[c++/m] add compare Property function

Author: mpsonntag

+nix/Property.m

@@ -65,6 +65,16 @@
         function [] = values_delete(obj)
             nix_mx('Property::deleteValues', obj.nix_handle);
         end
+        
+        % return value 0 means name and id of two properties are
+        % identical, any other value means either name or id differ.
+        function cmp_val = compare(obj, property)
+            if (~strcmp(class(property), class(obj)))
+               error('Function only supports comparison of Properties.');
+            end
+            cmp_val = nix_mx('Property::compare', obj.nix_handle, property.nix_handle);
+        end
+
     end
 
 end

nix_mx.cc

@@ -367,6 +367,7 @@ void mexFunction(int            nlhs,
         methods->add("Property::values", nixproperty::values);
         methods->add("Property::updateValues", nixproperty::updateValues);
         methods->add("Property::deleteValues", nixproperty::deleteValues);
+        methods->add("Property::compare", nixproperty::compare);
 
         classdef<nix::SetDimension>("SetDimension", methods)
             .desc(&nixdimensions::describe)

src/nixproperty.cc

@@ -69,4 +69,10 @@ namespace nixproperty {
         prop.deleteValues();
     }
 
+    void compare(const extractor &input, infusor &output) {
+        nix::Property pm = input.entity<nix::Property>(1);
+        nix::Property pc = input.entity<nix::Property>(2);
+        output.set(0, pm.compare(pc));
+    }
+
 } // namespace nixproperty

src/nixproperty.h

@@ -21,6 +21,8 @@ namespace nixproperty {
 
     void deleteValues(const extractor &input, infusor &output);
 
+    void compare(const extractor &input, infusor &output);
+
 } // namespace nixproperty
 
 #endif

tests/TestProperty.m

@@ -16,6 +16,7 @@
     funcs{end+1} = @test_values;
     funcs{end+1} = @test_value_count;
     funcs{end+1} = @test_values_delete;
+    funcs{end+1} = @test_property_compare;
 end
 
 %% Test: Access Attributes
@@ -145,3 +146,27 @@
     f = nix.File(testFile, nix.FileMode.ReadOnly);
     assert(isempty(f.sections{1}.allProperties{1}.values));
 end
+
+%% Test: Compare properties
+function [] = test_property_compare( varargin )
+    testFile = fullfile(pwd,'tests','testRW.h5');
+    f = nix.File(testFile, nix.FileMode.Overwrite);
+    s1 = f.create_section('testSection1', 'nixSection');
+    s2 = f.create_section('testSection2', 'nixSection');
+
+    p = s1.create_property_with_value('property', {true, false, true});
+
+    % test invalid property comparison
+    try
+        p.compare('I shall crash and burn');
+    catch ME
+        assert(strcmp(ME.message, 'Function only supports comparison of Properties.'));
+    end
+    
+    % test property equal comparison
+    assert(~p.compare(p));
+
+    % test property not eqal
+    pNEq = s2.create_property_with_value('property', {true, false});
+    assert(p.compare(pNEq)~=0);
+end