Fix OTP compatibility (#934)

Closes #932.

lib/hex/stdlib.ex

@@ -117,53 +117,57 @@ defmodule Hex.Stdlib do
   end
 
   # TODO: Remove this once we require OTP 22.1
-  if Code.ensure_loaded?(:crypto) and function_exported?(:crypto, :mac, 4) do
-    def crypto_hmac(type, key, data), do: :crypto.mac(:hmac, type, key, data)
-  else
-    def crypto_hmac(type, key, data), do: :crypto.hmac(type, key, data)
+  def crypto_hmac(type, key, data) do
+    if Code.ensure_loaded?(:crypto) and function_exported?(:crypto, :mac, 4) do
+      apply(:crypto, :mac, [:hmac, type, key, data])
+    else
+      apply(:crypto, :hmac, [type, key, data])
+    end
   end
 
   # TODO: Remove this once we require OTP 22.0
-  if Code.ensure_loaded?(:crypto) and function_exported?(:crypto, :crypto_one_time, 5) do
-    def crypto_one_time_encrypt(cipher, key, iv, data),
-      do: :crypto.crypto_one_time(cipher, key, iv, data, true)
-  else
-    def crypto_one_time_encrypt(cipher, key, iv, data),
-      do: :crypto.block_encrypt(cipher, key, iv, data)
+  def crypto_one_time_encrypt(cipher, key, iv, data) do
+    if Code.ensure_loaded?(:crypto) and function_exported?(:crypto, :crypto_one_time, 5) do
+      apply(:crypto, :crypto_one_time, [cipher, key, iv, data, true])
+    else
+      apply(:crypto, :block_encrypt, [cipher, key, iv, data])
+    end
   end
 
   # TODO: Remove this once we require OTP 22.0
-  if Code.ensure_loaded?(:crypto) and function_exported?(:crypto, :crypto_one_time, 5) do
-    def crypto_one_time_decrypt(cipher, key, iv, data),
-      do: :crypto.crypto_one_time(cipher, key, iv, data, false)
-  else
-    def crypto_one_time_decrypt(cipher, key, iv, data),
-      do: :crypto.block_decrypt(cipher, key, iv, data)
+  def crypto_one_time_decrypt(cipher, key, iv, data) do
+    if Code.ensure_loaded?(:crypto) and function_exported?(:crypto, :crypto_one_time, 5) do
+      apply(:crypto, :crypto_one_time, [cipher, key, iv, data, false])
+    else
+      apply(:crypto, :block_decrypt, [cipher, key, iv, data])
+    end
   end
 
   # TODO: Remove this once we require OTP 22.0
-  if Code.ensure_loaded?(:crypto) and function_exported?(:crypto, :crypto_one_time_aead, 7) do
-    def crypto_one_time_aead_encrypt(cipher, key, iv, plain_text, aad),
-      do: :crypto.crypto_one_time_aead(cipher, key, iv, plain_text, aad, true)
-  else
-    def crypto_one_time_aead_encrypt(_cipher, key, iv, plain_text, aad),
-      do: :crypto.block_encrypt(:aes_gcm, key, iv, {aad, plain_text})
+  def crypto_one_time_aead_encrypt(cipher, key, iv, plain_text, aad) do
+    if Code.ensure_loaded?(:crypto) and function_exported?(:crypto, :crypto_one_time_aead, 5) do
+      apply(:crypto, :crypto_one_time_aead, [cipher, key, iv, plain_text, aad, true])
+    else
+      apply(:crypto, :block_encrypt, [:aes_gcm, key, iv, {aad, plain_text}])
+    end
   end
 
   # TODO: Remove this once we require OTP 22.0
-  if Code.ensure_loaded?(:crypto) and function_exported?(:crypto, :crypto_one_time_aead, 7) do
-    def crypto_one_time_aead_decrypt(cipher, key, iv, cipher_text, aad, cipher_tag),
-      do: :crypto.crypto_one_time_aead(cipher, key, iv, cipher_text, aad, cipher_tag, false)
-  else
-    def crypto_one_time_aead_decrypt(_cipher, key, iv, cipher_text, aad, cipher_tag),
-      do: :crypto.block_decrypt(:aes_gcm, key, iv, {aad, cipher_text, cipher_tag})
+  def crypto_one_time_aead_decrypt(cipher, key, iv, cipher_text, aad, cipher_tag) do
+    if Code.ensure_loaded?(:crypto) and function_exported?(:crypto, :crypto_one_time_aead, 5) do
+      apply(:crypto, :crypto_one_time_aead, [cipher, key, iv, cipher_text, aad, cipher_tag, false])
+    else
+      apply(:crypto, :block_decrypt, [:aes_gcm, key, iv, {aad, cipher_text, cipher_tag}])
+    end
   end
 
   # TODO: Remove this once we require OTP 22.0
-  if Code.ensure_loaded?(:ssl) and function_exported?(:ssl, :cipher_suites, 3) do
-    def ssl_cipher_suites(string_type),
-      do: :ssl.cipher_suites(:all, hd(:ssl.versions()[:supported]), string_type)
-  else
-    def ssl_cipher_suites(string_type), do: :ssl.cipher_suites(string_type)
+  def ssl_cipher_suites(string_type) do
+    if Code.ensure_loaded?(:ssl) and function_exported?(:ssl, :cipher_suites, 3) do
+      [ssl_version | _] = :ssl.versions()[:supported]
+      apply(:ssl, :cipher_suites, [:all, ssl_version, string_type])
+    else
+      apply(:ssl, :cipher_suites, [string_type])
+    end
   end
 end