Shared multitask prerequisite intermittently executed multiple times

Given a Rakefile

multitask :default => [:a, :b, :c, :d, :e]

task :a => ['target']
task :b => ['target']
task :c => ['target']
task :d => ['target']
task :e => ['target']

rule(/^target$/ => [ 'source' ]) do |t|
    p "#{t.name} => #{t.source}"
    p t.actions
end

file 'source'

the target may get executed multiple times like this

$ ruby --version
ruby 2.5.1p57 (2018-03-29 revision 63029) [x86_64-linux-musl]
$ rake --version
rake, version 12.3.1
$ rake --trace --rules
** Invoke default (first_time)
** Invoke a (first_time)
Attempting Rule target => source
** Invoke b (first_time)
Attempting Rule target => source
** Invoke c (first_time)
Attempting Rule target => source
** Invoke d (first_time)
Attempting Rule target => source
(target => source ... EXIST)
** Invoke e (first_time)
Attempting Rule target => source
(target => source ... EXIST)
(target => source ... EXIST)
** Invoke target (first_time)
(target => source ... EXIST)
** Invoke source (first_time)
(target => source ... EXIST)
** Execute source
** Execute target
"target => source"
[#<Proc:0x000055e092b971c0@/repo/Rakefile:10>, #<Proc:0x000055e092b971c0@/repo/Rakefile:10>, #<Proc:0x000055e092b971c0@/repo/Rakefile:10>, #<Proc:0x000055e092b971c0@/repo/Rakefile:10>, #<Proc:0x000055e092b971c0@/repo/Rakefile:10>]
"target => source"
[#<Proc:0x000055e092b971c0@/repo/Rakefile:10>, #<Proc:0x000055e092b971c0@/repo/Rakefile:10>, #<Proc:0x000055e092b971c0@/repo/Rakefile:10>, #<Proc:0x000055e092b971c0@/repo/Rakefile:10>, #<Proc:0x000055e092b971c0@/repo/Rakefile:10>]
"target => source"
[#<Proc:0x000055e092b971c0@/repo/Rakefile:10>, #<Proc:0x000055e092b971c0@/repo/Rakefile:10>, #<Proc:0x000055e092b971c0@/repo/Rakefile:10>, #<Proc:0x000055e092b971c0@/repo/Rakefile:10>, #<Proc:0x000055e092b971c0@/repo/Rakefile:10>]
"target => source"
[#<Proc:0x000055e092b971c0@/repo/Rakefile:10>, #<Proc:0x000055e092b971c0@/repo/Rakefile:10>, #<Proc:0x000055e092b971c0@/repo/Rakefile:10>, #<Proc:0x000055e092b971c0@/repo/Rakefile:10>, #<Proc:0x000055e092b971c0@/repo/Rakefile:10>]
"target => source"
[#<Proc:0x000055e092b971c0@/repo/Rakefile:10>, #<Proc:0x000055e092b971c0@/repo/Rakefile:10>, #<Proc:0x000055e092b971c0@/repo/Rakefile:10>, #<Proc:0x000055e092b971c0@/repo/Rakefile:10>, #<Proc:0x000055e092b971c0@/repo/Rakefile:10>]
** Execute d
** Invoke target 
** Execute b
** Invoke target 
** Execute a
** Invoke target 
** Execute c
** Invoke target 
** Execute e
** Execute default

The results differ between runs. It seems to happen more often with debug output.

The same action block gets added multiple times to the same task.

Reproduziere das Problem mit der bereitgestellten Rakefile-Datei unter Verwendung von rake --trace --rules, wobei die Debug-Ausgabe und wiederholte Ausführungen variiert werden. Verfolge die Einstiegspunkte von multitask und rule-resolution, um festzustellen, warum dieselbe Aktion wiederholt hinzugefügt wird; fertig ist die Aufgabe, wenn die Aktion des gemeinsamen Ziels konsistent genau einmal ausgeführt wird.