is_exe: native only: fast enough

Author: scivision

+stdlib/+java/is_exe.m

@@ -1,12 +1,15 @@
 function y = is_exe(file)
+arguments
+  file (1,1) string
+end
 
-y = isfile(file);
+y = false;
 
-if ispc()
-  y = y && stdlib.native.has_windows_executable_suffix(file);
+if ispc() && ~stdlib.native.has_windows_executable_suffix(file)
+  return
 end
 
-if ~y, return, end
+if ~isfile(file), return, end
 
 a = file_attributes(file);
 y = a.UserExecute || a.GroupExecute || a.OtherExecute;

+stdlib/+legacy/is_exe.m

@@ -5,21 +5,16 @@
 % file: path to check
 %% Outputs
 % ok: true if path is a file and has executable permissions
-% b: backend used
 
-function [ok, b] = is_exe(file, backend)
+function ok = is_exe(file)
 arguments
   file string
-  backend (1,:) string = ["java", "python", "native", "legacy"]
 end
 
-% Java or Python ~ 100x faster than Matlab native
-[fun, b] = hbackend(backend, "is_exe");
-
-if isscalar(file) || b == "native"
-  ok = fun(file);
+if isscalar(file)
+  ok = stdlib.legacy.is_exe(file);
 else
-  ok = arrayfun(fun, file);
+  ok = stdlib.native.is_exe(file);
 end
 
 end

+stdlib/is_exe.m

@@ -1,12 +1,11 @@
-%% IS_EXE is file executable
+function y = is_exe(p)
 
-function ok = is_exe(p)
+y = isfile(p);
 
-% about the same time as fileattrib
-% https://docs.oracle.com/en/java/javase/22/docs/api/java.base/java/io/File.html#canExecute()
-% more complicated
-% ok = java.nio.file.Files.isExecutable(javaPathObject(stdlib.canonical(p)));
+if ispc()
+  y = y && stdlib.native.has_windows_executable_suffix(p);
+end
 
-ok = javaFileObject(p).canExecute();
+y = y && java.io.File(p).canExecute();
 
-end
+end

example/+javafun/is_exe.m

@@ -8,15 +8,15 @@ function bench_is_exe()
 ff = @() stdlib.is_exe(in);
 fn = @() stdlib.native.is_exe(in);
 fl = @() stdlib.legacy.is_exe(in);
-fj = @() stdlib.java.is_exe(in);
-fp = @() stdlib.python.is_exe(in);
+fj = @() javafun.is_exe(in);
+fp = @() python.is_exe(in);
 
 tj = timeit(fj) * 1e3;
-tp = timeit(fp) * 1e3;
+tl = timeit(fl) * 1e3;
 tf = timeit(ff) * 1e3;
 tn = timeit(fn) * 1e3;
-tl = timeit(fl) * 1e3;
+tp = timeit(fp) * 1e3;
 
-fprintf('Full: %f\nNative: %f\nLegacy: %f\nJava: %f\nPython: %f\n', tf, tl, tn, tj, tp);
+fprintf('Full %f\nNative: %f\nLegacy: %f\nJava: %f\nPython: %f\n', tf, tn, tl, tj, tp);
 
 end

+stdlib/+python/is_exe.m renamed to example/+python/is_exe.m

@@ -12,7 +12,6 @@
 {matlab_path(), true}
 }
 peb = init_exe_bin()
-backend = init_backend({'java', 'python', 'native', 'legacy'}, 'native', ~isMATLABReleaseOlderThan('R2025a'))
 end
 
 methods(TestClassSetup)
@@ -25,18 +24,24 @@ function test_dirs(tc)
 
 methods(Test)
 
-function test_is_exe(tc, p, backend)
-r = stdlib.is_exe(p{1}, backend);
+function test_is_exe(tc, p)
+r = stdlib.is_exe(p{1});
+tc.verifyEqual(r, p{2})
+end
+
+function test_is_exe_legacy(tc, p)
+r = stdlib.legacy.is_exe(p{1});
 tc.verifyEqual(r, p{2})
 end
 
 
-function test_is_exe_array(tc, backend)
+function test_is_exe_array(tc)
+tc.assumeFalse(isMATLABReleaseOlderThan('R2025a'))
 n = fullfile(matlabroot, "bin/matlab");
 if ispc()
   n = n + ".exe";
 end
-r = stdlib.is_exe(["Readme.md", tempname(), n], backend);
+r = stdlib.is_exe(["Readme.md", tempname(), n]);
 tc.verifyEqual(r, [false, false, true])
 end