Merge pull request #1208 from reitermarkus/puts-columns

Refactor `puts_columns` to allow `$stderr.puts_columns`.

1 files changed, 41 insertions, 0 deletions

diff --git a/Library/Homebrew/utils/formatter.rb b/Library/Homebrew/utils/formatter.rb
index cb4f041f4..a29a0d491 100644
--- a/Library/Homebrew/utils/formatter.rb
+++ b/Library/Homebrew/utils/formatter.rb
@@ -49,4 +49,45 @@ module Formatter
     end
   end
   private_class_method :prefix
+
+  def columns(*objects, gap_size: 2)
+    objects = objects.flatten.map(&:to_s)
+
+    fallback = proc do
+      return objects.join("\n").concat("\n")
+    end
+
+    fallback.call if objects.empty?
+    fallback.call if respond_to?(:tty?) ? !tty? : !$stdout.tty?
+
+    console_width = Tty.width
+    object_lengths = objects.map { |obj| Tty.strip_ansi(obj).length }
+    cols = (console_width + gap_size) / (object_lengths.max + gap_size)
+
+    fallback.call if cols < 2
+
+    rows = (objects.count + cols - 1) / cols
+    cols = (objects.count + rows - 1) / rows # avoid empty trailing columns
+
+    col_width = (console_width + gap_size) / cols - gap_size
+
+    gap_string = "".rjust(gap_size)
+
+    output = ""
+
+    rows.times do |row_index|
+      item_indices_for_row = row_index.step(objects.size - 1, rows).to_a
+
+      first_n = item_indices_for_row[0...-1].map { |index|
+        objects[index] + "".rjust(col_width - object_lengths[index])
+      }
+
+      # don't add trailing whitespace to last column
+      last = objects.values_at(item_indices_for_row.last)
+
+      output.concat((first_n + last).join(gap_string)).concat("\n")
+    end
+
+    output
+  end
 end