataCount = table.dataCount();
             QTestResult::setSkipCurrentTest(false);
 
+            // Data tag requested but none available?
+            if (data && !dataCount) {
+                // Let empty data tag through.
+                if (!*data)
+                    data = 0;
+                else {
+                    printf("Unknown testdata for function %s: '%s'\n", slotName, data);
+                    printf("Function has no testdata.\n");
+                    return false;
+                }
+            }
+
             /* For each entry in the data table, do: */
             do {
                 if (!data || !qstrcmp(data, table.testData(curDataIndex)->dataTag())) {
                     foundFunction = true;
-                    QTestDataSetter s(table.isEmpty() ? static_cast<QTestData *>(0)
+                    QTestDataSetter s(curDataIndex >= dataCount ? static_cast<QTestData *>(0)
                                                       : table.testData(curDataIndex));
 
                     qInvokeTestMethodDataEntry(slot);