Fix commented-out unit tests.

I commented out this test while writing #45. Split the Codes function so we can
plumb in a time step for testing, and update the test. This does not change the
observed behaviour for the user.

gauth/gauth.go

@@ -17,34 +17,40 @@ import (
  "github.com/creachadair/otp/otpauth"
 )
 
-// IndexNow returns the current 30-second time slice index, and the number of
-// seconds remaining until it ends.
-func IndexNow() (int64, int) {
+// IndexNow returns the current 30-second time step, and the number of seconds
+// remaining until it ends.
+func IndexNow() (uint64, int) {
  time := time.Now().Unix()
- return time / 30, int(time % 30)
+ return uint64(time / 30), int(time % 30)
 }
 
 // Codes returns the previous, current, and next codes from u.
 func Codes(u *otpauth.URL) (prev, curr, next string, _ error) {
+ var ts uint64
+ if u.Period > 0 {
+ ts = otp.TimeWindow(u.Period)()
+ } else {
+ ts, _ = IndexNow()
+ }
+ return CodesAtTimeStep(u, ts)
+}
+
+// CodesAtTimeStep returns the previous, current, and next codes from u at the
+// given time step value.
+func CodesAtTimeStep(u *otpauth.URL, timeStep uint64) (prev, curr, next string, _ error) {
  if u.Type != "totp" {
  return "", "", "", fmt.Errorf("unsupported type: %q", u.Type)
  } else if u.Algorithm != "" && u.Algorithm != "SHA1" {
  return "", "", "", fmt.Errorf("unsupported algorithm: %q", u.Algorithm)
  }
 
  cfg := otp.Config{Digits: u.Digits}
- var ts uint64
- if u.Period > 0 {
- ts = otp.TimeWindow(u.Period)()
- } else {
- ts = otp.TimeWindow(30)()
- }
  if err := cfg.ParseKey(u.RawSecret); err != nil {
  return "", "", "", fmt.Errorf("invalid secret: %v", err)
  }
- prev = cfg.HOTP(ts - 1)
- curr = cfg.HOTP(ts)
- next = cfg.HOTP(ts + 1)
+ prev = cfg.HOTP(timeStep - 1)
+ curr = cfg.HOTP(timeStep)
+ next = cfg.HOTP(timeStep + 1)
  return
 }
 

gauth/gauth_test.go

@@ -4,14 +4,14 @@ import (
  "bytes"
  "testing"
 
+ "github.com/creachadair/otp/otpauth"
  "github.com/pcarrier/gauth/gauth"
 )
 
-/* TODO: Update this test.
 func TestCodes(t *testing.T) {
  tests := []struct {
  secret string
- index int64
+ index uint64
  want string
  fail bool
  }{
@@ -22,14 +22,15 @@ func TestCodes(t *testing.T) {
  {"blargh!", 123, "", true},
  }
  for _, test := range tests {
- _, got, _, err := gauth.Codes(test.secret, test.index)
+ u := &otpauth.URL{Type: "totp", RawSecret: test.secret}
+ _, got, _, err := gauth.CodesAtTimeStep(u, test.index)
  if err != nil && !test.fail {
- t.Errorf("Code(%q, %d): unexpected error: %v", test.secret, test.index, err)
+ t.Errorf("Codes(%q) at %d: unexpected error: %v", u, test.index, err)
  } else if got != test.want {
- t.Errorf("Code(%q, %d): got %q, want %q", test.secret, test.index, got, test.want)
+ t.Errorf("Codes(%q) at %d: got %q, want %q", u, test.index, got, test.want)
  }
  }
-} */
+}
 
 //go:generate openssl enc -aes-128-cbc -md sha256 -pass pass:x -in testdata/plaintext.csv -out testdata/encrypted.csv