DockerCLI/vendor/gotest.tools/v3/assert/cmp/result.go

111 lines
2.9 KiB
Go

package cmp
import (
"bytes"
"fmt"
"go/ast"
"reflect"
"text/template"
"gotest.tools/v3/internal/source"
)
// A Result of a [Comparison].
type Result interface {
Success() bool
}
// StringResult is an implementation of [Result] that reports the error message
// string verbatim and does not provide any templating or formatting of the
// message.
type StringResult struct {
success bool
message string
}
// Success returns true if the comparison was successful.
func (r StringResult) Success() bool {
return r.success
}
// FailureMessage returns the message used to provide additional information
// about the failure.
func (r StringResult) FailureMessage() string {
return r.message
}
// ResultSuccess is a constant which is returned by a [Comparison] to
// indicate success.
var ResultSuccess = StringResult{success: true}
// ResultFailure returns a failed [Result] with a failure message.
func ResultFailure(message string) StringResult {
return StringResult{message: message}
}
// ResultFromError returns [ResultSuccess] if err is nil. Otherwise [ResultFailure]
// is returned with the error message as the failure message.
func ResultFromError(err error) Result {
if err == nil {
return ResultSuccess
}
return ResultFailure(err.Error())
}
type templatedResult struct {
template string
data map[string]interface{}
}
func (r templatedResult) Success() bool {
return false
}
func (r templatedResult) FailureMessage(args []ast.Expr) string {
msg, err := renderMessage(r, args)
if err != nil {
return fmt.Sprintf("failed to render failure message: %s", err)
}
return msg
}
func (r templatedResult) UpdatedExpected(stackIndex int) error {
// TODO: would be nice to have structured data instead of a map
return source.UpdateExpectedValue(stackIndex+1, r.data["x"], r.data["y"])
}
// ResultFailureTemplate returns a [Result] with a template string and data which
// can be used to format a failure message. The template may access data from .Data,
// the comparison args with the callArg function, and the formatNode function may
// be used to format the call args.
func ResultFailureTemplate(template string, data map[string]interface{}) Result {
return templatedResult{template: template, data: data}
}
func renderMessage(result templatedResult, args []ast.Expr) (string, error) {
tmpl := template.New("failure").Funcs(template.FuncMap{
"formatNode": source.FormatNode,
"callArg": func(index int) ast.Expr {
if index >= len(args) {
return nil
}
return args[index]
},
// TODO: any way to include this from ErrorIS instead of here?
"notStdlibErrorType": func(typ interface{}) bool {
r := reflect.TypeOf(typ)
return r != stdlibFmtErrorType && r != stdlibErrorNewType
},
})
var err error
tmpl, err = tmpl.Parse(result.template)
if err != nil {
return "", err
}
buf := new(bytes.Buffer)
err = tmpl.Execute(buf, map[string]interface{}{
"Data": result.data,
})
return buf.String(), err
}