Simplify string formatting (#4757)

7 files changed, 10 insertions, 10 deletions

diff --git a/src/cryptography/hazmat/primitives/ciphers/algorithms.py b/src/cryptography/hazmat/primitives/ciphers/algorithms.py
index 1f49fd9d..f4d5160b 100644
--- a/src/cryptography/hazmat/primitives/ciphers/algorithms.py
+++ b/src/cryptography/hazmat/primitives/ciphers/algorithms.py
@@ -17,7 +17,7 @@ def _verify_key_size(algorithm, key):
 
     # Verify that the key size matches the expected key size
     if len(key) * 8 not in algorithm.key_sizes:
-        raise ValueError("Invalid key size ({0}) for {1}.".format(
+        raise ValueError("Invalid key size ({}) for {}.".format(
             len(key) * 8, algorithm.name
         ))
     return key
diff --git a/src/cryptography/hazmat/primitives/ciphers/base.py b/src/cryptography/hazmat/primitives/ciphers/base.py
index f8570414..4d5f8d60 100644
--- a/src/cryptography/hazmat/primitives/ciphers/base.py
+++ b/src/cryptography/hazmat/primitives/ciphers/base.py
@@ -179,7 +179,7 @@ class _AEADCipherContext(object):
         self._bytes_processed += data_size
         if self._bytes_processed > self._ctx._mode._MAX_ENCRYPTED_BYTES:
             raise ValueError(
-                "{0} has a maximum encrypted byte limit of {1}".format(
+                "{} has a maximum encrypted byte limit of {}".format(
                     self._ctx._mode.name, self._ctx._mode._MAX_ENCRYPTED_BYTES
                 )
             )
@@ -217,7 +217,7 @@ class _AEADCipherContext(object):
         self._aad_bytes_processed += len(data)
         if self._aad_bytes_processed > self._ctx._mode._MAX_AAD_BYTES:
             raise ValueError(
-                "{0} has a maximum AAD byte limit of {1}".format(
+                "{} has a maximum AAD byte limit of {}".format(
                     self._ctx._mode.name, self._ctx._mode._MAX_AAD_BYTES
                 )
             )
diff --git a/src/cryptography/hazmat/primitives/ciphers/modes.py b/src/cryptography/hazmat/primitives/ciphers/modes.py
index ad91a6e1..78fa1c48 100644
--- a/src/cryptography/hazmat/primitives/ciphers/modes.py
+++ b/src/cryptography/hazmat/primitives/ciphers/modes.py
@@ -72,7 +72,7 @@ def _check_aes_key_length(self, algorithm):
 
 def _check_iv_length(self, algorithm):
     if len(self.initialization_vector) * 8 != algorithm.block_size:
-        raise ValueError("Invalid IV size ({0}) for {1}.".format(
+        raise ValueError("Invalid IV size ({}) for {}.".format(
             len(self.initialization_vector), self.name
         ))
 
@@ -178,7 +178,7 @@ class CTR(object):
     def validate_for_algorithm(self, algorithm):
         _check_aes_key_length(self, algorithm)
         if len(self.nonce) * 8 != algorithm.block_size:
-            raise ValueError("Invalid nonce size ({0}) for {1}.".format(
+            raise ValueError("Invalid nonce size ({}) for {}.".format(
                 len(self.nonce), self.name
             ))
 
@@ -205,7 +205,7 @@ class GCM(object):
                 raise ValueError("min_tag_length must be >= 4")
             if len(tag) < min_tag_length:
                 raise ValueError(
-                    "Authentication tag must be {0} bytes or longer.".format(
+                    "Authentication tag must be {} bytes or longer.".format(
                         min_tag_length)
                 )
         self._tag = tag
diff --git a/src/cryptography/hazmat/primitives/kdf/concatkdf.py b/src/cryptography/hazmat/primitives/kdf/concatkdf.py
index 65b25cdc..7cb63856 100644
--- a/src/cryptography/hazmat/primitives/kdf/concatkdf.py
+++ b/src/cryptography/hazmat/primitives/kdf/concatkdf.py
@@ -24,7 +24,7 @@ def _common_args_checks(algorithm, length, otherinfo):
     max_length = algorithm.digest_size * (2 ** 32 - 1)
     if length > max_length:
         raise ValueError(
-            "Can not derive keys larger than {0} bits.".format(
+            "Can not derive keys larger than {} bits.".format(
                 max_length
             ))
     if otherinfo is not None:
diff --git a/src/cryptography/hazmat/primitives/kdf/hkdf.py b/src/cryptography/hazmat/primitives/kdf/hkdf.py
index 307f91cc..01f0f288 100644
--- a/src/cryptography/hazmat/primitives/kdf/hkdf.py
+++ b/src/cryptography/hazmat/primitives/kdf/hkdf.py
@@ -68,7 +68,7 @@ class HKDFExpand(object):
 
         if length > max_length:
             raise ValueError(
-                "Can not derive keys larger than {0} octets.".format(
+                "Can not derive keys larger than {} octets.".format(
                     max_length
                 ))
 
diff --git a/src/cryptography/hazmat/primitives/kdf/pbkdf2.py b/src/cryptography/hazmat/primitives/kdf/pbkdf2.py
index a47b7bbc..07d8ac67 100644
--- a/src/cryptography/hazmat/primitives/kdf/pbkdf2.py
+++ b/src/cryptography/hazmat/primitives/kdf/pbkdf2.py
@@ -24,7 +24,7 @@ class PBKDF2HMAC(object):
 
         if not backend.pbkdf2_hmac_supported(algorithm):
             raise UnsupportedAlgorithm(
-                "{0} is not supported for PBKDF2 by this backend.".format(
+                "{} is not supported for PBKDF2 by this backend.".format(
                     algorithm.name),
                 _Reasons.UNSUPPORTED_HASH
             )
diff --git a/src/cryptography/hazmat/primitives/kdf/x963kdf.py b/src/cryptography/hazmat/primitives/kdf/x963kdf.py
index fd9d125e..9eb50b0f 100644
--- a/src/cryptography/hazmat/primitives/kdf/x963kdf.py
+++ b/src/cryptography/hazmat/primitives/kdf/x963kdf.py
@@ -26,7 +26,7 @@ class X963KDF(object):
         max_len = algorithm.digest_size * (2 ** 32 - 1)
         if length > max_len:
             raise ValueError(
-                "Can not derive keys larger than {0} bits.".format(max_len))
+                "Can not derive keys larger than {} bits.".format(max_len))
         if sharedinfo is not None:
             utils._check_bytes("sharedinfo", sharedinfo)