* Replaced quite a lot of unnecessary size() calls on STL containers

   with the more describtive and faster empty() method.

HACKING

@@ -354,7 +354,7 @@ An invariant failure indicates that there is a bug in monotone.  e.g.
 User naughtiness handles error conditions where the user has asked monotone
 to do something it is unable to.  e.g.
 
-    N(completions.size() != 0,
+    N(!completions.empty(),
         F("no match for selection '%s'") % str);
 
 Error conditions handle most other error cases, where monotone is unable to

NEWS

@@ -17,6 +17,10 @@
             would reinitialize the database. This was rather slow, so
             monotone will now keep the database open between commands.
 
+        - Small performance gains especially for annotate by replacing
+          'size() == 0' and similar checks with the faster 'empty()'
+          STL method.
+
         New features
 
         - New 'mtn ls duplicates' command which lets you list

asciik.cc

@@ -245,7 +245,7 @@ asciik::draw(size_t const curr_items,
   if (num_lines < 2)
     lines.push_back(string(""));
   // ignore empty lines at the end
-  while ((num_lines > 2) && (lines[num_lines - 1].size() == 0))
+  while ((num_lines > 2) && (lines[num_lines - 1].empty()))
     --num_lines;
 
   // prints it out
@@ -314,7 +314,7 @@ asciik::try_draw(vector<revision_id> const & next_row,
     preservation_crosses.begin(), preservation_crosses.end(),
     parent_crosses.begin(), parent_crosses.end(),
     insert_iterator<set<size_t> >(intersection_crosses, intersection_crosses.begin()));
-  if (intersection_crosses.size() > 0)
+  if (!intersection_crosses.empty())
     return false;
 
   set<pair<size_t, size_t> > links(preservation_links);
@@ -360,7 +360,7 @@ asciik::print(revision_id const & rev,
     curr_row = no_ghost;
   else if (try_draw(next_row, curr_loc, parents, annotation))
     curr_row = next_row;
-  else if (new_revs.size() == 0) // this line has disappeared
+  else if (new_revs.empty()) // this line has disappeared
     {
       vector<revision_id> extra_ghost(next_row);
       I(curr_loc < extra_ghost.size());

automate.cc

@@ -966,7 +966,7 @@ inventory_determine_changes(inventory_item const & item, roster_t const & old_ro
       if (item.new_node.type == path::file)
         changes.push_back("content");
 
-      if (item.new_node.attrs.size() > 0)
+      if (!item.new_node.attrs.empty())
         changes.push_back("attrs");
     }
 }
@@ -2150,7 +2150,7 @@ CMD_AUTOMATE(get_db_variables, N_("[DOMAIN]"),
       if (cur_domain != i->first.first)
         {
           // check if we need to print a previous stanza
-          if (st.entries.size() > 0)
+          if (!st.entries.empty())
             {
               pr.print_stanza(st);
               st.entries.clear();

cert.cc

@@ -409,7 +409,7 @@ guess_branch(options & opts, project_t & project,
       set<branch_name> branches;
       project.get_revision_branches(ident, branches);
 
-      N(branches.size() != 0,
+      N(!branches.empty(),
         F("no branch certs found for revision %s, "
           "please provide a branch name") % ident);
 

cmd_automate.cc

@@ -87,7 +87,7 @@ CMD_AUTOMATE(interface_version, "",
              "",
              options::opts::none)
 {
-  N(args.size() == 0,
+  N(args.empty(),
     F("no arguments needed"));
 
   output << interface_version << '\n';
@@ -343,7 +343,7 @@ CMD_AUTOMATE(stdio, "",
              "",
              options::opts::automate_stdio_size)
 {
-  N(args.size() == 0,
+  N(args.empty(),
     F("no arguments needed"));
 
   database db(app);
@@ -384,7 +384,7 @@ CMD_AUTOMATE(stdio, "",
               set< command_id > matches =
                 CMD_REF(automate)->complete_command(id);
 
-              if (matches.size() == 0)
+              if (matches.empty())
                 {
                   N(false, F("no completions for this command"));
                 }
@@ -475,7 +475,7 @@ LUAEXT(mtn_automate, )
       set< commands::command_id > matches =
         CMD_REF(automate)->complete_command(id);
 
-      if (matches.size() == 0)
+      if (matches.empty())
         {
           N(false, F("no completions for this command"));
         }

cmd_diff_log.cc

@@ -365,7 +365,7 @@ prepare_diff(app_state & app,
   N(app.opts.revision_selectors.size() <= 2,
     F("more than two revisions given"));
 
-  if (app.opts.revision_selectors.size() == 0)
+  if (app.opts.revision_selectors.empty())
     {
       roster_t old_roster, restricted_roster, new_roster;
       revision_id old_rid;
@@ -509,7 +509,7 @@ CMD(diff, "diff", "di", CMD_REF(informative), N_("[PATH]..."),
   vector<string> lines;
   split_into_lines(summary(), lines);
   cout << "#\n";
-  if (summary().size() > 0)
+  if (!summary().empty())
     {
       cout << revs << "#\n";
       for (vector<string>::iterator i = lines.begin();
@@ -644,7 +644,7 @@ CMD(log, "log", "", CMD_REF(informative), N_("[FILE] ..."),
   frontier_t frontier(rev_cmp(!(next>0)));
   revision_id first_rid; // for mapping paths to node ids when restricted
 
-  if (app.opts.from.size() == 0)
+  if (app.opts.from.empty())
     {
       workspace work(app,
                      F("try passing a --from revision to start at"));
@@ -680,10 +680,10 @@ CMD(log, "log", "", CMD_REF(informative), N_("[FILE] ..."),
 
   node_restriction mask;
 
-  if (args.size() > 0)
+  if (!args.empty())
     {
       // User wants to trace only specific files
-      if (app.opts.from.size() == 0)
+      if (app.opts.from.empty())
         {
           workspace work(app);
           roster_t new_roster;

cmd_files.cc

@@ -146,7 +146,7 @@ CMD(annotate, "annotate", "", CMD_REF(informative), N_("PATH"),
   L(FL("annotate file '%s'") % file);
 
   roster_t roster;
-  if (app.opts.revision_selectors.size() == 0)
+  if (app.opts.revision_selectors.empty())
     {
       // What this _should_ do is calculate the current workspace roster
       // and/or revision and hand that to do_annotate.  This should just
@@ -198,19 +198,15 @@ CMD(identify, "identify", "", CMD_REF(debug), N_("[PATH]"),
        "one from the standard input is calculated."),
     options::opts::none)
 {
-  if (!(args.size() == 0 || args.size() == 1))
+  if (args.size() > 1)
     throw usage(execid);
 
   data dat;
 
-  if (args.size() == 1)
-    {
-      read_data_for_command_line(idx(args, 0), dat);
-    }
+  if (args.empty())
+    read_data_stdin(dat);
   else
-    {
-      read_data_stdin(dat);
-    }
+    read_data_for_command_line(idx(args, 0), dat);
 
   id ident;
   calculate_ident(dat, ident);
@@ -296,7 +292,7 @@ CMD(cat, "cat", "", CMD_REF(informative),
 
   database db(app);
   revision_id rid;
-  if (app.opts.revision_selectors.size() == 0)
+  if (app.opts.revision_selectors.empty())
     {
       workspace work(app);
       parent_map parents;
@@ -363,7 +359,7 @@ CMD_AUTOMATE(get_file_of, N_("FILENAME"),
   database db(app);
 
   revision_id rid;
-  if (app.opts.revision_selectors.size() == 0)
+  if (app.opts.revision_selectors.empty())
     {
       workspace work(app);
 

cmd_key_cert.cc

@@ -122,7 +122,7 @@ CMD(ssh_agent_export, "ssh_agent_export", "", CMD_REF(key_and_cert),
   rsa_keypair_id id;
   get_user_key(app.opts, app.lua, db, keys, id);
 
-  if (args.size() == 0)
+  if (args.empty())
     keys.export_key_for_agent(id, cout);
   else
     {

cmd_list.cc

@@ -136,7 +136,7 @@ CMD(certs, "certs", "", CMD_REF(list), "ID",
 
       vector<string> lines;
       split_into_lines(washed, lines);
-      std::string value_first_line = lines.size() > 0 ? idx(lines, 0) : "";
+      std::string value_first_line = lines.empty() ? "" : idx(lines, 0);
 
       cout << string(guess_terminal_width(), '-') << '\n'
            << (i18n_format(str)
@@ -149,7 +149,7 @@ CMD(certs, "certs", "", CMD_REF(list), "ID",
         cout << (i18n_format(extra_str) % idx(lines, i));
     }
 
-  if (certs.size() > 0)
+  if (!certs.empty())
     cout << '\n';
 
   guard.commit();
@@ -161,7 +161,7 @@ CMD(duplicates, "duplicates", "", CMD_REF(list), "",
     "",
     options::opts::revision)
 {
-  if (args.size() != 0)
+  if (!args.empty())
     throw usage(execid);
 
   revision_id rev_id;
@@ -172,7 +172,7 @@ CMD(duplicates, "duplicates", "", CMD_REF(list), "",
   N(app.opts.revision_selectors.size() <= 1,
     F("more than one revision given"));
 
-  if (app.opts.revision_selectors.size() == 0)
+  if (app.opts.revision_selectors.empty())
     {
       workspace work(app);
       temp_node_id_source nis;
@@ -302,7 +302,7 @@ CMD(keys, "keys", "", CMD_REF(list), "[PATTERN]",
         }
     }
 
-  if (pubkeys.size() > 0)
+  if (!pubkeys.empty())
     {
       cout << "\n[public keys]\n";
       for (map<rsa_keypair_id, bool>::iterator i = pubkeys.begin();
@@ -333,7 +333,7 @@ CMD(keys, "keys", "", CMD_REF(list), "[PATTERN]",
       cout << '\n';
     }
 
-  if (privkeys.size() > 0)
+  if (!privkeys.empty())
     {
       cout << "\n[private keys]\n";
       for (vector<rsa_keypair_id>::iterator i = privkeys.begin();
@@ -358,10 +358,9 @@ CMD(keys, "keys", "", CMD_REF(list), "[PATTERN]",
         }
     }
 
-  if (pubkeys.size() == 0 &&
-      privkeys.size() == 0)
+  if (pubkeys.empty() && privkeys.empty())
     {
-      if (args.size() == 0)
+      if (args.empty())
         P(F("no keys found"));
       else
         W(F("no keys found matching '%s'") % idx(args, 0)());
@@ -400,7 +399,7 @@ CMD(epochs, "epochs", "", CMD_REF(list), "[BRANCH [...]]",
   map<branch_name, epoch_data> epochs;
   db.get_epochs(epochs);
 
-  if (args.size() == 0)
+  if (args.empty())
     {
       for (map<branch_name, epoch_data>::const_iterator
              i = epochs.begin();
@@ -447,7 +446,7 @@ CMD(vars, "vars", "", CMD_REF(list), "[DOMAIN]",
 {
   bool filterp;
   var_domain filter;
-  if (args.size() == 0)
+  if (args.empty())
     {
       filterp = false;
     }
@@ -678,7 +677,7 @@ CMD_AUTOMATE(keys, "",
              "",
              options::opts::none)
 {
-  N(args.size() == 0,
+  N(args.empty(),
     F("no arguments needed"));
 
   database db(app);