CppEditor: Fix crash with invalid switch/case statement

Task-number: QTCREATORBUG-14925
Change-Id: Iea2cf17070d9db48924e76f6c7febca0d52e4686
Reviewed-by: Marco Bubke <marco.bubke@theqtcompany.com>
Reviewed-by: Orgad Shaneh <orgads@gmail.com>

2 files changed, 22 insertions, 5 deletions

diff --git a/src/plugins/cppeditor/cppquickfix_test.cpp b/src/plugins/cppeditor/cppquickfix_test.cpp
index cbc04f6a67..962afeddd0 100644
--- a/src/plugins/cppeditor/cppquickfix_test.cpp
+++ b/src/plugins/cppeditor/cppquickfix_test.cpp
@@ -514,6 +514,21 @@ void CppEditorPlugin::test_quickfix_data()
         "}\n"
     );
 
+    // Checks: Do not crash on incomplete case statetement.
+    QTest::newRow("CompleteSwitchCaseStatement_doNotCrashOnIncompleteCase")
+        << CppQuickFixFactoryPtr(new CompleteSwitchCaseStatement) << _(
+        "enum E {};\n"
+        "void f(E o)\n"
+        "{\n"
+        "    @switch (o)\n"
+        "    {\n"
+        "    case\n"
+        "    }\n"
+        "}\n"
+        ) << _(
+        ""
+    );
+
     // Checks:
     // 1. If the name does not start with ("m_" or "_") and does not
     //    end with "_", we are forced to prefix the getter with "get".
diff --git a/src/plugins/cppeditor/cppquickfixes.cpp b/src/plugins/cppeditor/cppquickfixes.cpp
index 736638ef92..28d711cf8e 100644
--- a/src/plugins/cppeditor/cppquickfixes.cpp
+++ b/src/plugins/cppeditor/cppquickfixes.cpp
@@ -2212,11 +2212,13 @@ public:
     bool preVisit(AST *ast) {
         if (CaseStatementAST *cs = ast->asCaseStatement()) {
             foundCaseStatementLevel = true;
-            if (ExpressionAST *expression = cs->expression->asIdExpression()) {
-                QList<LookupItem> candidates = typeOfExpression(expression, document, scope);
-                if (!candidates .isEmpty() && candidates.first().declaration()) {
-                    Symbol *decl = candidates.first().declaration();
-                    values << prettyPrint.prettyName(LookupContext::fullyQualifiedName(decl));
+            if (ExpressionAST *csExpression = cs->expression) {
+                if (ExpressionAST *expression = csExpression->asIdExpression()) {
+                    QList<LookupItem> candidates = typeOfExpression(expression, document, scope);
+                    if (!candidates .isEmpty() && candidates.first().declaration()) {
+                        Symbol *decl = candidates.first().declaration();
+                        values << prettyPrint.prettyName(LookupContext::fullyQualifiedName(decl));
+                    }
                 }
             }
             return true;