vitess.io/vitess@v0.16.2/go/vt/vtgate/planbuilder/expression_converter_test.go (about)

     1  /*
     2  Copyright 2020 The Vitess Authors.
     3  
     4  Licensed under the Apache License, Version 2.0 (the "License");
     5  you may not use this file except in compliance with the License.
     6  You may obtain a copy of the License at
     7  
     8      http://www.apache.org/licenses/LICENSE-2.0
     9  
    10  Unless required by applicable law or agreed to in writing, software
    11  distributed under the License is distributed on an "AS IS" BASIS,
    12  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13  See the License for the specific language governing permissions and
    14  limitations under the License.
    15  */
    16  
    17  package planbuilder
    18  
    19  import (
    20  	"testing"
    21  
    22  	"github.com/stretchr/testify/require"
    23  
    24  	"vitess.io/vitess/go/mysql/collations"
    25  	"vitess.io/vitess/go/vt/sqlparser"
    26  	"vitess.io/vitess/go/vt/vtgate/evalengine"
    27  )
    28  
    29  func e(in ...evalengine.Expr) []evalengine.Expr {
    30  	return in
    31  }
    32  
    33  func TestConversion(t *testing.T) {
    34  	type queriesWithExpectations struct {
    35  		expressionsIn  string
    36  		expressionsOut []evalengine.Expr
    37  	}
    38  
    39  	queries := []queriesWithExpectations{{
    40  		expressionsIn:  "1",
    41  		expressionsOut: e(evalengine.NewLiteralInt(1)),
    42  	}, {
    43  		expressionsIn:  "@@foo",
    44  		expressionsOut: e(evalengine.NewColumn(0, collations.TypedCollation{})),
    45  	}}
    46  
    47  	for _, tc := range queries {
    48  		t.Run(tc.expressionsIn, func(t *testing.T) {
    49  			statement, err := sqlparser.Parse("select " + tc.expressionsIn)
    50  			require.NoError(t, err)
    51  			slct := statement.(*sqlparser.Select)
    52  			exprs := extract(slct.SelectExprs)
    53  			ec := &expressionConverter{}
    54  			var result []evalengine.Expr
    55  			for _, expr := range exprs {
    56  				evalExpr, err := ec.convert(expr, false, false)
    57  				require.NoError(t, err)
    58  				result = append(result, evalExpr)
    59  			}
    60  			require.Equal(t, tc.expressionsOut, result)
    61  		})
    62  	}
    63  }
    64  
    65  func extract(in sqlparser.SelectExprs) []sqlparser.Expr {
    66  	var result []sqlparser.Expr
    67  	for _, expr := range in {
    68  		result = append(result, expr.(*sqlparser.AliasedExpr).Expr)
    69  	}
    70  	return result
    71  }