(MODULES-3590) Fix match_for_absence parameter

Prior to this commit, due to a bug in the exists? method in the
file_line provider, match_for_absence didn't work as described (or
at all really). Update the exists? logic so that match_for_absence
works as described.

Additionally add a unit test to prevent regressions and update the
documentation for the parameter to reflect the fact that it is
ignored when `ensure => present`.

4 files changed, 15 insertions, 3 deletions

diff --git a/README.markdown b/README.markdown
index d27668b..34d26a8 100644
--- a/README.markdown
+++ b/README.markdown
@@ -128,7 +128,7 @@ All parameters are optional, unless otherwise noted.
 * `ensure`: Ensures whether the resource is present. Valid options: 'present', 'absent'. Default: 'present'.
 * `line`: **Required.** Sets the line to be added to the file located by the `path` parameter. Valid options: String. Default: Undefined.
 * `match`: Specifies a regular expression to run against existing lines in the file; if a match is found, it is replaced rather than adding a new line. A regex comparison is performed against the line value, and if it does not match, an exception is raised. Valid options: String containing a regex. Default: Undefined.
-* `match_for_absence`: An optional value to determine if match should be applied when `ensure => absent`. If set to true and match is set, the line that matches match will be deleted. If set to false (the default), match is ignored when `ensure => absent` and the value of `line` is used instead. Default: false.
+* `match_for_absence`: An optional value to determine if match should be applied when `ensure => absent`. If set to true and match is set, the line that matches match will be deleted. If set to false (the default), match is ignored when `ensure => absent` and the value of `line` is used instead. Ignored when `ensure => present`. Default: false.
 * `multiple`: Determines if `match` and/or `after` can change multiple lines. If set to false, an exception will be raised if more than one line matches. Valid options: 'true', 'false'. Default: Undefined.
 * `name`: Sets the name to use as the identity of the resource. This is necessary if you want the resource namevar to differ from the supplied `title` of the resource. Valid options: String. Default: Undefined.
 * `path`: **Required.** Defines the file in which Puppet will ensure the line specified by `line`. Must be an absolute path to the file.
diff --git a/lib/puppet/provider/file_line/ruby.rb b/lib/puppet/provider/file_line/ruby.rb
index aab6fe2..beeb430 100644
--- a/lib/puppet/provider/file_line/ruby.rb
+++ b/lib/puppet/provider/file_line/ruby.rb
@@ -4,7 +4,11 @@ Puppet::Type.type(:file_line).provide(:ruby) do
       true
     else
       lines.find do |line|
-        line.chomp == resource[:line].chomp
+        if resource[:ensure].to_s == 'absent' and resource[:match_for_absence].to_s == 'true'
+          line.chomp =~ Regexp.new(resource[:match])
+        else
+          line.chomp == resource[:line].chomp
+        end
       end
     end
   end
diff --git a/lib/puppet/type/file_line.rb b/lib/puppet/type/file_line.rb
index 6f5c188..7b7d44e 100644
--- a/lib/puppet/type/file_line.rb
+++ b/lib/puppet/type/file_line.rb
@@ -71,7 +71,8 @@ Puppet::Type.newtype(:file_line) do
   newparam(:match_for_absence) do
     desc 'An optional value to determine if match should be applied when ensure => absent.' +
          ' If set to true and match is set, the line that matches match will be deleted.' +
-         ' If set to false (the default), match is ignored when ensure => absent.'
+         ' If set to false (the default), match is ignored when ensure => absent.' +
+         ' When `ensure => present`, match_for_absence is ignored.'
     newvalues(true, false)
     defaultto false
   end
diff --git a/spec/unit/puppet/provider/file_line/ruby_spec.rb b/spec/unit/puppet/provider/file_line/ruby_spec.rb
index fdeaf1a..1f41f62 100755
--- a/spec/unit/puppet/provider/file_line/ruby_spec.rb
+++ b/spec/unit/puppet/provider/file_line/ruby_spec.rb
@@ -363,6 +363,13 @@ describe provider_class do
       @provider = provider_class.new(@resource)
     end
 
+    it 'should find a line to match' do
+      File.open(@tmpfile, 'w') do |fh|
+        fh.write("foo1\nfoo\nfoo2")
+      end
+      expect(@provider.exists?).to be_truthy
+    end
+
     it 'should remove one line if it matches' do
       File.open(@tmpfile, 'w') do |fh|
         fh.write("foo1\nfoo\nfoo2")