Allow variable $0 to $9 to be interpolated, if ephemeral

Signed-off-by: Brice Figureau <brice-puppet@daysofwonder.com>

2 files changed, 37 insertions, 2 deletions

diff --git a/lib/puppet/parser/scope.rb b/lib/puppet/parser/scope.rb
index 5b3c6d04a..71b9be27c 100644
--- a/lib/puppet/parser/scope.rb
+++ b/lib/puppet/parser/scope.rb
@@ -331,12 +331,17 @@ class Puppet::Parser::Scope
         ss = StringScanner.new(string)
         out = ""
         while not ss.eos?
-            if ss.scan(/^\$\{((\w*::)*\w+)\}|^\$((\w*::)*\w+)/)
+            if ss.scan(/^\$\{((\w*::)*\w+|[0-9]+)\}|^\$([0-9])|^\$((\w*::)*\w+)/)
                 # If it matches the backslash, then just retun the dollar sign.
                 if ss.matched == '\\$'
                     out << '$'
                 else # look the variable up
-                    out << lookupvar(ss[1] || ss[3]).to_s || ""
+                    # make sure $0-$9 are lookupable only if ephemeral
+                    var = ss[1] || ss[3] || ss[4]
+                    if var and var =~ /^[0-9]+$/ and not ephemeral?(var)
+                        next
+                    end
+                    out << lookupvar(var).to_s || ""
                 end
             elsif ss.scan(/^\\(.)/)
                 # Puppet.debug("Got escape: pos:%d; m:%s" % [ss.pos, ss.matched])
diff --git a/spec/unit/parser/scope.rb b/spec/unit/parser/scope.rb
index 641a3f946..665b2ed63 100755
--- a/spec/unit/parser/scope.rb
+++ b/spec/unit/parser/scope.rb
@@ -223,6 +223,36 @@ describe Puppet::Parser::Scope do
         end
     end
 
+    describe "when interpolating string" do
+        (0..9).each do |n|
+            it "should allow $#{n} to match" do
+                @scope.setvar(n.to_s, "value", :ephemeral => true)
+
+                @scope.strinterp("$#{n}").should == "value"
+            end
+        end
+
+        (0..9).each do |n|
+            it "should not allow $#{n} to match if not ephemeral" do
+                @scope.setvar(n.to_s, "value", :ephemeral => false)
+
+                @scope.strinterp("$#{n}").should_not == "value"
+            end
+        end
+
+        it "should not allow $10 to match" do
+            @scope.setvar("10", "value", :ephemeral => true)
+
+            @scope.strinterp('==$10==').should_not == "==value=="
+        end
+
+        it "should not allow ${10} to match" do
+            @scope.setvar("10", "value", :ephemeral => true)
+
+            @scope.strinterp('==${10}==').should == "==value=="
+        end
+    end
+
     describe "when setting ephemeral vars from matches" do
         before :each do
             @match = stub 'match', :is_a? => true