[c++/m] Add Block compare function

Add compare function to the c++ side and
a corresponding test on the matlab side.

Author: mpsonntag

nix_mx.cc

@@ -165,6 +165,7 @@ void mexFunction(int            nlhs,
         methods->add("Block::openTagIdx", nixblock::openTagIdx);
         methods->add("Block::openMultiTagIdx", nixblock::openMultiTagIdx);
         methods->add("Block::openSourceIdx", nixblock::openSourceIdx);
+        methods->add("Block::compare", nixblock::compare);
 
         classdef<nix::Group>("Group", methods)
             .desc(&nixgroup::describe)

src/nixblock.cc

@@ -90,4 +90,10 @@ namespace nixblock {
         output.set(0, currObj.getSource(idx));
     }
 
+    void compare(const extractor &input, infusor &output) {
+        nix::Block currObj = input.entity<nix::Block>(1);
+        nix::Block other = input.entity<nix::Block>(2);
+        output.set(0, currObj.compare(other));
+    }
+
 } // namespace nixblock

src/nixblock.h

@@ -31,6 +31,8 @@ namespace nixblock {
 
     void openSourceIdx(const extractor &input, infusor &output);
 
+    void compare(const extractor &input, infusor &output);
+
 } // namespace nixblock
 
 #endif

tests/TestBlock.m

@@ -49,6 +49,7 @@
     funcs{end+1} = @test_tag_count;
     funcs{end+1} = @test_multi_tag_count;
     funcs{end+1} = @test_source_count;
+    funcs{end+1} = @test_compare;
 end
 
 function [] = test_attrs( varargin )
@@ -741,3 +742,14 @@
     f = nix.File(testFile, nix.FileMode.ReadOnly);
     assert(f.blocks{1}.source_count() == 2);
 end
+
+function [] = test_compare( varargin )
+%% Test: Compare block entities
+    f = nix.File(fullfile(pwd, 'tests', 'testRW.h5'), nix.FileMode.Overwrite);
+    b1 = f.create_block('testBlock1', 'nixBlock');
+    b2 = f.create_block('testBlock2', 'nixBlock');
+
+    assert(b1.compare(b2) < 0);
+    assert(b1.compare(b1) == 0);
+    assert(b2.compare(b1) > 0);
+end