Are directive arguments checked in validation

[MichaelJCompton]

I thought the following example would result in validation errors, but it passes without error.

Are directive arguments not checked by validation? ...or have I done something silly?

package main

import (
	"github.com/vektah/gqlparser/ast"
	"github.com/vektah/gqlparser/parser"
	"github.com/vektah/gqlparser/validator"
)

func main() {
	schema := `
scalar Int
directive @foo(bla: Int!) on FIELD_DEFINITION

type P {
	f: Int @foo(bla: "asdf")
	g: Int @foo(notblaa: "asdf")
	h: Int @foo
}
`

	doc, gqlErr := parser.ParseSchema(&ast.Source{Input: schema})
	if gqlErr != nil {
		panic(gqlErr)
	}

	_, gqlErr = validator.ValidateSchemaDocument(doc)
	if gqlErr != nil {
		panic(gqlErr)
	}
}