Editing text using $EDITOR from program

Ruby
1

Does Highline or Thor/Facets/ActiveSupport etc have a method for when
you want user to edit multiline text using the $EDITOR value?

Commander has but it does not work with vim. So i wrote a method, if
anyone has time please give it a look and give me feedback. Is it
correct to pass back a nil if user does not edit, or should I pass a
blank String.

Thanks. (File attached).
http://gist.github.com/456809

Also, following is the method “commander” has. It is supposed to work
with TextMate but does not with Vim. It does open TextEdit in the
background, but does not seem to put the text in it.

def ask_editor input = nil, editor = ENV[‘EDITOR’] || ‘mate’
IO.popen(editor.to_s, ‘w+’) do |pipe|
pipe.puts input.to_s unless input.nil?
pipe.close_write
pipe.read
end
end

I’d like to know why the developer of commander used this instead of a
“system” command. In what way is this superior ? Why does it fail with
vim.

2

On 6/28/10, R… Kumar [email protected] wrote:

Does Highline or Thor/Facets/ActiveSupport etc have a method for when
you want user to edit multiline text using the $EDITOR value?

Ok, this was a week ago now, but no one else has responded.

Commander has but it does not work with vim.
[snip]
end
This code is wrong. EDITOR is supposed to be set to a text-mode
editor, which runs inside a text terminal environment. If the user has
a graphical editor he wants to use, such as gvim, gnotepad, or
textmate, he should set the VISUAL environment variable instead.
ask_editor or equivalent code should look for VISUAL first and then
EDITOR only if VISUAL is not set.

A gui editor needs to be called in a different way than a text-mode
editor is called. A gui editor needs no controlling text-mode
terminal, whereas a text-mode editor requires one. A gui editor should
be called asynchronously whereas a text-mode editor must be called
synchronously. A gui editor doesn’t (really) use stdin/stdout/stderr
whereas a text-mode editor must use them.

The code above is designed to be used with a gui editor, even tho it
consults the EDITOR environment variable. It starts the editor process
asynchronously. It captures the subprocess’s stdin and uses it for a
different purpose, which prevents vim from ever getting any input from
the user.
These factors sccount for the problems you observed, I believe.
ENV[‘EDITOR’] in that method should be replaced with ENV[‘VISUAL’].
(And it should be expanded to use EDITOR if that is set as well…)

So i wrote a method, if
anyone has time please give it a look and give me feedback. Is it
correct to pass back a nil if user does not edit, or should I pass a
blank String.

Thanks. (File attached).
http://gist.github.com/456809

I’d like to know why the developer of commander used this instead of a
“system” command. In what way is this superior ? Why does it fail with
vim.

Attachments:
http://www.ruby-forum.com/attachment/4822/edit.rb

Your code looks pretty good to me. You really ought to check for
VISUAL as well, as I outlined above. If VISUAL is set, do something
like what the ask_editor code you posted above is doing. Except I
don’t think you should assume you can use stdin and stdout to
communicate with a gui editor; that sounds too textmate specific to
me. Working with temp files like you have for the EDITOR case is the
most portable and general plan.

Some other minor nits:

  1. quote all words on the command line, to handle spaces in filenames
    better. Better yet, break the command line up into words, or rather
    don’t join them together in one line. So, replace
    system(“#{ed} #{temp.path}”)
    with
    system(ed, temp.path)

  2. I’d just read the whole file in one big slirp instead of line by
    line. (Unless you think you’re user is really going to write a whole
    lot of stuff… in which case you need to rewrite anyway.)

3

Caleb C. wrote:

On 6/28/10, R… Kumar [email protected] wrote:

Does Highline or Thor/Facets/ActiveSupport etc have a method for when
you want user to edit multiline text using the $EDITOR value?

system(“#{ed} #{temp.path}”)
with
system(ed, temp.path)

  1. I’d just read the whole file in one big slirp instead of line by
    line. (Unless you think you’re user is really going to write a whole
    lot of stuff… in which case you need to rewrite anyway.)

Thanks a lot for your feedback. Could you give me some on this other
issue.

I am mailing some data to the user using the system “cat file | mail -s
“title” [email protected]” format.
I’ve used the system() for this and it works fine. I am doing a “cat”
rather than “echo” since the data can have single or double quotes. Is
it okay to use the system command this way, with a pipe inside it ?
Looks clumsy to me!

I looked back some old code of mine where i used “sendmail” and there I
do:

def pipe_output (str)
pipeto = ‘/usr/sbin/sendmail -t’
if pipeto != nil # i was taking pipeto from a hash, so checking
proc = IO.popen(pipeto, “w+”)
proc.puts str
proc.close_write
#@main.log.info(proc.gets)
end
end

This works fine, too.

However, since “mail -s” requires both input, as well as some command
line parameters (title and emailid), i was not clear whether this method
would work.

thx.

4

On 7/6/10, R… Kumar 1.9.1 OSX [email protected] wrote:

str = “this is some data to go in mail”
pipe_output str

Not sure which is cleaner and more reliable though, this way or:

cmd = %q{cat file.txt | mail -s “title” email}
system(cmd)

Either way should work fine, but I would go with popen, personally. I
think it’s a little cleaner semantically; might be a tad more portable
too.

5

R… Kumar 1.9.1 OSX wrote:

However, since “mail -s” requires both input, as well as some command
line parameters (title and emailid), i was not clear whether this method
would work.

thx.

This works:

def pipe_output (str)

pipeto = %q{mail -s "a title" myemail }
if pipeto != nil  # i was taking pipeto from a hash, so checking
  proc = IO.popen(pipeto, "w+")
  proc.puts str
  proc.close_write
  #puts proc.gets
end

end

str = “this is some data to go in mail”
pipe_output str

Not sure which is cleaner and more reliable though, this way or:

cmd = %q{cat file.txt | mail -s “title” email}
system(cmd)