## Copyright (C) 2005-2013 Paul Kienzle
##
## This file is part of Octave.
##
## Octave is free software; you can redistribute it and/or modify it
## under the terms of the GNU General Public License as published by
## the Free Software Foundation; either version 3 of the License, or (at
## your option) any later version.
##
## Octave is distributed in the hope that it will be useful, but
## WITHOUT ANY WARRANTY; without even the implied warranty of
## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
## General Public License for more details.
##
## You should have received a copy of the GNU General Public License
## along with Octave; see the file COPYING.  If not, see
## <http://www.gnu.org/licenses/>.

## -*- texinfo -*-
## @deftypefn  {Command} {} test @var{name}
## @deftypefnx {Command} {} test @var{name} quiet|normal|verbose
## @deftypefnx {Function File} {} test ("@var{name}", "quiet|normal|verbose", @var{fid})
## @deftypefnx {Function File} {} test ("@var{name}", "quiet|normal|verbose", @var{fname})
## @deftypefnx {Function File} {@var{success} =} test (@dots{})
## @deftypefnx {Function File} {[@var{n}, @var{nmax}, @var{nxfail}, @var{nskip}] =} test (@dots{})
## @deftypefnx {Function File} {[@var{code}, @var{idx}] =} test ("@var{name}", "grabdemo")
## @deftypefnx {Function File} {} test ([], "explain", @var{fid})
## @deftypefnx {Function File} {} test ([], "explain", @var{fname})
##
## Perform built-in self-tests from the first file in the loadpath matching
## @var{name}.
##
## @code{test} can be called in either command or functional form.  The exact
## operation of test is determined by a combination of mode (interactive or
## batch), reporting level ("quiet", "normal", "verbose"), and whether a
## logfile or summary output variable is used.
##
## The default mode when @code{test} is called from the command line is
## interactive.  In this mode, tests will be run until the first error is
## encountered, or all tests complete successfully.  In batch mode, all tests
## are run regardless of any failures, and the results are collected for
## reporting.  Tests which require user interaction, i.e., demo blocks,
## are never run in batch mode.
##
## Batch mode is enabled by either 1) specifying a logfile using the third
## argument @var{fname} or @var{fid}, or 2) requesting an output argument
## such as @var{success}, @var{n}, etc.
##
## The optional second argument determines the amount of output to generate and
## which types of tests to run.  The default value is @qcode{"normal"}. 
## Requesting an output argument will suppress printing the final summary
## message and any intermediate warnings, unless verbose reporting is
## enabled.
##
## @table @asis
## @item @qcode{"quiet"}
## Print a summary message when all tests pass, or print an error with the
## results of the first bad test when a failure occurs.  Don't run tests which
## require user interaction.
##
## @item @qcode{"normal"}
## Display warning messages about skipped tests or failing xtests during test
## execution.
## Print a summary message when all tests pass, or print an error with the
## results of the first bad test when a failure occurs.  Don't run tests which
## require user interaction.
##
## @item @qcode{"verbose"}
## Display tests before execution.  Print all warning messages.  In interactive
## mode, run all tests including those which require user interaction.
## @end table
##
## The optional third input argument specifies a logfile where results of the
## tests should be written.  The logfile may be a character string
## (@var{fname}) or an open file descriptor ID (@var{fid}).  To enable batch
## processing, but still print the results to the screen, use @code{stdout} for
## @var{fid}.
##
## When called with just a single output argument @var{success}, @code{test}
## returns true if all of the tests were successful.  If called with more
## than one output argument then the number of successful tests (@var{n}),
## the total number of tests in the file (@var{nmax}), the number of xtest
## failures (@var{nxfail}), and the number of skipped tests (@var{nskip} are
## returned.
##
## Example
##
## @example
## @group
## test sind
## @result{}
## PASSES 5 out of 5 tests
##
## [n, nmax] = test ("sind")
## @result{}
## n =  5
## nmax =  5
## @end group
## @end example
## 
## Additional Calling Syntaxes
##
## If the second argument is the string @qcode{"grabdemo"}, the contents of
## any built-in demo blocks are extracted but not executed.  The text for all
## code blocks is concatenated and returned as @var{code} with @var{idx} being
## a vector of positions of the ends of each demo block.  For an easier way to
## extract demo blocks from files, @xref{XREFexample,,example}.
##
## If the second argument is @qcode{"explain"} then @var{name} is ignored and
## an explanation of the line markers used in @code{test} output reports is
## written to the file specified by @var{fname} or @var{fid}.
##
## @seealso{assert, fail, demo, example, error}
## @end deftypefn

## Programming Note: All variables for test() must use the internal prefix "__".
## Shared variables are eval'ed into the current workspace and therefore might
## collide with the names used in the test.m function itself.

function [__n, __nmax, __nxfail, __nskip] = test (__name, __flag = "normal", __fid = [])

  ## Output from test is prefixed by a "key" to quickly understand the issue.
  persistent __signal_fail  = "!!!!! ";
  persistent __signal_empty = "????? ";
  persistent __signal_block = "***** ";
  persistent __signal_file  = ">>>>> ";
  persistent __signal_skip  = "----- ";

  if (nargin < 1 || nargin > 3)
    print_usage ();
  elseif (! isempty (__name) && ! ischar (__name))
    error ("test: NAME must be a string");
  elseif (! ischar (__flag))
    error ("test: second argument must be a string");
  elseif (isempty (__name) && (nargin != 3 || ! strcmp (__flag, "explain")))
    print_usage ();
  endif

  ## Decide if error messages should be collected.
  __logfile = ! isempty (__fid);
  __batch = __logfile || nargout > 0;
  __close_fid = false;
  if (__logfile)
    if (ischar (__fid))
      __fname = __fid;
      __fid = fopen (__fname, "wt");
      if (__fid < 0)
        error ("test: could not open log file %s", __fname);
      endif
      __close_fid = true;
    endif
    if (! strcmp (__flag, "explain"))
      fprintf (__fid, "%sprocessing %s\n", __signal_file, __name);
      fflush (__fid);
    endif
  else
    __fid = stdout;
  endif

  if (strcmp (__flag, "normal"))
    __grabdemo = false;
    __rundemo  = false;
    if (__logfile)
      __verbose = 1;
    elseif (__batch)
      __verbose = -1;
    else
      __verbose = 0;
    endif
  elseif (strcmp (__flag, "quiet"))
    __grabdemo = false;
    __rundemo  = false;
    __verbose  = -1;
  elseif (strcmp (__flag, "verbose"))
    __grabdemo = false;
    __rundemo  = true;
    __verbose  = 1;
  elseif (strcmp (__flag, "grabdemo"))
    __grabdemo = true;
    __rundemo  = false;
    __verbose  = -1;
    __demo_code = "";
    __demo_idx = [];
  elseif (strcmp (__flag, "explain"))
    fprintf (__fid, "# %s new test file\n", __signal_file);
    fprintf (__fid, "# %s no tests in file\n", __signal_empty);
    fprintf (__fid, "# %s test had an unexpected result\n", __signal_fail);
    fprintf (__fid, "# %s test was skipped\n", __signal_skip);
    fprintf (__fid, "# %s code for the test\n\n", __signal_block);
    fprintf (__fid, "# Search for the unexpected results in the file\n");
    fprintf (__fid, "# then page back to find the file name which caused it.\n");
    fprintf (__fid, "# The result may be an unexpected failure (in which\n");
    fprintf (__fid, "# case an error will be reported) or an unexpected\n");
    fprintf (__fid, "# success (in which case no error will be reported).\n");
    fflush (__fid);
    if (__close_fid)
      fclose (__fid);
    endif
    return;
  else
    error ("test: unknown flag '%s'", __flag);
  endif

  ## Locate the file to test.
  __file = file_in_loadpath (__name, "all");
  if (isempty (__file))
    __file = file_in_loadpath ([__name ".m"], "all");
  endif
  if (isempty (__file))
    __file = file_in_loadpath ([__name ".cc"], "all");
  endif
  if (iscell (__file))
    if (isempty (__file))
      __file = "";
    else
      __file = __file{1};  # If repeats, return first in path.
    endif
  endif
  if (isempty (__file))
    if (__grabdemo)
      __n = "";
      __nmax = -1;
    else
      ftype = exist (__name);
      if (ftype == 3)
        fprintf (__fid, "%s%s source code with tests for dynamically linked function not found\n", __signal_empty, __name);
      elseif (ftype == 5)
        fprintf (__fid, "%s%s is a built-in function\n", __signal_empty, __name);
      elseif (any (strcmp (__operators__ (), __name)))
        fprintf (__fid, "%s%s is an operator\n", __signal_empty, __name);
      elseif (any (strcmp (__keywords__ (), __name)))
        fprintf (__fid, "%s%s is a keyword\n", __signal_empty, __name);
      else
        fprintf (__fid, "%s%s does not exist in path\n", __signal_empty, __name);
      endif
      fflush (__fid);
      if (nargout > 0)
        if (nargout == 1)
          __n = false;
        else
          __n = __nmax = 0;
        endif
      endif
    endif
    if (__close_fid)
      fclose (__fid);
    endif
    return;
  endif

  ## Grab the test code from the file.
  __body = __extract_test_code (__file);

  if (isempty (__body))
    if (__grabdemo)
      __n = "";
      __nmax = [];
    else
      fprintf (__fid, "%s%s has no tests available\n", __signal_empty, __file);
      fflush (__fid);
      if (nargout > 0)
        if (nargout == 1)
          __n = false;
        else
          __n = __nmax = 0;
        endif
      endif
    endif
    if (__close_fid)
      fclose (__fid);
    endif
    return;
  else
    ## Add a dummy comment block to the end for ease of indexing.
    if (__body(end) == "\n")
      __body = ["\n" __body "#"];
    else
      __body = ["\n" __body "\n#"];
    endif
  endif

  ## Chop it up into blocks for evaluation.
  __lineidx = find (__body == "\n");
  __blockidx = __lineidx(find (! isspace (__body(__lineidx+1))))+1;

  ## Ready to start tests.
  ## If in batch mode, with a logfile, report what is happening.
  if (__verbose > 0)
    disp ([__signal_file, __file]);
  endif

  ## Assume all tests will pass.
  __all_success = true;

  ## Process each block separately, initially with no shared variables.
  __tests = __successes = 0;
  __xfail = __xskip = 0;
  __shared = " ";
  __shared_r = " ";
  __clearfcn = "";
  for __i = 1:numel (__blockidx)-1

    ## Extract the block.
    __block = __body(__blockidx(__i):__blockidx(__i+1)-2);

    ## Print the code block before execution if in verbose mode.
    if (__verbose > 0)
      fprintf (__fid, "%s%s\n", __signal_block, __block);
      fflush (__fid);
    endif

    ## Split __block into __type and __code.
    __idx = find (! isletter (__block));
    if (isempty (__idx))
      __type = __block;
      __code = "";
    else
      __type = __block(1:__idx(1)-1);
      __code = __block(__idx(1):length (__block));
    endif

    ## Assume the block will succeed.
    __success = true;
    __msg = [];
    __isxtest = false;

    ### DEMO

    ## If in __grabdemo mode, then don't process any other block type.
    ## So that the other block types don't have to worry about
    ## this __grabdemo mode, the demo block processor grabs all block
    ## types and skips those which aren't demo blocks.

    __isdemo = strcmp (__type, "demo");
    if (__grabdemo || __isdemo)
      __istest = false;

      if (__grabdemo && __isdemo)
        if (isempty (__demo_code))
          __demo_code = __code;
          __demo_idx = [1, length(__demo_code)+1];
        else
          __demo_code = [__demo_code, __code];
          __demo_idx = [__demo_idx, length(__demo_code)+1];
        endif

      elseif (__rundemo && __isdemo)
        try
          ## process the code in an environment without variables
          eval (sprintf ("function __test__ ()\n%s\nendfunction", __code));
          __test__;
          input ("Press <enter> to continue: ", "s");
        catch
          __success = false;
          __msg = [__signal_fail "demo failed\n" lasterr()];
        end_try_catch
        clear __test__;

      endif
      ## Code already processed.
      __code = "";

    ### SHARED

    elseif (strcmp (__type, "shared"))
      __istest = false;

      ## Separate initialization code from variables.
      __idx = find (__code == "\n");
      if (isempty (__idx))
        __vars = __code;
        __code = "";
      else
        __vars = __code (1:__idx(1)-1);
        __code = __code (__idx(1):length (__code));
      endif

      ## Strip comments off the variables.
      __idx = find (__vars == "%" | __vars == "#");
      if (! isempty (__idx))
        __vars = __vars(1:__idx(1)-1);
      endif

      ## Assign default values to variables.
      try
        __vars = deblank (__vars);
        if (! isempty (__vars))
          eval ([strrep(__vars, ",", "=[];"), "=[];"]);
          __shared = __vars;
          __shared_r = ["[ " __vars "] = "];
        else
          __shared = " ";
          __shared_r = " ";
        endif
      catch
        ## Couldn't declare, so don't initialize.
        __code = "";
        __success = false;
        __msg = [__signal_fail "shared variable initialization failed\n"];
      end_try_catch

      ## Initialization code will be evaluated below.

    ### FUNCTION

    elseif (strcmp (__type, "function"))
      __istest = false;
      persistent __fn = 0;
      __name_position = function_name (__block);
      if (isempty (__name_position))
        __success = false;
        __msg = [__signal_fail "test failed: missing function name\n"];
      else
        __name = __block(__name_position(1):__name_position(2));
        __code = __block;
        try
          eval (__code);  # Define the function
          __clearfcn = sprintf ("%sclear %s;\n", __clearfcn, __name);
        catch
          __success = false;
          __msg = [__signal_fail "test failed: syntax error\n" lasterr()];
        end_try_catch
      endif
      __code = "";

    ### ENDFUNCTION

    elseif (strcmp (__type, "endfunction"))
      ## endfunction simply declares the end of a previous function block.
      ## There is no processing to be done here, just skip to next block.
      __istest = false;
      __code = "";

    ### ASSERT/FAIL

    elseif (strcmp (__type, "assert") || strcmp (__type, "fail"))
      __istest = true;
      ## Put the keyword back on the code.
      __code = __block;
      ## The code will be evaluated below as a test block.

    ### ERROR/WARNING

    elseif (strcmp (__type, "error") || strcmp (__type, "warning"))
      __istest = true;
      __iswarning = strcmp (__type, "warning");
      [__pattern, __id, __code] = getpattern (__code);
      if (__id)
        __patstr = ["id=" __id];
      else
        if (! strcmp (__pattern, '.'))
          __patstr = ["<" __pattern ">"];
        else
          __patstr = ifelse (__iswarning, "a warning", "an error");
        endif
      endif
      try
        eval (sprintf ("function __test__(%s)\n%s\nendfunction",
                       __shared, __code));
      catch
        __success = false;
        __msg = [__signal_fails "test failed: syntax error\n" lasterr()];
      end_try_catch

      if (__success)
        __success = false;
        __warnstate = warning ("query", "quiet");
        warning ("on", "quiet");
        ## Clear error and warning strings before starting
        lasterr ("");
        lastwarn ("");
        try
          ## FIXME: lastwarn () must be called once from *WITHIN* the try block
          ##        or subsequent warning/lastwarn statements may fail.
          ##        Likely this is something to do with the specialness of
          ##        the try block which is disabling normal errors.
          lastwarn ();
          eval (sprintf ("__test__(%s);", __shared));
          if (! __iswarning)
            __msg = [__signal_fail "error failed.\n" ...
                     "Expected " __patstr "but got no error\n"];
          else
            if (! isempty (__id))
              [~, __err] = lastwarn ();
              __mismatch = ! strcmp (__err, __id);
            else
              __err = trimerr (lastwarn (), "warning");
              __mismatch = isempty (regexp (__err, __pattern, "once"));
            endif
            warning (__warnstate.state, "quiet");
            if (isempty (__err))
              __msg = [__signal_fail "warning failed.\n" ...
                       "Expected " __patstr " but got no warning\n"];
            elseif (__mismatch)
              __msg = [__signal_fail "warning failed.\n" ...
                       "Expected " __patstr " but got <" __err ">\n"];
            else
              __success = true;
            endif
          endif

        catch
          if (! isempty (__id))
            [~, __err] = lasterr ();
            __mismatch = ! strcmp (__err, __id);
          else
            __err = trimerr (lasterr (), "error");
            __mismatch = isempty (regexp (__err, __pattern, "once"));
          endif
          warning (__warnstate.state, "quiet");
          if (__iswarning)
            __msg = [__signal_fail "warning failed.\n" ...
                     "Expected warning " __patstr ...
                     " but got error <" __err ">\n"];
          elseif (__mismatch)
            __msg = [__signal_fail "error failed.\n" ...
                     "Expected " __patstr " but got <" __err ">\n"];
          else
            __success = true;
          endif
        end_try_catch
        clear __test__;
      endif
      ## Code already processed.
      __code = "";

    ### TESTIF

    elseif (strcmp (__type, "testif"))
      __e = regexp (__code, '.$', 'lineanchors', 'once');
      ## Strip any comment from testif line before looking for features
      __feat_line = strtok (__code(1:__e), '#%'); 
      __feat = regexp (__feat_line, '\w+', 'match');
      __feat = strrep (__feat, "HAVE_", "");
      __have_feat = __have_feature__ (__feat);
      if (__have_feat)
        __istest = true;
        __code = __code(__e + 1 : end);
      else
        __xskip++;
        __istest = false;
        __code = ""; # Skip the code.
        __msg = [__signal_skip "skipped test\n"];
      endif

    ### TEST

    elseif (strcmp (__type, "test"))
      __istest = true;
      ## Code will be evaluated below.

    ### XTEST

    elseif (strcmp (__type, "xtest"))
      __istest = false;
      __isxtest = true;
      ## Code will be evaluated below.

    ### Comment block.

    elseif (strcmp (__block(1:1), "#"))
      __istest = false;
      __code = ""; # skip the code

    ### Unknown block.

    else
      __istest = true;
      __success = false;
      __msg = [__signal_fail "unknown test type!\n"];
      __code = ""; # skip the code
    endif

    ## evaluate code for test, shared, and assert.
    if (! isempty(__code))
      try
        ## FIXME: Must check for embedded test functions, which cause
        ## segfaults, until issues with subfunctions in functions are resolved.
        embed_func = regexp (__code, '^\s*function ', 'once', 'lineanchors');
        if (isempty (embed_func))
          eval (sprintf ("function %s__test__(%s)\n%s\nendfunction",
                         __shared_r, __shared, __code));
          eval (sprintf ("%s__test__(%s);", __shared_r, __shared));
        else
          error (["Functions embedded in %!test blocks are not allowed.\n", ...
                  "Use the %!function/%!endfunction syntax instead to define shared functions for testing.\n"]);
        endif
      catch
        if (strcmp (__type, "xtest"))
           __msg = [__signal_fail "known failure\n" lasterr()];
           __xfail++;
           __success = false;
        else
           __msg = [__signal_fail "test failed\n" lasterr()];
           __success = false;
        endif
        if (isempty (lasterr ()))
          error ("empty error text, probably Ctrl-C --- aborting");
        endif
      end_try_catch
      clear __test__;
    endif

    ## All done.  Remember if we were successful and print any messages.
    if (! isempty (__msg) && (__verbose >= 0 || __logfile))
      ## Make sure the user knows what caused the error.
      if (__verbose < 1)
        fprintf (__fid, "%s%s\n", __signal_block, __block);
        fflush (__fid);
      endif
      fprintf (__fid, "%s\n", __msg);
      fflush (__fid);
      ## Show the variable context.
      if (! strcmp (__type, "error") && ! strcmp (__type, "testif")
          && ! all (__shared == " "))
        fputs (__fid, "shared variables ");
        eval (sprintf ("fdisp(__fid,var2struct(%s));", __shared));
        fflush (__fid);
      endif
    endif
    if (! __success && ! __isxtest)
      __all_success = false;
      ## Stop after 1 error if not in batch mode or only pass/fail requested.
      if (! __batch || nargout == 1)
        if (nargout > 0)
          if (nargout == 1)
            __n = false;
          else
            __n = __nmax = 0;
          endif
        endif
        if (__close_fid)
          fclose (__fid);
        endif
        return;
      endif
    endif
    __tests += (__istest || __isxtest);
    __successes += __success && (__istest || __isxtest);
  endfor

  ## Clear any functions created during test run 
  eval (__clearfcn, "");

  if (nargout == 0)
    if (__tests || __xfail || __xskip)
      if (__xfail)
        printf ("PASSES %d out of %d test%s (%d expected failure%s)\n",
                __successes, __tests, ifelse (__tests > 1, "s", ""),
                __xfail, ifelse (__xfail > 1, "s", ""));
      else
        printf ("PASSES %d out of %d test%s\n", __successes, __tests,
               ifelse (__tests > 1, "s", ""));
      endif
      if (__xskip)
        printf ("Skipped %d test%s due to missing features\n", __xskip,
                ifelse (__xskip > 1, "s", ""));
      endif
    else
      printf ("%s%s has no tests available\n", __signal_empty, __file);
    endif
  elseif (__grabdemo)
    __n    = __demo_code;
    __nmax = __demo_idx;
  elseif (nargout == 1)
    __n = __all_success;
  else
    __n      = __successes;
    __nmax   = __tests;
    __nxfail = __xfail;
    __nskip  = __xskip;
  endif

endfunction


## Create structure with fieldnames the name of the input variables.
function s = var2struct (varargin)
  for i = 1:nargin
    s.(deblank (argn(i,:))) = varargin{i};
  endfor
endfunction

## Find [start,end] of fn in 'function [a,b] = fn'.
function pos = function_name (def)
  pos = [];

  ## Find the end of the name.
  right = find (def == "(", 1);
  if (isempty (right))
    return;
  endif
  right = find (def(1:right-1) != " ", 1, "last");

  ## Find the beginning of the name.
  left = max ([find(def(1:right)==" ", 1, "last"), ...
               find(def(1:right)=="=", 1, "last")]);
  if (isempty (left))
    return;
  endif
  left++;

  ## Return the end points of the name.
  pos = [left, right];
endfunction

## Strip <pattern> from '<pattern> code'.
## Also handles 'id=ID code'
function [pattern, id, rest] = getpattern (str)
  pattern = ".";
  id = [];
  rest = str;
  str = trimleft (str);
  if (! isempty (str) && str(1) == "<")
    close = index (str, ">");
    if (close)
      pattern = str(2:close-1);
      rest = str(close+1:end);
    endif
  elseif (strncmp (str, "id=", 3))
    [id, rest] = strtok (str(4:end));
  endif
endfunction

## Strip '.*prefix:' from '.*prefix: msg\n' and strip trailing blanks.
function msg = trimerr (msg, prefix)
  idx = index (msg, [prefix ":"]);
  if (idx > 0)
    msg(1:idx+length(prefix)) = [];
  endif
  msg = strtrim (msg);
endfunction

## Strip leading blanks from string.
function str = trimleft (str)
  idx = find (! isspace (str), 1);
  str = str(idx:end);
endfunction

function body = __extract_test_code (nm)
  fid = fopen (nm, "rt");
  body = [];
  if (fid >= 0)
    while (! feof (fid))
      ln = fgetl (fid);
      if (length (ln) >= 2 && strcmp (ln(1:2), "%!"))
        body = [body, "\n"];
        if (length (ln) > 2)
          body = [body, ln(3:end)];
        endif
      endif
    endwhile
    fclose (fid);
  endif
endfunction


## example from toeplitz
%!shared msg1,msg2
%! msg1 = "C must be a vector";
%! msg2 = "C and R must be vectors";
%!fail ("toeplitz ([])", msg1)
%!fail ("toeplitz ([1,2;3,4])", msg1)
%!fail ("toeplitz ([1,2],[])", msg2)
%!fail ("toeplitz ([1,2],[1,2;3,4])", msg2)
%!fail ("toeplitz ([1,2;3,4],[1,2])", msg2)
%!test fail ("toeplitz", "Invalid call to toeplitz")
%!fail ("toeplitz (1, 2, 3)", "Invalid call to toeplitz")
%!test assert (toeplitz ([1,2,3], [1,4]), [1,4; 2,1; 3,2])
%!assert (toeplitz ([1,2,3], [1,4]), [1,4; 2,1; 3,2])
%!demo toeplitz ([1,2,3,4],[1,5,6])

## example from kron
%!error <Invalid call to kron> kron ()
%!error <Invalid call to kron> kron (1)
%!test assert (isempty (kron ([], rand (3, 4))))
%!test assert (isempty (kron (rand (3, 4), [])))
%!test assert (isempty (kron ([], [])))
%!shared A, B
%!test
%! A = [1, 2, 3; 4, 5, 6];
%! B = [1, -1; 2, -2];
%!assert (size (kron (zeros (3, 0), A)), [ 3*rows(A), 0 ])
%!assert (size (kron (zeros (0, 3), A)), [ 0, 3*columns(A) ])
%!assert (size (kron (A, zeros (3, 0))), [ 3*rows(A), 0 ])
%!assert (size (kron (A, zeros (0, 3))), [ 0, 3*columns(A) ])
%!assert (kron (pi, e), pi*e)
%!assert (kron (pi, A), pi*A)
%!assert (kron (A, e), e*A)
%!assert (kron ([1, 2, 3], A), [ A, 2*A, 3*A ])
%!assert (kron ([1; 2; 3], A), [ A; 2*A; 3*A ])
%!assert (kron ([1, 2; 3, 4], A), [ A, 2*A; 3*A, 4*A ])
%!test
%! res = [1,-1,2,-2,3,-3; 2,-2,4,-4,6,-6; 4,-4,5,-5,6,-6; 8,-8,10,-10,12,-12];
%! assert (kron (A, B), res);
%!shared  # clear out shared variables

## Now verify test() itself

## Test 'fail' keyword
%!fail ("test", "Invalid call to test")  # no args, generates usage()
%!fail ("test (1,2,3,4)", "usage.*test") # too many args, generates usage()
%!fail ('test ("test", "bogus")', "unknown flag")  # incorrect args
%!fail ('garbage','garbage.*undefined')  # usage on nonexistent function should be

## Test 'error' keyword 
%!error test              # no args, generates usage()
%!error test (1,2,3,4)    # too many args, generates usage()
%!error <unknown flag> test ("test", "bogus"); # incorrect args
%!error test ("test", "bogus");  # test without pattern
%!error <'garbage' undefined> garbage; # usage on nonexistent function is error

## Test 'warning' keyword 
%!warning warning ("warning message");   # no pattern
%!warning <warning message> warning ("warning message");   # with pattern

## Test 'shared' keyword
%!shared a                # create a shared variable
%!test a = 3;             # assign to a shared variable
%!test assert (a, 3)      # variable should equal 3
%!shared b,c              # replace shared variables
%!test assert (!exist ("a", "var"));  # a no longer exists
%!test assert (isempty (b));   # variables start off empty
%!shared a,b,c            # recreate a shared variable
%!test assert (isempty (a));   # value is empty even if it had a previous value
%!test a=1; b=2; c=3;   # give values to all variables
%!test assert ([a,b,c], [1,2,3]); # test all of them together
%!test c=6;               # update a value
%!test assert ([a,b,c], [1,2,6]); # show that the update sticks
%!shared                  # clear all shared variables
%!test assert (!exist ("a", "var")) # show that they are cleared
%!shared a,b,c            # support for initializer shorthand
%! a=1; b=2; c=4;
%!shared                  # clear all shared variables for remainder of tests

## Test 'function' keyword 
%!function x = __test_a (y)
%! x = 2*y;
%!endfunction
%!assert (__test_a (2), 4)  # Test a test function

%!function __test_a (y)
%! x = 2*y;
%!endfunction
%!test
%! __test_a (2);            # Test a test function with no return value

%!function [x,z] = __test_a (y)
%! x = 2*y;
%! z = 3*y;
%!endfunction
%!test                      
%! [x,z] = __test_a (3);    # Test a test function with multiple returns
%! assert (x,6);
%! assert (z,9);

## Test 'assert' keyword 
%!assert (isempty ([]))     # support for test assert shorthand
%!assert (size (ones (1,2,3)), [1 2 3])

## Test 'demo' keyword 
%!demo                      # multiline demo block
%! t = [0:0.01:2*pi]; x = sin (t);
%! plot (t,x);
%! % you should now see a sine wave in your figure window

%!demo a=3                  # single line demo blocks work too

%!test
%! [code, idx] = test ("test", "grabdemo");
%! assert (numel (idx), 4);
%! assert (code(idx(3):end),
%!         " a=3                  # single line demo blocks work too");

## Test 'testif' keyword 
%!testif HAVE_BOGUS_FEATURE
%! error ("testif executed code despite not having feature");

## Test 'xtest' keyword 
%!xtest
%! assert (1, 1);      # Test passes
%!xtest
%! assert (0, 1);      # Test fails

## Test comment block. it can contain anything.
%!##
%! it is the "#" as the block type that makes it a comment
%! and it stays as a comment even through continuation lines
%! which means that it works well with commenting out whole tests

%% Test test() input validation
%!error <NAME must be a string> test (1)
%!error <second argument must be a string> test ("ls", 1)
%!error test ([], "normal")

## All of the following tests should fail.  These tests should
## be disabled unless you are developing test() since users don't
## like to be presented with expected failures.  I use '% !' to disable.
% !test   error("---------Failure tests.  Use test('test','verbose',1)");
% !test   assert([a,b,c],[1,3,6]);   # variables have wrong values
% !bogus                     # unknown block type
% !error  toeplitz([1,2,3]); # correct usage
% !test   syntax errors)     # syntax errors fail properly
% !shared garbage in         # variables must be comma separated
% !error  syntax++error      # error test fails on syntax errors
% !error  "succeeds.";       # error test fails if code succeeds
% !error <wrong pattern> error("message")  # error pattern must match
% !demo   with syntax error  # syntax errors in demo fail properly
% !shared a,b,c
% !demo                      # shared variables not available in demo
% ! assert (exist ("a", "var"))
% !error
% ! test ('/etc/passwd');
% ! test ("nonexistent file");
% ! ## These don't signal an error, so the test for an error fails. Note
% ! ## that the call doesn't reference the current fid (it is unavailable),
% ! ## so of course the informational message is not printed in the log.