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m-kuhnm-kuhn
authoredDec 16, 2019
Merge pull request #33333 from lbartoletti/expression-is_empty
Add expressions is_empty(geom) is_empty_or_null(geom)
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ltr-3_40final-3_12_0
2 parents c235c4c + c7fca82 commit 3b4437b

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‎resources/function_help/json/is_empty

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{
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"name": "is_empty",
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"type": "function",
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"description": "Returns true if a geometry is empty (without coordinates), false if the geometry is not empty and NULL if there is no geometry. See also `is_empty_or_null`.",
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"arguments": [ {"arg":"geom","description":"a geometry"}],
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"examples": [ { "expression":"is_empty(geom_from_wkt('LINESTRING(0 0, 1 1, 2 2)'))", "returns":"false"},
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{ "expression":"is_empty(geom_from_wkt('LINESTRING EMPTY'))", "returns":"true"},
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{ "expression":"is_empty(geom_from_wkt('POINT(7 4)'))", "returns":"false"},
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{ "expression":"is_empty(geom_from_wkt('POINT EMPTY'))", "returns":"true"} ]
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}

‎resources/function_help/json/is_empty_or_null

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{
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"name": "is_empty_or_null",
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"type": "function",
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"description": "Returns true if a geometry is NULL or empty (without coordinates) or false otherwise. This function is like the expression '$geometry IS NULL or is_empty($geometry)'",
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"arguments": [ {"arg":"geom","description":"a geometry"}],
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"examples": [ { "expression":"is_empty_or_null(NULL)", "returns":"true"},
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{ "expression":"is_empty_or_null(geom_from_wkt('LINESTRING(0 0, 1 1, 2 2)'))", "returns":"false"},
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{ "expression":"is_empty_or_null(geom_from_wkt('LINESTRING EMPTY'))", "returns":"true"},
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{ "expression":"is_empty_or_null(geom_from_wkt('POINT(7 4)'))", "returns":"false"},
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{ "expression":"is_empty_or_null(geom_from_wkt('POINT EMPTY'))", "returns":"true"} ]
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}

‎src/core/expression/qgsexpressionfunction.cpp

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@@ -3124,6 +3124,24 @@ static QVariant fcnIsClosed( const QVariantList &values, const QgsExpressionCont
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return QVariant::fromValue( curve->isClosed() );
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}
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static QVariant fcnIsEmpty( const QVariantList &values, const QgsExpressionContext *, QgsExpression *parent, const QgsExpressionNodeFunction * )
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{
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QgsGeometry fGeom = QgsExpressionUtils::getGeometry( values.at( 0 ), parent );
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if ( fGeom.isNull() )
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return QVariant();
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return QVariant::fromValue( fGeom.isEmpty() );
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}
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static QVariant fcnIsEmptyOrNull( const QVariantList &values, const QgsExpressionContext *, QgsExpression *parent, const QgsExpressionNodeFunction * )
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{
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if ( values.at( 0 ).isNull() )
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return QVariant::fromValue( true );
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QgsGeometry fGeom = QgsExpressionUtils::getGeometry( values.at( 0 ), parent );
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return QVariant::fromValue( fGeom.isNull() || fGeom.isEmpty() );
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}
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static QVariant fcnRelate( const QVariantList &values, const QgsExpressionContext *, QgsExpression *parent, const QgsExpressionNodeFunction * )
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{
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if ( values.length() < 2 || values.length() > 3 )
@@ -5661,6 +5679,8 @@ const QList<QgsExpressionFunction *> &QgsExpression::Functions()
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<< new QgsStaticExpressionFunction( QStringLiteral( "bounds_width" ), QgsExpressionFunction::ParameterList() << QgsExpressionFunction::Parameter( QStringLiteral( "geom" ) ), fcnBoundsWidth, QStringLiteral( "GeometryGroup" ) )
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<< new QgsStaticExpressionFunction( QStringLiteral( "bounds_height" ), QgsExpressionFunction::ParameterList() << QgsExpressionFunction::Parameter( QStringLiteral( "geom" ) ), fcnBoundsHeight, QStringLiteral( "GeometryGroup" ) )
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<< new QgsStaticExpressionFunction( QStringLiteral( "is_closed" ), QgsExpressionFunction::ParameterList() << QgsExpressionFunction::Parameter( QStringLiteral( "geom" ) ), fcnIsClosed, QStringLiteral( "GeometryGroup" ) )
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<< new QgsStaticExpressionFunction( QStringLiteral( "is_empty" ), QgsExpressionFunction::ParameterList() << QgsExpressionFunction::Parameter( QStringLiteral( "geom" ) ), fcnIsEmpty, QStringLiteral( "GeometryGroup" ) )
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<< new QgsStaticExpressionFunction( QStringLiteral( "is_empty_or_null" ), QgsExpressionFunction::ParameterList() << QgsExpressionFunction::Parameter( QStringLiteral( "geom" ) ), fcnIsEmptyOrNull, QStringLiteral( "GeometryGroup" ), QString(), false, QSet<QString>(), false, QStringList(), true )
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<< new QgsStaticExpressionFunction( QStringLiteral( "convex_hull" ), QgsExpressionFunction::ParameterList() << QgsExpressionFunction::Parameter( QStringLiteral( "geometry" ) ), fcnConvexHull, QStringLiteral( "GeometryGroup" ), QString(), false, QSet<QString>(), false, QStringList() << QStringLiteral( "convexHull" ) )
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<< new QgsStaticExpressionFunction( QStringLiteral( "oriented_bbox" ), QgsExpressionFunction::ParameterList()
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<< QgsExpressionFunction::Parameter( QStringLiteral( "geometry" ) ),

‎tests/src/core/testqgsexpression.cpp

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@@ -985,6 +985,18 @@ class TestQgsExpression: public QObject
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QTest::newRow( "is_closed multiline" ) << "is_closed(geom_from_wkt('MultiLineString ((6501338.13976828 4850981.51459331, 6501343.09036573 4850984.01453377, 6501338.13976828 4850988.96491092, 6501335.63971657 4850984.01453377, 6501338.13976828 4850981.51459331))'))" << false << QVariant( true );
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QTest::newRow( "is_closed multiline" ) << "is_closed(geom_from_wkt('MultiLineString ((6501338.13976828 4850981.51459331, 6501343.09036573 4850984.01453377, 6501338.13976828 4850988.96491092, 6501335.63971657 4850984.01453377, 6501438.13976828 4850981.51459331))'))" << false << QVariant( false );
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QTest::newRow( "is_closed multiline" ) << "is_closed(geom_from_wkt('MultiLineString EMPTY'))" << false << QVariant();
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QTest::newRow( "is_empty not geom" ) << "is_empty('g')" << true << QVariant();
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QTest::newRow( "is_empty null" ) << "is_empty(NULL)" << false << QVariant();
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QTest::newRow( "is_empty point" ) << "is_empty(geom_from_wkt('POINT(1 2)'))" << false << QVariant( false );
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QTest::newRow( "is_empty empty point" ) << "is_empty(geom_from_wkt('POINT EMPTY'))" << false << QVariant( true );
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QTest::newRow( "is_empty polygon" ) << "is_empty(geom_from_wkt('POLYGON((-1 -1, 4 0, 4 2, 0 2, -1 -1))'))" << false << QVariant( false );
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QTest::newRow( "is_empty empty polygon" ) << "is_empty(geom_from_wkt('POLYGON EMPTY'))" << false << QVariant( true );
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QTest::newRow( "is_empty_or_null not geom" ) << "is_empty_or_null('g')" << true << QVariant();
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QTest::newRow( "is_empty_or_null null" ) << "is_empty_or_null(NULL)" << false << QVariant( true );
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QTest::newRow( "is_empty_or_null point" ) << "is_empty_or_null(geom_from_wkt('POINT(1 2)'))" << false << QVariant( false );
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QTest::newRow( "is_empty_or_null empty point" ) << "is_empty_or_null(geom_from_wkt('POINT EMPTY'))" << false << QVariant( true );
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QTest::newRow( "is_empty_or_null polygon" ) << "is_empty_or_null(geom_from_wkt('POLYGON((-1 -1, 4 0, 4 2, 0 2, -1 -1))'))" << false << QVariant( false );
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QTest::newRow( "is_empty_or_null empty polygon" ) << "is_empty_or_null(geom_from_wkt('POLYGON EMPTY'))" << false << QVariant( true );
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QTest::newRow( "collect_geometries none" ) << "geom_to_wkt(collect_geometries())" << false << QVariant( "" );
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QTest::newRow( "collect_geometries not" ) << "geom_to_wkt(collect_geometries(45))" << true << QVariant();
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QTest::newRow( "collect_geometries one" ) << "geom_to_wkt(collect_geometries(make_point(4,5)))" << false << QVariant( "MultiPoint ((4 5))" );

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