Add a location to errors in conditions of Properties items

These can be exceedingly difficult to debug otherwise.

Change-Id: Ie3bc42fbd60e11be105fc23624c77a623dc5f1aa
Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>

3 files changed, 31 insertions, 12 deletions

diff --git a/src/lib/corelib/language/astpropertiesitemhandler.cpp b/src/lib/corelib/language/astpropertiesitemhandler.cpp
index 99768a181..b2520ae39 100644
--- a/src/lib/corelib/language/astpropertiesitemhandler.cpp
+++ b/src/lib/corelib/language/astpropertiesitemhandler.cpp
@@ -77,7 +77,8 @@ void ASTPropertiesItemHandler::setupAlternatives()
 class PropertiesBlockConverter
 {
 public:
-    PropertiesBlockConverter(const QString &condition, const QString &overrideListProperties,
+    PropertiesBlockConverter(const JSSourceValue::AltProperty &condition,
+                             const JSSourceValue::AltProperty &overrideListProperties,
                              Item *propertiesBlockContainer, const Item *propertiesBlock)
         : m_propertiesBlockContainer(propertiesBlockContainer)
         , m_propertiesBlock(propertiesBlock)
@@ -144,7 +145,7 @@ private:
     }
 };
 
-static QString getPropertyString(const Item *propertiesItem, const QString &name)
+static JSSourceValue::AltProperty getPropertyData(const Item *propertiesItem, const QString &name)
 {
     const ValuePtr value = propertiesItem->property(name);
     if (!value) {
@@ -152,7 +153,8 @@ static QString getPropertyString(const Item *propertiesItem, const QString &name
             throw ErrorInfo(Tr::tr("Properties.condition must be provided."),
                             propertiesItem->location());
         }
-        return StringConstants::falseValue();
+        return JSSourceValue::AltProperty(StringConstants::falseValue(),
+                                          propertiesItem->location());
     }
     if (Q_UNLIKELY(value->type() != Value::JSSourceValueType)) {
         throw ErrorInfo(Tr::tr("Properties.%1 must be a value binding.").arg(name),
@@ -172,14 +174,13 @@ static QString getPropertyString(const Item *propertiesItem, const QString &name
 
     }
     const JSSourceValuePtr srcval = std::static_pointer_cast<JSSourceValue>(value);
-    return srcval->sourceCodeForEvaluation();
+    return JSSourceValue::AltProperty(srcval->sourceCodeForEvaluation(), srcval->location());
 }
 
 void ASTPropertiesItemHandler::handlePropertiesBlock(const Item *propertiesItem)
 {
-    const QString condition = getPropertyString(propertiesItem,
-                                                StringConstants::conditionProperty());
-    const QString overrideListProperties = getPropertyString(propertiesItem,
+    const auto condition = getPropertyData(propertiesItem, StringConstants::conditionProperty());
+    const auto overrideListProperties = getPropertyData(propertiesItem,
             StringConstants::overrideListPropertiesProperty());
     PropertiesBlockConverter(condition, overrideListProperties, m_parentItem,
                              propertiesItem).apply();
diff --git a/src/lib/corelib/language/evaluatorscriptclass.cpp b/src/lib/corelib/language/evaluatorscriptclass.cpp
index 0a3f4d4c5..5a0eec865 100644
--- a/src/lib/corelib/language/evaluatorscriptclass.cpp
+++ b/src/lib/corelib/language/evaluatorscriptclass.cpp
@@ -252,6 +252,12 @@ private:
         bool hasError = false;
     };
 
+    void injectErrorLocation(QScriptValue &sv, const CodeLocation &loc)
+    {
+        if (sv.isError() && !engine->lastErrorLocation(sv).isValid())
+            sv = engine->currentContext()->throwError(engine->lastError(sv, loc).toString());
+    }
+
     JSSourceValueEvaluationResult evaluateJSSourceValue(const JSSourceValue *value, Item *outerItem,
             const JSSourceValue::Alternative *alternative = nullptr,
             JSSourceValue *elseCaseValue = nullptr, QScriptValue *outerScriptValue = nullptr)
@@ -283,10 +289,11 @@ private:
         pushScope(maybeExtraScope.first);
         pushScope(fileCtxScopes.importScope);
         if (alternative) {
-            QScriptValue sv = engine->evaluate(alternative->condition);
+            QScriptValue sv = engine->evaluate(alternative->condition.value);
             if (engine->hasErrorOrException(sv)) {
                 result.scriptValue = sv;
                 result.hasError = true;
+                injectErrorLocation(result.scriptValue, alternative->condition.location);
                 return result;
             }
             if (sv.toBool()) {
@@ -297,10 +304,12 @@ private:
                 result.tryNextAlternative = true;
                 return result;
             }
-            sv = engine->evaluate(alternative->overrideListProperties);
+            sv = engine->evaluate(alternative->overrideListProperties.value);
             if (engine->hasErrorOrException(sv)) {
                 result.scriptValue = sv;
                 result.hasError = true;
+                injectErrorLocation(result.scriptValue,
+                                    alternative->overrideListProperties.location);
                 return result;
             }
             if (sv.toBool())
diff --git a/src/lib/corelib/language/value.h b/src/lib/corelib/language/value.h
index a1a5be967..6e7eca2f8 100644
--- a/src/lib/corelib/language/value.h
+++ b/src/lib/corelib/language/value.h
@@ -148,8 +148,16 @@ public:
 
     struct Alternative
     {
+        struct PropertyData
+        {
+            PropertyData() = default;
+            PropertyData(const QString &v, const CodeLocation &l) : value(v), location(l) {}
+            QString value;
+            CodeLocation location;
+        };
+
         Alternative() { }
-        Alternative(const QString &c, const QString &o, const JSSourceValuePtr &v)
+        Alternative(const PropertyData &c, const PropertyData &o, const JSSourceValuePtr &v)
             : condition(c), overrideListProperties(o), value(v) {}
         Alternative clone() const
         {
@@ -157,10 +165,11 @@ public:
                                std::static_pointer_cast<JSSourceValue>(value->clone()));
         }
 
-        QString condition;
-        QString overrideListProperties;
+        PropertyData condition;
+        PropertyData overrideListProperties;
         JSSourceValuePtr value;
     };
+    using AltProperty = Alternative::PropertyData;
 
     const std::vector<Alternative> &alternatives() const { return m_alternatives; }
     void addAlternative(const Alternative &alternative) { m_alternatives.push_back(alternative); }