Added tests for mergeStructs (#177)

* added tests for mergeStructs

* fixed typo and added test for error

tests/testMergeStructs.m

@@ -0,0 +1,27 @@
+classdef testMergeStructs < matlab.unittest.TestCase   
+
+    properties (TestParameter)
+        s = {struct('s1', 1, 's2', 2),...
+             struct('s1', 1),...
+             struct('s1', 1, 's2', 2, 's3', 3)};
+        d = {struct('d1', 1, 'd2', 2),...
+             struct('d1', 1),...
+             struct('d1', 1, 'd2', 2)};
+        r = {struct('s1', 1, 's2', 2, 'd1', 1, 'd2', 2),...
+             struct('s1', 1, 'd1', 1),...
+             struct('s1', 1, 's2', 2, 's3', 3, 'd1', 1, 'd2', 2)};
+    end
+
+    methods (Test, ParameterCombination="sequential")
+        function testMergeResults(testCase, s, d, r)
+            result = mergeStructs(s, d);
+            testCase.verifyEqual(result, r);
+        end
+
+        function testMergeError(testCase)
+            s1 = struct('s', 1);
+            s2 = struct('s', 3);
+            testCase.verifyError(@() mergeStructs(s1, s2), 'MATLAB:DuplicateFieldName')
+        end
+    end
+end