toolbox_used: protect from spurious OpenMP error when parallel toolbox is installed

Author: scivision

+stdlib/toolbox_used.m

@@ -1,14 +1,56 @@
 %% TOOLBOX_USED list all Matlab toolboxes used by all functions in pkgPath
 %
 %%% inputs
-% * pkgPath: path to user namespace or file. Example: '+stdlib' or 'stdlib.cpu_arch'
+% * pkgPath: path to user namespace or file. Example: 'stdlib' or 'stdlib.cpu_arch'
 %%% Outputs
 % * tbxMathworks: Mathworks toolbox names used
 % * funUser: all user function files under pkgPath
 
-function [tbxMathworks, funUser] = toolbox_used(pkgPath)
+function [tbxMathworks, funUser] = toolbox_used(name)
 
-[user, mathworks] = matlab.codetools.requiredFilesAndProducts(pkgPath);
+n = name;
+
+try
+
+  f = namespaceFunctions(name);
+  if ~isempty(f)
+    n = f(1).NamespaceName + "." + string({f.Name});
+  end
+
+catch e
+
+  if ~strcmp(e.identifier, 'MATLAB:UndefinedFunction')
+    rethrow(e)
+  end
+
+end
+
+if ispc()
+  old = getenv('KMP_DUPLICATE_LIB_OK');
+  setenv('KMP_DUPLICATE_LIB_OK', 'TRUE');
+
+  % otherwise,
+  %   matlab -batch "buildtool test"
+  % or
+  %   matlab -batch "stdlib.toolbox_used('stdlib')"
+  % crash Matlab with:
+  %   OMP: Error #15: Initializing libiomp5md.dll, but found libiomp5md.dll already initialized.
+  %
+  % calling toolbox_used on any one function doesn't fail.
+end
+
+try
+  [user, mathworks] = matlab.codetools.requiredFilesAndProducts(n);
+catch e
+  if ispc()
+    setenv('KMP_DUPLICATE_LIB_OK', old)
+  end
+  rethrow(e)
+end
+
+if ispc()
+  setenv('KMP_DUPLICATE_LIB_OK', old)
+end
 
 tbxMathworks = string({mathworks.Name}).';
 

test/TestPlatform.m

@@ -31,15 +31,16 @@ function test_has_parallel_toolbox(tc)
 
 function test_toolbox_used(tc)
 tc.assumeFalse(stdlib.matlabOlderThan('R2018a'))
-r = fullfile(fileparts(fileparts(mfilename('fullpath'))), '+stdlib');
-[mathworksUsed, userFun] = stdlib.toolbox_used(r);
+
+[mathworksUsed, userFun] = stdlib.toolbox_used('stdlib');
+
 Nlicense = length(mathworksUsed);
 tc.verifyGreaterThanOrEqual(Nlicense, 1)
 tc.verifyTrue(ismember('MATLAB', mathworksUsed))
 tc.verifyGreaterThan(length(userFun), 200) % we have over 200 stdlib functions
 
 % don't use paid toolboxes without checking they exist, otherwise this function fails
-[mathworksUsed, userFun] = stdlib.toolbox_used(["which", "disp"]);
+[mathworksUsed, userFun] = stdlib.toolbox_used('disp');
 tc.verifyEqual(userFun, string.empty)
 tc.verifyEqual(length(mathworksUsed), 1)
 end