Add credo

.credo.exs

@@ -0,0 +1,72 @@
+%{
+  configs: [
+    %{
+      name: "default",
+      files: %{
+        included: ["lib/", "src/", "web/", "apps/", "test/"],
+        excluded: [~r"/_build/", ~r"/deps/"]
+      },
+      requires: [],
+      strict: true,
+      color: true,
+      checks: [
+        {Credo.Check.Consistency.ExceptionNames},
+        {Credo.Check.Consistency.LineEndings},
+        {Credo.Check.Consistency.MultiAliasImportRequireUse},
+        {Credo.Check.Consistency.ParameterPatternMatching},
+        {Credo.Check.Consistency.SpaceAroundOperators},
+        {Credo.Check.Consistency.SpaceInParentheses},
+        {Credo.Check.Consistency.TabsOrSpaces},
+        {Credo.Check.Design.AliasUsage, false},
+        {Credo.Check.Design.DuplicatedCode, excluded_macros: []},
+        {Credo.Check.Design.TagFIXME},
+        {Credo.Check.Design.TagTODO, false},
+        {Credo.Check.Readability.FunctionNames},
+        {Credo.Check.Readability.LargeNumbers},
+        {Credo.Check.Readability.MaxLineLength, max_length: 100},
+        {Credo.Check.Readability.ModuleAttributeNames},
+        {Credo.Check.Readability.ModuleDoc},
+        {Credo.Check.Readability.ModuleNames},
+        {Credo.Check.Readability.ParenthesesOnZeroArityDefs},
+        {Credo.Check.Readability.ParenthesesInCondition},
+        {Credo.Check.Readability.PredicateFunctionNames},
+        {Credo.Check.Readability.PreferImplicitTry},
+        {Credo.Check.Readability.RedundantBlankLines},
+        {Credo.Check.Readability.Semicolons},
+        {Credo.Check.Readability.SinglePipe, false},
+        {Credo.Check.Readability.SpaceAfterCommas},
+        {Credo.Check.Readability.Specs, false},
+        {Credo.Check.Readability.StringSigils},
+        {Credo.Check.Readability.TrailingBlankLine},
+        {Credo.Check.Readability.TrailingWhiteSpace},
+        {Credo.Check.Readability.VariableNames},
+        {Credo.Check.Refactor.DoubleBooleanNegation},
+        {Credo.Check.Refactor.CondStatements},
+        {Credo.Check.Refactor.CyclomaticComplexity},
+        {Credo.Check.Refactor.FunctionArity},
+        {Credo.Check.Refactor.LongQuoteBlocks},
+        {Credo.Check.Refactor.MatchInCondition},
+        {Credo.Check.Refactor.NegatedConditionsInUnless},
+        {Credo.Check.Refactor.NegatedConditionsWithElse},
+        {Credo.Check.Refactor.Nesting},
+        {Credo.Check.Refactor.PipeChainStart, false},
+        {Credo.Check.Refactor.UnlessWithElse},
+        {Credo.Check.Warning.BoolOperationOnSameValues},
+        {Credo.Check.Warning.IExPry},
+        {Credo.Check.Warning.IoInspect},
+        {Credo.Check.Warning.LazyLogging, false},
+        {Credo.Check.Warning.OperationOnSameValues},
+        {Credo.Check.Warning.OperationWithConstantResult},
+        {Credo.Check.Warning.RaiseInsideRescue},
+        {Credo.Check.Warning.UnusedEnumOperation},
+        {Credo.Check.Warning.UnusedFileOperation},
+        {Credo.Check.Warning.UnusedKeywordOperation},
+        {Credo.Check.Warning.UnusedListOperation},
+        {Credo.Check.Warning.UnusedPathOperation},
+        {Credo.Check.Warning.UnusedRegexOperation},
+        {Credo.Check.Warning.UnusedStringOperation},
+        {Credo.Check.Warning.UnusedTupleOperation}
+      ]
+    }
+  ]
+}

.github/workflows/elixir-ci.yml

@@ -45,12 +45,31 @@ jobs:
       - name: Generate docs
         run: mix docs --warnings-as-errors
 
+  credo-check:
+    name: Check Mix Credo Lint
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+
+      - name: Setup Elixir
+        uses: erlef/setup-elixir@v1
+        with:
+          elixir-version: 1.18
+          otp-version: 28
+
+      - name: Fetch Dependencies
+        run: mix deps.get
+
+      - name: Run Credo Linter
+        run: mix credo --strict --format=flycheck
+
   test:
     name: Run Tests
     runs-on: ubuntu-latest
     needs:
       - format-check
       - docs-check
+      - credo-check
     strategy:
       matrix:
         elixir: [1.18, 1.19]
@@ -79,6 +98,7 @@ jobs:
     needs:
       - format-check
       - docs-check
+      - credo-check
     strategy:
       matrix:
         elixir: [1.15, 1.16, 1.17, 1.18]

lib/cache_decorator.ex

@@ -212,7 +212,7 @@ defmodule CacheDecorator do
       Module.make_overridable(env.module, [{name, length(args_ast)}])
 
       key_template = Keyword.fetch!(opts, :key)
-      key_ast = compile_key_ast!(key_template, args_ast, env.module, name, :cache)
+      key_ast = compile_key_ast!({key_template, args_ast, env.module, name, :cache})
 
       quote do
         def unquote(name)(unquote_splicing(args_ast)) do
@@ -245,7 +245,7 @@ defmodule CacheDecorator do
       Module.make_overridable(env.module, [{name, length(args)}])
 
       raw_key = Keyword.fetch!(opts, :key)
-      key_ast = compile_key_ast!(raw_key, args, env.module, name, :invalidate)
+      key_ast = compile_key_ast!({raw_key, args, env.module, name, :invalidate})
 
       invalidate_ast =
         quote do
@@ -298,8 +298,9 @@ defmodule CacheDecorator do
     List.flatten(patterns_ast ++ [unmatched_pattern_ast])
   end
 
-  defp compile_key_ast!(template, args_ast, env_module, fun_name, decorator_type)
-       when is_binary(template) do
+  defp compile_key_ast!({template, _, _, _, _} = args) when is_binary(template) do
+    {template, args_ast, env_module, fun_name, decorator_type} = args
+
     # Collect *all* bound var names from the function head (deep walk)
     {^args_ast, arg_ast_by_name} =
       Macro.prewalk(args_ast, %{}, fn
@@ -319,15 +320,7 @@ defmodule CacheDecorator do
         # If seg is exactly "{name}", treat it as a variable; otherwise literal.
         case Regex.run(~r/^\{([A-Za-z_][A-Za-z0-9_]*)\}$/u, seg) do
           [_, var] ->
-            case Map.fetch(arg_ast_by_name, var) do
-              {:ok, v_ast} ->
-                quote(do: to_string(unquote(v_ast)))
-
-              :error ->
-                raise ArgumentError,
-                      "#{inspect(__MODULE__)}: unknown variable {#{var}} in :key for " <>
-                        "@#{decorator_type} #{inspect(env_module)}.#{fun_name}/#{length(args_ast)}"
-            end
+            handle_var(var, arg_ast_by_name, args)
 
           nil ->
             quote(do: unquote(seg))
@@ -349,6 +342,20 @@ defmodule CacheDecorator do
     end
   end
 
+  defp handle_var(var, arg_ast_by_name, args) do
+    {_template, args_ast, env_module, fun_name, decorator_type} = args
+
+    case Map.fetch(arg_ast_by_name, var) do
+      {:ok, v_ast} ->
+        quote(do: to_string(unquote(v_ast)))
+
+      :error ->
+        raise ArgumentError,
+              "#{inspect(__MODULE__)}: unknown variable {#{var}} in :key for " <>
+                "@#{decorator_type} #{inspect(env_module)}.#{fun_name}/#{length(args_ast)}"
+    end
+  end
+
   defp invalid_key!(env_module, name, args, key, decorator_type) do
     raise ArgumentError,
           "#{inspect(__MODULE__)}: invalid value #{inspect(key)} in :key " <>

mix.exs

@@ -49,6 +49,7 @@ defmodule CacheDecorator.MixProject do
   defp deps do
     [
       {:cachex, "~> 4.1", only: :test},
+      {:credo, "~> 1.7", only: :dev, runtime: false},
       {:ex_doc, "~> 0.38", only: :dev, runtime: false},
       {:mockery, "~> 2.3", only: :test}
     ]

mix.lock

@@ -1,9 +1,13 @@
 %{
+  "bunt": {:hex, :bunt, "1.0.0", "081c2c665f086849e6d57900292b3a161727ab40431219529f13c4ddcf3e7a44", [:mix], [], "hexpm", "dc5f86aa08a5f6fa6b8096f0735c4e76d54ae5c9fa2c143e5a1fc7c1cd9bb6b5"},
   "cachex": {:hex, :cachex, "4.1.1", "574c5cd28473db313a0a76aac8c945fe44191659538ca6a1e8946ec300b1a19f", [:mix], [{:eternal, "~> 1.2", [hex: :eternal, repo: "hexpm", optional: false]}, {:ex_hash_ring, "~> 6.0", [hex: :ex_hash_ring, repo: "hexpm", optional: false]}, {:jumper, "~> 1.0", [hex: :jumper, repo: "hexpm", optional: false]}, {:sleeplocks, "~> 1.1", [hex: :sleeplocks, repo: "hexpm", optional: false]}, {:unsafe, "~> 1.0", [hex: :unsafe, repo: "hexpm", optional: false]}], "hexpm", "d6b7449ff98d6bb92dda58bd4fc3189cae9f99e7042054d669596f56dc503cd8"},
+  "credo": {:hex, :credo, "1.7.12", "9e3c20463de4b5f3f23721527fcaf16722ec815e70ff6c60b86412c695d426c1", [:mix], [{:bunt, "~> 0.2.1 or ~> 1.0", [hex: :bunt, repo: "hexpm", optional: false]}, {:file_system, "~> 0.2 or ~> 1.0", [hex: :file_system, repo: "hexpm", optional: false]}, {:jason, "~> 1.0", [hex: :jason, repo: "hexpm", optional: false]}], "hexpm", "8493d45c656c5427d9c729235b99d498bd133421f3e0a683e5c1b561471291e5"},
   "earmark_parser": {:hex, :earmark_parser, "1.4.44", "f20830dd6b5c77afe2b063777ddbbff09f9759396500cdbe7523efd58d7a339c", [:mix], [], "hexpm", "4778ac752b4701a5599215f7030989c989ffdc4f6df457c5f36938cc2d2a2750"},
   "eternal": {:hex, :eternal, "1.2.2", "d1641c86368de99375b98d183042dd6c2b234262b8d08dfd72b9eeaafc2a1abd", [:mix], [], "hexpm", "2c9fe32b9c3726703ba5e1d43a1d255a4f3f2d8f8f9bc19f094c7cb1a7a9e782"},
   "ex_doc": {:hex, :ex_doc, "0.38.3", "ddafe36b8e9fe101c093620879f6604f6254861a95133022101c08e75e6c759a", [:mix], [{:earmark_parser, "~> 1.4.44", [hex: :earmark_parser, repo: "hexpm", optional: false]}, {:makeup_c, ">= 0.1.0", [hex: :makeup_c, repo: "hexpm", optional: true]}, {:makeup_elixir, "~> 0.14 or ~> 1.0", [hex: :makeup_elixir, repo: "hexpm", optional: false]}, {:makeup_erlang, "~> 0.1 or ~> 1.0", [hex: :makeup_erlang, repo: "hexpm", optional: false]}, {:makeup_html, ">= 0.1.0", [hex: :makeup_html, repo: "hexpm", optional: true]}], "hexpm", "ecaa785456a67f63b4e7d7f200e8832fa108279e7eb73fd9928e7e66215a01f9"},
   "ex_hash_ring": {:hex, :ex_hash_ring, "6.0.4", "bef9d2d796afbbe25ab5b5a7ed746e06b99c76604f558113c273466d52fa6d6b", [:mix], [], "hexpm", "89adabf31f7d3dfaa36802ce598ce918e9b5b33bae8909ac1a4d052e1e567d18"},
+  "file_system": {:hex, :file_system, "1.1.1", "31864f4685b0148f25bd3fbef2b1228457c0c89024ad67f7a81a3ffbc0bbad3a", [:mix], [], "hexpm", "7a15ff97dfe526aeefb090a7a9d3d03aa907e100e262a0f8f7746b78f8f87a5d"},
+  "jason": {:hex, :jason, "1.4.4", "b9226785a9aa77b6857ca22832cffa5d5011a667207eb2a0ad56adb5db443b8a", [:mix], [{:decimal, "~> 1.0 or ~> 2.0", [hex: :decimal, repo: "hexpm", optional: true]}], "hexpm", "c5eb0cab91f094599f94d55bc63409236a8ec69a21a67814529e8d5f6cc90b3b"},
   "jumper": {:hex, :jumper, "1.0.2", "68cdcd84472a00ac596b4e6459a41b3062d4427cbd4f1e8c8793c5b54f1406a7", [:mix], [], "hexpm", "9b7782409021e01ab3c08270e26f36eb62976a38c1aa64b2eaf6348422f165e1"},
   "makeup": {:hex, :makeup, "1.2.1", "e90ac1c65589ef354378def3ba19d401e739ee7ee06fb47f94c687016e3713d1", [:mix], [{:nimble_parsec, "~> 1.4", [hex: :nimble_parsec, repo: "hexpm", optional: false]}], "hexpm", "d36484867b0bae0fea568d10131197a4c2e47056a6fbe84922bf6ba71c8d17ce"},
   "makeup_elixir": {:hex, :makeup_elixir, "1.0.1", "e928a4f984e795e41e3abd27bfc09f51db16ab8ba1aebdba2b3a575437efafc2", [:mix], [{:makeup, "~> 1.0", [hex: :makeup, repo: "hexpm", optional: false]}, {:nimble_parsec, "~> 1.2.3 or ~> 1.3", [hex: :nimble_parsec, repo: "hexpm", optional: false]}], "hexpm", "7284900d412a3e5cfd97fdaed4f5ed389b8f2b4cb49efc0eb3bd10e2febf9507"},