Also report ScopedFunctions as static when approporiate

qgis · May 1, 2017 · 7a4527d · 7a4527d
1 parent d70bb9c
commit 7a4527d
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Showing 5 changed files with 37 additions and 3 deletions.
diff --git a/python/core/qgsexpression.sip b/python/core/qgsexpression.sip
@@ -667,6 +667,22 @@ The help text for the function.
  :rtype: bool
 %End
 
+      protected:
+
+        static bool allParamsStatic( const NodeFunction *node, QgsExpression *parent, const QgsExpressionContext *context );
+%Docstring
+ This will return true if all the params for the provided function ``node`` are static within the
+ constraints imposed by the ``context`` within the given ``parent``.
+
+ This can be used as callback for custom implementations of subclasses. It is the default for implementation
+ for StaticFunction.isStatic.
+
+.. note::
+
+   Added in QGIS 3.0
+ :rtype: bool
+%End
+
     };
 
 

diff --git a/src/core/qgsexpression.cpp b/src/core/qgsexpression.cpp
@@ -6552,7 +6552,7 @@ void QgsExpression::StaticFunction::setPrepareFunction( std::function<bool ( con
   mPrepareFunc = prepareFunc;
 }
 
-bool QgsExpression::StaticFunction::allParamsStatic( const QgsExpression::NodeFunction *node, QgsExpression *parent, const QgsExpressionContext *context )
+bool QgsExpression::Function::allParamsStatic( const QgsExpression::NodeFunction *node, QgsExpression *parent, const QgsExpressionContext *context )
 {
   if ( node && node->args() )
   {

diff --git a/src/core/qgsexpression.h b/src/core/qgsexpression.h
@@ -650,6 +650,19 @@ class CORE_EXPORT QgsExpression
 
         virtual bool handlesNull() const { return mHandlesNull; }
 
+      protected:
+
+        /**
+         * This will return true if all the params for the provided function \a node are static within the
+         * constraints imposed by the \a context within the given \a parent.
+         *
+         * This can be used as callback for custom implementations of subclasses. It is the default for implementation
+         * for StaticFunction::isStatic.
+         *
+         * \note Added in QGIS 3.0
+         */
+        static bool allParamsStatic( const NodeFunction *node, QgsExpression *parent, const QgsExpressionContext *context );
+
       private:
         QString mName;
         int mParams;
@@ -800,8 +813,6 @@ class CORE_EXPORT QgsExpression
 
 
       private:
-        static bool allParamsStatic( const NodeFunction *node, QgsExpression *parent, const QgsExpressionContext *context );
-
         FcnEval mFnc;
         QStringList mAliases;
         bool mUsesGeometry;

diff --git a/src/core/qgsexpressioncontext.cpp b/src/core/qgsexpressioncontext.cpp
@@ -1086,3 +1086,8 @@ QSet<QString> QgsScopedExpressionFunction::referencedColumns( const QgsExpressio
   Q_UNUSED( node )
   return mReferencedColumns;
 }
+
+bool QgsScopedExpressionFunction::isStatic( const QgsExpression::NodeFunction *node, QgsExpression *parent, const QgsExpressionContext *context ) const
+{
+  return allParamsStatic( node, parent, context );
+}
diff --git a/src/core/qgsexpressioncontext.h b/src/core/qgsexpressioncontext.h
@@ -93,6 +93,8 @@ class CORE_EXPORT QgsScopedExpressionFunction : public QgsExpression::Function
 
     virtual QSet<QString> referencedColumns( const QgsExpression::NodeFunction *node ) const override;
 
+    virtual bool isStatic( const QgsExpression::NodeFunction *node, QgsExpression *parent, const QgsExpressionContext *context ) const override;
+
   private:
     bool mUsesGeometry;
     QSet<QString> mReferencedColumns;