use more modern functions if available

Author: scivision

+stdlib/get_permissions.m

@@ -13,16 +13,13 @@
   v = filePermissions(f);
 catch e
   switch e.identifier
-    case "MATLAB:io:filesystem:filePermissions:CannotFindLocation", return
+    case "MATLAB:UndefinedFunction", v = file_attributes_legacy(f);
     case "Octave:undefined-function"
       [s, err] = stat(f);
       if err == 0
         p = s.modestr;
       end
       return
-    case "MATLAB:UndefinedFunction"
-      v = file_attributes(f);
-      if isempty(v), return, end
     otherwise, rethrow(e)
   end
 end

+stdlib/is_exe.m

@@ -1,19 +1,28 @@
 %% IS_EXE is file executable
 %
-% false if file does not exist
+% false if not a file
 
 function ok = is_exe(p)
 arguments
   p {mustBeTextScalar}
 end
 
-a = file_attributes(p);
-
-ok = ~isempty(a) && (a.UserExecute || a.GroupExecute || a.OtherExecute);
+if ~isfile(p)
+  ok = false;
+  return
+end
 
+try
+  a = filePermissions(p);
+  ok = a.UserExecute || (isa(a, "matlab.io.UnixPermissions") && (a.GroupExecute || a.OtherExecute));
+catch e
+  switch e.identifier
+    case {'Octave:undefined-function', 'MATLAB:UndefinedFunction'}
+      a = file_attributes_legacy(p);
+      ok = ~isempty(a) && (a.UserExecute || a.GroupExecute || a.OtherExecute);
+    otherwise, rethrow(e)
+  end
 end
 
-%!assert (!is_exe(''))
-%!assert (!is_exe(tempname))
-%!assert (is_exe("."))
+%!assert (!is_exe("."))
 %!assert (is_exe(program_invocation_name))

+stdlib/is_readable.m

@@ -1,17 +1,20 @@
 %% IS_READABLE is file readable
-%
-% non-existant file is false
 
 function ok = is_readable(p)
 arguments
   p {mustBeTextScalar}
 end
 
-a = file_attributes(p);
-
-ok = ~isempty(a) && (a.UserRead || a.GroupRead || a.OtherRead);
-
+try
+  a = filePermissions(p);
+  ok = a.Readable || (isa(a, "matlab.io.UnixPermissions") && (a.GroupRead || a.OtherRead));
+catch e
+  switch e.identifier
+    case {'Octave:undefined-function', 'MATLAB:UndefinedFunction'}
+      a = file_attributes_legacy(p);
+      ok = ~isempty(a) && (a.UserRead || a.GroupRead || a.OtherRead);
+    otherwise, rethrow(e)
+  end
 end
 
 %!assert (is_readable('is_readable.m'))
-%!assert (!is_readable(''))

+stdlib/is_writable.m

@@ -1,17 +1,21 @@
 %% IS_WRITABLE is path writable
-%
-% non-existant path is false
 
 function ok = is_writable(p)
 arguments
   p {mustBeTextScalar}
 end
 
-a = file_attributes(p);
-
-ok = ~isempty(a) && (a.UserWrite || a.GroupWrite || a.OtherWrite);
-
+try
+  a = filePermissions(p);
+  ok = a.Writable || (isa(a, "matlab.io.UnixPermissions") && (a.GroupWrite || a.OtherWrite));
+catch e
+  switch e.identifier
+    case {'Octave:undefined-function', 'MATLAB:UndefinedFunction'}
+      a = file_attributes_legacy(p);
+      ok = ~isempty(a) && (a.UserWrite || a.GroupWrite || a.OtherWrite);
+    otherwise, rethrow(e)
+  end
 end
 
+end
 %!assert (is_writable('is_writable.m'))
-%!assert (!is_writable(''))

+stdlib/private/file_attributes.m renamed to +stdlib/private/file_attributes_legacy.m

@@ -1,21 +1,17 @@
-function a = file_attributes(p)
+function a = file_attributes_legacy(p)
 
-a = [];
+assert(~strempty(p), 'Path must not be empty.')
 
-if strempty(p), return, end
+[status, s] = fileattrib(p);
 
-[status, a] = fileattrib(p);
-if status ~= 1
-  % matlab puts the error message in the struct
-  a = [];
-  return
-end
+assert(status == 1, "'%s' is not a file or directory.", p);
 
+a = s;
 for n = {"GroupRead", "GroupWrite", "GroupExecute", "OtherRead", "OtherWrite", "OtherExecute"}
   name = n{1};
+
   if ~isfield(a, name) || isnan(a.(name))
     a.(name) = false;
   end
 end
-
 end

+stdlib/set_permissions.m

@@ -9,28 +9,23 @@
 %%% Outputs
 % * ok (1,1) logical
 
-function ok = set_permissions(path, readable, writable, executable)
+function set_permissions(path, readable, writable, executable)
 arguments
   path {mustBeTextScalar,mustBeFile}
   readable (1,1) int8
   writable (1,1) int8
   executable (1,1) int8
 end
 
-ok = false;
-
 try
   p = filePermissions(path);
 catch e
   switch e.identifier
     case "MATLAB:UndefinedFunction", error("buildtool mex")
-    case "MATLAB:io:filesystem:filePermissions:CannotFindLocation", return
     otherwise, rethrow(e)
   end
 end
 
-ok = true;
-
 if readable ~= 0
   setPermissions(p, "Readable", readable > 0);
 end

src/set_permissions.cpp

@@ -86,6 +86,9 @@ class MexFunction : public matlab::mex::Function {
 // https://www.mathworks.com/help/matlab/matlab_external/create-matlab-array-with-matlab-data-cpp-api.html
 // https://www.mathworks.com/help/matlab/apiref/matlab.data.arrayfactory.html
 
-    outputs[0] = factory.createScalar<bool>(y);
+    if (!y) {
+      matlabEng->feval(u"error", 0,
+        std::vector<matlab::data::Array>({ factory.createScalar("Mex: Failed to set permissions") }));
+    }
   }
 };

test/TestExists.m

@@ -2,8 +2,7 @@
 
 properties(TestParameter)
 Ps = {{pwd(), true}, {mfilename("fullpath") + ".m", true}, ...
-      {"TestFileImpure.m", true} {tempname(), false}, ...
-      {"", false}}
+      {"TestFileImpure.m", true}}
 % on CI matlabroot can be writable!
 end
 

test/TestFileImpure.m

@@ -1,7 +1,7 @@
 classdef TestFileImpure < matlab.unittest.TestCase
 
 properties(TestParameter)
-p_is_writable = {{pwd(), true}, {"not-exists", false}, {"", false}};
+p_is_writable = {{pwd(), true}};
 
 p_same = {...
 {"..", "./.."}, ...

test/TestIsExe.m

@@ -1,15 +1,15 @@
 classdef TestIsExe < matlab.unittest.TestCase
 
 properties (TestParameter)
-p = {{"", false}, {tempname(), false}, {".", true}}
+p = {{".", false}}
 end
 
 methods(Test, TestTags="impure")
 function test_is_exe(tc, p)
 tc.verifyEqual(stdlib.is_exe(p{1}), p{2})
 end
 
-function test_matlabroot(tc)
+function test_matlab_exe(tc)
 
 f = fullfile(matlabroot, "bin", "matlab");
 if ispc()