make credo happy

.credo.exs

@@ -31,6 +31,7 @@
         {Credo.Check.Readability.PredicateFunctionNames},
         {Credo.Check.Readability.TrailingBlankLine},
         {Credo.Check.Readability.TrailingWhiteSpace},
+        {Credo.Check.Readability.ParenthesesOnZeroArityDefs, false},
         {Credo.Check.Readability.VariableNames},
 
         {Credo.Check.Refactor.ABCSize},
@@ -41,7 +42,7 @@
         {Credo.Check.Refactor.CyclomaticComplexity},
         {Credo.Check.Refactor.NegatedConditionsInUnless},
         {Credo.Check.Refactor.NegatedConditionsWithElse},
-        {Credo.Check.Refactor.Nesting},
+        {Credo.Check.Refactor.Nesting, max_nesting: 3},
         {Credo.Check.Refactor.UnlessWithElse},
 
         {Credo.Check.Warning.IExPry},

lib/prometheus.ex

@@ -42,7 +42,6 @@ defmodule Prometheus do
    - [Phoenix Instrumenter](https://hex.pm/packages/prometheus_phoenix);
    - [RabbitMQ Exporter](https://github.com/deadtrickster/prometheus_rabbitmq_exporter).
 
-
   ## Erlang VM Collectors
    - [Memory Collector](vm-memory-collector.html);
    - [Statistics Collector](vm-statistics-collector.html);
@@ -103,7 +102,6 @@ defmodule Prometheus do
    - `Prometheus.Model` - provides API for working with underlying Prometheus models.
    You'll use that if you want to create custom collector.
 
-
   """
 
   defmacro __using__(_opts) do

lib/prometheus/config.ex

@@ -59,13 +59,12 @@ defmodule Prometheus.Config do
         end
 
         defp config(key, option) do
-          try do
-            key
-            |> config()
-            |> Keyword.fetch!(option)
-          rescue
-            e in KeyError -> raise %KeyNotFoundError{key: key, option: option}
-          end
+          key
+          |> config()
+          |> Keyword.fetch!(option)
+        rescue
+          # credo:disable-for-next-line Credo.Check.Warning.RaiseInsideRescue
+          e in KeyError -> raise %KeyNotFoundError{key: key, option: option}
         end
 
         unquote do

lib/prometheus/erlang.ex

@@ -76,7 +76,7 @@ defmodule Prometheus.Erlang do
   defp parse_metric_call_args(mf_or_spec, spec, arguments) do
     case mf_or_spec do
       ## Erlang.metric_call({:prometheus_counter, :dinc}, spec, [value])
-      {_,_} -> {mf_or_spec, spec, arguments}
+      {_, _} -> {mf_or_spec, spec, arguments}
       ## Erlang.metric_call(:inc, spec, [value])
       _ when is_atom(mf_or_spec) -> {mf_or_spec, spec, arguments}
       _ ->
@@ -108,7 +108,7 @@ defmodule Prometheus.Erlang do
                            _ when is_list(mf) ->
                              {f, _arity} = __CALLER__.function
                              {Module.get_attribute(__CALLER__.module, :erlang_module), f}
-                           {_,_} ->
+                           {_, _} ->
                              mf
                            _ when is_atom(mf) ->
                              {Module.get_attribute(__CALLER__.module, :erlang_module), mf}

lib/prometheus/error.ex

@@ -59,7 +59,6 @@ end
 defmodule Prometheus.UnknownMetricError do
   defexception [:registry, :name]
 
-
   def message(%{registry: registry, name: name}) do
     "Unknown metric {registry: #{registry}, name: #{name}}."
   end
@@ -155,8 +154,8 @@ end
 defmodule Prometheus.Error do
   @moduledoc false
 
-  @lint [{Credo.Check.Refactor.ABCSize, false},
-         {Credo.Check.Refactor.CyclomaticComplexity, false}]
+  # credo:disable-for-this-file Credo.Check.Refactor.ABCSize
+  # credo:disable-for-this-file Credo.Check.Refactor.CyclomaticComplexity
   def normalize(erlang_error) do
     case erlang_error do
       %ErlangError{original: original} ->

lib/prometheus/metric.ex

@@ -30,14 +30,17 @@ defmodule Prometheus.Metric do
     module_name = __CALLER__.module
 
     quote do
+      # credo:disable-for-next-line Credo.Check.Readability.SpaceAfterCommas
       alias Prometheus.Metric.{Counter,Gauge,Histogram,Summary,Boolean}
+      # credo:disable-for-next-line Credo.Check.Readability.SpaceAfterCommas
       require Prometheus.Metric.{Counter,Gauge,Histogram,Summary,Boolean}
       require Prometheus.Error
 
       unquote_splicing(
         for metric <- @metrics do
           quote do
-            Module.register_attribute unquote(module_name), unquote(metric), accumulate: true
+            Module.register_attribute(unquote(module_name), unquote(metric),
+              accumulate: true)
           end
         end)
 
@@ -66,24 +69,27 @@ defmodule Prometheus.Metric do
         end
       end
 
-      unquote(
-        case get_on_load_attribute(env.module) do
-          nil ->
-            quote do
-              @on_load :__declare_prometheus_metrics__
-            end
-          on_load ->
-            Module.delete_attribute(env.module, :on_load)
-            Module.put_attribute(env.module, :on_load, :__prometheus_on_load_override__)
-            quote do
-              def __prometheus_on_load_override__() do
-                case unquote(on_load)() do
-                  :ok -> __declare_prometheus_metrics__()
-                  result -> result
-                end
-              end
+      unquote(gen_on_load(env))
+    end
+  end
+
+  defp gen_on_load(env) do
+    case get_on_load_attribute(env.module) do
+      nil ->
+        quote do
+          @on_load :__declare_prometheus_metrics__
+        end
+      on_load ->
+        Module.delete_attribute(env.module, :on_load)
+        Module.put_attribute(env.module, :on_load, :__prometheus_on_load_override__)
+        quote do
+          def __prometheus_on_load_override__() do
+            case unquote(on_load)() do
+              :ok -> __declare_prometheus_metrics__()
+              result -> result
             end
-        end)
+          end
+        end
     end
   end
 

test/contrib/mnesia_test.exs

@@ -24,13 +24,11 @@ defmodule Prometheus.Contrib.MnesiaTest do
   end
 
   defp set_custom_mnesia_dir(dir) do
-    try do
-      :ets.lookup_element(:mnesia_gvar, :dir, 2)
-      :ets.update_element(:mnesia_gvar, :dir, dir)
-    rescue
-      ArgumentError ->
-        :application.set_env(:mnesia, :dir, dir)
-    end
+    :ets.lookup_element(:mnesia_gvar, :dir, 2)
+    :ets.update_element(:mnesia_gvar, :dir, dir)
+  rescue
+    ArgumentError ->
+      :application.set_env(:mnesia, :dir, dir)
   end
 
 end

test/format/protobuf_test.exs

@@ -1,3 +1,4 @@
+# credo:disable-for-this-file Credo.Check.Readability.SpaceAfterCommas
 defmodule Prometheus.Format.ProtobufTest do
   use Prometheus.Case
 

test/injector_test.exs

@@ -128,7 +128,7 @@ defmodule Prometheus.InjectorTest do
       QweInjector.inject_ do
         IO.puts("Doing dangerous work #{x}")
       rescue
-        _-> IO.puts("Died")
+        _ -> IO.puts("Died")
       after
         IO.puts("Done anyway")
       end

test/metric/counter_test.exs

@@ -244,12 +244,12 @@ defmodule Prometheus.CounterTest do
     Counter.count_no_exceptions [name: :no_exceptions_total] do
       Counter.count_exceptions [name: :exceptions_total], ArithmeticError do
         def sometimes_raise(arg) do
-          5/arg
+          5 / arg
         end
       end
 
       def sometimes_raise1(arg) when is_list(arg) do
-          5/arg
+        5 / arg
       end
     end
 
@@ -262,7 +262,7 @@ defmodule Prometheus.CounterTest do
 
     Counter.count_exceptions [name: :exceptions_total] do
       def sometimes_raise_any(arg) do
-        5/arg
+        5 / arg
       end
     end
   end

test/metric/gauge_test.exs

@@ -302,7 +302,7 @@ defmodule Prometheus.GaugeTest do
 
     Gauge.dec(spec)
     Gauge.dec(spec, 3)
-    assert -4 == Gauge.value(spec)
+    assert (-4 == Gauge.value(spec))
 
     Gauge.reset(spec)
 
@@ -319,7 +319,7 @@ defmodule Prometheus.GaugeTest do
 
     ## ddec is async. let's make sure gen_server processed our request
     Process.sleep(10)
-    assert -4.5 == Gauge.value(spec)
+    assert (-4.5 == Gauge.value(spec))
 
     Gauge.reset(spec)
 
@@ -364,7 +364,6 @@ defmodule Prometheus.GaugeTest do
 
     assert 1 == Gauge.track_inprogress(spec, do: Gauge.value(spec))
 
-
     assert_raise ErlangError, fn ->
       Gauge.track_inprogress spec do
         :erlang.error({:qwe})

test/metric_test.exs

@@ -62,7 +62,9 @@ defmodule Prometheus.MetricTest do
     assert false == Summary.declare(name: :test_summary1, labels: [], help: "qwe")
     assert false == Summary.declare(name: :test_summary2, labels: [:tag], help: "qwa")
 
-    assert false == Histogram.declare(name: :test_histogram1, labels: [], buckets: [1, 2], help: "qwe")
-    assert false == Histogram.declare(name: :test_histogram2, labels: [:tag], buckets: [1, 2], help: "qwa")
+    assert false ==
+      Histogram.declare(name: :test_histogram1, labels: [], buckets: [1, 2], help: "")
+    assert false ==
+      Histogram.declare(name: :test_histogram2, labels: [:tag], buckets: [1, 2], help: "")
   end
 end

test/model_test.exs

@@ -11,10 +11,10 @@ defmodule Prometheus.ModelTest do
   end
 
   test "create_mf" do
-    assert {:MetricFamily,<<"pool_size">>,<<"help">>,:UNTYPED,
-            [{:Metric,[],:undefined,:undefined,:undefined,
-              {:Untyped,365},
-              :undefined,:undefined}]} ==
+    assert {:MetricFamily, <<"pool_size">>, <<"help">>, :UNTYPED,
+            [{:Metric, [], :undefined, :undefined, :undefined,
+              {:Untyped, 365},
+              :undefined, :undefined}]} ==
       Prometheus.Model.create_mf(
         :pool_size, "help", :untyped, Prometheus.ModelTest, :undefined)
   end