Specific base typespecs (#11449)

* Use specific options for base option typespecs

Each function had `keyword` as the option type, which didn't help guard
against typos or mismatched options.

* Fix padding use in encode/decode identity test

2 files changed, 31 insertions, 17 deletions

diff --git a/lib/elixir/lib/base.ex b/lib/elixir/lib/base.ex
index 2eb2265d4..c902963b6 100644
--- a/lib/elixir/lib/base.ex
+++ b/lib/elixir/lib/base.ex
@@ -92,6 +92,9 @@ defmodule Base do
 
   """
 
+  @type encode_case :: :upper | :lower
+  @type decode_case :: :upper | :lower | :mixed
+
   b16_alphabet = '0123456789ABCDEF'
   b64_alphabet = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/'
   b64url_alphabet = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_'
@@ -267,7 +270,7 @@ defmodule Base do
       "666f6f626172"
 
   """
-  @spec encode16(binary, keyword) :: binary
+  @spec encode16(binary, case: encode_case) :: binary
   def encode16(data, opts \\ []) when is_binary(data) do
     case = Keyword.get(opts, :case, :upper)
     do_encode16(case, data)
@@ -300,7 +303,7 @@ defmodule Base do
       {:ok, "foobar"}
 
   """
-  @spec decode16(binary, keyword) :: {:ok, binary} | :error
+  @spec decode16(binary, case: decode_case) :: {:ok, binary} | :error
   def decode16(string, opts \\ []) do
     {:ok, decode16!(string, opts)}
   rescue
@@ -337,7 +340,7 @@ defmodule Base do
       "foobar"
 
   """
-  @spec decode16!(binary, keyword) :: binary
+  @spec decode16!(binary, case: encode_case) :: binary
   def decode16!(string, opts \\ [])
 
   def decode16!(string, opts) when is_binary(string) and rem(byte_size(string), 2) == 0 do
@@ -367,7 +370,7 @@ defmodule Base do
       "Zm9vYg"
 
   """
-  @spec encode64(binary, keyword) :: binary
+  @spec encode64(binary, padding: boolean) :: binary
   def encode64(data, opts \\ []) when is_binary(data) do
     pad? = Keyword.get(opts, :padding, true)
     do_encode64(data, pad?)
@@ -397,7 +400,7 @@ defmodule Base do
       {:ok, "foob"}
 
   """
-  @spec decode64(binary, keyword) :: {:ok, binary} | :error
+  @spec decode64(binary, ignore: :whitespace, padding: boolean) :: {:ok, binary} | :error
   def decode64(string, opts \\ []) when is_binary(string) do
     {:ok, decode64!(string, opts)}
   rescue
@@ -431,7 +434,7 @@ defmodule Base do
       "foob"
 
   """
-  @spec decode64!(binary, keyword) :: binary
+  @spec decode64!(binary, ignore: :whitespace, padding: boolean) :: binary
   def decode64!(string, opts \\ []) when is_binary(string) do
     pad? = Keyword.get(opts, :padding, true)
     string |> remove_ignored(opts[:ignore]) |> do_decode64(pad?)
@@ -453,7 +456,7 @@ defmodule Base do
       "_3_-_A"
 
   """
-  @spec url_encode64(binary, keyword) :: binary
+  @spec url_encode64(binary, padding: boolean) :: binary
   def url_encode64(data, opts \\ []) when is_binary(data) do
     pad? = Keyword.get(opts, :padding, true)
     do_encode64url(data, pad?)
@@ -481,7 +484,7 @@ defmodule Base do
       {:ok, <<255, 127, 254, 252>>}
 
   """
-  @spec url_decode64(binary, keyword) :: {:ok, binary} | :error
+  @spec url_decode64(binary, ignore: :whitespace, padding: boolean) :: {:ok, binary} | :error
   def url_decode64(string, opts \\ []) when is_binary(string) do
     {:ok, url_decode64!(string, opts)}
   rescue
@@ -513,7 +516,7 @@ defmodule Base do
       <<255, 127, 254, 252>>
 
   """
-  @spec url_decode64!(binary, keyword) :: binary
+  @spec url_decode64!(binary, ignore: :whitespace, padding: boolean) :: binary
   def url_decode64!(string, opts \\ []) when is_binary(string) do
     pad? = Keyword.get(opts, :padding, true)
     string |> remove_ignored(opts[:ignore]) |> do_decode64url(pad?)
@@ -551,7 +554,7 @@ defmodule Base do
       "MZXW6YTBOI"
 
   """
-  @spec encode32(binary, keyword) :: binary
+  @spec encode32(binary, case: encode_case, padding: boolean) :: binary
   def encode32(data, opts \\ []) when is_binary(data) do
     case = Keyword.get(opts, :case, :upper)
     pad? = Keyword.get(opts, :padding, true)
@@ -594,7 +597,7 @@ defmodule Base do
       {:ok, "foobar"}
 
   """
-  @spec decode32(binary, keyword) :: {:ok, binary} | :error
+  @spec decode32(binary, case: decode_case, padding: boolean) :: {:ok, binary} | :error
   def decode32(string, opts \\ []) do
     {:ok, decode32!(string, opts)}
   rescue
@@ -640,7 +643,7 @@ defmodule Base do
       "foobar"
 
   """
-  @spec decode32!(binary, keyword) :: binary
+  @spec decode32!(binary, case: decode_case, padding: boolean) :: binary
   def decode32!(string, opts \\ []) when is_binary(string) do
     case = Keyword.get(opts, :case, :upper)
     pad? = Keyword.get(opts, :padding, true)
@@ -680,7 +683,7 @@ defmodule Base do
       "CPNMUOJ1E8"
 
   """
-  @spec hex_encode32(binary, keyword) :: binary
+  @spec hex_encode32(binary, case: encode_case, padding: boolean) :: binary
   def hex_encode32(data, opts \\ []) when is_binary(data) do
     case = Keyword.get(opts, :case, :upper)
     pad? = Keyword.get(opts, :padding, true)
@@ -724,7 +727,7 @@ defmodule Base do
       {:ok, "foobar"}
 
   """
-  @spec hex_decode32(binary, keyword) :: {:ok, binary} | :error
+  @spec hex_decode32(binary, case: decode_case, padding: boolean) :: {:ok, binary} | :error
   def hex_decode32(string, opts \\ []) do
     {:ok, hex_decode32!(string, opts)}
   rescue
@@ -771,7 +774,7 @@ defmodule Base do
       "foobar"
 
   """
-  @spec hex_decode32!(binary, keyword) :: binary
+  @spec hex_decode32!(binary, case: decode_case, padding: boolean) :: binary
   def hex_decode32!(string, opts \\ []) when is_binary(string) do
     case = Keyword.get(opts, :case, :upper)
     pad? = Keyword.get(opts, :padding, true)
diff --git a/lib/elixir/test/elixir/base_test.exs b/lib/elixir/test/elixir/base_test.exs
index 78cc6b5ad..028a47abe 100644
--- a/lib/elixir/test/elixir/base_test.exs
+++ b/lib/elixir/test/elixir/base_test.exs
@@ -799,10 +799,21 @@ defmodule BaseTest do
         |> Enum.shuffle()
         |> IO.iodata_to_binary()
 
+      allowed_opts =
+        encode
+        |> Function.info()
+        |> Keyword.fetch!(:name)
+        |> case do
+          :encode16 -> [:case]
+          :encode64 -> [:padding]
+          :url_encode64 -> [:padding]
+          _ -> [:case, :padding]
+        end
+
       expected =
         data
-        |> encode.(case: encode_case, pad: pad?)
-        |> decode.(case: decode_case, pad: pad?)
+        |> encode.(Keyword.take([case: encode_case, padding: pad?], allowed_opts))
+        |> decode.(Keyword.take([case: decode_case, padding: pad?], allowed_opts))
 
       assert data == expected,
              "identity did not match for #{inspect(data)} when #{inspect(encode)} (#{encode_case})"