Initial support for ad hoc recipes (still work in progress)

1 files changed, 53 insertions, 1973 deletions

diff --git a/libbuild2/test/script/runner.cxx b/libbuild2/test/script/runner.cxx
index b40dea8..03a1f0e 100644
--- a/libbuild2/test/script/runner.cxx
+++ b/libbuild2/test/script/runner.cxx
@@ -3,696 +3,17 @@
 
 #include <libbuild2/test/script/runner.hxx>
 
-#include <ios> // streamsize
-
-#include <libbutl/regex.mxx>
-#include <libbutl/builtin.mxx>
-#include <libbutl/fdstream.mxx>     // fdopen_mode, fddup()
-#include <libbutl/filesystem.mxx>   // path_search()
-#include <libbutl/path-pattern.mxx>
-
-#include <libbuild2/variable.hxx>
-#include <libbuild2/filesystem.hxx>
-#include <libbuild2/diagnostics.hxx>
+#include <libbuild2/script/run.hxx>
 
 #include <libbuild2/test/common.hxx>
 
-#include <libbuild2/test/script/regex.hxx>
-#include <libbuild2/test/script/parser.hxx>
-#include <libbuild2/test/script/builtin-options.hxx>
-
-using namespace std;
-using namespace butl;
-
 namespace build2
 {
   namespace test
   {
     namespace script
     {
-      // Normalize a path. Also make the relative path absolute using the
-      // scope's working directory unless it is already absolute.
-      //
-      static path
-      normalize (path p, const scope& sp, const location& l)
-      {
-        path r (p.absolute () ? move (p) : sp.wd_path / move (p));
-
-        try
-        {
-          r.normalize ();
-        }
-        catch (const invalid_path& e)
-        {
-          fail (l) << "invalid file path " << e.path;
-        }
-
-        return r;
-      }
-
-      // Check if a path is not empty, the referenced file exists and is not
-      // empty.
-      //
-      static bool
-      non_empty (const path& p, const location& ll)
-      {
-        if (p.empty () || !exists (p))
-          return false;
-
-        try
-        {
-          ifdstream is (p);
-          return is.peek () != ifdstream::traits_type::eof ();
-        }
-        catch (const io_error& e)
-        {
-          // While there can be no fault of the test command being currently
-          // executed let's add the location anyway to ease the
-          // troubleshooting. And let's stick to that principle down the road.
-          //
-          fail (ll) << "unable to read " << p << ": " << e << endf;
-        }
-      }
-
-      // If the file exists, not empty and not larger than 4KB print it to the
-      // diag record. The file content goes from the new line and is not
-      // indented.
-      //
-      static void
-      print_file (diag_record& d, const path& p, const location& ll)
-      {
-        if (exists (p))
-        {
-          try
-          {
-            ifdstream is (p, ifdstream::badbit);
-
-            if (is.peek () != ifdstream::traits_type::eof ())
-            {
-              char buf[4096 + 1]; // Extra byte is for terminating '\0'.
-
-              // Note that the string is always '\0'-terminated with a maximum
-              // sizeof (buf) - 1 bytes read.
-              //
-              is.getline (buf, sizeof (buf), '\0');
-
-              // Print if the file fits 4KB-size buffer. Note that if it
-              // doesn't the failbit is set.
-              //
-              if (is.eof ())
-              {
-                // Suppress the trailing newline character as the diag record
-                // adds it's own one when flush.
-                //
-                streamsize n (is.gcount ());
-                assert (n > 0);
-
-                // Note that if the file contains '\0' it will also be counted
-                // by gcount(). But even in the worst case we will stay in the
-                // buffer boundaries (and so not crash).
-                //
-                if (buf[n - 1] == '\n')
-                  buf[n - 1] = '\0';
-
-                d << '\n' << buf;
-              }
-            }
-          }
-          catch (const io_error& e)
-          {
-            fail (ll) << "unable to read " << p << ": " << e;
-          }
-        }
-      }
-
-      // Print first 10 directory sub-entries to the diag record. The directory
-      // must exist.
-      //
-      static void
-      print_dir (diag_record& d, const dir_path& p, const location& ll)
-      {
-        try
-        {
-          size_t n (0);
-          for (const dir_entry& de: dir_iterator (p,
-                                                  false /* ignore_dangling */))
-          {
-            if (n++ < 10)
-              d << '\n' << (de.ltype () == entry_type::directory
-                            ? path_cast<dir_path> (de.path ())
-                            : de.path ());
-          }
-
-          if (n > 10)
-            d << "\nand " << n - 10 << " more file(s)";
-        }
-        catch (const system_error& e)
-        {
-          fail (ll) << "unable to iterate over " << p << ": " << e;
-        }
-      }
-
-      // Save a string to the file. Fail if exception is thrown by underlying
-      // operations.
-      //
-      static void
-      save (const path& p, const string& s, const location& ll)
-      {
-        try
-        {
-          ofdstream os (p);
-          os << s;
-          os.close ();
-        }
-        catch (const io_error& e)
-        {
-          fail (ll) << "unable to write to " << p << ": " << e;
-        }
-      }
-
-      // Return the value of the test.target variable.
-      //
-      static inline const target_triplet&
-      test_target (const script& s)
-      {
-        // @@ Would be nice to use cached value from test::common_data.
-        //
-        if (auto r = cast_null<target_triplet> (s.test_target["test.target"]))
-          return *r;
-
-        // We set it to default value in init() so it can only be NULL if the
-        // user resets it.
-        //
-        fail << "invalid test.target value" << endf;
-      }
-
-      // Transform string according to here-* redirect modifiers from the {/}
-      // set.
-      //
-      static string
-      transform (const string& s,
-                 bool regex,
-                 const string& modifiers,
-                 const script& scr)
-      {
-        if (modifiers.find ('/') == string::npos)
-          return s;
-
-        // For targets other than Windows leave the string intact.
-        //
-        if (test_target (scr).class_ != "windows")
-          return s;
-
-        // Convert forward slashes to Windows path separators (escape for
-        // regex).
-        //
-        string r;
-        for (size_t p (0);;)
-        {
-          size_t sp (s.find ('/', p));
-
-          if (sp != string::npos)
-          {
-            r.append (s, p, sp - p);
-            r.append (regex ? "\\\\" : "\\");
-            p = sp + 1;
-          }
-          else
-          {
-            r.append (s, p, sp);
-            break;
-          }
-        }
-
-        return r;
-      }
-
-      // Check if the test command output matches the expected result (redirect
-      // value). Noop for redirect types other than none, here_*.
-      //
-      static bool
-      check_output (const path& pr,
-                    const path& op,
-                    const path& ip,
-                    const redirect& rd,
-                    const location& ll,
-                    scope& sp,
-                    bool diag,
-                    const char* what)
-      {
-        auto input_info = [&ip, &ll] (diag_record& d)
-        {
-          if (non_empty (ip, ll))
-            d << info << "stdin: " << ip;
-        };
-
-        auto output_info = [&what, &ll] (diag_record& d,
-                                         const path& p,
-                                         const char* prefix = "",
-                                         const char* suffix = "")
-        {
-          if (non_empty (p, ll))
-            d << info << prefix << what << suffix << ": " << p;
-          else
-            d << info << prefix << what << suffix << " is empty";
-        };
-
-        if (rd.type == redirect_type::none)
-        {
-          // Check that there is no output produced.
-          //
-          assert (!op.empty ());
-
-          if (!non_empty (op, ll))
-            return true;
-
-          if (diag)
-          {
-            diag_record d (error (ll));
-            d << pr << " unexpectedly writes to " << what <<
-              info << what << ": " << op;
-
-            input_info (d);
-
-            // Print cached output.
-            //
-            print_file (d, op, ll);
-          }
-
-          // Fall through (to return false).
-          //
-        }
-        else if (rd.type == redirect_type::here_str_literal ||
-                 rd.type == redirect_type::here_doc_literal ||
-                 (rd.type == redirect_type::file &&
-                  rd.file.mode == redirect_fmode::compare))
-        {
-          // The expected output is provided as a file or as a string. Save the
-          // string to a file in the later case.
-          //
-          assert (!op.empty ());
-
-          path eop;
-
-          if (rd.type == redirect_type::file)
-            eop = normalize (rd.file.path, sp, ll);
-          else
-          {
-            eop = path (op + ".orig");
-            save (eop, transform (rd.str, false, rd.modifiers, sp.root), ll);
-            sp.clean_special (eop);
-          }
-
-          // Use the diff utility for comparison.
-          //
-          path dp ("diff");
-          process_path pp (run_search (dp, true));
-
-          cstrings args {pp.recall_string (), "-u"};
-
-          // Ignore Windows newline fluff if that's what we are running on.
-          //
-          if (test_target (sp.root).class_ == "windows")
-            args.push_back ("--strip-trailing-cr");
-
-          args.push_back (eop.string ().c_str ());
-          args.push_back (op.string ().c_str ());
-          args.push_back (nullptr);
-
-          if (verb >= 2)
-            print_process (args);
-
-          try
-          {
-            // Save diff's stdout to a file for troubleshooting and for the
-            // optional (if not too large) printing (at the end of
-            // diagnostics).
-            //
-            path ep (op + ".diff");
-            auto_fd efd;
-
-            try
-            {
-              efd = fdopen (ep, fdopen_mode::out | fdopen_mode::create);
-              sp.clean_special (ep);
-            }
-            catch (const io_error& e)
-            {
-              fail (ll) << "unable to write to " << ep << ": " << e;
-            }
-
-            // Diff utility prints the differences to stdout. But for the
-            // user it is a part of the test failure diagnostics so let's
-            // redirect stdout to stderr.
-            //
-            process p (pp, args.data (), 0, 2, efd.get ());
-            efd.reset ();
-
-            if (p.wait ())
-              return true;
-
-            assert (p.exit);
-            const process_exit& pe (*p.exit);
-
-            // Note that both POSIX and GNU diff report error by exiting with
-            // the code > 1.
-            //
-            if (!pe.normal () || pe.code () > 1)
-            {
-              diag_record d (fail (ll));
-              print_process (d, args);
-              d << " " << pe;
-            }
-
-            // Output doesn't match the expected result.
-            //
-            if (diag)
-            {
-              diag_record d (error (ll));
-              d << pr << " " << what << " doesn't match expected";
-
-              output_info (d, op);
-              output_info (d, eop, "expected ");
-              output_info (d, ep, "", " diff");
-              input_info  (d);
-
-              print_file (d, ep, ll);
-            }
-
-            // Fall through (to return false).
-            //
-          }
-          catch (const process_error& e)
-          {
-            error (ll) << "unable to execute " << pp << ": " << e;
-
-            if (e.child)
-              exit (1);
-
-            throw failed ();
-          }
-        }
-        else if (rd.type == redirect_type::here_str_regex ||
-                 rd.type == redirect_type::here_doc_regex)
-        {
-          // The overall plan is:
-          //
-          // 1. Create regex line string. While creating it's line characters
-          //    transform regex lines according to the redirect modifiers.
-          //
-          // 2. Create line regex using the line string. If creation fails
-          //    then save the (transformed) regex redirect to a file for
-          //    troubleshooting.
-          //
-          // 3. Parse the output into the literal line string.
-          //
-          // 4. Match the output line string with the line regex.
-          //
-          // 5. If match fails save the (transformed) regex redirect to a file
-          //    for troubleshooting.
-          //
-          using namespace regex;
-
-          assert (!op.empty ());
-
-          // Create regex line string.
-          //
-          line_pool pool;
-          line_string rls;
-          const regex_lines rl (rd.regex);
-
-          // Parse regex flags.
-          //
-          // When add support for new flags don't forget to update
-          // parse_regex().
-          //
-          auto parse_flags = [] (const string& f) -> char_flags
-          {
-            char_flags r (char_flags::none);
-
-            for (char c: f)
-            {
-              switch (c)
-              {
-              case 'd': r |= char_flags::idot;  break;
-              case 'i': r |= char_flags::icase; break;
-              default: assert (false); // Error so should have been checked.
-              }
-            }
-
-            return r;
-          };
-
-          // Return original regex line with the transformation applied.
-          //
-          auto line = [&rl, &rd, &sp] (const regex_line& l) -> string
-          {
-            string r;
-            if (l.regex)                  // Regex (possibly empty),
-            {
-              r += rl.intro;
-              r += transform (l.value, true, rd.modifiers, sp.root);
-              r += rl.intro;
-              r += l.flags;
-            }
-            else if (!l.special.empty ()) // Special literal.
-              r += rl.intro;
-            else                          // Textual literal.
-              r += transform (l.value, false, rd.modifiers, sp.root);
-
-            r += l.special;
-            return r;
-          };
-
-          // Return regex line location.
-          //
-          // Note that we rely on the fact that the command and regex lines
-          // are always belong to the same testscript file.
-          //
-          auto loc = [&ll] (uint64_t line, uint64_t column) -> location
-          {
-            location r (ll);
-            r.line = line;
-            r.column = column;
-            return r;
-          };
-
-          // Save the regex to file for troubleshooting, return the file path
-          // it have been saved to.
-          //
-          // Note that we save the regex on line regex creation failure or if
-          // the program output doesn't match.
-          //
-          auto save_regex = [&op, &rl, &rd, &ll, &line] () -> path
-          {
-            path rp (op + ".regex");
-
-            // Encode here-document regex global flags if present as a file
-            // name suffix. For example if icase and idot flags are specified
-            // the name will look like:
-            //
-            // test/1/stdout.regex-di
-            //
-            if (rd.type == redirect_type::here_doc_regex && !rl.flags.empty ())
-              rp += '-' + rl.flags;
-
-            // Note that if would be more efficient to directly write chunks
-            // to file rather than to compose a string first. Hower we don't
-            // bother (about performance) for the sake of the code as we
-            // already failed.
-            //
-            string s;
-            for (auto b (rl.lines.cbegin ()), i (b), e (rl.lines.cend ());
-                 i != e; ++i)
-            {
-              if (i != b) s += '\n';
-              s += line (*i);
-            }
-
-            save (rp, s, ll);
-            return rp;
-          };
-
-          // Finally create regex line string.
-          //
-          // Note that diagnostics doesn't refer to the program path as it is
-          // irrelevant to failures at this stage.
-          //
-          char_flags gf (parse_flags (rl.flags)); // Regex global flags.
-
-          for (const auto& l: rl.lines)
-          {
-            if (l.regex) // Regex (with optional special characters).
-            {
-              line_char c;
-
-              // Empty regex is a special case repesenting the blank line.
-              //
-              if (l.value.empty ())
-                c = line_char ("", pool);
-              else
-              {
-                try
-                {
-                  string s (transform (l.value, true, rd.modifiers, sp.root));
-
-                  c = line_char (
-                    char_regex (s, gf | parse_flags (l.flags)), pool);
-                }
-                catch (const regex_error& e)
-                {
-                  // Print regex_error description if meaningful.
-                  //
-                  diag_record d (fail (loc (l.line, l.column)));
-
-                  if (rd.type == redirect_type::here_str_regex)
-                    d << "invalid " << what << " regex redirect" << e <<
-                      info << "regex: '" << line (l) << "'";
-                  else
-                    d << "invalid char-regex in " << what << " regex redirect"
-                      << e <<
-                      info << "regex line: '" << line (l) << "'";
-
-                  d << endf;
-                }
-              }
-
-              rls += c; // Append blank literal or regex line char.
-            }
-            else if (!l.special.empty ()) // Special literal.
-            {
-              // Literal can not be followed by special characters in the same
-              // line.
-              //
-              assert (l.value.empty ());
-            }
-            else // Textual literal.
-            {
-              // Append literal line char.
-              //
-              rls += line_char (
-                transform (l.value, false, rd.modifiers, sp.root), pool);
-            }
-
-            for (char c: l.special)
-            {
-              if (line_char::syntax (c))
-                rls += line_char (c); // Append special line char.
-              else
-                fail (loc (l.line, l.column))
-                  << "invalid syntax character '" << c << "' in " << what
-                  << " regex redirect" <<
-                  info << "regex line: '" << line (l) << "'";
-            }
-          }
-
-          // Create line regex.
-          //
-          line_regex regex;
-
-          try
-          {
-            regex = line_regex (move (rls), move (pool));
-          }
-          catch (const regex_error& e)
-          {
-            // Note that line regex creation can not fail for here-string
-            // redirect as it doesn't have syntax line chars. That in
-            // particular means that end_line and end_column are meaningful.
-            //
-            assert (rd.type == redirect_type::here_doc_regex);
-
-            diag_record d (fail (loc (rd.end_line, rd.end_column)));
-
-            // Print regex_error description if meaningful.
-            //
-            d << "invalid " << what << " regex redirect" << e;
-
-            output_info (d, save_regex (), "", " regex");
-          }
-
-          // Parse the output into the literal line string.
-          //
-          line_string ls;
-
-          try
-          {
-            // Do not throw when eofbit is set (end of stream reached), and
-            // when failbit is set (getline() failed to extract any character).
-            //
-            // Note that newlines are treated as line-chars separators. That
-            // in particular means that the trailing newline produces a blank
-            // line-char (empty literal). Empty output produces the zero-length
-            // line-string.
-            //
-            // Also note that we strip the trailing CR characters (otherwise
-            // can mismatch when cross-test).
-            //
-            ifdstream is (op, ifdstream::badbit);
-            is.peek (); // Sets eofbit for an empty stream.
-
-            while (!is.eof ())
-            {
-              string s;
-              getline (is, s);
-
-              // It is safer to strip CRs in cycle, as msvcrt unexplainably
-              // adds too much trailing junk to the system_error descriptions,
-              // and so it can appear in programs output. For example:
-              //
-              // ...: Invalid data.\r\r\n
-              //
-              // Note that our custom operator<<(ostream&, const exception&)
-              // removes this junk.
-              //
-              while (!s.empty () && s.back () == '\r')
-                s.pop_back ();
-
-              ls += line_char (move (s), regex.pool);
-            }
-          }
-          catch (const io_error& e)
-          {
-            fail (ll) << "unable to read " << op << ": " << e;
-          }
-
-          // Match the output with the regex.
-          //
-          if (regex_match (ls, regex)) // Doesn't throw.
-            return true;
-
-          // Output doesn't match the regex. We save the regex to file for
-          // troubleshooting regardless of whether we print the diagnostics or
-          // not. We, however, register it for cleanup in the later case (the
-          // expression may still succeed, we can be evaluating the if
-          // condition, etc).
-          //
-          path rp (save_regex ());
-
-          if (diag)
-          {
-            diag_record d (error (ll));
-            d << pr << " " << what << " doesn't match regex";
-
-            output_info (d, op);
-            output_info (d, rp, "", " regex");
-            input_info  (d);
-
-            // Print cached output.
-            //
-            print_file (d, op, ll);
-          }
-          else
-            sp.clean_special (rp);
-
-          // Fall through (to return false).
-          //
-        }
-        else // Noop.
-          return true;
-
-        return false;
-      }
+      using namespace build2::script;
 
       bool default_runner::
       test (scope& s) const
@@ -703,7 +24,7 @@ namespace build2
       void default_runner::
       enter (scope& sp, const location&)
       {
-        context& ctx (sp.root.target_scope.ctx);
+        context& ctx (sp.context);
 
         auto df = make_diag_frame (
           [&sp](const diag_record& dr)
@@ -730,29 +51,25 @@ namespace build2
           sp.parent == nullptr
           ? mkdir_buildignore (
             ctx,
-            sp.wd_path,
+            *sp.work_dir.path,
             sp.root.target_scope.root_scope ()->root_extra->buildignore_file,
             2)
-          : mkdir (sp.wd_path, 2));
+          : mkdir (*sp.work_dir.path, 2));
 
         if (r == mkdir_status::already_exists)
-          fail << "working directory " << sp.wd_path << " already exists" <<
+          fail << diag_path (sp.work_dir) << " already exists" <<
             info << "are tests stomping on each other's feet?";
 
         // We don't change the current directory here but indicate that the
         // scope test commands will be executed in that directory.
         //
         if (verb >= 2)
-          text << "cd " << sp.wd_path;
-
-        sp.clean ({cleanup_type::always, sp.wd_path}, true);
+          text << "cd " << *sp.work_dir.path;
       }
 
       void default_runner::
       leave (scope& sp, const location& ll)
       {
-        context& ctx (sp.root.target_scope.ctx);
-
         auto df = make_diag_frame (
           [&sp](const diag_record& dr)
           {
@@ -766,200 +83,30 @@ namespace build2
         //
         if (common_.after == output_after::clean)
         {
-          // Note that we operate with normalized paths here.
-          //
-          // Remove special files. The order is not important as we don't
-          // expect directories here.
-          //
-          for (const auto& p: sp.special_cleanups)
-          {
-            // Remove the file if exists. Fail otherwise.
-            //
-            if (rmfile (ctx, p, 3) == rmfile_status::not_exist)
-              fail (ll) << "registered for cleanup special file " << p
-                        << " does not exist";
-          }
-
-          // Remove files and directories in the order opposite to the order of
-          // cleanup registration.
-          //
-          for (const auto& c: reverse_iterate (sp.cleanups))
-          {
-            cleanup_type t (c.type);
-
-            // Skip whenever the path exists or not.
-            //
-            if (t == cleanup_type::never)
-              continue;
-
-            const path& cp (c.path);
+          clean (sp, ll);
 
-            // Wildcard with the last component being '***' (without trailing
-            // separator) matches all files and sub-directories recursively as
-            // well as the start directories itself. So we will recursively
-            // remove the directories that match the parent (for the original
-            // path) directory wildcard.
-            //
-            bool recursive (cp.leaf ().representation () == "***");
-            const path& p (!recursive ? cp : cp.directory ());
+          context& ctx (sp.context);
 
-            // Remove files or directories using wildcard.
-            //
-            if (path_pattern (p))
-            {
-              bool removed (false);
+          rmdir_status r (
+            sp.parent == nullptr
+            ?  rmdir_buildignore (ctx,
+                                  *sp.work_dir.path,
+                                  sp.root.target_scope.root_scope ()->
+                                    root_extra->buildignore_file,
+                                  2)
+            : rmdir (ctx, *sp.work_dir.path, 2));
 
-              auto rm = [&cp, recursive, &removed, &sp, &ll, &ctx]
-                (path&& pe, const string&, bool interm)
-              {
-                if (!interm)
-                {
-                  // While removing the entry we can get not_exist due to
-                  // racing conditions, but that's ok if somebody did our job.
-                  // Note that we still set the removed flag to true in this
-                  // case.
-                  //
-                  removed = true; // Will be meaningless on failure.
-
-                  if (pe.to_directory ())
-                  {
-                    dir_path d (path_cast<dir_path> (pe));
-
-                    if (!recursive)
-                    {
-                      rmdir_status r (rmdir (ctx, d, 3));
-
-                      if (r != rmdir_status::not_empty)
-                        return true;
-
-                      diag_record dr (fail (ll));
-                      dr << "registered for cleanup directory " << d
-                         << " is not empty";
-
-                      print_dir (dr, d, ll);
-                      dr << info << "wildcard: '" << cp << "'";
-                    }
-                    else
-                    {
-                      // Don't remove the working directory (it will be removed
-                      // by the dedicated cleanup).
-                      //
-                      // Cast to uint16_t to avoid ambiguity with
-                      // libbutl::rmdir_r().
-                      //
-                      rmdir_status r (rmdir_r (ctx, d, d != sp.wd_path, 3));
-
-                      if (r != rmdir_status::not_empty)
-                        return true;
-
-                      // The directory is unlikely to be current but let's keep
-                      // for completeness.
-                      //
-                      fail (ll) << "registered for cleanup wildcard " << cp
-                                << " matches the current directory";
-                    }
-                  }
-                  else
-                    rmfile (ctx, pe, 3);
-                }
-
-                return true;
-              };
-
-              // Note that here we rely on the fact that recursive iterating
-              // goes depth-first (which make sense for the cleanup).
-              //
-              try
-              {
-                // Doesn't follow symlinks.
-                //
-                path_search (p,
-                             rm,
-                             dir_path () /* start */,
-                             path_match_flags::none);
-              }
-              catch (const system_error& e)
-              {
-                fail (ll) << "unable to cleanup wildcard " << cp << ": " << e;
-              }
-
-              // Removal of no filesystem entries is not an error for 'maybe'
-              // cleanup type.
-              //
-              if (removed || t == cleanup_type::maybe)
-                continue;
-
-              fail (ll) << "registered for cleanup wildcard " << cp
-                        << " doesn't match any "
-                        << (recursive
-                            ? "path"
-                            : p.to_directory ()
-                              ? "directory"
-                              : "file");
-            }
-
-            // Remove the directory if exists and empty. Fail otherwise.
-            // Removal of non-existing directory is not an error for 'maybe'
-            // cleanup type.
-            //
-            if (p.to_directory ())
-            {
-              dir_path d (path_cast<dir_path> (p));
-              bool wd (d == sp.wd_path);
-
-              // Trace the scope working directory removal with the verbosity
-              // level 2 (that was used for its creation). For other
-              // directories use level 3 (as for other cleanups).
-              //
-              int v (wd ? 2 : 3);
-
-              // Don't remove the working directory for the recursive cleanup
-              // (it will be removed by the dedicated one).
-              //
-              // Note that the root working directory contains the
-              // .buildignore file (see above).
-              //
-              // @@ If 'd' is a file then will fail with a diagnostics having
-              //    no location info. Probably need to add an optional location
-              //    parameter to rmdir() function. The same problem exists for
-              //    a file cleanup when try to rmfile() directory instead of
-              //    file.
-              //
-              rmdir_status r (
-                recursive
-                ? rmdir_r (ctx, d, !wd, static_cast <uint16_t> (v))
-                : (wd && sp.parent == nullptr
-                   ? rmdir_buildignore (
-                       ctx,
-                       d,
-                       sp.root.target_scope.root_scope ()->root_extra->
-                         buildignore_file,
-                       v)
-                   : rmdir (ctx, d, v)));
-
-              if (r == rmdir_status::success ||
-                  (r == rmdir_status::not_exist && t == cleanup_type::maybe))
-                continue;
-
-              diag_record dr (fail (ll));
-              dr << "registered for cleanup directory " << d
-                 << (r == rmdir_status::not_exist
-                     ? " does not exist"
-                     : !recursive
-                       ? " is not empty"
-                       : " is current");
+          if (r != rmdir_status::success)
+          {
+            diag_record dr (fail (ll));
 
-              if (r == rmdir_status::not_empty)
-                print_dir (dr, d, ll);
-            }
+            dr << diag_path (sp.work_dir)
+               << (r == rmdir_status::not_exist
+                   ? " does not exist"
+                   : " is not empty");
 
-            // Remove the file if exists. Fail otherwise. Removal of
-            // non-existing file is not an error for 'maybe' cleanup type.
-            //
-            if (rmfile (ctx, p, 3) == rmfile_status::not_exist &&
-                t == cleanup_type::always)
-              fail (ll) << "registered for cleanup file " << p
-                        << " does not exist";
+            if (r == rmdir_status::not_empty)
+              print_dir (dr, *sp.work_dir.path, ll);
           }
         }
 
@@ -968,1102 +115,14 @@ namespace build2
         //
         if (verb >= 2)
           text << "cd " << (sp.parent != nullptr
-                            ? sp.parent->wd_path
-                            : sp.wd_path.directory ());
-      }
-
-      // The exit pseudo-builtin: exit the current scope successfully, or
-      // print the diagnostics and exit the current scope and all the outer
-      // scopes unsuccessfully. Always throw exit_scope exception.
-      //
-      // exit [<diagnostics>]
-      //
-      [[noreturn]] static void
-      exit_builtin (const strings& args, const location& ll)
-      {
-        auto i (args.begin ());
-        auto e (args.end ());
-
-        // Process arguments.
-        //
-        // If no argument is specified, then exit successfully. Otherwise,
-        // print the diagnostics and exit unsuccessfully.
-        //
-        if (i == e)
-          throw exit_scope (true);
-
-        const string& s (*i++);
-
-        if (i != e)
-          fail (ll) << "unexpected argument '" << *i << "'";
-
-        error (ll) << s;
-        throw exit_scope (false);
-      }
-
-      // The set pseudo-builtin: set variable from the stdin input.
-      //
-      // set [-e|--exact] [(-n|--newline)|(-w|--whitespace)] [<attr>] <var>
-      //
-      static void
-      set_builtin (scope& sp,
-                   const strings& args,
-                   auto_fd in,
-                   const location& ll)
-      {
-        try
-        {
-          // Do not throw when eofbit is set (end of stream reached), and
-          // when failbit is set (read operation failed to extract any
-          // character).
-          //
-          ifdstream cin  (move (in), ifdstream::badbit);
-
-          // Parse arguments.
-          //
-          cli::vector_scanner scan (args);
-          set_options ops (scan);
-
-          if (ops.whitespace () && ops.newline ())
-            fail (ll) << "both -n|--newline and -w|--whitespace specified";
-
-          if (!scan.more ())
-            fail (ll) << "missing variable name";
-
-          string a (scan.next ()); // Either attributes or variable name.
-          const string* ats (!scan.more () ? nullptr : &a);
-          const string& vname (!scan.more () ? a : scan.next ());
-
-          if (scan.more ())
-            fail (ll) << "unexpected argument '" << scan.next () << "'";
-
-          if (ats != nullptr && ats->empty ())
-            fail (ll) << "empty variable attributes";
-
-          if (vname.empty ())
-            fail (ll) << "empty variable name";
-
-          // Read the input.
-          //
-          cin.peek (); // Sets eofbit for an empty stream.
-
-          names ns;
-          while (!cin.eof ())
-          {
-            // Read next element that depends on the whitespace mode being
-            // enabled or not. For the later case it also make sense to strip
-            // the trailing CRs that can appear while cross-testing Windows
-            // target or as a part of msvcrt junk production (see above).
-            //
-            string s;
-            if (ops.whitespace ())
-              cin >> s;
-            else
-            {
-              getline (cin, s);
-
-              while (!s.empty () && s.back () == '\r')
-                s.pop_back ();
-            }
-
-            // If failbit is set then we read nothing into the string as eof is
-            // reached. That in particular means that the stream has trailing
-            // whitespaces (possibly including newlines) if the whitespace mode
-            // is enabled, or the trailing newline otherwise. If so then
-            // we append the "blank" to the variable value in the exact mode
-            // prior to bailing out.
-            //
-            if (cin.fail ())
-            {
-              if (ops.exact ())
-              {
-                if (ops.whitespace () || ops.newline ())
-                  ns.emplace_back (move (s)); // Reuse empty string.
-                else if (ns.empty ())
-                  ns.emplace_back ("\n");
-                else
-                  ns[0].value += '\n';
-              }
-
-              break;
-            }
-
-            if (ops.whitespace () || ops.newline () || ns.empty ())
-              ns.emplace_back (move (s));
-            else
-            {
-              ns[0].value += '\n';
-              ns[0].value += s;
-            }
-          }
-
-          cin.close ();
-
-          // Set the variable value and attributes. Note that we need to aquire
-          // unique lock before potentially changing the script's variable
-          // pool. The obtained variable reference can safelly be used with no
-          // locking as the variable pool is an associative container
-          // (underneath) and we are only adding new variables into it.
-          //
-          ulock ul (sp.root.var_pool_mutex);
-          const variable& var (sp.root.var_pool.insert (move (vname)));
-          ul.unlock ();
-
-          value& lhs (sp.assign (var));
-
-          // If there are no attributes specified then the variable assignment
-          // is straightforward. Otherwise we will use the build2 parser helper
-          // function.
-          //
-          if (ats == nullptr)
-            lhs.assign (move (ns), &var);
-          else
-          {
-            // If there is an error in the attributes string, our diagnostics
-            // will look like this:
-            //
-            // <attributes>:1:1 error: unknown value attribute x
-            //   testscript:10:1 info: while parsing attributes '[x]'
-            //
-            auto df = make_diag_frame (
-              [ats, &ll](const diag_record& dr)
-              {
-                dr << info (ll) << "while parsing attributes '" << *ats << "'";
-              });
-
-            parser p (sp.root.test_target.ctx);
-            p.apply_value_attributes (&var,
-                                      lhs,
-                                      value (move (ns)),
-                                      *ats,
-                                      token_type::assign,
-                                      path_name ("<attributes>"));
-          }
-        }
-        catch (const io_error& e)
-        {
-          fail (ll) << "set: " << e;
-        }
-        catch (const cli::exception& e)
-        {
-          fail (ll) << "set: " << e;
-        }
-      }
-
-      // Sorted array of builtins that support filesystem entries cleanup.
-      //
-      static const char* cleanup_builtins[] = {
-        "cp", "ln", "mkdir", "mv", "touch"};
-
-      static inline bool
-      cleanup_builtin (const string& name)
-      {
-        return binary_search (
-          cleanup_builtins,
-          cleanup_builtins +
-          sizeof (cleanup_builtins) / sizeof (*cleanup_builtins),
-          name);
-      }
-
-      static bool
-      run_pipe (scope& sp,
-                command_pipe::const_iterator bc,
-                command_pipe::const_iterator ec,
-                auto_fd ifd,
-                size_t ci, size_t li, const location& ll,
-                bool diag)
-      {
-        if (bc == ec) // End of the pipeline.
-          return true;
-
-        // The overall plan is to run the first command in the pipe, reading
-        // its input from the file descriptor passed (or, for the first
-        // command, according to stdin redirect specification) and redirecting
-        // its output to the right-hand part of the pipe recursively. Fail if
-        // the right-hand part fails. Otherwise check the process exit code,
-        // match stderr (and stdout for the last command in the pipe) according
-        // to redirect specification(s) and fail if any of the above fails.
-        //
-        const command& c (*bc);
-
-        // Register the command explicit cleanups. Verify that the path being
-        // cleaned up is a sub-path of the testscript working directory. Fail
-        // if this is not the case.
-        //
-        for (const auto& cl: c.cleanups)
-        {
-          const path& p (cl.path);
-          path np (normalize (p, sp, ll));
-
-          const string& ls (np.leaf ().string ());
-          bool wc (ls == "*" || ls == "**" || ls == "***");
-          const path& cp (wc ? np.directory () : np);
-          const dir_path& wd (sp.root.wd_path);
-
-          if (!cp.sub (wd))
-            fail (ll) << (wc
-                          ? "wildcard"
-                          : p.to_directory ()
-                            ? "directory"
-                            : "file")
-                      << " cleanup " << p << " is out of working directory "
-                      << wd;
-
-          sp.clean ({cl.type, move (np)}, false);
-        }
-
-        const redirect& in  (c.in.effective ());
-        const redirect& out (c.out.effective ());
-        const redirect& err (c.err.effective ());
-        bool eq (c.exit.comparison == exit_comparison::eq);
-
-        // If stdin file descriptor is not open then this is the first pipeline
-        // command.
-        //
-        bool first (ifd.get () == -1);
-
-        command_pipe::const_iterator nc (bc + 1);
-        bool last (nc == ec);
-
-        const string& program (c.program.string ());
-
-        // Prior to opening file descriptors for command input/output
-        // redirects let's check if the command is the exit builtin. Being a
-        // builtin syntactically it differs from the regular ones in a number
-        // of ways. It doesn't communicate with standard streams, so
-        // redirecting them is meaningless. It may appear only as a single
-        // command in a pipeline. It doesn't return any value and stops the
-        // scope execution, so checking its exit status is meaningless as
-        // well. That all means we can short-circuit here calling the builtin
-        // and bailing out right after that. Checking that the user didn't
-        // specify any redirects or exit code check sounds like a right thing
-        // to do.
-        //
-        if (program == "exit")
-        {
-          // In case the builtin is erroneously pipelined from the other
-          // command, we will close stdin gracefully (reading out the stream
-          // content), to make sure that the command doesn't print any
-          // unwanted diagnostics about IO operation failure.
-          //
-          // Note that dtor will ignore any errors (which is what we want).
-          //
-          ifdstream is (move (ifd), fdstream_mode::skip);
-
-          if (!first || !last)
-            fail (ll) << "exit builtin must be the only pipe command";
-
-          if (in.type != redirect_type::none)
-            fail (ll) << "exit builtin stdin cannot be redirected";
-
-          if (out.type != redirect_type::none)
-            fail (ll) << "exit builtin stdout cannot be redirected";
-
-          if (err.type != redirect_type::none)
-            fail (ll) << "exit builtin stderr cannot be redirected";
-
-          // We can't make sure that there is no exit code check. Let's, at
-          // least, check that non-zero code is not expected.
-          //
-          if (eq != (c.exit.code == 0))
-            fail (ll) << "exit builtin exit code cannot be non-zero";
-
-          exit_builtin (c.arguments, ll); // Throws exit_scope exception.
-        }
-
-        // Create a unique path for a command standard stream cache file.
-        //
-        auto std_path = [&sp, &ci, &li, &ll] (const char* n) -> path
-        {
-          path p (n);
-
-          // 0 if belongs to a single-line test scope, otherwise is the
-          // command line number (start from one) in the test scope.
-          //
-          if (li > 0)
-            p += "-" + to_string (li);
-
-          // 0 if belongs to a single-command expression, otherwise is the
-          // command number (start from one) in the expression.
-          //
-          // Note that the name like stdin-N can relate to N-th command of a
-          // single-line test or to N-th single-command line of multi-line
-          // test. These cases are mutually exclusive and so are unambiguous.
-          //
-          if (ci > 0)
-            p += "-" + to_string (ci);
-
-          return normalize (move (p), sp, ll);
-        };
-
-        // If this is the first pipeline command, then open stdin descriptor
-        // according to the redirect specified.
-        //
-        path isp;
-
-        if (!first)
-          assert (in.type == redirect_type::none); // No redirect expected.
-        else
-        {
-          // Open a file for passing to the command stdin.
-          //
-          auto open_stdin = [&isp, &ifd, &ll] ()
-          {
-            assert (!isp.empty ());
-
-            try
-            {
-              ifd = fdopen (isp, fdopen_mode::in);
-            }
-            catch (const io_error& e)
-            {
-              fail (ll) << "unable to read " << isp << ": " << e;
-            }
-          };
-
-          switch (in.type)
-          {
-          case redirect_type::pass:
-            {
-              try
-              {
-                ifd = fddup (0);
-              }
-              catch (const io_error& e)
-              {
-                fail (ll) << "unable to duplicate stdin: " << e;
-              }
-
-              break;
-            }
-
-          case redirect_type::none:
-            // Somehow need to make sure that the child process doesn't read
-            // from stdin. That is tricky to do in a portable way. Here we
-            // suppose that the program which (erroneously) tries to read some
-            // data from stdin being redirected to /dev/null fails not being
-            // able to read the expected data, and so the test doesn't pass
-            // through.
-            //
-            // @@ Obviously doesn't cover the case when the process reads
-            //    whatever available.
-            // @@ Another approach could be not to redirect stdin and let the
-            //    process to hang which can be interpreted as a test failure.
-            // @@ Both ways are quite ugly. Is there some better way to do
-            //    this?
-            //
-            // Fall through.
-            //
-          case redirect_type::null:
-            {
-              ifd = open_null ();
-              break;
-            }
-
-          case redirect_type::file:
-            {
-              isp = normalize (in.file.path, sp, ll);
-
-              open_stdin ();
-              break;
-            }
-
-          case redirect_type::here_str_literal:
-          case redirect_type::here_doc_literal:
-            {
-              // We could write to the command stdin directly but instead will
-              // cache the data for potential troubleshooting.
-              //
-              isp = std_path ("stdin");
-
-              save (
-                isp, transform (in.str, false, in.modifiers, sp.root), ll);
-
-              sp.clean_special (isp);
-
-              open_stdin ();
-              break;
-            }
-          case redirect_type::trace:
-          case redirect_type::merge:
-          case redirect_type::here_str_regex:
-          case redirect_type::here_doc_regex:
-          case redirect_type::here_doc_ref:   assert (false); break;
-          }
-        }
-
-        assert (ifd.get () != -1);
-
-        // Prior to opening file descriptors for command outputs redirects
-        // let's check if the command is the set builtin. Being a builtin
-        // syntactically it differs from the regular ones in a number of ways.
-        // It either succeeds or terminates abnormally, so redirecting stderr
-        // is meaningless. It also never produces any output and may appear
-        // only as a terminal command in a pipeline. That means we can
-        // short-circuit here calling the builtin and returning right after
-        // that. Checking that the user didn't specify any meaningless
-        // redirects or exit code check sounds as a right thing to do.
-        //
-        if (program == "set")
-        {
-          if (!last)
-            fail (ll) << "set builtin must be the last pipe command";
-
-          if (out.type != redirect_type::none)
-            fail (ll) << "set builtin stdout cannot be redirected";
-
-          if (err.type != redirect_type::none)
-            fail (ll) << "set builtin stderr cannot be redirected";
-
-          if (eq != (c.exit.code == 0))
-            fail (ll) << "set builtin exit code cannot be non-zero";
-
-          set_builtin (sp, c.arguments, move (ifd), ll);
-          return true;
-        }
-
-        // Open a file for command output redirect if requested explicitly
-        // (file overwrite/append redirects) or for the purpose of the output
-        // validation (none, here_*, file comparison redirects), register the
-        // file for cleanup, return the file descriptor. Interpret trace
-        // redirect according to the verbosity level (as null if below 2, as
-        // pass otherwise). Return nullfd, standard stream descriptor duplicate
-        // or null-device descriptor for merge, pass or null redirects
-        // respectively (not opening any file).
-        //
-        auto open = [&sp, &ll, &std_path] (const redirect& r,
-                                           int dfd,
-                                           path& p) -> auto_fd
-        {
-          assert (dfd == 1 || dfd == 2);
-          const char* what (dfd == 1 ? "stdout" : "stderr");
-
-          fdopen_mode m (fdopen_mode::out | fdopen_mode::create);
-
-          redirect_type rt (r.type != redirect_type::trace
-                            ? r.type
-                            : verb < 2
-                              ? redirect_type::null
-                              : redirect_type::pass);
-          switch (rt)
-          {
-          case redirect_type::pass:
-            {
-              try
-              {
-                return fddup (dfd);
-              }
-              catch (const io_error& e)
-              {
-                fail (ll) << "unable to duplicate " << what << ": " << e;
-              }
-            }
-
-          case redirect_type::null: return open_null ();
-
-            // Duplicate the paired file descriptor later.
-            //
-          case redirect_type::merge: return nullfd;
-
-          case redirect_type::file:
-            {
-              // For the cmp mode the user-provided path refers a content to
-              // match against, rather than a content to be produced (as for
-              // overwrite and append modes). And so for cmp mode we redirect
-              // the process output to a temporary file.
-              //
-              p = r.file.mode == redirect_fmode::compare
-                ? std_path (what)
-                : normalize (r.file.path, sp, ll);
-
-              m |= r.file.mode == redirect_fmode::append
-                ? fdopen_mode::at_end
-                : fdopen_mode::truncate;
-
-              break;
-            }
-
-          case redirect_type::none:
-          case redirect_type::here_str_literal:
-          case redirect_type::here_doc_literal:
-          case redirect_type::here_str_regex:
-          case redirect_type::here_doc_regex:
-            {
-              p = std_path (what);
-              m |= fdopen_mode::truncate;
-              break;
-            }
-
-          case redirect_type::trace:
-          case redirect_type::here_doc_ref: assert (false); break;
-          }
-
-          auto_fd fd;
-
-          try
-          {
-            fd = fdopen (p, m);
-
-            if ((m & fdopen_mode::at_end) != fdopen_mode::at_end)
-            {
-              if (rt == redirect_type::file)
-                sp.clean ({cleanup_type::always, p}, true);
-              else
-                sp.clean_special (p);
-            }
-          }
-          catch (const io_error& e)
-          {
-            fail (ll) << "unable to write to " << p << ": " << e;
-          }
-
-          return fd;
-        };
-
-        path osp;
-        fdpipe ofd;
-
-        // If this is the last command in the pipeline than redirect the
-        // command process stdout to a file. Otherwise create a pipe and
-        // redirect the stdout to the write-end of the pipe. The read-end will
-        // be passed as stdin for the next command in the pipeline.
-        //
-        // @@ Shouldn't we allow the here-* and file output redirects for a
-        //    command with pipelined output? Say if such redirect is present
-        //    then the process output is redirected to a file first (as it is
-        //    when no output pipelined), and only after the process exit code
-        //    and the output are validated the next command in the pipeline is
-        //    executed taking the file as an input. This could be usefull for
-        //    test failures investigation and for tests "tightening".
-        //
-        if (last)
-          ofd.out = open (out, 1, osp);
-        else
-        {
-          assert (out.type == redirect_type::none); // No redirect expected.
-          ofd = open_pipe ();
-        }
-
-        path esp;
-        auto_fd efd (open (err, 2, esp));
-
-        // Merge standard streams.
-        //
-        bool mo (out.type == redirect_type::merge);
-        if (mo || err.type == redirect_type::merge)
-        {
-          auto_fd& self  (mo ? ofd.out : efd);
-          auto_fd& other (mo ? efd : ofd.out);
-
-          try
-          {
-            assert (self.get () == -1 && other.get () != -1);
-            self = fddup (other.get ());
-          }
-          catch (const io_error& e)
-          {
-            fail (ll) << "unable to duplicate " << (mo ? "stderr" : "stdout")
-                      << ": " << e;
-          }
-        }
-
-        // All descriptors should be open to the date.
-        //
-        assert (ofd.out.get () != -1 && efd.get () != -1);
-
-        optional<process_exit> exit;
-        builtin_function* bf (builtins.find (program));
-
-        bool success;
-
-        auto process_args = [&c] () -> cstrings
-        {
-          cstrings args {c.program.string ().c_str ()};
-
-          for (const auto& a: c.arguments)
-            args.push_back (a.c_str ());
-
-          args.push_back (nullptr);
-          return args;
-        };
-
-        if (bf != nullptr)
-        {
-          // Execute the builtin.
-          //
-          if (verb >= 2)
-            print_process (process_args ());
-
-          // Some of the testscript builtins (cp, mkdir, etc) extend libbutl
-          // builtins (via callbacks) registering/moving cleanups for the
-          // filesystem entries they create/move, unless explicitly requested
-          // not to do so via the --no-cleanup option.
-          //
-          // Let's "wrap up" the cleanup-related flags into the single object
-          // to rely on "small function object" optimization.
-          //
-          struct cleanup
-          {
-            // Whether the cleanups are enabled for the builtin. Can be set to
-            // false by the parse_option callback if --no-cleanup is
-            // encountered.
-            //
-            bool enabled = true;
-
-            // Whether to register cleanup for a filesystem entry being
-            // created/updated depending on its existence. Calculated by the
-            // create pre-hook and used by the subsequent post-hook.
-            //
-            bool add;
-
-            // Whether to move existing cleanups for the filesystem entry
-            // being moved, rather than to erase them. Calculated by the move
-            // pre-hook and used by the subsequent post-hook.
-            //
-            bool move;
-          };
-
-          // nullopt if the builtin doesn't support cleanups.
-          //
-          optional<cleanup> cln;
-
-          if (cleanup_builtin (program))
-            cln = cleanup ();
-
-          builtin_callbacks bcs {
-
-            // create
-            //
-            // Unless cleanups are suppressed, test that the filesystem entry
-            // doesn't exist (pre-hook) and, if that's the case, register the
-            // cleanup for the newly created filesystem entry (post-hook).
-            //
-            [&sp, &cln] (const path& p, bool pre)
-            {
-              // Cleanups must be supported by a filesystem entry-creating
-              // builtin.
-              //
-              assert (cln);
-
-              if (cln->enabled)
-              {
-                if (pre)
-                  cln->add = !butl::entry_exists (p);
-                else if (cln->add)
-                  sp.clean ({cleanup_type::always, p}, true /* implicit */);
-              }
-            },
-
-            // move
-            //
-            // Validate the source and destination paths (pre-hook) and,
-            // unless suppressed, adjust the cleanups that are sub-paths of
-            // the source path (post-hook).
-            //
-            [&sp, &cln]
-            (const path& from, const path& to, bool force, bool pre)
-            {
-              // Cleanups must be supported by a filesystem entry-moving
-              // builtin.
-              //
-              assert (cln);
-
-              if (pre)
-              {
-                const dir_path&  wd (sp.wd_path);
-                const dir_path& rwd (sp.root.wd_path);
-
-                auto fail = [] (const string& d) {throw runtime_error (d);};
-
-                if (!from.sub (rwd) && !force)
-                  fail ("'" + from.representation () +
-                        "' is out of working directory '" + rwd.string () +
-                        "'");
-
-                auto check_wd = [&wd, fail] (const path& p)
-                {
-                  if (wd.sub (path_cast<dir_path> (p)))
-                    fail ("'" + p.string () +
-                          "' contains test working directory '" +
-                          wd.string () + "'");
-                };
-
-                check_wd (from);
-                check_wd (to);
-
-                // Unless cleanups are disabled, "move" the matching cleanups
-                // if the destination path doesn't exist and it is a sub-path
-                // of the working directory and just remove them otherwise.
-                //
-                if (cln->enabled)
-                  cln->move = !butl::entry_exists (to) && to.sub (rwd);
-              }
-              else if (cln->enabled)
-              {
-                // Move or remove the matching cleanups (see above).
-                //
-                // Note that it's not enough to just change the cleanup paths.
-                // We also need to make sure that these cleanups happen before
-                // the destination directory (or any of its parents) cleanup,
-                // that is potentially registered. To achieve that we can just
-                // relocate these cleanup entries to the end of the list,
-                // preserving their mutual order. Remember that cleanups in
-                // the list are executed in the reversed order.
-                //
-                cleanups cs;
-
-                // Remove the source path sub-path cleanups from the list,
-                // adjusting/caching them if required (see above).
-                //
-                for (auto i (sp.cleanups.begin ()); i != sp.cleanups.end (); )
-                {
-                  build2::test::script::cleanup& c (*i);
-                  path& p (c.path);
-
-                  if (p.sub (from))
-                  {
-                    if (cln->move)
-                    {
-                      // Note that we need to preserve the cleanup path
-                      // trailing separator which indicates the removal
-                      // method. Also note that leaf(), in particular, does
-                      // that.
-                      //
-                      p = p != from
-                        ? to / p.leaf (path_cast<dir_path> (from))
-                        : p.to_directory ()
-                        ? path_cast<dir_path> (to)
-                        : to;
-
-                      cs.push_back (move (c));
-                    }
-
-                    i = sp.cleanups.erase (i);
-                  }
-                  else
-                    ++i;
-                }
-
-                // Re-insert the adjusted cleanups at the end of the list.
-                //
-                sp.cleanups.insert (sp.cleanups.end (),
-                                    make_move_iterator (cs.begin ()),
-                                    make_move_iterator (cs.end ()));
-
-              }
-            },
-
-            // remove
-            //
-            // Validate the filesystem entry path (pre-hook).
-            //
-            [&sp] (const path& p, bool force, bool pre)
-            {
-              if (pre)
-              {
-                const dir_path&  wd (sp.wd_path);
-                const dir_path& rwd (sp.root.wd_path);
-
-                auto fail = [] (const string& d) {throw runtime_error (d);};
-
-                if (!p.sub (rwd) && !force)
-                  fail ("'" + p.representation () +
-                        "' is out of working directory '" + rwd.string () +
-                        "'");
-
-                if (wd.sub (path_cast<dir_path> (p)))
-                  fail ("'" + p.string () +
-                        "' contains test working directory '" + wd.string () +
-                        "'");
-              }
-            },
-
-            // parse_option
-            //
-            [&cln] (const strings& args, size_t i)
-            {
-              // Parse --no-cleanup, if it is supported by the builtin.
-              //
-              if (cln && args[i] == "--no-cleanup")
-              {
-                cln->enabled = false;
-                return 1;
-              }
-
-              return 0;
-            },
-
-            // sleep
-            //
-            // Deactivate the thread before going to sleep.
-            //
-            [&sp] (const duration& d)
-            {
-              // If/when required we could probably support the precise sleep
-              // mode (e.g., via an option).
-              //
-              sp.root.test_target.ctx.sched.sleep (d);
-            }
-          };
-
-          try
-          {
-            uint8_t r; // Storage.
-            builtin b (bf (r,
-                           c.arguments,
-                           move (ifd), move (ofd.out), move (efd),
-                           sp.wd_path,
-                           bcs));
-
-            success = run_pipe (sp,
-                                nc,
-                                ec,
-                                move (ofd.in),
-                                ci + 1, li, ll, diag);
-
-            exit = process_exit (b.wait ());
-          }
-          catch (const system_error& e)
-          {
-            fail (ll) << "unable to execute " << c.program << " builtin: "
-                      << e << endf;
-          }
-        }
-        else
-        {
-          // Execute the process.
-          //
-          cstrings args (process_args ());
-
-          // Resolve the relative not simple program path against the scope's
-          // working directory. The simple one will be left for the process
-          // path search machinery. Also strip the potential leading `^`,
-          // indicating that this is an external program rather than a
-          // builtin.
-          //
-          path p;
-
-          try
-          {
-            p = path (args[0]);
-
-            if (p.relative ())
-            {
-              auto program = [&p, &args] (path pp)
-              {
-                p = move (pp);
-                args[0] = p.string ().c_str ();
-              };
-
-              if (p.simple ())
-              {
-                const string& s (p.string ());
-
-                // Don't end up with an empty path.
-                //
-                if (s.size () > 1 && s[0] == '^')
-                  program (path (s, 1, s.size () - 1));
-              }
-              else
-                program (sp.wd_path / p);
-            }
-          }
-          catch (const invalid_path& e)
-          {
-            fail (ll) << "invalid program path " << e.path;
-          }
-
-          try
-          {
-            process_path pp (process::path_search (args[0]));
-
-            // Note: the builtin-escaping character '^' is not printed.
-            //
-            if (verb >= 2)
-              print_process (args);
-
-            process pr (
-              pp,
-              args.data (),
-              {ifd.get (), -1}, process::pipe (ofd), {-1, efd.get ()},
-              sp.wd_path.string ().c_str ());
-
-            ifd.reset ();
-            ofd.out.reset ();
-            efd.reset ();
-
-            success = run_pipe (sp,
-                                nc,
-                                ec,
-                                move (ofd.in),
-                                ci + 1, li, ll, diag);
-
-            pr.wait ();
-
-            exit = move (pr.exit);
-          }
-          catch (const process_error& e)
-          {
-            error (ll) << "unable to execute " << args[0] << ": " << e;
-
-            if (e.child)
-              std::exit (1);
-
-            throw failed ();
-          }
-        }
-
-        assert (exit);
-
-        // If the righ-hand side pipeline failed than the whole pipeline fails,
-        // and no further checks are required.
-        //
-        if (!success)
-          return false;
-
-        const path& pr (c.program);
-
-        // If there is no valid exit code available by whatever reason then we
-        // print the proper diagnostics, dump stderr (if cached and not too
-        // large) and fail the whole test. Otherwise if the exit code is not
-        // correct then we print diagnostics if requested and fail the
-        // pipeline.
-        //
-        bool valid (exit->normal ());
-
-        // On Windows the exit code can be out of the valid codes range being
-        // defined as uint16_t.
-        //
-#ifdef _WIN32
-        if (valid)
-          valid = exit->code () < 256;
-#endif
-
-        success = valid && eq == (exit->code () == c.exit.code);
-
-        if (!valid || (!success && diag))
-        {
-          // In the presense of a valid exit code we print the diagnostics and
-          // return false rather than throw.
-          //
-          diag_record d (valid ? error (ll) : fail (ll));
-
-          if (!exit->normal ())
-            d << pr << " " << *exit;
-          else
-          {
-            uint16_t ec (exit->code ()); // Make sure is printed as integer.
-
-            if (!valid)
-              d << pr << " exit code " << ec << " out of 0-255 range";
-            else if (!success)
-            {
-              if (diag)
-                d << pr << " exit code " << ec << (eq ? " != " : " == ")
-                  << static_cast<uint16_t> (c.exit.code);
-            }
-            else
-              assert (false);
-          }
-
-          if (non_empty (esp, ll))
-            d << info << "stderr: " << esp;
-
-          if (non_empty (osp, ll))
-            d << info << "stdout: " << osp;
-
-          if (non_empty (isp, ll))
-            d << info << "stdin: " << isp;
-
-          // Print cached stderr.
-          //
-          print_file (d, esp, ll);
-        }
-
-        // If exit code is correct then check if the standard outputs match the
-        // expectations. Note that stdout is only redirected to file for the
-        // last command in the pipeline.
-        //
-        // The thinking behind matching stderr first is that if it mismatches,
-        // then the program probably misbehaves (executes wrong functionality,
-        // etc) in which case its stdout doesn't really matter.
-        //
-        if (success)
-          success =
-            check_output (pr, esp, isp, err, ll, sp, diag, "stderr") &&
-            (!last ||
-             check_output (pr, osp, isp, out, ll, sp, diag, "stdout"));
-
-        return success;
-      }
-
-      static bool
-      run_expr (scope& sp,
-                const command_expr& expr,
-                size_t li, const location& ll,
-                bool diag)
-      {
-        // Print test id once per test expression.
-        //
-        auto df = make_diag_frame (
-          [&sp](const diag_record& dr)
-          {
-            // Let's not depend on how the path representation can be improved
-            // for readability on printing.
-            //
-            dr << info << "test id: " << sp.id_path.posix_string ();
-          });
-
-        // Commands are numbered sequentially throughout the expression
-        // starting with 1. Number 0 means the command is a single one.
-        //
-        size_t ci (expr.size () == 1 && expr.back ().pipe.size () == 1
-                   ? 0
-                   : 1);
-
-        // If there is no ORs to the right of a pipe then the pipe failure is
-        // fatal for the whole expression. In particular, the pipe must print
-        // the diagnostics on failure (if generally allowed). So we find the
-        // pipe that "switches on" the diagnostics potential printing.
-        //
-        command_expr::const_iterator trailing_ands; // Undefined if diag is
-                                                    // disallowed.
-        if (diag)
-        {
-          auto i (expr.crbegin ());
-          for (; i != expr.crend () && i->op == expr_operator::log_and; ++i) ;
-          trailing_ands = i.base ();
-        }
-
-        bool r (false);
-        bool print (false);
-
-        for (auto b (expr.cbegin ()), i (b), e (expr.cend ()); i != e; ++i)
-        {
-          if (diag && i + 1 == trailing_ands)
-            print = true;
-
-          const command_pipe& p (i->pipe);
-          bool or_op (i->op == expr_operator::log_or);
-
-          // Short-circuit if the pipe result must be OR-ed with true or AND-ed
-          // with false.
-          //
-          if (!((or_op && r) || (!or_op && !r)))
-            r = run_pipe (
-              sp, p.begin (), p.end (), auto_fd (), ci, li, ll, print);
-
-          ci += p.size ();
-        }
-
-        return r;
+                            ? *sp.parent->work_dir.path
+                            : sp.work_dir.path->directory ());
       }
 
       void default_runner::
       run (scope& sp,
            const command_expr& expr, command_type ct,
-           size_t li,
-           const location& ll)
+           size_t li, const location& ll)
       {
         // Noop for teardown commands if keeping tests output is requested.
         //
@@ -2085,8 +144,18 @@ namespace build2
           text << ": " << c << expr;
         }
 
-        if (!run_expr (sp, expr, li, ll, true))
-          throw failed (); // Assume diagnostics is already printed.
+        // Print test id once per test expression.
+        //
+        auto df = make_diag_frame (
+          [&sp](const diag_record& dr)
+          {
+            // Let's not depend on how the path representation can be improved
+            // for readability on printing.
+            //
+            dr << info << "test id: " << sp.id_path.posix_string ();
+          });
+
+        build2::script::run (sp, expr, li, ll);
       }
 
       bool default_runner::
@@ -2097,7 +166,18 @@ namespace build2
         if (verb >= 3)
           text << ": ?" << expr;
 
-        return run_expr (sp, expr, li, ll, false);
+        // Print test id once per test expression.
+        //
+        auto df = make_diag_frame (
+          [&sp](const diag_record& dr)
+          {
+            // Let's not depend on how the path representation can be improved
+            // for readability on printing.
+            //
+            dr << info << "test id: " << sp.id_path.posix_string ();
+          });
+
+        return build2::script::run_if (sp, expr, li, ll);
       }
     }
   }