Merge 2.2 into master

Change-Id: Id7e1b77e70eb04ff84699d2f32ec80f55c8b7ec0

4 files changed, 31 insertions, 13 deletions

diff --git a/src/lib/corelib/language/item.cpp b/src/lib/corelib/language/item.cpp
index 16d570499..29fa1417d 100644
--- a/src/lib/corelib/language/item.cpp
+++ b/src/lib/corelib/language/item.cpp
@@ -284,6 +284,11 @@ bool Item::isPresentModule() const
     return v && v->type() == Value::JSSourceValueType;
 }
 
+bool Item::isFallbackModule() const
+{
+    return hasProperty(QLatin1String("__fallback"));
+}
+
 void Item::setupForBuiltinType(DeprecationWarningMode deprecationMode, Logger &logger)
 {
     assertModuleLocked();
diff --git a/src/lib/corelib/language/item.h b/src/lib/corelib/language/item.h
index 9ee826d6d..d0dde98c4 100644
--- a/src/lib/corelib/language/item.h
+++ b/src/lib/corelib/language/item.h
@@ -182,6 +182,7 @@ public:
     static void removeChild(Item *parent, Item *child);
     void dump() const;
     bool isPresentModule() const;
+    bool isFallbackModule() const;
     void setupForBuiltinType(DeprecationWarningMode deprecationMode, Logger &logger);
     void copyProperty(const QString &propertyName, Item *target) const;
     void overrideProperties(
diff --git a/src/lib/corelib/loader/dependenciesresolver.cpp b/src/lib/corelib/loader/dependenciesresolver.cpp
index 514105e2c..e49af1600 100644
--- a/src/lib/corelib/loader/dependenciesresolver.cpp
+++ b/src/lib/corelib/loader/dependenciesresolver.cpp
@@ -360,13 +360,6 @@ HandleDependency DependenciesResolver::handleResolvedDependencies()
             if (dependency.name.toString() == StringConstants::qbsModule())
                 throw e;
 
-            // This can happen when a property is set unconditionally on a non-required,
-            // non-present dependency. We allow this for user convenience.
-            if (!dependency.requiredLocally) {
-                state.pendingResolvedDependencies.pop();
-                continue;
-            }
-
             // See QBS-1338 for why we do not abort handling the product.
             state.pendingResolvedDependencies.pop();
             Item::Modules &modules = m_product.item->modules();
@@ -1001,21 +994,30 @@ void DependenciesResolver::checkForModuleNamePrefixCollision(
         return;
 
     for (const Item::Module &m : m_product.item->modules()) {
-        if (m.name.length() == dependency.name.length()
-            || m.name.front() != dependency.name.front()) {
+        if (m.name.length() == dependency.name.length())
             continue;
-        }
+
         QualifiedId shortName;
         QualifiedId longName;
-        if (m.name < dependency.name) {
+        if (m.name.length() < dependency.name.length()) {
             shortName = m.name;
             longName = dependency.name;
         } else {
             shortName = dependency.name;
             longName = m.name;
         }
-        throw ErrorInfo(Tr::tr("The name of module '%1' is equal to the first component of the "
-                               "name of module '%2', which is not allowed")
+        const auto isPrefix = [&] {
+            for (int i = 0; i < shortName.length(); ++i) {
+                if (shortName.at(i) != longName.at(i))
+                    return false;
+            }
+            return true;
+        };
+        if (!isPrefix())
+            continue;
+
+        throw ErrorInfo(Tr::tr("The name of module '%1' is a prefix of the name of module '%2', "
+                               "which is not allowed")
                             .arg(shortName.toString(), longName.toString()), dependency.location());
     }
 }
diff --git a/src/lib/corelib/loader/moduleinstantiator.cpp b/src/lib/corelib/loader/moduleinstantiator.cpp
index ab67bc270..1c0359217 100644
--- a/src/lib/corelib/loader/moduleinstantiator.cpp
+++ b/src/lib/corelib/loader/moduleinstantiator.cpp
@@ -135,6 +135,16 @@ void ModuleInstantiator::exchangePlaceholderItem(Item *loadingItem, Item *module
         return;
     }
 
+    if (!moduleItemForItemValues->isPresentModule())
+        return;
+
+    // This will yield false negatives for the case where there is an invalid property attached
+    // for a module that is actually found by pkg-config via the fallback provider.
+    // However, this is extremely rare compared to the case where the presence of the fallback
+    // module simply indicates "not present".
+    if (moduleItemForItemValues->isFallbackModule())
+        return;
+
     // If the old and the new items are the same, it means the existing item value already
     // pointed to a module instance (rather than a placeholder).
     // This can happen in two cases: