[2/3] mesos git commit: Fixed 'operator==' for 'v1::Resource::DiskInfo::Source'.

[ji...@apache.org]

Fixed 'operator==' for 'v1::Resource::DiskInfo::Source'.

When implementing 'operator==' for protobufs as a pattern we typically
first check that two 'optional' fields are set for both the left- and
right-hand side, and only then compare their values, e.g., given a
definition

    message Foo {
      optional string bar = 1;
    }

we would implement 'operator==' similar to the following,

   bool operator==(const Foo& lhs, const Foo& rhs)
   {
       if (lhs.has_bar() != rhs.has_bar()) {
         return false;
       }

       if (lhs.has_bar() && lhs.bar() != rhs.bar()) {
         return false;
       }

       return true;
   }

One reason for this is that it allows us to distinguish an unset field
from a set field containing a default constructed value (if e.g.,
above 'lhs.has_bar()' was 'false', 'lhs.bar()' would return an empty
string).

This patch makes sure we use the same pattern when checking
'v1::Resource::DiskInfo::Source' for equality. An earlier patch
('591f74d') already fixed this for 'Resources::DiskInfo::Source'.

Review: https://reviews.apache.org/r/62842/


Project: http://git-wip-us.apache.org/repos/asf/mesos/repo
Commit: http://git-wip-us.apache.org/repos/asf/mesos/commit/52079854
Tree: http://git-wip-us.apache.org/repos/asf/mesos/tree/52079854
Diff: http://git-wip-us.apache.org/repos/asf/mesos/diff/52079854

Branch: refs/heads/master
Commit: 5207985400a9135f85f9340bd679cc7d12ebec4d
Parents: 07f8da2
Author: Benjamin Bannier <bb...@apache.org>
Authored: Mon Oct 9 14:30:39 2017 -0700
Committer: Jie Yu <yu...@gmail.com>
Committed: Mon Oct 9 14:45:05 2017 -0700

----------------------------------------------------------------------
 src/v1/resources.cpp | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)
----------------------------------------------------------------------


http://git-wip-us.apache.org/repos/asf/mesos/blob/52079854/src/v1/resources.cpp
----------------------------------------------------------------------
diff --git a/src/v1/resources.cpp b/src/v1/resources.cpp
index a64180b..04df4d4 100644
--- a/src/v1/resources.cpp
+++ b/src/v1/resources.cpp
@@ -174,18 +174,34 @@ bool operator==(
     return false;
   }
 
+  if (left.has_path() != right.has_path()) {
+    return false;
+  }
+
   if (left.has_path() && left.path() != right.path()) {
     return false;
   }
 
+  if (left.has_mount() != right.has_mount()) {
+    return false;
+  }
+
   if (left.has_mount() && left.mount() != right.mount()) {
     return false;
   }
 
+  if (left.has_id() != right.has_id()) {
+    return false;
+  }
+
   if (left.has_id() && left.id() != right.id()) {
     return false;
   }
 
+  if (left.has_metadata() != right.has_metadata()) {
+    return false;
+  }
+
   if (left.has_metadata() && left.metadata() != right.metadata()) {
     return false;
   }