# HG changeset patch
# User Pantxo Diribarne <pantxo.diribarne@gmail.com>
# Date 1382300611 -7200
# Node ID 9ccb48d39ce9dc629b814a119fa6ff434e18b508
# Parent  3dec0a57ab55a47ded7217878ab4b367a188e3c3
run.m: append .m extension when none was provided.
Also, look for file in path if it is not in pwd.

* scripts/miscellaneous/run.m: Redo docstring.  Test early for missing '.m'
extension and use exist to search load path.  Use which to check for script
in load path.

diff -r 3dec0a57ab55 -r 9ccb48d39ce9 scripts/miscellaneous/run.m
--- a/scripts/miscellaneous/run.m	Fri Apr 12 20:10:32 2013 +0100
+++ b/scripts/miscellaneous/run.m	Sun Oct 20 22:23:31 2013 +0200
@@ -18,13 +18,23 @@
 
 ## -*- texinfo -*-
 ## @deftypefn  {Command} {} run @var{script}
-## @deftypefnx {Function File} {} run (@var{script})
-## Run scripts in the current workspace that are not necessarily on the
-## path.  If @var{script} is the script to run, including its path, then
-## @code{run} changes the directory to the directory where @var{script} is
-## found.  @code{run} then executes the script, and returns to the original
-## directory.
-## @seealso{system}
+## @deftypefnx {Function File} {} run ("@var{script}")
+## Run @var{script} in the current workspace.
+##
+## Scripts which reside in directories specified in Octave's load
+## path, and which end with the extension @file{".m"}, can be run simply by
+## typing their name.  For scripts not located on the load path, use @code{run}.
+##
+## The file name @var{script} can be a bare, fully qualified, or relative
+## filename and with or without a file extension.  If no extension is specified,
+## Octave will first search for a script with the @file{".m"} extension before
+## falling back to the script name without an extension.
+##
+## Implementation Note: If @var{script} includes a path component, then
+## @code{run} first changes the directory to the directory where @var{script}
+## is found.  @code{run} then executes the script, and returns to the original
+## directory. 
+## @seealso{path, addpath, source}
 ## @end deftypefn
 
 function run (script)
@@ -34,15 +44,25 @@
   endif
 
   [d, f, ext] = fileparts (script);
+  if (! strcmp (ext, ".m"))
+    ## prefer files with .m extension for compatibility with Matlab
+    if (exist ([script ".m"], "file"))
+      f = [f ext];
+      ext = ".m";
+      script = [script ".m"];
+    endif
+  endif
+  
+  if (! exist (script, "file"))
+    error ("run: file SCRIPT must exist and be a valid Octave scriptfile");
+  endif
+  
   if (! isempty (d))
     if (exist (d, "dir"))
       wd = pwd ();
       unwind_protect
         cd (d);
-        if (! exist ([f ext], "file"))
-          error ("run: file SCRIPT must exist and be a valid Octave scriptfile");
-        endif
-        evalin ("caller", sprintf ("source (\"%s%s\");", f, ext),
+        evalin ("caller", sprintf ('source ("%s%s");', f, ext),
                 "rethrow (lasterror ())");
       unwind_protect_cleanup
         cd (wd);
@@ -51,12 +71,20 @@
       error ("run: the path %s doesn't exist", d);
     endif
   else
-    if (exist (script, "file"))
-      evalin ("caller", sprintf ("source (\"%s\");", script),
-              "rethrow (lasterror ())");
+    if (! isempty (ext))
+      script = which (script);
     else
-      error ("run: %s not found", script);
+      ## Search PATH with null extension ('.' will be stripped and ext = "")
+      script = which ([script "."]);
     endif
+    evalin ("caller", sprintf ('source ("%s");', script),
+            "rethrow (lasterror ())");
   endif
 endfunction
 
+
+%% Test input validation
+%!error run ()
+%!error run ("a", "b")
+%!error <SCRIPT must exist> run ("__A_very_#unlikely#_file_name__")
+