Add ignore_modules option

README.md

@@ -124,6 +124,12 @@ Optionally, the `ignore_paths` option can be a list of path prefixes to ignore w
     ]
 ```
 
+Optionally, the `ignore_modules` option can be a list of module names as atoms and regular expressions that are matched against the module names to ignore when generating the coverage report.
+
+```elixir
+test_coverage: [tool: LcovEx, output: "cover", ignore_modules: [MyApp.IgnoreModule, ~r/.*Test/]],
+```
+
 ## TODOs
 
 - Add missing `FN` lines, for the sake of completion.

example_project/lib/example_project/example_ignore_module.ex

@@ -0,0 +1,11 @@
+defmodule ExampleProject.ExampleIgnoreModule do
+  @moduledoc false
+
+  def cover() do
+    get_value()
+  end
+
+  defp get_value() do
+    :covered
+  end
+end

example_project/lib/example_project/example_ignore_regex_module.ex

@@ -0,0 +1,11 @@
+defmodule ExampleProject.ExampleIgnoreRegexModule do
+  @moduledoc false
+
+  def cover() do
+    get_value()
+  end
+
+  defp get_value() do
+    :covered
+  end
+end

lib/lcov_ex.ex

@@ -21,15 +21,18 @@ defmodule LcovEx do
 
     output = opts[:output]
     caller_cwd = opts[:cwd] || File.cwd!()
-    ignored_paths = Keyword.get(opts, :ignore_paths, [])
+    ignored_paths = opts[:ignore_paths] || []
+    ignored_modules = opts[:ignore_modules] || []
 
     fn ->
       log_info("\nGenerating lcov file...")
 
       lcov =
         :cover.modules()
         |> Enum.sort()
-        |> Enum.map(&calculate_module_coverage(&1, ignored_paths, caller_cwd))
+        |> Enum.reject(&ignored_module?(&1, ignored_modules))
+        |> Enum.reject(&ignored_path?(&1, ignored_paths, caller_cwd))
+        |> Enum.map(&calculate_module_coverage(&1, caller_cwd))
 
       File.mkdir_p!(output)
       path = "#{output}/lcov.info"
@@ -41,17 +44,24 @@ defmodule LcovEx do
     end
   end
 
-  defp calculate_module_coverage(mod, ignored_paths, cwd) do
+  defp ignored_module?(mod, ignored_modules),
+    do: Enum.any?(ignored_modules, &ignored_any?(mod, &1))
+
+  defp ignored_any?(mod, %Regex{} = re), do: Regex.match?(re, inspect(mod))
+  defp ignored_any?(mod, other), do: mod == other
+
+  # Ignore compiled modules with path:
+  # - not relative to the app (e.g. generated by umbrella dependencies)
+  # - ignored by configuration
+  defp ignored_path?(mod, ignored_paths, cwd) do
     path = mod.module_info(:compile)[:source] |> to_string() |> Path.relative_to(cwd)
 
-    # Ignore compiled modules with path:
-    # - not relative to the app (e.g. generated by umbrella dependencies)
-    # - ignored by configuration
-    if Path.type(path) != :relative or Enum.any?(ignored_paths, &String.starts_with?(path, &1)) do
-      []
-    else
-      calculate_and_format_coverage(mod, path)
-    end
+    Path.type(path) != :relative or Enum.any?(ignored_paths, &String.starts_with?(path, &1))
+  end
+  defp calculate_module_coverage(mod, cwd) do
+    path = mod.module_info(:compile)[:source] |> to_string() |> Path.relative_to(cwd)
+
+    calculate_and_format_coverage(mod, path)
   end
 
   defp calculate_and_format_coverage(mod, path) do

test/lcov_ex_test.exs

@@ -6,7 +6,13 @@ defmodule LcovExTest do
     setup do
       mix_path = "#{File.cwd!()}/example_project/mix.exs" |> String.replace("//", "/")
       MixFileHelper.backup(mix_path)
-      config = [test_coverage: [tool: LcovEx, ignore_paths: ["deps/"]]]
+      config = [
+        test_coverage: [
+          tool: LcovEx,
+          ignore_paths: ["deps/"],
+          ignore_modules: [ExampleProject.ExampleIgnoreModule, ~r/.*ExampleIgnoreRegex.*/]
+        ]
+      ]
       MixFileHelper.update_project_config(mix_path, config)
 
       on_exit(fn ->

test/tasks/lcov_test.exs

@@ -151,6 +151,28 @@ defmodule LcovEx.Tasks.LcovTest do
     LF:1
     LH:1
     end_of_record
+    TN:Elixir.ExampleProject.ExampleIgnoreModule
+    SF:lib/example_project/example_ignore_module.ex
+    FNDA:0,cover/0
+    FNDA:0,get_value/0
+    FNF:2
+    FNH:0
+    DA:5,0
+    DA:8,0
+    LF:2
+    LH:0
+    end_of_record
+    TN:Elixir.ExampleProject.ExampleIgnoreRegexModule
+    SF:lib/example_project/example_ignore_regex_module.ex
+    FNDA:0,cover/0
+    FNDA:0,get_value/0
+    FNF:2
+    FNH:0
+    DA:5,0
+    DA:8,0
+    LF:2
+    LH:0
+    end_of_record
     TN:Elixir.ExampleProject.ExampleModule
     SF:lib/example_project/example_module.ex
     FNDA:1,cover/0