* [ruby-dev:51089] [Ruby master Bug#18069] `instance_exec` is just ignored when the block is originally a method
@ 2021-08-08 14:30 info
2021-08-09 19:00 ` [ruby-dev:51091] [Ruby master Feature#18069] " merch-redmine
2021-08-10 5:33 ` [ruby-dev:51092] " nobu
0 siblings, 2 replies; 3+ messages in thread
From: info @ 2021-08-08 14:30 UTC (permalink / raw)
To: ruby-dev
Issue #18069 has been reported by ttanimichi (Tsukuru Tanimichi).
----------------------------------------
Bug #18069: `instance_exec` is just ignored when the block is originally a method
https://bugs.ruby-lang.org/issues/18069
* Author: ttanimichi (Tsukuru Tanimichi)
* Status: Open
* Priority: Normal
* Backport: 2.6: UNKNOWN, 2.7: UNKNOWN, 3.0: UNKNOWN
----------------------------------------
I know you can't `instance_exec` a proc which is generated by `Method#to_proc` because it has its original instance's context. But, in such a case, raising `ArgumentError` would be the ideal behavior.
```ruby
f = -> (x) { a + x }
class A
def a
1
end
end
A.new.instance_exec(1, &f) # => 2
class B
def b(x)
a + x
end
end
proc = B.new.method(:b).to_proc
A.new.instance_exec(1, &proc) # => undefined local variable or method `a' for #<B:0x00007fdaf30480a0> (NameError)
```
--
https://bugs.ruby-lang.org/
^ permalink raw reply [flat|nested] 3+ messages in thread
* [ruby-dev:51091] [Ruby master Feature#18069] `instance_exec` is just ignored when the block is originally a method
2021-08-08 14:30 [ruby-dev:51089] [Ruby master Bug#18069] `instance_exec` is just ignored when the block is originally a method info
@ 2021-08-09 19:00 ` merch-redmine
2021-08-10 5:33 ` [ruby-dev:51092] " nobu
1 sibling, 0 replies; 3+ messages in thread
From: merch-redmine @ 2021-08-09 19:00 UTC (permalink / raw)
To: ruby-dev
Issue #18069 has been updated by jeremyevans0 (Jeremy Evans).
Backport deleted (2.6: UNKNOWN, 2.7: UNKNOWN, 3.0: UNKNOWN)
Tracker changed from Bug to Feature
I don't think the current behavior is a bug. `Method#to_proc` is currently equivalent to:
```ruby
class Method
def to_proc
method = self
->(*args, **kwargs, &block) do
method.call(*args, **kwargs, &block)
end
end
end
```
You wouldn't expect an `instance_exec` on that lambda to change the behavior of `Method#call`. So I think the current behavior is expected.
Note that it's not hard to change the behavior to raise an error in this case (and other cases like `module_exec`). However, changing the behavior would result in significant backwards compatibility issues. I tried a commit that raises ArgumentError in such a case: https://github.com/jeremyevans/ruby/commit/3e2db2f01281f2335c638142223f8b24531826bd. However, it broke quite a few tests: https://github.com/jeremyevans/ruby/runs/3283493124. Some of the breakage may be due to implementation choice, but I checked and at least some of the breakage is unavoidable as the tests expect to pass procs created by `Method#to_proc` to `instance_exec` (e.g. `test_instance_exec_define_method_kwsplat`).
As I don't think this is a bug, I'm switching this to a feature request.
----------------------------------------
Feature #18069: `instance_exec` is just ignored when the block is originally a method
https://bugs.ruby-lang.org/issues/18069#change-93200
* Author: ttanimichi (Tsukuru Tanimichi)
* Status: Open
* Priority: Normal
----------------------------------------
I know you can't `instance_exec` a proc which is generated by `Method#to_proc` because it has its original instance's context. But, in such a case, raising `ArgumentError` would be the ideal behavior.
```ruby
f = -> (x) { a + x }
class A
def a
1
end
end
A.new.instance_exec(1, &f) # => 2
class B
def b(x)
a + x
end
end
proc = B.new.method(:b).to_proc
A.new.instance_exec(1, &proc) # => undefined local variable or method `a' for #<B:0x00007fdaf30480a0> (NameError)
```
--
https://bugs.ruby-lang.org/
^ permalink raw reply [flat|nested] 3+ messages in thread
* [ruby-dev:51092] [Ruby master Feature#18069] `instance_exec` is just ignored when the block is originally a method
2021-08-08 14:30 [ruby-dev:51089] [Ruby master Bug#18069] `instance_exec` is just ignored when the block is originally a method info
2021-08-09 19:00 ` [ruby-dev:51091] [Ruby master Feature#18069] " merch-redmine
@ 2021-08-10 5:33 ` nobu
1 sibling, 0 replies; 3+ messages in thread
From: nobu @ 2021-08-10 5:33 UTC (permalink / raw)
To: ruby-dev
Issue #18069 has been updated by nobu (Nobuyoshi Nakada).
A method is bound to the internal states of the receiver.
I don't think that removing the receiver from a method makes sense.
----------------------------------------
Feature #18069: `instance_exec` is just ignored when the block is originally a method
https://bugs.ruby-lang.org/issues/18069#change-93211
* Author: ttanimichi (Tsukuru Tanimichi)
* Status: Open
* Priority: Normal
----------------------------------------
I know you can't `instance_exec` a proc which is generated by `Method#to_proc` because it has its original instance's context. But, in such a case, raising `ArgumentError` would be the ideal behavior.
```ruby
f = -> (x) { a + x }
class A
def a
1
end
end
A.new.instance_exec(1, &f) # => 2
class B
def b(x)
a + x
end
end
proc = B.new.method(:b).to_proc
A.new.instance_exec(1, &proc) # => undefined local variable or method `a' for #<B:0x00007fdaf30480a0> (NameError)
```
--
https://bugs.ruby-lang.org/
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2021-08-10 5:33 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-08-08 14:30 [ruby-dev:51089] [Ruby master Bug#18069] `instance_exec` is just ignored when the block is originally a method info
2021-08-09 19:00 ` [ruby-dev:51091] [Ruby master Feature#18069] " merch-redmine
2021-08-10 5:33 ` [ruby-dev:51092] " nobu
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).