touch: don't reset modtime if created file

set_modtime: require time input

Author: scivision

+stdlib/get_modtime.m

@@ -23,7 +23,6 @@
 
 %!test
 %! p = tempname();
-%! t = time();
-%! assert(touch(p, t))
+%! assert(touch(p, []))
 %! assert(get_modtime(p) > 0)
 %! delete(p)

+stdlib/set_modtime.m

@@ -3,7 +3,7 @@
 function ok = set_modtime(p, t)
 arguments
   p (1,1) string
-  t (1,1) datetime = datetime("now")
+  t (1,1) datetime
 end
 
 try
@@ -23,6 +23,6 @@
 %!test
 %! p = tempname();
 %! t = time()
-%! assert(touch(p, t))
+%! assert(touch(p, []))
 %! assert(set_modtime(p, t))
 %! delete(p)

+stdlib/touch.m

@@ -3,24 +3,34 @@
 function ok = touch(p, t)
 arguments
   p (1,1) string
-  t (1,1) datetime = datetime("now")
+  t datetime {mustBeScalarOrEmpty} = datetime.empty
 end
 
 ok = false;
 
 if ~stdlib.exists(p)
   fid = fopen(p, "w");
-  if fid < 0 || fclose(fid) ~= 0
+  ok = fid > 0 && fclose(fid) == 0;
+  if isempty(t)
     return
   end
 end
 
-ok = stdlib.set_modtime(p, t);
+if isempty(t)
+  t = datetime("now");
+end
+
+try
+  ok = stdlib.set_modtime(p, t);
+catch e
+  if ~strcmp(e.identifier, "MATLAB:undefinedVarOrClass")
+    rethrow(e)
+  end
+end
 
 end
 
 %!test
 %! f = tempname();
-%! t = time();
-%! assert (touch(f, t))
+%! assert (touch(f, []))
 %! assert (isfile(f))

test/TestJava.m

@@ -136,7 +136,7 @@ function test_touch_modtime(tc)
 tc.verifyTrue(stdlib.touch(fn, datetime("yesterday")))
 t0 = stdlib.get_modtime(fn);
 
-tc.verifyTrue(stdlib.set_modtime(fn))
+tc.verifyTrue(stdlib.set_modtime(fn, datetime("now")))
 t1 = stdlib.get_modtime(fn);
 
 tc.verifyGreaterThanOrEqual(t1, t0)
@@ -148,7 +148,7 @@ function test_get_modtime(tc)
 end
 
 function test_set_modtime(tc)
-tc.verifyEqual(stdlib.set_modtime(""), false)
+tc.verifyEqual(stdlib.set_modtime("", datetime("now")), false)
 end