(FACT-2805) Add Cached and Buffers to memfree

Facter 3 adds cached and buffers to memfree fact. This makes sure we are consistent with what facter 3 displays

Author: florindragos

lib/facter/resolvers/memory_resolver.rb

@@ -25,11 +25,17 @@ def read_meminfo_file(fact_name)
 
           def read_system(output)
             @fact_list[:total] = kilobytes_to_bytes(output.match(/MemTotal:\s+(\d+)\s/)[1])
-            @fact_list[:memfree] = kilobytes_to_bytes(output.match(/MemFree:\s+(\d+)\s/)[1])
+            @fact_list[:memfree] = memfree(output)
             @fact_list[:used_bytes] = compute_used(@fact_list[:total], reclaimable_memory(output))
             @fact_list[:capacity] = compute_capacity(@fact_list[:used_bytes], @fact_list[:total])
           end
 
+          def memfree(output)
+            buffers = kilobytes_to_bytes(output.match(/Buffers:\s+(\d+)\s/)[1])
+            cached = kilobytes_to_bytes(output.match(/Cached:\s+(\d+)\s/)[1])
+            kilobytes_to_bytes(output.match(/MemFree:\s+(\d+)\s/)[1]) + buffers + cached
+          end
+
           def read_swap(output)
             total = output.match(/SwapTotal:\s+(\d+)\s/)[1]
             return if total.to_i.zero?
@@ -45,15 +51,13 @@ def kilobytes_to_bytes(quantity)
           end
 
           def reclaimable_memory(output)
-            buffers = kilobytes_to_bytes(output.match(/Buffers:\s+(\d+)\s/)[1])
-            cached = kilobytes_to_bytes(output.match(/Cached:\s+(\d+)\s/)[1])
             s_reclaimable = output.match(/SReclaimable:\s+(\d+)\s/)
             s_reclaimable = if s_reclaimable
                               kilobytes_to_bytes(s_reclaimable[1])
                             else
                               0
                             end
-            @fact_list[:memfree] + buffers + cached + s_reclaimable
+            @fact_list[:memfree] + s_reclaimable
           end
 
           def compute_capacity(used, total)

spec/facter/resolvers/memory_resolver_spec.rb

@@ -16,11 +16,11 @@
 
     context 'when there is swap memory' do
       let(:total) { 4_036_680 * 1024 }
-      let(:free) { 3_547_792 * 1024 }
       let(:buffers) { 4_288 * 1024 }
       let(:cached) { 298_624 * 1024 }
+      let(:free) { (3_547_792 * 1024) + buffers + cached }
       let(:s_reclaimable) { 29_072 * 1024 }
-      let(:used) { total - free - buffers - cached - s_reclaimable }
+      let(:used) { total - free - s_reclaimable }
       let(:swap_total) { 2_097_148 * 1024 }
       let(:swap_free) { 2_097_148 * 1024 }
       let(:swap_used) { swap_total - swap_free }
@@ -65,11 +65,11 @@
 
     context 'when there is not swap memory' do
       let(:total) { 4_134_510_592 }
-      let(:free) { 3_465_723_904 }
       let(:buffers) { 2_088 * 1024 }
       let(:cached) { 445_204 * 1024 }
+      let(:free) { 3_465_723_904 + buffers + cached }
       let(:s_reclaimable) { 71_384 * 1024 }
-      let(:used) { total - free - buffers - cached - s_reclaimable }
+      let(:used) { total - free - s_reclaimable }
       let(:fixture_name) { 'meminfo2' }
 
       it 'returns total memory' do
@@ -109,11 +109,11 @@
 
     context 'when on Rhel 5' do
       let(:total) { 4_036_680 * 1024 }
-      let(:free) { 3_547_792 * 1024 }
       let(:buffers) { 4_288 * 1024 }
       let(:cached) { 298_624 * 1024 }
+      let(:free) { (3_547_792 * 1024) + buffers + cached }
       let(:s_reclaimable) { 0 }
-      let(:used) { total - free - buffers - cached - s_reclaimable }
+      let(:used) { total - free - s_reclaimable }
       let(:swap_total) { 2_097_148 * 1024 }
       let(:swap_free) { 2_097_148 * 1024 }
       let(:swap_used) { swap_total - swap_free }