(maint) Clarify docs and add new tests

Based on a Stack Overflow question, it was noted that the documentation
for `file_line` isn't complete and the underlying behaviour somewhat
confusing.

https://stackoverflow.com/questions/46468922/how-to-change-the-contents-of-a-file-by-using-puppet/46473458

In this patch I add additional unit tests and better examples and
complete documentation.

1 files changed, 3 insertions, 0 deletions

diff --git a/spec/unit/puppet/type/file_line_spec.rb b/spec/unit/puppet/type/file_line_spec.rb
index 150149b..db07352 100755
--- a/spec/unit/puppet/type/file_line_spec.rb
+++ b/spec/unit/puppet/type/file_line_spec.rb
@@ -78,6 +78,9 @@ describe Puppet::Type.type(:file_line) do
   it 'should not require that a line is specified when matching for absence' do
     expect { Puppet::Type.type(:file_line).new(:name => 'foo', :path => tmp_path, :ensure => :absent, :match_for_absence => :true, :match => 'match') }.not_to raise_error
   end
+  it 'although if a line is specified anyway when matching for absence it still works and the line is silently ignored' do
+    expect { Puppet::Type.type(:file_line).new(:name => 'foo', :path => tmp_path, :line => 'i_am_irrelevant', :ensure => :absent, :match_for_absence => :true, :match => 'match') }.not_to raise_error
+  end
   it 'should require that a file is specified' do
     expect { Puppet::Type.type(:file_line).new(:name => 'foo', :line => 'path') }.to raise_error(Puppet::Error, /path is a required attribute/)
   end