feat: Report coverage to gitlab

.gitignore

@@ -44,3 +44,6 @@ config/*.secret.exs
 
 # Temporary CI build file
 build.env
+
+# CI metrics file
+metrics.txt

.gitlab-ci.yml

@@ -26,7 +26,7 @@ variables:
   - name: postgres:12
   script: script/cibuild
 
-test:
+test_1.10.4:
   <<: *test_template
   image: "elixir:1.10.4-alpine"
 
@@ -34,9 +34,17 @@ test_1.11.4:
   <<: *test_template
   image: "elixir:1.11.4-alpine"
 
-test_1.12.1:
+test:
   <<: *test_template
   image: "elixir:1.12.1-alpine"
+  script:
+    - script/cibuild
+    - script/coverage-json-to-metrics
+    - script/coverage-json-to-cobertura
+  artifacts:
+    reports:
+      metrics: metrics.txt
+      cobertura: cover/cobertura.xml
 
 credo:
   stage: test

mix.exs

@@ -13,7 +13,14 @@ defmodule Legendary.Mixfile do
       deps: deps(),
       test_coverage: [tool: ExCoveralls],
       aliases: aliases(),
-      preferred_cli_env: [coveralls: :test, "coveralls.detail": :test, "coveralls.post": :test, "coveralls.html": :test, "coveralls.json": :test],
+      preferred_cli_env: [
+        coveralls: :test,
+        "coveralls.detail": :test,
+        "coveralls.post": :test,
+        "coveralls.html": :test,
+        "coveralls.json": :test,
+        "coveralls.xml": :test
+      ],
     ]
   end
 

script/cibuild

@@ -12,6 +12,6 @@ mix deps.get
 mix ecto.create
 mix ecto.migrate
 
-mix test
+mix coveralls.json
 
 script/restore-timestamps

script/coverage-json-to-cobertura

@@ -0,0 +1,105 @@
+#!/usr/bin/env elixir
+
+Mix.install([
+  {:jason, "~> 1.0"},
+  {:xml_builder, "~> 2.1"}
+])
+
+%{"source_files" => data} =
+  "cover/excoveralls.json"
+  |> File.read!()
+  |> Jason.decode!()
+
+{total_covered, total_total} =
+  data
+  |> Enum.reduce({0,0}, fn %{"coverage" => cover}, {covered, total} ->
+    file_covered =
+      cover
+      |> Enum.reduce(0, &(if is_integer(&1) && &1 > 0, do: &2 + 1, else: &2))
+
+    file_total =
+      cover
+      |> Enum.reduce(0, &(if is_nil(&1), do: &2, else: &2 + 1))
+
+    {covered + file_covered, total + file_total}
+  end)
+
+ratio = total_covered / total_total
+
+files =
+  data
+  |> Enum.map(fn %{"coverage" => cover, "name" => name} ->
+    file_covered =
+      cover
+      |> Enum.reduce(0, &(if is_integer(&1) && &1 > 0, do: &2 + 1, else: &2))
+
+    file_total =
+      cover
+      |> Enum.reduce(0, &(if is_nil(&1), do: &2, else: &2 + 1))
+
+    lines =
+      cover
+      |> Enum.with_index
+      |> Enum.map(fn
+        {nil, _index} ->
+          nil
+        {line, index} ->
+          {:line, %{"number" => index, "hits" => line}, []}
+      end)
+      |> Enum.reject(&is_nil/1)
+
+    ratio =
+      if file_total == 0 do
+        1.0
+      else
+        file_covered / file_total
+      end
+
+    {
+      :class,
+      %{"filename" => name, "line-rate" => ratio},
+      [
+        {
+          :lines,
+          %{},
+          lines
+        }
+      ]
+    }
+  end)
+
+buffer =
+  XmlBuilder.document([
+    XmlBuilder.doctype(
+      "coverage",
+      system: ["http://cobertura.sourceforge.net/xml/coverage-03.dtd"]
+    ),
+    {
+      :coverage,
+      %{
+        "line-rate" => ratio,
+      },
+      [
+        {
+          :packages,
+          %{},
+          [
+            {
+              :package,
+              %{"name" => "", "line-rate" => ratio},
+              [
+                {
+                  :classes,
+                  %{},
+                  files
+                }
+              ]
+            }
+          ]
+        }
+      ]
+    }
+  ])
+  |> XmlBuilder.generate
+
+File.write!("cover/cobertura.xml", buffer)

script/coverage-json-to-metrics

@@ -0,0 +1,30 @@
+#!/usr/bin/env elixir
+
+Mix.install([
+  {:jason, "~> 1.0"}
+])
+
+%{"source_files" => data} =
+  "cover/excoveralls.json"
+  |> File.read!()
+  |> Jason.decode!()
+
+{total_covered, total_total} =
+  data
+  |> Enum.reduce({0,0}, fn %{"coverage" => cover}, {covered, total} ->
+    file_covered =
+      cover
+      |> Enum.reduce(0, &(if is_integer(&1) && &1 > 0, do: &2 + 1, else: &2))
+
+    file_total =
+      cover
+      |> Enum.reduce(0, &(if is_nil(&1), do: &2, else: &2 + 1))
+
+    {covered + file_covered, total + file_total}
+  end)
+
+ratio =
+  (total_covered / total_total)
+  |> Float.round(3)
+
+File.write!("metrics.txt", "coverage #{ratio}")