summary refs log tree commit diff stats
path: root/doc/pydoc
Commit message (Collapse)AuthorAgeFilesLines
* rebuilt pydochut2010-03-3118-65/+188
|
* updated TODO and pydochut2010-03-2120-52/+85
|
* incremented verison number v1.0.4hut2010-03-121-2/+2
|
* updated pydochut2010-03-1217-161/+33
|
* updated pydochut2010-03-1270-3946/+816
|
* incremented version number and updated pydoc html files v1.0.3hut2010-02-1675-1972/+1415
|
* 1.0.2! v1.0.2hut2010-01-1430-84/+116
|
* updated pydoc documentationhut2010-01-1361-846/+795
|
* new minor version v1.0.1hut2010-01-022-4/+4
|
* updated pydoc documentationhut2010-01-0248-788/+3167
|
* moved pydoc pages to doc/pydochut2009-12-2565-0/+10505
199'>199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489
//: The goal of this skeleton is to make programs more easy to understand and
//: more malleable, easy to rewrite in radical ways without accidentally
//: breaking some corner case. Tests further both goals. They help
//: understandability by letting one make small changes and get feedback. What
//: if I wrote this line like so? What if I removed this function call, is it
//: really necessary? Just try it, see if the tests pass. Want to explore
//: rewriting this bit in this way? Tests put many refactorings on a firmer
//: footing.
//:
//: But the usual way we write tests seems incomplete. Refactorings tend to
//: work in the small, but don't help with changes to function boundaries. If
//: you want to extract a new function you have to manually test-drive it to
//: create tests for it. If you want to inline a function its tests are no
//: longer valid. In both cases you end up having to reorganize code as well as
//: tests, an error-prone activity.
//:
//: This file tries to fix this problem by supporting domain-driven testing
//: We try to focus on the domain of inputs the program should work on. All
//: tests invoke the program in a single way: by calling run() with different
//: inputs. The program operates on the input and logs _facts_ it deduces to a
//: trace:
//:   trace("label") << "fact 1: " << val;
//:
//: The tests check for facts:
//:   :(scenario foo)
//:   34  # call run() with this input
//:   +label: fact 1: 34  # trace should have logged this at the end
//:   -label: fact 1: 35  # trace should never contain such a line
//:
//: Since we never call anything but the run() function directly, we never have
//: to rewrite the tests when we reorganize the internals of the program. We
//: just have to make sure our rewrite deduces the same facts about the domain,
//: and that's something we're going to have to do anyway.
//:
//: To avoid the combinatorial explosion of integration tests, we organize the
//: program into different layers, and each fact is logged to the trace with a
//: specific label. Individual tests can focus on specific labels. In essence,
//: validating the facts logged with a specific label is identical to calling
//: some internal subsystem.
//:
//: Traces interact salubriously with layers. Thanks to our ordering
//: directives, each layer can contain its own tests. They may rely on other
//: layers, but when a test fails its usually due to breakage in the same
//: layer. When multiple tests fail, it's usually useful to debug the very
//: first test to fail. This is in contrast with the traditional approach,
//: where changes can cause breakages in faraway subsystems, and picking the
//: right test to debug can be an important skill to pick up.
//:
//: A final wrinkle is for recursive functions; it's often useful to segment
//: calls of different depth in the trace:
//:   +eval/1: => 34  # the topmost call to eval should have logged this line
//: (look at new_trace_frame below)
//:
//: To build robust tests, trace facts about your domain rather than details of
//: how you computed them.
//:
//: More details: http://akkartik.name/blog/tracing-tests
//:
//: ---
//:
//: Between layers and domain-driven testing, programming starts to look like a
//: fundamentally different activity. Instead of a) superficial, b) local rules
//: on c) code [like http://blog.bbv.ch/2013/06/05/clean-code-cheat-sheet],
//: we allow programmers to engage with the a) deep, b) global structure of the
//: c) domain. If you can systematically track discontinuities in the domain
//: you don't care if the code used gotos as long as it passed the tests. If
//: tests become more robust to run it becomes easier to try out radically
//: different implementations for the same program. If code is super-easy to
//: rewrite, it becomes less important what indentation style it uses, or that
//: the objects are appropriately encapsulated, or that the functions are
//: referentially transparent.
//:
//: Instead of plumbing, programming becomes building and gradually refining a
//: map of the environment the program must operate under. Whether a program is
//: 'correct' at a given point in time is a red herring; what matters is
//: avoiding regression by monotonically nailing down the more 'eventful' parts
//: of the terrain. It helps readers new and old and rewards curiosity to
//: organize large programs in self-similar hiearchies of example scenarios
//: colocated with the code that makes them work.
//:
//:   "Programming properly should be regarded as an activity by which
//:   programmers form a mental model, rather than as production of a program."
//:   -- Peter Naur (http://alistair.cockburn.us/ASD+book+extract%3A+%22Naur,+Ehn,+Musashi%22)

:(before "int main")
// End Tracing  // hack to ensure most code in this layer comes before anything else

:(before "End Tracing")
bool Hide_warnings = false;
:(before "End Setup")
Hide_warnings = false;

:(before "End Tracing")
struct trace_stream {
  vector<pair<string, pair<int, string> > > past_lines;  // [(layer label, frame, line)]
  unordered_map<string, int> frame;
  // accumulator for current line
  ostringstream* curr_stream;
  string curr_layer;
  string dump_layer;
  trace_stream() :curr_stream(NULL) {}
  ~trace_stream() { if (curr_stream) delete curr_stream; }

  ostringstream& stream(string layer) {
    newline();
    curr_stream = new ostringstream;
    curr_layer = layer;
    return *curr_stream;
  }

  // be sure to call this before messing with curr_stream or curr_layer or frame
  void newline() {
    if (!curr_stream) return;
    past_lines.push_back(pair<string, pair<int, string> >(curr_layer, pair<int, string>(frame[curr_layer], curr_stream->str())));
    if (curr_layer == dump_layer || curr_layer == "dump" || dump_layer == "all" ||
        (!Hide_warnings && curr_layer == "warn"))
      cerr << frame[curr_layer] << ": " << with_newline(curr_stream->str());
    delete curr_stream;
    curr_stream = NULL;
  }

  // Useful for debugging.
  string readable_contents(string layer) {  // missing layer = everything, frame, hierarchical layers
    newline();
    ostringstream output;
    string real_layer, frame;
    parse_layer_and_frame(layer, &real_layer, &frame);
    for (vector<pair<string, pair<int, string> > >::iterator p = past_lines.begin(); p != past_lines.end(); ++p)
      if (layer.empty() || prefix_match(real_layer, p->first))
        output << p->first << "/" << p->second.first << ": " << with_newline(p->second.second);
    return output.str();
  }

  // Useful for a newcomer to visualize the program at work.
  void dump_browseable_contents(string layer) {
    ofstream dump("dump");
    dump << "<div class='frame' frame_index='1'>start</div>\n";
    for (vector<pair<string, pair<int, string> > >::iterator p = past_lines.begin(); p != past_lines.end(); ++p) {
      if (p->first != layer) continue;
      dump << "<div class='frame";
      if (p->second.first > 1) dump << " hidden";
      dump << "' frame_index='" << p->second.first << "'>";
      dump << p->second.second;
      dump << "</div>\n";
    }
    dump.close();
  }

  string with_newline(string s) {
    if (s[s.size()-1] != '\n') return s+'\n';
    return s;
  }
};



trace_stream* Trace_stream = NULL;

// Top-level helper. IMPORTANT: can't nest.
#define trace(layer)  !Trace_stream ? cerr /*print nothing*/ : Trace_stream->stream(layer)
// Warnings should go straight to cerr by default since calls to trace() have
// some unfriendly constraints (they delay printing, they can't nest)
#define raise  ((!Trace_stream || !Hide_warnings) ? cerr /*do print*/ : Trace_stream->stream("warn")) << __FILE__ << ":" << __LINE__ << " "

// A separate helper for debugging. We should only trace domain-specific
// facts. For everything else use log.
#define xlog if (false) log
// To turn on logging replace 'xlog' with 'log'.
#define log cerr

:(before "End Types")
// raise << die exits after printing -- unless Hide_warnings is set.
struct die {};
:(before "End Tracing")
ostream& operator<<(ostream& os, unused die) {
  if (Hide_warnings) return os;
  os << "dying";
  if (Trace_stream) Trace_stream->newline();
  exit(1);
}

#define CLEAR_TRACE  delete Trace_stream, Trace_stream = new trace_stream;

#define DUMP(layer)  if (Trace_stream) cerr << Trace_stream->readable_contents(layer);

// Trace_stream is a resource, lease_tracer uses RAII to manage it.
string Trace_file;
static string Trace_dir = ".traces/";
struct lease_tracer {
  lease_tracer() { Trace_stream = new trace_stream; }
  ~lease_tracer() {
//?     cerr << "write to file? " << Trace_file << "$\n"; //? 2
    if (!Trace_file.empty()) {
//?       cerr << "writing\n"; //? 2
      ofstream fout((Trace_dir+Trace_file).c_str());
      fout << Trace_stream->readable_contents("");
      fout.close();
    }
    delete Trace_stream, Trace_stream = NULL, Trace_file = "";
  }
};

#define START_TRACING_UNTIL_END_OF_SCOPE  lease_tracer leased_tracer;
:(before "End Test Setup")
  START_TRACING_UNTIL_END_OF_SCOPE
//?   Trace_stream->dump_layer = "all"; //? 1

:(before "End Tracing")
void trace_all(const string& label, const list<string>& in) {
  for (list<string>::const_iterator p = in.begin(); p != in.end(); ++p)
    trace(label) << *p;
}

bool check_trace_contents(string FUNCTION, string FILE, int LINE, string expected) {  // missing layer == anywhere, frame, hierarchical layers
  vector<string> expected_lines = split(expected, "");
  size_t curr_expected_line = 0;
  while (curr_expected_line < expected_lines.size() && expected_lines[curr_expected_line].empty())
    ++curr_expected_line;
  if (curr_expected_line == expected_lines.size()) return true;
  Trace_stream->newline();
  ostringstream output;
  string layer, frame, contents;
  parse_layer_frame_contents(expected_lines[curr_expected_line], &layer, &frame, &contents);
  for (vector<pair<string, pair<int, string> > >::iterator p = Trace_stream->past_lines.begin(); p != Trace_stream->past_lines.end(); ++p) {
    if (!layer.empty() && !prefix_match(layer, p->first))
      continue;

    if (!frame.empty() && strtol(frame.c_str(), NULL, 0) != p->second.first)
      continue;

    if (contents != p->second.second)
      continue;

    ++curr_expected_line;
    while (curr_expected_line < expected_lines.size() && expected_lines[curr_expected_line].empty())
      ++curr_expected_line;
    if (curr_expected_line == expected_lines.size()) return true;
    parse_layer_frame_contents(expected_lines[curr_expected_line], &layer, &frame, &contents);
  }

  ++Num_failures;
  cerr << "\nF " << FUNCTION << "(" << FILE << ":" << LINE << "): missing [" << contents << "] in trace:\n";
  DUMP(layer);
  Passed = false;
  return false;
}

void parse_layer_frame_contents(const string& orig, string* layer, string* frame, string* contents) {
  string layer_and_frame;
  parse_contents(orig, ": ", &layer_and_frame, contents);
  parse_layer_and_frame(layer_and_frame, layer, frame);
}

void parse_contents(const string& s, const string& delim, string* prefix, string* contents) {
  string::size_type pos = s.find(delim);
  if (pos == NOT_FOUND) {
    *prefix = "";
    *contents = s;
  }
  else {
    *prefix = s.substr(0, pos);
    *contents = s.substr(pos+delim.size());
  }
}

void parse_layer_and_frame(const string& orig, string* layer, string* frame) {
  size_t last_slash = orig.rfind('/');
  if (last_slash == NOT_FOUND
      || orig.find_last_not_of("0123456789") != last_slash) {
    *layer = orig;
    *frame = "";
  }
  else {
    *layer = orig.substr(0, last_slash);
    *frame = orig.substr(last_slash+1);
  }
}



bool check_trace_contents(string FUNCTION, string FILE, int LINE, string layer, string expected) {  // empty layer == everything, multiple layers, hierarchical layers
  vector<string> expected_lines = split(expected, "");
  size_t curr_expected_line = 0;
  while (curr_expected_line < expected_lines.size() && expected_lines[curr_expected_line].empty())
    ++curr_expected_line;
  if (curr_expected_line == expected_lines.size()) return true;
  Trace_stream->newline();
  ostringstream output;
  vector<string> layers = split(layer, ",");
  for (vector<pair<string, pair<int, string> > >::iterator p = Trace_stream->past_lines.begin(); p != Trace_stream->past_lines.end(); ++p) {
    if (!layer.empty() && !any_prefix_match(layers, p->first))
      continue;
    if (p->second.second != expected_lines[curr_expected_line])
      continue;
    ++curr_expected_line;
    while (curr_expected_line < expected_lines.size() && expected_lines[curr_expected_line].empty())
      ++curr_expected_line;
    if (curr_expected_line == expected_lines.size()) return true;
  }

  ++Num_failures;
  cerr << "\nF " << FUNCTION << "(" << FILE << ":" << LINE << "): missing [" << expected_lines[curr_expected_line] << "] in trace:\n";
  DUMP(layer);
  Passed = false;
  return false;
}

#define CHECK_TRACE_CONTENTS(...)  check_trace_contents(__FUNCTION__, __FILE__, __LINE__, __VA_ARGS__)

int trace_count(string layer) {
  return trace_count(layer, "");
}

int trace_count(string layer, string line) {
  Trace_stream->newline();
  long result = 0;
  vector<string> layers = split(layer, ",");
  for (vector<pair<string, pair<int, string> > >::iterator p = Trace_stream->past_lines.begin(); p != Trace_stream->past_lines.end(); ++p) {
    if (any_prefix_match(layers, p->first))
      if (line == "" || p->second.second == line)
        ++result;
  }
  return result;
}

int trace_count(string layer, int frame, string line) {
  Trace_stream->newline();
  long result = 0;
  vector<string> layers = split(layer, ",");
  for (vector<pair<string, pair<int, string> > >::iterator p = Trace_stream->past_lines.begin(); p != Trace_stream->past_lines.end(); ++p) {
    if (any_prefix_match(layers, p->first) && p->second.first == frame)
      if (line == "" || p->second.second == line)
        ++result;
  }
  return result;
}

#define CHECK_TRACE_WARNS()  CHECK(trace_count("warn") > 0)
#define CHECK_TRACE_DOESNT_WARN() \
  if (trace_count("warn") > 0) { \
    ++Num_failures; \
    cerr << "\nF " << __FUNCTION__ << "(" << __FILE__ << ":" << __LINE__ << "): unexpected warnings\n"; \
    DUMP("warn"); \
    Passed = false; \
    return; \
  }

bool trace_doesnt_contain(string layer, string line) {
  return trace_count(layer, line) == 0;
}

bool trace_doesnt_contain(string expected) {
  vector<string> tmp = split(expected, ": ");
  return trace_doesnt_contain(tmp[0], tmp[1]);
}

bool trace_doesnt_contain(string layer, int frame, string line) {
  return trace_count(layer, frame, line) == 0;
}

#define CHECK_TRACE_DOESNT_CONTAIN(...)  CHECK(trace_doesnt_contain(__VA_ARGS__))



// manage layer counts in Trace_stream using RAII
struct lease_trace_frame {
  string layer;
  lease_trace_frame(string l) :layer(l) {
    if (!Trace_stream) return;
    Trace_stream->newline();
    ++Trace_stream->frame[layer];
  }
  ~lease_trace_frame() {
    if (!Trace_stream) return;
    Trace_stream->newline();
    --Trace_stream->frame[layer];
  }
};
#define new_trace_frame(layer)  lease_trace_frame leased_frame(layer);

bool check_trace_contents(string FUNCTION, string FILE, int LINE, string layer, int frame, string expected) {  // multiple layers, hierarchical layers
  vector<string> expected_lines = split(expected, "");  // hack: doesn't handle newlines in embedded in lines
  size_t curr_expected_line = 0;
  while (curr_expected_line < expected_lines.size() && expected_lines[curr_expected_line].empty())
    ++curr_expected_line;
  if (curr_expected_line == expected_lines.size()) return true;
  Trace_stream->newline();
  ostringstream output;
  vector<string> layers = split(layer, ",");
  for (vector<pair<string, pair<int, string> > >::iterator p = Trace_stream->past_lines.begin(); p != Trace_stream->past_lines.end(); ++p) {
    if (!layer.empty() && !any_prefix_match(layers, p->first))
      continue;
    if (p->second.first != frame)
      continue;
    if (p->second.second != expected_lines[curr_expected_line])
      continue;
    ++curr_expected_line;
    while (curr_expected_line < expected_lines.size() && expected_lines[curr_expected_line].empty())
      ++curr_expected_line;
    if (curr_expected_line == expected_lines.size()) return true;
  }

  ++Num_failures;
  cerr << "\nF " << FUNCTION << "(" << FILE << ":" << LINE << "): missing [" << expected_lines[curr_expected_line] << "] in trace/" << frame << ":\n";
  DUMP(layer);
  Passed = false;
  return false;
}

#define CHECK_TRACE_TOP(layer, expected)  CHECK_TRACE_CONTENTS(layer, 1, expected)



vector<string> split(string s, string delim) {
  vector<string> result;
  string::size_type begin=0, end=s.find(delim);
  while (true) {
    if (end == NOT_FOUND) {
      result.push_back(string(s, begin, NOT_FOUND));
      break;
    }
    result.push_back(string(s, begin, end-begin));
    begin = end+delim.size();
    end = s.find(delim, begin);
  }
  return result;
}

bool any_prefix_match(const vector<string>& pats, const string& needle) {
  if (pats.empty()) return false;
  if (*pats[0].rbegin() != '/')
    // prefix match not requested
    return find(pats.begin(), pats.end(), needle) != pats.end();
  // first pat ends in a '/'; assume all pats do.
  for (vector<string>::const_iterator p = pats.begin(); p != pats.end(); ++p)
    if (headmatch(needle, *p)) return true;
  return false;
}

bool prefix_match(const string& pat, const string& needle) {
  if (*pat.rbegin() != '/')
    // prefix match not requested
    return pat == needle;
  return headmatch(needle, pat);
}

bool headmatch(const string& s, const string& pat) {
  if (pat.size() > s.size()) return false;
  return std::mismatch(pat.begin(), pat.end(), s.begin()).first == pat.end();
}

:(before "End Includes")
#include<cstdlib>

#include<string>
using std::string;
#define NOT_FOUND string::npos

#include<vector>
using std::vector;
#include<list>
using std::list;
#include<utility>
using std::pair;

#include<tr1/unordered_map>
using std::tr1::unordered_map;
#include<tr1/unordered_set>
using std::tr1::unordered_set;
#include<algorithm>

#include<iostream>
using std::istream;
using std::ostream;
using std::iostream;
using std::cin;
using std::cout;
using std::cerr;

#include<sstream>
using std::stringstream;
using std::istringstream;
using std::ostringstream;

#include<fstream>
using std::ifstream;
using std::ofstream;

#define unused  __attribute__((unused))