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Feat/Bug: Set the value of `_` (underscore) to the value of the last ruby expression

Aperta
#1,069 3 commenti 2 reazioni 0 assegnatari Vedi su GitHub

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Valutazione

Difficoltà
4/5
Tempo stimato
3-5 giorni
Idoneità per principianti
42/100
Tipo di issue
Bug
Chiarezza
Abbastanza chiara
Stato di attività
Ferma
Stack tecnologico
ruby
Ambito
devtools

Direzione di ricerca

Start with the irb_integration.rb entry point named in the trace and reproduce the supplied IRB session while comparing normal and debug modes. Done means _ continues to hold the last Ruby expression's value after entering debug mode, without debug commands or errors replacing it.

Scritto dal modello di indicizzazione a partire dal testo della issue.

Descrizione

Your proposal

Pry and IRB have a feature in which _ is always set the the value of the last expression. While I realize it may not make sense to do this with debug commands, it would be nice if the feature was there at least for Ruby expressions. The current behavior seems to be setting _ to the last error, but seemingly only for debug commands like ls. This is kind of a bug in the irb_console since IRB has this feature normally but it stops working after entering debug mode.

Additional context

Shell session: 

irb(#<Foobar:0x000000011efeb9f0>):001> 3+3
=> 6

irb(#<Foobar:0x000000011efeb9f0>):002> puts _
6
=> nil

irb(#<Foobar:0x000000011efeb9f0>):003> 4+4
=> 8

irb(#<Foobar:0x000000011efeb9f0>):004> info
(rdbg:irb) info
%self = #<Foobar:0x000000011efeb9f0 @foo="bar">
@foo = "bar"

irb:rdbg(#<Foobar:0x000000011efeb9f0>):002> puts _

nil

irb:rdbg(#<Foobar:0x000000011efeb9f0>):003> 4+4
8

irb:rdbg(#<Foobar:0x000000011efeb9f0>):004> puts _

nil
irb:rdbg(#<Foobar:0x000000011efeb9f0>):005> 4+4
8

irb:rdbg(#<Foobar:0x000000011efeb9f0>):006> info
%self = #<Foobar:0x000000011efeb9f0 @foo="bar">
_ = nil
@foo = "bar"

irb:rdbg(#<Foobar:0x000000011efeb9f0>):007> ls Bar
Traceback (most recent call last):
	24: from /Users/joesharp/.asdf/installs/ruby/2.7.8/lib/ruby/gems/2.7.0/gems/debug-1.9.1/lib/debug/session.rb:212:in `block in activate'
	23: from /Users/joesharp/.asdf/installs/ruby/2.7.8/lib/ruby/gems/2.7.0/gems/debug-1.9.1/lib/debug/session.rb:254:in `session_server_main'
	22: from /Users/joesharp/.asdf/installs/ruby/2.7.8/lib/ruby/gems/2.7.0/gems/debug-1.9.1/lib/debug/session.rb:365:in `process_event'
	21: from /Users/joesharp/.asdf/installs/ruby/2.7.8/lib/ruby/gems/2.7.0/gems/debug-1.9.1/lib/debug/session.rb:403:in `wait_command_loop'
	20: from /Users/joesharp/.asdf/installs/ruby/2.7.8/lib/ruby/gems/2.7.0/gems/debug-1.9.1/lib/debug/session.rb:403:in `loop'
	19: from /Users/joesharp/.asdf/installs/ruby/2.7.8/lib/ruby/gems/2.7.0/gems/debug-1.9.1/lib/debug/session.rb:404:in `block in wait_command_loop'
	18: from /Users/joesharp/.asdf/installs/ruby/2.7.8/lib/ruby/gems/2.7.0/gems/debug-1.9.1/lib/debug/session.rb:444:in `wait_command'
	15: from /Users/joesharp/.asdf/installs/ruby/2.7.8/lib/ruby/gems/2.7.0/gems/debug-1.9.1/lib/debug/session.rb:1981:in `intercept_trap_sigint'
	 4: from /Users/joesharp/.asdf/installs/ruby/2.7.8/lib/ruby/gems/2.7.0/gems/debug-1.9.1/lib/debug/irb_integration.rb:9:in `evaluate'
(irb):7:in `set_foo': uninitialized constant Foobar::Bar (NameError)`

irb:rdbg(#<Foobar:0x000000011efeb9f0>):008> puts _
uninitialized constant Foobar::Bar
nil

irb:rdbg(#<Foobar:0x000000011efeb9f0>):009> ls Bar
Traceback (most recent call last):
	24: from /Users/joesharp/.asdf/installs/ruby/2.7.8/lib/ruby/gems/2.7.0/gems/debug-1.9.1/lib/debug/session.rb:212:in `block in activate'
	23: from /Users/joesharp/.asdf/installs/ruby/2.7.8/lib/ruby/gems/2.7.0/gems/debug-1.9.1/lib/debug/session.rb:254:in `session_server_main'
	22: from /Users/joesharp/.asdf/installs/ruby/2.7.8/lib/ruby/gems/2.7.0/gems/debug-1.9.1/lib/debug/session.rb:365:in `process_event'
	21: from /Users/joesharp/.asdf/installs/ruby/2.7.8/lib/ruby/gems/2.7.0/gems/debug-1.9.1/lib/debug/session.rb:403:in `wait_command_loop'
	20: from /Users/joesharp/.asdf/installs/ruby/2.7.8/lib/ruby/gems/2.7.0/gems/debug-1.9.1/lib/debug/session.rb:403:in `loop'
	19: from /Users/joesharp/.asdf/installs/ruby/2.7.8/lib/ruby/gems/2.7.0/gems/debug-1.9.1/lib/debug/session.rb:404:in `block in wait_command_loop'
	18: from /Users/joesharp/.asdf/installs/ruby/2.7.8/lib/ruby/gems/2.7.0/gems/debug-1.9.1/lib/debug/session.rb:444:in `wait_command'
	15: from /Users/joesharp/.asdf/installs/ruby/2.7.8/lib/ruby/gems/2.7.0/gems/debug-1.9.1/lib/debug/session.rb:1981:in `intercept_trap_sigint'
	 4: from /Users/joesharp/.asdf/installs/ruby/2.7.8/lib/ruby/gems/2.7.0/gems/debug-1.9.1/lib/debug/irb_integration.rb:9:in `evaluate'
(irb):9:in `set_foo': uninitialized constant Foobar::Bar (NameError)`

irb:rdbg(#<Foobar:0x000000011efeb9f0>):010> info
%self = #<Foobar:0x000000011efeb9f0 @foo="bar">
_ = #<NameError: uninitialized constant Foobar::Bar>
@foo = "bar"

irb:rdbg(#<Foobar:0x000000011efeb9f0>):011> Bar.methods
eval error: uninitialized constant Foobar::Bar
  (rdbg)/scratch.rb:1:in `set_foo'`
nil

irb:rdbg(#<Foobar:0x000000011efeb9f0>):012> info
%self = #<Foobar:0x000000011efeb9f0 @foo="bar">
_ = nil
@foo = "bar"

irb:rdbg(#<Foobar:0x000000011efeb9f0>):013> Bar.methods
eval error: uninitialized constant Foobar::Bar
  (rdbg)/scratch.rb:1:in `set_foo'`
nil

irb:rdbg(#<Foobar:0x000000011efeb9f0>):014> puts _

nil

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