Optimise comparison of date/time/datetime values in expressions

nyalldawson · nyalldawson · commit 61f1566285a3 · 2020-05-09T05:18:06.000+10:00
Avoid forced conversion to string when comparing the same date/time
types
diff --git a/src/core/expression/qgsexpressionnodeimpl.cpp b/src/core/expression/qgsexpressionnodeimpl.cpp
@@ -403,6 +403,30 @@ QVariant QgsExpressionNodeBinaryOperator::evalNode( QgsExpression *parent, const
             return TVL_Unknown;
         }
       }
+      else if ( ( vL.type() == QVariant::DateTime && vR.type() == QVariant::DateTime ) )
+      {
+        const QDateTime dL = QgsExpressionUtils::getDateTimeValue( vL, parent );
+        ENSURE_NO_EVAL_ERROR;
+        const QDateTime dR = QgsExpressionUtils::getDateTimeValue( vR, parent );
+        ENSURE_NO_EVAL_ERROR;
+        return compare( dR.msecsTo( dL ) ) ? TVL_True : TVL_False;
+      }
+      else if ( ( vL.type() == QVariant::Date && vR.type() == QVariant::Date ) )
+      {
+        const QDate dL = QgsExpressionUtils::getDateValue( vL, parent );
+        ENSURE_NO_EVAL_ERROR;
+        const QDate dR = QgsExpressionUtils::getDateValue( vR, parent );
+        ENSURE_NO_EVAL_ERROR;
+        return compare( dR.daysTo( dL ) ) ? TVL_True : TVL_False;
+      }
+      else if ( ( vL.type() == QVariant::Time && vR.type() == QVariant::Time ) )
+      {
+        const QTime dL = QgsExpressionUtils::getTimeValue( vL, parent );
+        ENSURE_NO_EVAL_ERROR;
+        const QTime dR = QgsExpressionUtils::getTimeValue( vR, parent );
+        ENSURE_NO_EVAL_ERROR;
+        return compare( dR.msecsTo( dL ) ) ? TVL_True : TVL_False;
+      }
       else if ( ( vL.type() != QVariant::String || vR.type() != QVariant::String ) &&
                 QgsExpressionUtils::isDoubleSafe( vL ) && QgsExpressionUtils::isDoubleSafe( vR ) )
       {
