Check for multiple occurrences of items in SubProject item.

And potentially elsewhere too, if the Item::child() function is used.

Change-Id: I4a5f53e6b1a0f0f49908ce1b8cd34ffce903c38c
Reviewed-by: Joerg Bornemann <joerg.bornemann@digia.com>

4 files changed, 30 insertions, 6 deletions

diff --git a/src/lib/language/item.cpp b/src/lib/language/item.cpp
index a2f1d0b85..85b4dac1f 100644
--- a/src/lib/language/item.cpp
+++ b/src/lib/language/item.cpp
@@ -30,6 +30,8 @@
 #include "item.h"
 #include "itempool.h"
 #include "filecontext.h"
+#include <logging/translator.h>
+#include <tools/error.h>
 #include <tools/qbsassert.h>
 
 namespace qbs {
@@ -126,13 +128,24 @@ void Item::setPropertyObserver(ItemObserver *observer) const
     m_propertyObserver = observer;
 }
 
-Item *Item::child(const QString &type) const
+Item *Item::child(const QString &type, bool checkForMultiple) const
 {
-    foreach (Item * const child, children()) {
-        if (child->typeName() == type)
-            return child;
+    Item *child = 0;
+    foreach (Item * const currentChild, children()) {
+        if (currentChild->typeName() == type) {
+            if (!checkForMultiple)
+                return currentChild;
+            if (child) {
+                ErrorInfo error(Tr::tr("Multiple instances of item '%1' found where at most one "
+                                       "is allowed.").arg(type));
+                error.append(Tr::tr("First item"), child->location());
+                error.append(Tr::tr("Second item"), currentChild->location());
+                throw error;
+            }
+            child = currentChild;
+        }
     }
-    return 0;
+    return child;
 }
 
 } // namespace Internal
diff --git a/src/lib/language/item.h b/src/lib/language/item.h
index ae057455a..af59c0dbd 100644
--- a/src/lib/language/item.h
+++ b/src/lib/language/item.h
@@ -88,7 +88,7 @@ public:
     Item *parent() const;
     const FileContextPtr file() const;
     QList<Item *> children() const;
-    Item *child(const QString &type) const;
+    Item *child(const QString &type, bool checkForMultiple = true) const;
     const PropertyMap &properties() const;
     const PropertyDeclarationMap &propertyDeclarations() const;
     const Modules &modules() const;
diff --git a/src/lib/language/testdata/erroneous/multiple_properties_in_subproject.qbs b/src/lib/language/testdata/erroneous/multiple_properties_in_subproject.qbs
new file mode 100644
index 000000000..0ecb41b34
--- /dev/null
+++ b/src/lib/language/testdata/erroneous/multiple_properties_in_subproject.qbs
@@ -0,0 +1,8 @@
+import qbs
+
+Project {
+    SubProject {
+        Properties { condition: false }
+        Properties { name: "blubb" }
+    }
+}
diff --git a/src/lib/language/tst_language.cpp b/src/lib/language/tst_language.cpp
index b5fa2aae2..25eb90a6d 100644
--- a/src/lib/language/tst_language.cpp
+++ b/src/lib/language/tst_language.cpp
@@ -283,6 +283,9 @@ void TestLanguage::erroneousFiles_data()
             << "Depends.submodules cannot be used if name contains a dot";
     QTest::newRow("multiple_exports")
             << "Multiple Export items in one product are prohibited.";
+    QTest::newRow("multiple_properties_in_subproject")
+            << "Multiple instances of item 'Properties' found where at most one "
+               "is allowed.";
     QTest::newRow("importloop1")
             << "Loop detected when importing";
     QTest::newRow("nonexistentouter")