Update test coverage summary to produce a markdown-ish table (#14384)

This allows the table to embedded into places that support Markdown rendering.

Author: maennchen

lib/mix/lib/mix/tasks/test.coverage.ex

@@ -359,11 +359,18 @@ defmodule Mix.Tasks.Test.Coverage do
 
   defp print_summary(results, totals, opts) when is_list(opts) do
     threshold = get_threshold(opts)
-    Mix.shell().info("Percentage | Module")
-    Mix.shell().info("-----------|--------------------------")
-    results |> Enum.sort() |> Enum.each(&display(&1, threshold))
-    Mix.shell().info("-----------|--------------------------")
-    display({totals, "Total"}, threshold)
+
+    results =
+      results |> Enum.sort() |> Enum.map(fn {coverage, module} -> {coverage, inspect(module)} end)
+
+    name_max_length = results |> Enum.map(&String.length(elem(&1, 1))) |> Enum.max() |> max(10)
+    name_separator = String.duplicate("-", name_max_length)
+
+    Mix.shell().info("| Percentage | #{String.pad_trailing("Module", name_max_length)} |")
+    Mix.shell().info("|------------|-#{name_separator}-|")
+    Enum.each(results, &display(&1, threshold, name_max_length))
+    Mix.shell().info("|------------|-#{name_separator}-|")
+    display({totals, "Total"}, threshold, name_max_length)
     Mix.shell().info("")
   end
 
@@ -374,14 +381,16 @@ defmodule Mix.Tasks.Test.Coverage do
     Mix.shell().info("")
   end
 
-  defp display({percentage, name}, threshold) do
+  defp display({percentage, name}, threshold, pad_length) do
     Mix.shell().info([
+      "| ",
       color(percentage, threshold),
       format_number(percentage, 9),
       "%",
       :reset,
       " | ",
-      format_name(name)
+      String.pad_trailing(name, pad_length),
+      " |"
     ])
   end
 
@@ -395,9 +404,6 @@ defmodule Mix.Tasks.Test.Coverage do
 
   defp format_number(number, length), do: :io_lib.format("~#{length}.2f", [number])
 
-  defp format_name(name) when is_binary(name), do: name
-  defp format_name(mod) when is_atom(mod), do: inspect(mod)
-
   defp get_threshold(true), do: @default_threshold
   defp get_threshold(opts), do: Keyword.get(opts, :threshold, @default_threshold)
 end

lib/mix/test/mix/tasks/test_test.exs

@@ -150,12 +150,12 @@ defmodule Mix.Tasks.TestTest do
         assert output =~ """
                Generating cover results ...
 
-               Percentage | Module
-               -----------|--------------------------
-                  100.00% | Bar.Protocol
-                  100.00% | Bar.Protocol.BitString
-               -----------|--------------------------
-                  100.00% | Total
+               | Percentage | Module                 |
+               |------------|------------------------|
+               |    100.00% | Bar.Protocol           |
+               |    100.00% | Bar.Protocol.BitString |
+               |------------|------------------------|
+               |    100.00% | Total                  |
                """
 
         assert output =~ "1 test, 0 failures"
@@ -164,11 +164,11 @@ defmodule Mix.Tasks.TestTest do
         assert output =~ """
                Generating cover results ...
 
-               Percentage | Module
-               -----------|--------------------------
-                  100.00% | Foo
-               -----------|--------------------------
-                  100.00% | Total
+               | Percentage | Module     |
+               |------------|------------|
+               |    100.00% | Foo        |
+               |------------|------------|
+               |    100.00% | Total      |
                """
 
         # We skip a test in bar to force coverage below the default threshold
@@ -195,15 +195,15 @@ defmodule Mix.Tasks.TestTest do
                Importing cover results: apps/bar/cover/default.coverdata
                Importing cover results: apps/foo/cover/default.coverdata
 
-               Percentage | Module
-               -----------|--------------------------
-                  100.00% | Bar
-                  100.00% | Bar.Ignore
-                  100.00% | Bar.Protocol
-                  100.00% | Bar.Protocol.BitString
-                  100.00% | Foo
-               -----------|--------------------------
-                  100.00% | Total
+               | Percentage | Module                 |
+               |------------|------------------------|
+               |    100.00% | Bar                    |
+               |    100.00% | Bar.Ignore             |
+               |    100.00% | Bar.Protocol           |
+               |    100.00% | Bar.Protocol.BitString |
+               |    100.00% | Foo                    |
+               |------------|------------------------|
+               |    100.00% | Total                  |
                """
       end)
     end
@@ -366,12 +366,12 @@ defmodule Mix.Tasks.TestTest do
                Importing cover results: cover/1.coverdata
                Importing cover results: cover/2.coverdata
 
-               Percentage | Module
-               -----------|--------------------------
-                  100.00% | A
-                  100.00% | B
-               -----------|--------------------------
-                  100.00% | Total
+               | Percentage | Module     |
+               |------------|------------|
+               |    100.00% | A          |
+               |    100.00% | B          |
+               |------------|------------|
+               |    100.00% | Total      |
 
                Generated HTML coverage results in \"cover\" directory
                """