iconv deprecation warning with ruby 1.9.3

Question

I\'m getting this warning when I run rspec:

/gems/activesupport-3.1.0/lib/active_support/dependencies.rb:240:in `block in require\': iconv will be deprecated in          


        

Answer 1

To remove this warning...

go to your .rvm directory and find iconv.c (mine was at ~/.rvm/src/ruby-1.9.3-p125/ext/iconv/iconv.c)

edit that file are remove or comment out the call to warn_deprecated() (should be near the bottom)

from that file's directory, run ruby extconf.rb then make then make install

Should do the trick

Answer 2

You can pin down the exact location of the warning by generating exceptions for ActiveSupport::Deprecation, instead of just printing to the log. At the top of application.rb:

ActiveSupport::Deprecation.behavior = Proc.new do |message, backtrace|
  raise message
end

Once you've figured out where the warning is coming from (by inspecting the full backtrace), remove this again.

Answer 3

Add this to the start of your program:

oldverb = $VERBOSE; $VERBOSE = nil
require 'iconv'
$VERBOSE = oldverb

and curse the people who think this is a professional way to handle deprecation.

Answer 4

You are getting this deprecation notice cause a library somewhere is requiring iconv.

iconv is a gem created by Matz that can be used to convert strings from one format to another.

For example this is often used:

Iconv.iconv('UTF-8//IGNORE', 'UTF-8', content) this little bit of magic takes a UTF-8 string that may have invalid chars and converts it to a proper UTF-8 string.

It has been decided that in Ruby 1.9.3 we should not be using iconv any more and instead use the built-in String#encode. encode is more powerful and allows you more flexibility.

The theory is that the above example could be replaced with:

string.encode("UTF-8", :invalid => :replace, :undef => :replace, :replace => "?")

In practice it seems this is imperfect.

This also leads to a less than easy story for gem creators who wish to support 1.8:

content = RUBY_VERSION.to_f < 1.9 ? 
  Iconv.iconv('UTF-8//IGNORE', 'UTF-8',  "content") :
  "#{content}".encode(Encoding::UTF_8, :invalid => :replace, :undef => :replace, :replace => '')

---

So, you have a gem somewhere that is requiring iconv, to find it:

Assuming your error message is: /gems/activesupport-3.1.0/lib/active_support/dependencies.rb:240

Open up /gems/activesupport-3.1.0/lib/active_support/dependencies.rb on line 240:

Add the line:

p caller if file =~ /iconv/

(just after: load_dependency(file) { result = super })

You will get a big fat stack trace:

 rake --tasks
/home/sam/.rvm/gems/ruby-1.9.3-p125/gems/activesupport-3.2.6/lib/active_support/dependencies.rb:251:in `block in require': iconv will be deprecated in the future, use String#encode instead.
["/home/sam/.rvm/gems/ruby-1.9.3-p125/gems/calais-0.0.13/lib/calais.rb:5:in `'", 
.. more omitted ..

This tells me it is the calais gem. Looking through pull requests, I am not the first. The pull has not been yanked in.

---

Depending on the gem, there may be an upgraded version that does not have this error, so I would recommend you upgrade your gems first. If you are unlucky you may be stuck with the unfortunate task of forking a gem to get rid of this (if for example your pull request to fix it languishes)

Answer 5

If you're seeing this, it's very probably not Rails. If you look at the method surrounding the line being referred to in the error you posted, you'll see the following:

def require(file, *)
  result = false
  load_dependency(file) { result = super }
  result
end

I'm not saying it's your code, necessarily, but I'm certain that it's not actually the line in question where iconv is being called. In my case, I found that my project's code actually contained a reference to iconv.

If you want to check your code for such a reference, try grep -ir iconv ./ in your project directory.

When iconv is actually in a library it can be harder to find. By temporarily changing the above method to:

def require(file, *)
  result = false
  puts
  puts caller.reverse
  load_dependency(file) { result = super }
  result
end

You can then easily run your code and grep out the relevant lines of the backtrace to find the root cause of the warning.

ruby your/code.rb 2>&1 | grep -B 5 iconv