various sanding everywhere towards building the tookit

token/invocation/invocation.go

@@ -102,34 +102,38 @@ func New(iss, sub did.DID, cmd command.Command, prf []cid.Cid, opts ...Option) (
 	return &tkn, nil
 }
 
-func (t *Token) ExecutionAllowed(loader DelegationLoader) (bool, error) {
+func (t *Token) ExecutionAllowed(loader delegation.Loader) error {
 	return t.executionAllowed(loader, t.arguments)
 }
 
-func (t *Token) ExecutionAllowedWithArgsHook(loader DelegationLoader, hook func(*args.Args) *args.Args) (bool, error) {
-	return t.executionAllowed(loader, hook(t.arguments))
+func (t *Token) ExecutionAllowedWithArgsHook(loader delegation.Loader, hook func(args args.ReadOnly) (*args.Args, error)) error {
+	newArgs, err := hook(t.arguments.ReadOnly())
+	if err != nil {
+		return err
+	}
+	return t.executionAllowed(loader, newArgs)
 }
 
-func (t *Token) executionAllowed(loader DelegationLoader, arguments *args.Args) (bool, error) {
+func (t *Token) executionAllowed(loader delegation.Loader, arguments *args.Args) error {
 	delegations, err := t.loadProofs(loader)
 	if err != nil {
 		// All referenced delegations must be available - 4b
-		return false, err
+		return err
 	}
 
 	if err := t.verifyProofs(delegations); err != nil {
-		return false, err
+		return err
 	}
 
 	if err := t.verifyTimeBound(delegations); err != nil {
-		return false, err
+		return err
 	}
 
 	if err := t.verifyArgs(delegations, arguments); err != nil {
-		return false, err
+		return err
 	}
 
-	return true, nil
+	return nil
 }
 
 // Issuer returns the did.DID representing the Token's issuer.
@@ -154,8 +158,8 @@ func (t *Token) Command() command.Command {
 
 // Arguments returns the arguments to be used when the command is
 // invoked.
-func (t *Token) Arguments() *args.Args {
-	return t.arguments
+func (t *Token) Arguments() args.ReadOnly {
+	return t.arguments.ReadOnly()
 }
 
 // Proof() returns the ordered list of cid.Cid which reference the
@@ -225,7 +229,7 @@ func (t *Token) validate() error {
 	return errs
 }
 
-func (t *Token) loadProofs(loader DelegationLoader) (res []*delegation.Token, err error) {
+func (t *Token) loadProofs(loader delegation.Loader) (res []*delegation.Token, err error) {
 	res = make([]*delegation.Token, len(t.proof))
 	for i, c := range t.proof {
 		res[i], err = loader.GetDelegation(c)

token/invocation/invocation_test.go

@@ -5,13 +5,12 @@ import (
 
 	"github.com/ipfs/go-cid"
 	"github.com/stretchr/testify/require"
+
 	"github.com/ucan-wg/go-ucan/did/didtest"
 	"github.com/ucan-wg/go-ucan/pkg/args"
 	"github.com/ucan-wg/go-ucan/pkg/command"
 	"github.com/ucan-wg/go-ucan/token/delegation/delegationtest"
 	"github.com/ucan-wg/go-ucan/token/invocation"
-
-	"github.com/stretchr/testify/assert"
 )
 
 const (
@@ -118,7 +117,7 @@ func TestToken_ExecutionAllowed(t *testing.T) {
 	})
 }
 
-func test(t *testing.T, persona didtest.Persona, cmd command.Command, args *args.Args, prf []cid.Cid, opts ...invocation.Option) (bool, error) {
+func test(t *testing.T, persona didtest.Persona, cmd command.Command, args *args.Args, prf []cid.Cid, opts ...invocation.Option) error {
 	t.Helper()
 
 	tkn, err := invocation.New(persona.DID(t), didtest.PersonaAlice.DID(t), cmd, prf, opts...)
@@ -131,13 +130,11 @@ func test(t *testing.T, persona didtest.Persona, cmd command.Command, args *args
 }
 
 func testFails(t *testing.T, expErr error, persona didtest.Persona, cmd command.Command, args *args.Args, prf []cid.Cid, opts ...invocation.Option) {
-	ok, err := test(t, persona, cmd, args, prf, opts...)
+	err := test(t, persona, cmd, args, prf, opts...)
 	require.ErrorIs(t, err, expErr)
-	assert.False(t, ok)
 }
 
 func testPasses(t *testing.T, persona didtest.Persona, cmd command.Command, args *args.Args, prf []cid.Cid, opts ...invocation.Option) {
-	ok, err := test(t, persona, cmd, args, prf, opts...)
+	err := test(t, persona, cmd, args, prf, opts...)
 	require.NoError(t, err)
-	assert.True(t, ok)
 }

token/invocation/proof.go

@@ -4,8 +4,6 @@ import (
 	"fmt"
 	"time"
 
-	"github.com/ipfs/go-cid"
-
 	"github.com/ucan-wg/go-ucan/pkg/args"
 	"github.com/ucan-wg/go-ucan/pkg/policy"
 	"github.com/ucan-wg/go-ucan/token/delegation"
@@ -49,10 +47,6 @@ import (
 //     a. The policy must "match" the arguments. (verifyArgs below)
 //     b. The nonce (if present) is not reused. (out of scope for go-ucan)
 
-type DelegationLoader interface {
-	GetDelegation(cid cid.Cid) (*delegation.Token, error)
-}
-
 // verifyProofs controls that the proof chain allows the invocation:
 // - principal alignment
 // - command alignment