omissis/goarkitect

package expect

import (
    "fmt"
    "os"
    "path/filepath"

    "github.com/omissis/goarkitect/internal/arch/rule"
)

func Exist(opts ...Option) *existExpression {
    expr := &existExpression{}

    expr.applyOptions(opts)

    return expr
}

type existExpression struct {
    baseExpression
}

func (e existExpression) Evaluate(rb rule.Builder) []rule.CoreViolation {
    return e.evaluate(rb, e.doEvaluate, e.getViolation)
}

func (e existExpression) doEvaluate(rb rule.Builder, filePath string) bool {
    if _, err := os.Stat(filePath); err != nil {
        if !os.IsNotExist(err) {
            rb.AddError(err)
        }

        return true
    }

    return false
}

func (e existExpression) getViolation(filePath string) rule.CoreViolation {
    format := "file '%s' does not exist"
    if e.options.negated {
        format = "file '%s' does exist"
    }

    return rule.NewCoreViolation(
        fmt.Sprintf(format, filepath.Base(filePath)),
    )
}