yq/pkg/yqlib/operator_subtract.go
2021-09-02 15:26:44 +10:00

94 lines
2.7 KiB
Go

package yqlib
import (
"fmt"
"strconv"
yaml "gopkg.in/yaml.v3"
)
func createSubtractOp(lhs *ExpressionNode, rhs *ExpressionNode) *ExpressionNode {
return &ExpressionNode{Operation: &Operation{OperationType: subtractOpType},
Lhs: lhs,
Rhs: rhs}
}
func subtractAssignOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
return compoundAssignFunction(d, context, expressionNode, createSubtractOp)
}
func subtractOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
log.Debugf("Subtract operator")
return crossFunction(d, context.ReadOnlyClone(), expressionNode, subtract, false)
}
func subtract(d *dataTreeNavigator, context Context, lhs *CandidateNode, rhs *CandidateNode) (*CandidateNode, error) {
lhs.Node = unwrapDoc(lhs.Node)
rhs.Node = unwrapDoc(rhs.Node)
lhsNode := lhs.Node
if lhsNode.Tag == "!!null" {
return lhs.CreateChild(nil, rhs.Node), nil
}
target := lhs.CreateChild(nil, &yaml.Node{})
switch lhsNode.Kind {
case yaml.MappingNode:
return nil, fmt.Errorf("Maps not yet supported for subtraction")
case yaml.SequenceNode:
return nil, fmt.Errorf("Sequences not yet supported for subtraction")
// target.Node.Kind = yaml.SequenceNode
// target.Node.Style = lhsNode.Style
// target.Node.Tag = "!!seq"
// target.Node.Content = append(lhsNode.Content, toNodes(rhs)...)
case yaml.ScalarNode:
if rhs.Node.Kind != yaml.ScalarNode {
return nil, fmt.Errorf("%v (%v) cannot be added to a %v", rhs.Node.Tag, rhs.Path, lhsNode.Tag)
}
target.Node.Kind = yaml.ScalarNode
target.Node.Style = lhsNode.Style
return subtractScalars(target, lhsNode, rhs.Node)
}
return target, nil
}
func subtractScalars(target *CandidateNode, lhs *yaml.Node, rhs *yaml.Node) (*CandidateNode, error) {
if lhs.Tag == "!!str" {
return nil, fmt.Errorf("strings cannot be subtracted")
} else if lhs.Tag == "!!int" && rhs.Tag == "!!int" {
format, lhsNum, err := parseInt(lhs.Value)
if err != nil {
return nil, err
}
_, rhsNum, err := parseInt(rhs.Value)
if err != nil {
return nil, err
}
result := lhsNum - rhsNum
target.Node.Tag = "!!int"
target.Node.Value = fmt.Sprintf(format, result)
} else if (lhs.Tag == "!!int" || lhs.Tag == "!!float") && (rhs.Tag == "!!int" || rhs.Tag == "!!float") {
lhsNum, err := strconv.ParseFloat(lhs.Value, 64)
if err != nil {
return nil, err
}
rhsNum, err := strconv.ParseFloat(rhs.Value, 64)
if err != nil {
return nil, err
}
result := lhsNum - rhsNum
target.Node.Tag = "!!float"
target.Node.Value = fmt.Sprintf("%v", result)
} else {
return nil, fmt.Errorf("%v cannot be added to %v", lhs.Tag, rhs.Tag)
}
return target, nil
}