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authorKen Barber <ken@bob.sh>2011-08-05 08:52:00 +0100
committerKen Barber <ken@bob.sh>2011-08-05 10:31:46 +0100
commitaa27fc76c7d5fa090ea1d47027856c3e70c6ae8f (patch)
treedc9a4ae93fc7345d719de29d956f6488c1b69005 /lib/puppet/parser/functions/shuffle.rb
parent07d0eca31780bba76f2283ce83f944473ce8fe00 (diff)
parent1b73a66fc67af0e33fa41aacf50654d4a7a4903c (diff)
(#8797) Merge puppetlabs-functions into puppetlabs-stdlib
It was decided that maintaining puppetlabs-functions and puppetlabs-stdlib was duplication as both are trying to achieve the same goal. This patch provides a merge of the puppetlabs-functions into the puppetlabs-stdlib repository, with history preservation. The following conflicts were found and resolved: * LICENSE file from functions was used as it aligns with ASL usage instructions and contains relevant copyright information: http://www.apache.org/licenses/LICENSE-2.0.html * Used spec_helper.rb from functions - this is what Puppet core uses and doesn't break tests. * Merged .gitignore and spec.opts options.
Diffstat (limited to 'lib/puppet/parser/functions/shuffle.rb')
-rw-r--r--lib/puppet/parser/functions/shuffle.rb46
1 files changed, 46 insertions, 0 deletions
diff --git a/lib/puppet/parser/functions/shuffle.rb b/lib/puppet/parser/functions/shuffle.rb
new file mode 100644
index 0000000..18134ab
--- /dev/null
+++ b/lib/puppet/parser/functions/shuffle.rb
@@ -0,0 +1,46 @@
+#
+# shuffle.rb
+#
+
+module Puppet::Parser::Functions
+ newfunction(:shuffle, :type => :rvalue, :doc => <<-EOS
+Randomizes the order of a string or array elements.
+ EOS
+ ) do |arguments|
+
+ raise(Puppet::ParseError, "shuffle(): Wrong number of arguments " +
+ "given (#{arguments.size} for 1)") if arguments.size < 1
+
+ value = arguments[0]
+ klass = value.class
+
+ unless [Array, String].include?(klass)
+ raise(Puppet::ParseError, 'shuffle(): Requires either ' +
+ 'array or string to work with')
+ end
+
+ result = value.clone
+
+ string = value.is_a?(String) ? true : false
+
+ # Check whether it makes sense to shuffle ...
+ return result if result.size <= 1
+
+ # We turn any string value into an array to be able to shuffle ...
+ result = string ? result.split('') : result
+
+ elements = result.size
+
+ # Simple implementation of Fisher–Yates in-place shuffle ...
+ elements.times do |i|
+ j = rand(elements - i) + i
+ result[j], result[i] = result[i], result[j]
+ end
+
+ result = string ? result.join : result
+
+ return result
+ end
+end
+
+# vim: set ts=2 sw=2 et :