From 79dd7e32c246071bdeef7362c1bf4d1ddf45d881 Mon Sep 17 00:00:00 2001
From: Tobias Pfeiffer <pragtob@gmail.com>
Date: Fri, 22 Dec 2023 09:30:53 +0100
Subject: [PATCH] find and fix particularly nasty bug that lead to real bad
 output always appending 0 ns

---
 lib/benchee/conversion/duration.ex        | 3 +++
 lib/benchee/conversion/format.ex          | 5 +++++
 test/benchee/conversion/duration_test.exs | 5 +++++
 3 files changed, 13 insertions(+)

diff --git a/lib/benchee/conversion/duration.ex b/lib/benchee/conversion/duration.ex
index 45d58895..a935654c 100644
--- a/lib/benchee/conversion/duration.ex
+++ b/lib/benchee/conversion/duration.ex
@@ -288,6 +288,9 @@ defmodule Benchee.Conversion.Duration do
 
       iex> format_human(0)
       "0 ns"
+
+      iex> format_human(2 * 1000 * 1000 * 1000)
+      "2 s"
   """
   def format_human(duration) do
     Format.format_human(duration, __MODULE__)
diff --git a/lib/benchee/conversion/format.ex b/lib/benchee/conversion/format.ex
index acf1c6bb..da3776b1 100644
--- a/lib/benchee/conversion/format.ex
+++ b/lib/benchee/conversion/format.ex
@@ -85,6 +85,10 @@ defmodule Benchee.Conversion.Format do
     format(0, module)
   end
 
+  def format_human(+0.0, module) do
+    format(0, module)
+  end
+
   def format_human(number, module) when is_number(number) do
     number
     |> split_into_place_values(module)
@@ -108,6 +112,7 @@ defmodule Benchee.Conversion.Format do
 
   @spec place_values(number, [Unit.t()]) :: [{number, Unit.t()}]
   defp place_values(0, _units), do: []
+  defp place_values(+0.0, _units), do: []
 
   # smalles unit, carries the decimal
   defp place_values(number, [base_unit = %Unit{magnitude: 1}]), do: [{number, base_unit}]
diff --git a/test/benchee/conversion/duration_test.exs b/test/benchee/conversion/duration_test.exs
index 3592f448..1d33f8b4 100644
--- a/test/benchee/conversion/duration_test.exs
+++ b/test/benchee/conversion/duration_test.exs
@@ -74,6 +74,11 @@ defmodule Benchee.Conversion.DurationTest do
       assert format_human(9_008) == "9 μs 8 ns"
     end
 
+    # particularly nasty bug
+    test ".format_human()" do
+      assert format_human(2_000_000_000.0) == "2 s"
+    end
+
     test ".format_human(9_876.54321)" do
       assert format_human(9_876.54321) == "9 μs 876.54 ns"
     end