Merge branch 'expr'

Author: wonder-sk

python/core/core.sip

@@ -35,6 +35,7 @@
 %Include qgsdataprovider.sip
 %Include qgsdatasourceuri.sip
 %Include qgsdistancearea.sip
+%Include qgsexpression.sip
 %Include qgsfeature.sip
 %Include qgsfield.sip
 %Include qgsgeometry.sip

python/core/qgsexpression.sip

@@ -0,0 +1,64 @@
+
+class QgsExpression
+{
+%TypeHeaderCode
+#include "qgsexpression.h"
+%End
+
+public:
+  QgsExpression( const QString& expr );
+  ~QgsExpression();
+
+  //! Returns true if an error occurred when parsing the input expression
+  bool hasParserError() const;
+  //! Returns parser error
+  QString parserErrorString() const;
+
+  //! Get the expression ready for evaluation - find out column indexes.
+  bool prepare( const QgsFieldMap& fields );
+
+  //! Get list of columns referenced by the expression
+  QStringList referencedColumns();
+  //! Returns true if the expression uses feature geometry for some computation
+  bool needsGeometry();
+
+  // evaluation
+
+  //! Evaluate the feature and return the result
+  //! @note prepare() should be called before calling this method
+  QVariant evaluate( QgsFeature* f = NULL );
+
+  //! Evaluate the feature and return the result
+  //! @note this method does not expect that prepare() has been called on this instance
+  QVariant evaluate( QgsFeature* f, const QgsFieldMap& fields );
+
+  //! Returns true if an error occurred when evaluating last input
+  bool hasEvalError() const;
+  //! Returns evaluation error
+  QString evalErrorString() const;
+  //! Set evaluation error (used internally by evaluation functions)
+  void setEvalErrorString( QString str );
+
+  //! Set the number for $rownum special column
+  void setCurrentRowNumber( int rowNumber );
+  //! Return the number used for $rownum special column
+  int currentRowNumber();
+
+  //! Return the parsed expression as a string - useful for debugging
+  QString dump() const;
+
+  //! Return calculator used for distance and area calculations
+  //! (used by internal functions)
+  QgsDistanceArea* geomCalculator();
+
+  //
+
+  // tells whether the identifier is a name of existing function
+  static bool isFunctionName( QString name );
+
+  // return index of the function in BuiltinFunctions array
+  static int functionIndex( QString name );
+
+  //! return quoted column reference (in double quotes)
+  static QString quotedColumnRef( QString name );
+};

python/core/symbology-ng-core.sip

@@ -407,14 +407,15 @@ class QgsRuleBasedRendererV2 : QgsFeatureRendererV2
         ~Rule();
         QString dump() const;
         QStringList needsFields() const;
-        bool isFilterOK( const QgsFieldMap& fields, QgsFeature& f ) const;
+        bool isFilterOK( QgsFeature& f ) const;
         bool isScaleOK( double scale ) const;
 
         QgsSymbolV2* symbol();
         bool dependsOnScale() const;
         int scaleMinDenom() const;
         int scaleMaxDenom() const;
         QString filterExpression() const;
+        QgsExpression* filter() const;
 
         void setScaleMinDenom( int scaleMinDenom );
         void setScaleMaxDenom( int scaleMaxDenom );

src/app/attributetable/qgsattributetabledialog.cpp

@@ -24,8 +24,7 @@
 #include <qgsapplication.h>
 #include <qgsvectordataprovider.h>
 #include <qgsvectorlayer.h>
-#include <qgssearchstring.h>
-#include <qgssearchtreenode.h>
+#include <qgsexpression.h>
 
 #include "qgisapp.h"
 #include "qgsaddattrdialog.h"
@@ -532,23 +531,21 @@ void QgsAttributeTableDialog::updateSelectionFromLayer()
 void QgsAttributeTableDialog::doSearch( QString searchString )
 {
   // parse search string and build parsed tree
-  QgsSearchString search;
-  if ( !search.setString( searchString ) )
+  QgsExpression search( searchString );
+  if ( search.hasParserError() )
   {
-    QMessageBox::critical( this, tr( "Search string parsing error" ), search.parserErrorMsg() );
+    QMessageBox::critical( this, tr( "Parsing error" ), search.parserErrorString() );
     return;
   }
 
-  QgsSearchTreeNode* searchTree = search.tree();
-  if ( searchTree == NULL )
+  if ( ! search.prepare( mLayer->pendingFields() ) )
   {
-    QMessageBox::information( this, tr( "Search results" ), tr( "You've supplied an empty search string." ) );
-    return;
+    QMessageBox::critical( this, tr( "Evaluation error" ), search.evalErrorString() );
   }
 
   // TODO: fetch only necessary columns
-  // QStringList columns = searchTree->referencedColumns();
-  bool fetchGeom = searchTree->needsGeometry();
+  //QStringList columns = search.referencedColumns();
+  bool fetchGeom = search.needsGeometry();
 
   QApplication::setOverrideCursor( Qt::WaitCursor );
   mSelectedFeatures.clear();
@@ -558,11 +555,12 @@ void QgsAttributeTableDialog::doSearch( QString searchString )
     QgsFeatureList selectedFeatures = mLayer->selectedFeatures();
     for ( QgsFeatureList::Iterator it = selectedFeatures.begin(); it != selectedFeatures.end(); ++it )
     {
-      if ( searchTree->checkAgainst( mLayer->pendingFields(), *it ) )
-        mSelectedFeatures << it->id();
+      QgsFeature& feat = *it;
+      if ( search.evaluate( &feat ).toInt() != 0 )
+        mSelectedFeatures << feat.id();
 
       // check if there were errors during evaluating
-      if ( searchTree->hasError() )
+      if ( search.hasEvalError() )
         break;
     }
   }
@@ -573,20 +571,20 @@ void QgsAttributeTableDialog::doSearch( QString searchString )
 
     while ( mLayer->nextFeature( f ) )
     {
-      if ( searchTree->checkAgainst( mLayer->pendingFields(), f ) )
+      if ( search.evaluate( &f ).toInt() != 0 )
         mSelectedFeatures << f.id();
 
       // check if there were errors during evaluating
-      if ( searchTree->hasError() )
+      if ( search.hasEvalError() )
         break;
     }
   }
 
   QApplication::restoreOverrideCursor();
 
-  if ( searchTree->hasError() )
+  if ( search.hasEvalError() )
   {
-    QMessageBox::critical( this, tr( "Error during search" ), searchTree->errorMsg() );
+    QMessageBox::critical( this, tr( "Error during search" ), search.evalErrorString() );
     return;
   }
 
@@ -625,12 +623,12 @@ void QgsAttributeTableDialog::search()
   QString str;
   if ( mQuery->displayText() == nullValue )
   {
-    str = QString( "%1 IS NULL" ).arg( QgsSearchTreeNode::quotedColumnRef( fieldName ) );
+    str = QString( "%1 IS NULL" ).arg( QgsExpression::quotedColumnRef( fieldName ) );
   }
   else
   {
     str = QString( "%1 %2 '%3'" )
-          .arg( QgsSearchTreeNode::quotedColumnRef( fieldName ) )
+          .arg( QgsExpression::quotedColumnRef( fieldName ) )
           .arg( numeric ? "=" : sensString )
           .arg( numeric
                 ? mQuery->displayText().replace( "'", "''" )

src/app/qgsattributedialog.cpp

@@ -24,8 +24,7 @@
 #include "qgssymbol.h"
 #include "qgsattributeeditor.h"
 #include "qgshighlight.h"
-#include "qgssearchstring.h"
-#include "qgssearchtreenode.h"
+#include "qgsexpression.h"
 #include "qgspythonrunner.h"
 
 #include "qgisapp.h"
@@ -208,15 +207,12 @@ QgsAttributeDialog::QgsAttributeDialog( QgsVectorLayer *vl, QgsFeature *thepFeat
       QString expr = le->text();
       le->setText( tr( "Error" ) );
 
-      QgsSearchString ss;
-      if ( !ss.setString( expr ) )
+      QgsExpression exp( expr );
+      if ( exp.hasParserError() )
         continue;
 
-      QgsSearchTreeNode *st = ss.tree();
-      if ( !st )
-        continue;
 
-      if ( !mFeature->geometry() && st->needsGeometry() )
+      if ( !mFeature->geometry() && exp.needsGeometry() )
       {
         QgsFeature f;
         if ( vl->featureAtId( mFeature->id(), f, true, false ) && f.geometry() )
@@ -225,19 +221,24 @@ QgsAttributeDialog::QgsAttributeDialog( QgsVectorLayer *vl, QgsFeature *thepFeat
         }
       }
 
-      QgsSearchTreeValue value;
-      st->getValue( value, st, vl->pendingFields(), *mFeature );
+      QVariant value = exp.evaluate( mFeature, vl->pendingFields() );
 
-      if ( !value.isError() )
+      if ( !exp.hasEvalError() )
       {
-        if ( value.isNumeric() )
-          le->setText( QString::number( value.number() ) );
-        else
-          le->setText( value.string() );
+        QString text;
+        switch ( value.type() )
+        {
+          case QVariant::Invalid: text = "NULL"; break;
+          case QVariant::Int: text = QString::number( value.toInt() ); break;
+          case QVariant::Double: text = QString::number( value.toDouble() ); break;
+          case QVariant::String:
+          default: text = value.toString();
+        }
+        le->setText( text );
       }
       else
       {
-        le->setText( tr( "Error: %1" ).arg( st->errorMsg() ) );
+        le->setText( tr( "Error: %1" ).arg( exp.evalErrorString() ) );
       }
     }
   }

src/app/qgsfieldcalculator.cpp

@@ -14,8 +14,7 @@
  ***************************************************************************/
 
 #include "qgsfieldcalculator.h"
-#include "qgssearchtreenode.h"
-#include "qgssearchstring.h"
+#include "qgsexpression.h"
 #include "qgsvectordataprovider.h"
 #include "qgsvectorlayer.h"
 
@@ -81,19 +80,18 @@ void QgsFieldCalculator::accept()
   {
     QString calcString = mExpressionTextEdit->toPlainText();
 
-    //create QgsSearchString
-    QgsSearchString searchString;
-    if ( !searchString.setString( calcString ) )
+    //create QgsExpression
+    QgsExpression exp( calcString );
+    if ( exp.hasParserError() )
     {
       //expression not valid
-      QMessageBox::critical( 0, tr( "Syntax error" ), tr( QString( "Invalid expression syntax. The error message of the parser is: '" + searchString.parserErrorMsg() + "'" ).toLocal8Bit().data() ) );
+      QMessageBox::critical( 0, tr( "Syntax error" ), tr( QString( "Invalid expression syntax. The error message of the parser is: '" + exp.parserErrorString() + "'" ).toLocal8Bit().data() ) );
       return;
     }
 
-    //get QgsSearchTreeNode
-    QgsSearchTreeNode* searchTree = searchString.tree();
-    if ( !searchTree )
+    if ( ! exp.prepare( mVectorLayer->pendingFields() ) )
     {
+      QMessageBox::critical( 0, tr( "Evaluation error" ), exp.evalErrorString() );
       return;
     }
 
@@ -156,7 +154,7 @@ void QgsFieldCalculator::accept()
     // block layerModified signals (that would trigger table update)
     mVectorLayer->blockSignals( true );
 
-    bool useGeometry = searchTree->needsGeometry();
+    bool useGeometry = exp.needsGeometry();
     int rownum = 1;
 
     mVectorLayer->select( mVectorLayer->pendingAllAttributesList(), QgsRectangle(), useGeometry, false );
@@ -170,52 +168,18 @@ void QgsFieldCalculator::accept()
         }
       }
 
-      searchTree->setCurrentRowNumber( rownum );
+      exp.setCurrentRowNumber( rownum );
 
-      QgsSearchTreeValue value;
-      searchTree->getValue( value, searchTree, mVectorLayer->pendingFields(), feature );
-      if ( value.isError() )
+      QVariant value = exp.evaluate( &feature );
+      if ( exp.hasEvalError() )
       {
-        //insert NULL value for this feature and continue the calculation
-        if ( searchTree->errorMsg() == QObject::tr( "Division by zero." ) )
-        {
-          mVectorLayer->changeAttributeValue( feature.id(), mAttributeId, QVariant(), false );
-        }
-        else
-        {
-          calculationSuccess = false;
-          error = searchTree->errorMsg();
-          break;
-        }
-      }
-      else if ( value.isNumeric() )
-      {
-        const QgsField &f = mVectorLayer->pendingFields()[ mAttributeId ];
-        QVariant v;
-
-        if ( f.type() == QVariant::Double && f.precision() > 0 )
-        {
-          v = QString::number( value.number(), 'f', f.precision() );
-        }
-        else if ( f.type() == QVariant::Double && f.precision() == 0 )
-        {
-          v = QString::number( qRound( value.number() ) );
-        }
-        else
-        {
-          v = value.number();
-        }
-
-        v.convert( f.type() );
-        mVectorLayer->changeAttributeValue( feature.id(), mAttributeId, v, false );
-      }
-      else if ( value.isNull() )
-      {
-        mVectorLayer->changeAttributeValue( feature.id(), mAttributeId, QVariant(), false );
+        calculationSuccess = false;
+        error = exp.evalErrorString();
+        break;
       }
       else
       {
-        mVectorLayer->changeAttributeValue( feature.id(), mAttributeId, value.string(), false );
+        mVectorLayer->changeAttributeValue( feature.id(), mAttributeId, value, false );
       }
 
       rownum++;
@@ -385,17 +349,17 @@ void QgsFieldCalculator::on_mCloseBracketPushButton_clicked()
 
 void QgsFieldCalculator::on_mToRealButton_clicked()
 {
-  mExpressionTextEdit->insertPlainText( " to real ( " );
+  mExpressionTextEdit->insertPlainText( " toreal ( " );
 }
 
 void QgsFieldCalculator::on_mToIntButton_clicked()
 {
-  mExpressionTextEdit->insertPlainText( " to int ( " );
+  mExpressionTextEdit->insertPlainText( " toint ( " );
 }
 
 void QgsFieldCalculator::on_mToStringButton_clicked()
 {
-  mExpressionTextEdit->insertPlainText( " to string ( " );
+  mExpressionTextEdit->insertPlainText( " tostring ( " );
 }
 
 void QgsFieldCalculator::on_mLengthButton_clicked()