martosaur · martosaur · Apr 30, 2025 · Apr 30, 2025
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
@@ -0,0 +1,60 @@
+name: CI
+
+on:
+  pull_request:
+  push:
+    branches:
+      - main
+
+jobs:
+  test:
+    runs-on: ubuntu-24.04
+    env:
+      MIX_ENV: test
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - pair:
+              elixir: "1.15.7"
+              otp: "24.3.4.17"
+          - pair:
+              elixir: "1.16.3"
+              otp: "25.3.2.20"
+          - pair:
+              elixir: "1.17.3"
+              otp: "26.2.5.11"
+          - pair:
+              elixir: "1.18.3"
+              otp: "27.3.3"
+            lint: lint
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: erlef/setup-beam@v1
+        with:
+          otp-version: ${{matrix.pair.otp}}
+          elixir-version: ${{matrix.pair.elixir}}
+          version-type: strict
+
+      - uses: actions/cache@v4
+        with:
+          path: |
+            deps
+            _build
+          key: ${{ runner.os }}-mix-${{matrix.pair.elixir}}-${{matrix.pair.otp}}-${{ hashFiles('**/mix.lock') }}
+
+      - run: mix deps.get --check-locked
+
+      - run: mix format --check-formatted
+        if: ${{ matrix.lint }}
+
+      - run: mix deps.unlock --check-unused
+        if: ${{ matrix.lint }}
+
+      - run: mix deps.compile
+
+      - run: mix compile --no-optional-deps --warnings-as-errors
+        if: ${{ matrix.lint }}
+
+      - run: mix test
diff --git a/lib/logger_handler_kit/act.ex b/lib/logger_handler_kit/act.ex
@@ -47,7 +47,7 @@ defmodule LoggerHandlerKit.Act do
   default, but a thorough handler might have an interest in them.
   """
 
-  require ExUnit.Assertions
+  import ExUnit.Assertions
 
   @doc """
   The most basic and perhaps most common log message is a simple [string](`String`) passed to one of the `Logger` functions:
@@ -569,19 +569,28 @@ defmodule LoggerHandlerKit.Act do
     :exit, {{%RuntimeError{message: "oops"}, _}, _} -> :ok
   end
 
-  def genserver_crash(:process_label) do
-    {:ok, pid} = LoggerHandlerKit.GenServer.start(nil)
-
-    GenServer.call(
-      pid,
-      {:run,
-       fn ->
-         Process.set_label({:any, "term"})
-         raise "oops"
-       end}
-    )
-  catch
-    :exit, {{%RuntimeError{message: "oops"}, _}, _} -> :ok
+  if System.otp_release() < "27" do
+    def genserver_crash(:process_label),
+      do:
+        raise("""
+        Process labels were introduced in OTP 27.
+        If you want to run test suite for older Elixir version, considder skipping the test with `@tag skip: System.otp_release() < "27"`
+        """)
+  else
+    def genserver_crash(:process_label) do
+      {:ok, pid} = LoggerHandlerKit.GenServer.start(nil)
+
+      GenServer.call(
+        pid,
+        {:run,
+         fn ->
+           Process.set_label({:any, "term"})
+           raise "oops"
+         end}
+      )
+    catch
+      :exit, {{%RuntimeError{message: "oops"}, _}, _} -> :ok
+    end
   end
 
   def genserver_crash(:named_client) do
@@ -608,7 +617,7 @@ defmodule LoggerHandlerKit.Act do
           {:run,
            fn {caller, _}, _ ->
              caller_monitor = Process.monitor(caller)
-             ExUnit.Assertions.assert_receive({:DOWN, ^caller_monitor, _, _, _})
+             assert_receive({:DOWN, ^caller_monitor, _, _, _})
              raise "oops"
            end},
           0
@@ -618,15 +627,15 @@ defmodule LoggerHandlerKit.Act do
       end
     end)
 
-    ExUnit.Assertions.assert_receive({:DOWN, ^mon, _, _, _})
+    assert_receive({:DOWN, ^mon, _, _, _})
     :ok
   end
 
   def genserver_crash(:no_client) do
     {:ok, pid} = LoggerHandlerKit.GenServer.start(nil)
     mon = Process.monitor(pid)
     GenServer.cast(pid, fn -> raise "oops" end)
-    ExUnit.Assertions.assert_receive({:DOWN, ^mon, _, _, _})
+    assert_receive({:DOWN, ^mon, _, _, _})
     :ok
   end
 
@@ -754,28 +763,28 @@ defmodule LoggerHandlerKit.Act do
   def task_error(:exception) do
     {:ok, pid} = Task.start(fn -> raise "oops" end)
     ref = Process.monitor(pid)
-    ExUnit.Assertions.assert_receive({:DOWN, ^ref, _, _, _})
+    assert_receive({:DOWN, ^ref, _, _, _})
     :ok
   end
 
   def task_error(:exit) do
     {:ok, pid} = Task.start(fn -> exit("i quit") end)
     ref = Process.monitor(pid)
-    ExUnit.Assertions.assert_receive({:DOWN, ^ref, _, _, _})
+    assert_receive({:DOWN, ^ref, _, _, _})
     :ok
   end
 
   def task_error(:throw) do
     {:ok, pid} = Task.start(fn -> throw("catch!") end)
     ref = Process.monitor(pid)
-    ExUnit.Assertions.assert_receive({:DOWN, ^ref, _, _, _})
+    assert_receive({:DOWN, ^ref, _, _, _})
     :ok
   end
 
   def task_error(:undefined) do
     {:ok, pid} = Task.start(:module_does_not_exist, :undef, [])
     ref = Process.monitor(pid)
-    ExUnit.Assertions.assert_receive({:DOWN, ^ref, _, _, _})
+    assert_receive({:DOWN, ^ref, _, _, _})
     :ok
   end
 
@@ -1046,7 +1055,7 @@ defmodule LoggerHandlerKit.Act do
 
     LoggerHandlerKit.Arrange.allow(self(), pid, handler_id)
     send(pid, :go)
-    ExUnit.Assertions.assert_receive({:DOWN, ^ref, _, _, _})
+    assert_receive({:DOWN, ^ref, _, _, _})
     :ok
   end
 
@@ -1062,7 +1071,7 @@ defmodule LoggerHandlerKit.Act do
 
     LoggerHandlerKit.Arrange.allow(self(), pid, handler_id)
     send(pid, :go)
-    ExUnit.Assertions.assert_receive({:DOWN, ^ref, _, _, _})
+    assert_receive({:DOWN, ^ref, _, _, _})
     :ok
   end
 
@@ -1428,7 +1437,7 @@ defmodule LoggerHandlerKit.Act do
 
     ref = Process.monitor(pid)
 
-    ExUnit.Assertions.assert_receive({:DOWN, ^ref, _, _, _})
+    assert_receive({:DOWN, ^ref, _, _, _})
     :ok
   end
 
@@ -1443,7 +1452,7 @@ defmodule LoggerHandlerKit.Act do
 
     ref = Process.monitor(pid)
 
-    ExUnit.Assertions.assert_receive({:DOWN, ^ref, _, _, _})
+    assert_receive({:DOWN, ^ref, _, _, _})
     :ok
   end
 
@@ -1458,7 +1467,7 @@ defmodule LoggerHandlerKit.Act do
 
     ref = Process.monitor(pid)
 
-    ExUnit.Assertions.assert_receive({:DOWN, ^ref, _, _, _})
+    assert_receive({:DOWN, ^ref, _, _, _})
     :ok
   end
 
@@ -1591,7 +1600,7 @@ defmodule LoggerHandlerKit.Act do
     })
 
     Process.exit(pid, :normal)
-    ExUnit.Assertions.assert_receive({:DOWN, ^ref, _, _, _})
+    assert_receive({:DOWN, ^ref, _, _, _})
     :ok
   end
 
@@ -1650,7 +1659,7 @@ defmodule LoggerHandlerKit.Act do
        exit(:stop)
      end})
 
-    ExUnit.Assertions.assert_receive({:EXIT, ^pid, _})
+    assert_receive({:EXIT, ^pid, _})
     :ok
   end
 end
diff --git a/lib/logger_handler_kit/handler_wrapper.ex b/lib/logger_handler_kit/handler_wrapper.ex
@@ -47,9 +47,17 @@ defmodule LoggerHandlerKit.HandlerWrapper do
   ```
   """
 
-  @behaviour :logger_handler
+  # Prior to OTP 27 :logger_handler behaviour didn't exist and callbacks were part of :logger.
+  # https://github.com/erlang/otp/commit/2afd6748f16ad226d0ae12b54e57e0147dafdbdd
+  if System.otp_release() < "27" do
+    @behaviour_module false
+  else
+    @behaviour_module :logger_handler
+    @behaviour @behaviour_module
+  end
+
+  if @behaviour_module, do: @impl(@behaviour_module)
 
-  @impl :logger_handler
   def adding_handler(config) do
     unwrapped = unwrap_config(config)
     Code.ensure_loaded!(unwrapped.module)
@@ -62,7 +70,8 @@ defmodule LoggerHandlerKit.HandlerWrapper do
     end
   end
 
-  @impl :logger_handler
+  if @behaviour_module, do: @impl(@behaviour_module)
+
   def log(log_event, %{config: %{test_pid: test_pid, ref: ref}} = config) do
     config
     |> unwrap_config()
@@ -74,7 +83,8 @@ defmodule LoggerHandlerKit.HandlerWrapper do
     _ -> send(test_pid, {ref, :log_call_completed})
   end
 
-  @impl :logger_handler
+  if @behaviour_module, do: @impl(@behaviour_module)
+
   def removing_handler(config) do
     unwrapped = unwrap_config(config)
 
@@ -83,7 +93,8 @@ defmodule LoggerHandlerKit.HandlerWrapper do
     end
   end
 
-  @impl :logger_handler
+  if @behaviour_module, do: @impl(@behaviour_module)
+
   def changing_config(set_or_update, old_config, new_config) do
     old_unwrapped = unwrap_config(old_config)
     new_unwrapped = unwrap_config(new_config)

diff --git a/mix.exs b/mix.exs
@@ -8,7 +8,7 @@ defmodule LoggerHandlerKit.MixProject do
     [
       app: :logger_handler_kit,
       version: @version,
-      elixir: "~> 1.18",
+      elixir: "~> 1.15",
       elixirc_paths: elixirc_paths(Mix.env()),
       start_permanent: Mix.env() == :prod,
       deps: deps(),

diff --git a/test/default_logger_test.exs b/test/default_logger_test.exs
@@ -151,6 +151,7 @@ defmodule LoggerHandlerKit.DefaultLoggerTest do
       assert msg =~ "[error] GenServer \"genserver global name\""
     end
 
+    @tag skip: System.otp_release() < "27"
     test "genserver crash with process label", %{handler_ref: ref, io_ref: io_ref} do
       LoggerHandlerKit.Act.genserver_crash(:process_label)
       LoggerHandlerKit.Assert.assert_logged(ref)
@@ -226,6 +227,9 @@ defmodule LoggerHandlerKit.DefaultLoggerTest do
                "(UndefinedFunctionError) function :module_does_not_exist.undef/0 is undefined"
     end
 
+    # Before Elixir 1.17 gen_statem crashes were swallowed by Logger.Translator
+    # https://github.com/elixir-lang/elixir/pull/13451
+    @tag skip: System.version() < "1.17"
     test "gen_statem crash exception", %{handler_ref: ref, io_ref: io_ref} do
       LoggerHandlerKit.Act.gen_statem_crash(:exception)
       LoggerHandlerKit.Assert.assert_logged(ref)
@@ -235,6 +239,7 @@ defmodule LoggerHandlerKit.DefaultLoggerTest do
       assert msg =~ "** (RuntimeError) oops"
     end
 
+    @tag skip: System.version() < "1.17"
     test "gen_statem crash exit", %{handler_ref: ref, io_ref: io_ref} do
       LoggerHandlerKit.Act.gen_statem_crash(:exit)
       LoggerHandlerKit.Assert.assert_logged(ref)
@@ -244,6 +249,7 @@ defmodule LoggerHandlerKit.DefaultLoggerTest do
       assert msg =~ "** (stop) \"i quit\""
     end
 
+    @tag skip: System.version() < "1.17"
     test "gen_statem crash throw", %{handler_ref: ref, io_ref: io_ref} do
       LoggerHandlerKit.Act.gen_statem_crash(:throw)
       LoggerHandlerKit.Assert.assert_logged(ref)
@@ -327,7 +333,13 @@ defmodule LoggerHandlerKit.DefaultLoggerTest do
       LoggerHandlerKit.Assert.assert_logged(ref)
 
       assert_receive {^io_ref, msg}
-      assert msg =~ "[debug] Child :task of Supervisor #PID<"
+
+      if System.otp_release() < "27" do
+        assert msg =~ "[info] Child :task of Supervisor #PID<"
+      else
+        assert msg =~ "[debug] Child :task of Supervisor #PID<"
+      end
+
       assert msg =~ " (Supervisor.Default) started"
     end