Sample Credo file

.credo.exs

%{
  configs: [
    %{
      name: "default",
      files: %{
        included: ["lib/", "src/", "web/", "test/"],
        excluded: []
      },
      checks: [
        {Credo.Check.Consistency.ExceptionNames},
        {Credo.Check.Consistency.LineEndings},
        {Credo.Check.Consistency.SpaceAroundOperators},
        {Credo.Check.Consistency.SpaceInParentheses},
        {Credo.Check.Consistency.TabsOrSpaces},

        # For some checks, like AliasUsage, you can only customize the priority
        # Priority values are: `low, normal, high, higher`
        {Credo.Check.Readability.FunctionNames},
        {Credo.Check.Readability.ModuleAttributeNames},
        {Credo.Check.Readability.ModuleDoc},
        {Credo.Check.Readability.ModuleNames},
        {Credo.Check.Readability.PredicateFunctionNames},
        {Credo.Check.Readability.TrailingBlankLine},
        {Credo.Check.Readability.TrailingWhiteSpace},
        {Credo.Check.Readability.VariableNames},

        {Credo.Check.Refactor.ABCSize, max_size: 40},
        {Credo.Check.Refactor.CaseTrivialMatches},
        {Credo.Check.Refactor.CondStatements},
        {Credo.Check.Refactor.FunctionArity, max_arity: 5},
        {Credo.Check.Refactor.MatchInCondition},
        {Credo.Check.Refactor.CyclomaticComplexity},
        {Credo.Check.Refactor.PipeChainStart, false},
        {Credo.Check.Design.AliasUsage, false},
        {Credo.Check.Refactor.NegatedConditionsInUnless},
        {Credo.Check.Refactor.NegatedConditionsWithElse},
        {Credo.Check.Refactor.Nesting, max_nesting: 3},
        {Credo.Check.Refactor.UnlessWithElse},

        {Credo.Check.Warning.IExPry},
        {Credo.Check.Warning.IoInspect},
        {Credo.Check.Warning.NameRedeclarationByAssignment},
        {Credo.Check.Warning.NameRedeclarationByCase},
        {Credo.Check.Warning.NameRedeclarationByDef},
        {Credo.Check.Warning.NameRedeclarationByFn},
        {Credo.Check.Warning.OperationOnSameValues},
        {Credo.Check.Warning.UnusedEnumOperation},
        {Credo.Check.Warning.UnusedKeywordOperation},
        {Credo.Check.Warning.UnusedListOperation},
        {Credo.Check.Warning.UnusedStringOperation},
        {Credo.Check.Warning.UnusedTupleOperation},
        {Credo.Check.Warning.OperationWithConstantResult},


        {Credo.Check.Readability.MaxLineLength, priority: :low, max_length: 3000},
        {Credo.Check.Design.DuplicatedCode, mass_threshold: 16, nodes_threshold: 2},

        # You can also customize the exit_status of each check.
        # If you don't want TODO comments to cause `mix credo` to fail, just
        # set this value to 0 (zero).
        {Credo.Check.Design.TagTODO, exit_status: 0},
      ]
    }
  ]
}