which: more robust, add tests

Author: scivision

+stdlib/which.m

@@ -9,36 +9,46 @@
 
 function exe = which(filename, fpath, find_all)
 arguments
-  filename (1,1) string
+  filename {mustBeTextScalar}
   fpath (1,:) string = string.empty
   find_all (1,1) logical = false
 end
 
-exe = string.empty;
+if find_all
+  exe = string.empty;
+else
+  exe = '';
+end
 
 if isfile(filename) && stdlib.is_exe(filename)
   exe = filename;
   return
 end
 
 %  relative directory component, but path was not a file
-if stdlib.filename(filename) ~= filename
+if ~strcmp(stdlib.filename(filename), filename)
   return
 end
 
 % path given
 if isempty(fpath)
-  fpath = string(getenv("PATH"));
+  fpath = getenv("PATH");
 end
 
-if isscalar(fpath)
-  fpath = split(fpath, pathsep).';
+if isscalar(fpath) || ischar(fpath)
+  fpath = strsplit(fpath, pathsep);
 end
 
-for p = fpath
+for fp = fpath
+  if iscell(fp)
+    p = fp{1};
+  else
+    p = fp;
+  end
+
   if ~strlength(p), continue, end
 
-  e = p + "/" + filename;
+  e = strcat(p, '/', filename);
   if isfile(e) && stdlib.is_exe(e)
     if find_all
       exe(end+1) = e; %#ok<AGROW>
@@ -51,4 +61,4 @@
 
 end
 
-%!testif 0
+%!assert(~isempty(which("octave", [], false)))

test/TestWhich.m

@@ -1,15 +1,20 @@
 classdef TestWhich < matlab.unittest.TestCase
 
+properties (TestParameter)
+mexe = {matlabroot + "/bin/" + matlab_name(), ...
+        fullfile(matlabroot, 'bin', matlab_name())}
+end
+
 methods (Test)
 
 function test_which_name(tc)
 
 tc.verifyEmpty(stdlib.which(tempname()))
 
 if ispc
-  n = "pwsh.exe";
+  n = 'pwsh.exe';
 else
-  n = "ls";
+  n = 'ls';
 end
 %% which: Matlab in environment variable PATH
 % MacOS Matlab does not source .zshrc so Matlab is not on internal Matlab PATH
@@ -21,34 +26,16 @@ function test_which_name(tc)
 end
 
 
-function test_which_fullpath(tc)
-import matlab.unittest.constraints.IsFile
-import matlab.unittest.constraints.EndsWithSubstring
-
-%% is_exe test
-p = matlabroot + "/bin/" + matlab_name();
-
-tc.assumeTrue(stdlib.is_exe(p), "Matlab not executable " + p)
-%% which: test absolute path
-exe = stdlib.which(p);
-
-tc.verifyNotEmpty(exe, "Matlab not found " + p)
-
-if ispc
-  tc.verifyThat(exe, EndsWithSubstring(".exe"))
-else
-  tc.verifyThat(exe, ~EndsWithSubstring(".exe"))
+function test_which_absolute(tc, mexe)
+tc.verifyEqual(stdlib.which(mexe), mexe)
 end
-tc.verifyThat(exe, IsFile)
 
-end
 
 function test_which_multipath(tc)
 
 n = matlab_name();
 
-paths = string(getenv("PATH"));
-paths = split(paths, pathsep);
+paths = split(string(getenv('PATH')), pathsep);
 paths(end+1) = matlabroot + "/bin";
 
 exe = stdlib.which(n, paths);
@@ -64,8 +51,8 @@ function test_which_multipath(tc)
 
 function n = matlab_name()
 
-n = "matlab";
+n = 'matlab';
 if ispc
-  n = n + ".exe";
+  n = strcat(n, '.exe');
 end
 end