github.com/dolthub/go-mysql-server@v0.18.0/sql/expression/function/spatial/st_perimeter_test.go (about)

     1  // Copyright 2020-2022 Dolthub, Inc.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package spatial
    16  
    17  import (
    18  	"math"
    19  	"testing"
    20  
    21  	"github.com/stretchr/testify/require"
    22  
    23  	"github.com/dolthub/go-mysql-server/sql"
    24  	"github.com/dolthub/go-mysql-server/sql/expression"
    25  	"github.com/dolthub/go-mysql-server/sql/types"
    26  )
    27  
    28  func TestPerimeter(t *testing.T) {
    29  	t.Run("select perimeter of right triangle", func(t *testing.T) {
    30  		require := require.New(t)
    31  		polygon := types.Polygon{Lines: []types.LineString{{Points: []types.Point{{X: 0, Y: 0}, {X: 0, Y: 1}, {X: 1, Y: 1}, {X: 0, Y: 0}}}}}
    32  		f, err := NewPerimeter(expression.NewLiteral(polygon, types.PolygonType{}))
    33  		require.NoError(err)
    34  
    35  		v, err := f.Eval(sql.NewEmptyContext(), nil)
    36  		require.NoError(err)
    37  		require.Equal(1+1+math.Sqrt2, v)
    38  	})
    39  
    40  	t.Run("select perimeter of unit square", func(t *testing.T) {
    41  		require := require.New(t)
    42  		polygon := types.Polygon{Lines: []types.LineString{{Points: []types.Point{{X: 0, Y: 0}, {X: 0, Y: 1}, {X: 1, Y: 1}, {X: 1, Y: 0}, {X: 0, Y: 0}}}}}
    43  		f, err := NewPerimeter(expression.NewLiteral(polygon, types.PolygonType{}))
    44  		require.NoError(err)
    45  
    46  		v, err := f.Eval(sql.NewEmptyContext(), nil)
    47  		require.NoError(err)
    48  		require.Equal(4.0, v)
    49  	})
    50  
    51  	t.Run("select perimeter of some shape", func(t *testing.T) {
    52  		require := require.New(t)
    53  		polygon := types.Polygon{Lines: []types.LineString{{Points: []types.Point{{X: 1, Y: 2}, {X: 3.2, Y: 4.5}, {X: -12.2, Y: 23}, {X: 55, Y: 88}, {X: 33, Y: 255.123}, {X: 17, Y: 2}, {X: 1, Y: 2}}}}}
    54  		f, err := NewPerimeter(expression.NewLiteral(polygon, types.PolygonType{}))
    55  		require.NoError(err)
    56  
    57  		v, err := f.Eval(sql.NewEmptyContext(), nil)
    58  		require.NoError(err)
    59  		require.Equal(559.0865562863385, v)
    60  	})
    61  
    62  	t.Run("select perimeter of triangle with hole", func(t *testing.T) {
    63  		require := require.New(t)
    64  		line1 := types.LineString{Points: []types.Point{{X: 0, Y: 0}, {X: 0, Y: 3}, {X: 3, Y: 0}, {X: 0, Y: 0}}}
    65  		line2 := types.LineString{Points: []types.Point{{X: 1, Y: 1}, {X: 1, Y: 2}, {X: 2, Y: 1}, {X: 1, Y: 1}}}
    66  		polygon := types.Polygon{Lines: []types.LineString{line1, line2}}
    67  		f, err := NewPerimeter(expression.NewLiteral(polygon, types.PolygonType{}))
    68  		require.NoError(err)
    69  
    70  		v, err := f.Eval(sql.NewEmptyContext(), nil)
    71  		require.NoError(err)
    72  		perimeter1 := 3 + 3 + 3*math.Sqrt2
    73  		perimeter2 := 1 + 1 + math.Sqrt2
    74  		require.Equal(perimeter1+perimeter2, v)
    75  	})
    76  
    77  	t.Run("select perimeter of NULL", func(t *testing.T) {
    78  		require := require.New(t)
    79  		f, err := NewPerimeter(expression.NewLiteral(nil, types.Null))
    80  		require.NoError(err)
    81  
    82  		v, err := f.Eval(sql.NewEmptyContext(), nil)
    83  		require.NoError(err)
    84  		require.Equal(nil, v)
    85  	})
    86  
    87  	t.Run("select length of wrong type", func(t *testing.T) {
    88  		require := require.New(t)
    89  		f, err := NewPerimeter(expression.NewLiteral("abc", types.Text))
    90  		require.NoError(err)
    91  		_, err = f.Eval(sql.NewEmptyContext(), nil)
    92  		require.Error(err)
    93  	})
    94  }