Extend delete function for strings and hashes

Previous to this commit, the delete function only acted on
arrays. This commit adds the same functionality for hashes and strings
in the obvious way: delete(h, k) would delete the k key from the h
hash and delete(s, sub) would delete all instances of the sub
substring from the s string.

diff --git a/lib/puppet/parser/functions/delete.rb b/lib/puppet/parser/functions/delete.rb
index ab8f75bdb1ecf002cedb4ba3069b7dac861921ec..f81434409c718b42cebbbaac105d4e87df70cfb8 100644 (file)
--- a/lib/puppet/parser/functions/delete.rb
+++ b/lib/puppet/parser/functions/delete.rb
@@ -3,31 +3,43 @@
 #
 
 # TODO(Krzysztof Wilczynski): We need to add support for regular expression ...
-# TODO(Krzysztof Wilczynski): Support for strings and hashes too ...
 
 module Puppet::Parser::Functions
   newfunction(:delete, :type => :rvalue, :doc => <<-EOS
-Deletes a selected element from an array.
+Deletes all instances of a given element from an array, substring from a
+string, or key from a hash.
 
 *Examples:*
 
-    delete(['a','b','c'], 'b')
+    delete(['a','b','c','b'], 'b')
+    Would return: ['a','c']
 
-Would return: ['a','c']
+    delete({'a'=>1,'b'=>2,'c'=>3}, 'b')
+    Would return: {'a'=>1,'c'=>3}
+
+    delete('abracadabra', 'bra')
+    Would return: 'acada'
     EOS
   ) do |arguments|
 
     if (arguments.size != 2) then
       raise(Puppet::ParseError, "delete(): Wrong number of arguments "+
-        "given #{arguments.size} for 2")
+        "given #{arguments.size} for 2.")
     end
 
-    a = arguments[0]
+    collection = arguments[0]
     item = arguments[1]
 
-    a.delete(item)
-    a
-
+    case collection
+    when Array, Hash
+      collection.delete item
+    when String
+      collection.gsub! item, ''
+    else
+      raise(TypeError, "delete(): First argument must be an Array, " +
+            "String, or Hash. Given an argument of class #{collection.class}.")
+    end
+    collection
   end
 end
 

diff --git a/spec/unit/puppet/parser/functions/delete_spec.rb b/spec/unit/puppet/parser/functions/delete_spec.rb
index 0549232a55cb1c6db5dfd71b2ea57339bfe60489..2f29c93c0ce1349a096e29652f405c3a1a3f2b88 100755 (executable)
--- a/spec/unit/puppet/parser/functions/delete_spec.rb
+++ b/spec/unit/puppet/parser/functions/delete_spec.rb
@@ -8,12 +8,31 @@ describe "the delete function" do
     Puppet::Parser::Functions.function("delete").should == "function_delete"
   end
 
-  it "should raise a ParseError if there is less than 1 arguments" do
+  it "should raise a ParseError if there are fewer than 2 arguments" do
     lambda { scope.function_delete([]) }.should( raise_error(Puppet::ParseError))
   end
 
-  it "should delete an item from an array" do
-    result = scope.function_delete([['a','b','c'],'b'])
+  it "should raise a ParseError if there are greater than 2 arguments" do
+    lambda { scope.function_delete([[], 'foo', 'bar']) }.should( raise_error(Puppet::ParseError))
+  end
+
+  it "should raise a TypeError if a number is passed as the first argument" do
+    lambda { scope.function_delete([1, 'bar']) }.should( raise_error(TypeError))
+  end
+
+  it "should delete all instances of an element from an array" do
+    result = scope.function_delete([['a','b','c','b'],'b'])
     result.should(eq(['a','c']))
   end
+
+  it "should delete all instances of a substring from a string" do
+    result = scope.function_delete(['foobarbabarz','bar'])
+    result.should(eq('foobaz'))
+  end
+
+  it "should delete a key from a hash" do
+    result = scope.function_delete([{ 'a' => 1, 'b' => 2, 'c' => 3 },'b'])
+    result.should(eq({ 'a' => 1, 'c' => 3 }))
+  end
+
 end