// Reorder a file based on directives starting with ':(' (tangle directives).
// Insert #line directives to preserve line numbers in the original.
// Clear lines starting with '//:' (tangle comments).
//// Preliminaries regarding line number management
struct Line {
string filename;
size_t line_number;
string contents;
Line() :line_number(0) {}
Line(const string& text) :line_number(0) {
contents = text;
}
Line(const string& text, const string& f, const size_t& l) {
contents = text;
filename = f;
line_number = l;
}
Line(const string& text, const Line& origin) {
contents = text;
filename = origin.filename;
line_number = origin.line_number;
}
};
// Emit a list of line contents, inserting directives just at discontinuities.
// Needs to be a macro because 'out' can have the side effect of creating a
// new trace in Trace_stream.
#define EMIT(lines, out) if (!lines.empty()) { \
string last_file = lines.begin()->filename; \
size_t last_line = lines.begin()->line_number-1; \
out << line_directive(lines.begin()->line_number, lines.begin()->filename) << '\n'; \
for (list<Line>::const_iterator p = lines.begin(); p != lines.end(); ++p) { \
if (last_file != p->filename || last_line != p->line_number-1) \
out << line_directive(p->line_number, p->filename) << '\n'; \
out << p->contents << '\n'; \
last_file = p->filename; \
last_line = p->line_number; \
} \
}
string line_directive(size_t line_number, string filename) {
ostringstream result;
if (filename.empty())
result << "#line " << line_number;
else
result << "#line " << line_number << " \"" << filename << '"';
return result.str();
}
//// Tangle
string Toplevel = "run";
int tangle(int argc, const char* argv[]) {
list<Line> result;
for (int i = 1; i < argc; ++i) {
//? cerr << "new file " << argv[i] << '\n';
Toplevel = "run";
ifstream in(argv[i]);
tangle(in, argv[i], result);
}
EMIT(result, cout);
return 0;
}
void tangle(istream& in, const string& filename, list<Line>& out) {
string curr_line;
size_t line_number = 1;
while (!in.eof()) {
getline(in, curr_line);
if (starts_with(curr_line, ":(")) {
++line_number;
process_next_hunk(in, trim(curr_line), filename, line_number, out);
continue;
}
if (starts_with(curr_line, "//:")) {
++line_number;
continue;
}
out.push_back(Line(curr_line, filename, line_number));
++line_number;
}
// Trace all line contents, inserting directives just at discontinuities.
if (!Trace_stream) return;
EMIT(out, Trace_stream->stream("tangle"));
}
// just for tests
void tangle(istream& in, list<Line>& out) {
tangle(in, "", out);
}
void process_next_hunk(istream& in, const string& directive, const string& filename, size_t& line_number, list<Line>& out) {
istringstream directive_stream(directive.substr(2)); // length of ":("
string cmd = next_tangle_token(directive_stream);
// first slurp all lines until next directive
list<Line> hunk;
bool end_of_scenario_input = false;
{
string curr_line;
while (!in.eof()) {
std::streampos old = in.tellg();
getline(in, curr_line);
if (starts_with(curr_line, ":(")) {
in.seekg(old);
break;
}
if (starts_with(curr_line, "//:")) {
// tangle comments
++line_number;
continue;
}
if (cmd == "scenario") {
// ignore mu comments in scenarios, but only after the end of input
if (!starts_with(curr_line, "#") && !is_input(curr_line)) {
// remaining lines are checks
end_of_scenario_input = true;
}
else if (end_of_scenario_input && starts_with(curr_line, "#")) {
++line_number;
continue;
}
if (trim(curr_line).empty()) {
// ignore empty lines in scenarios, whether in input of after
++line_number;
continue;
}
}
hunk.push_back(Line(curr_line, filename, line_number));
++line_number;
}
}
if (cmd == "code") {
out.insert(out.end(), hunk.begin(), hunk.end());
return;
}
if (cmd == "scenarios") {
Toplevel = next_tangle_token(directive_stream);
return;
}
if (cmd == "scenario") {
list<Line> result;
string name = next_tangle_token(directive_stream);
emit_test(name, hunk, result);
//? cerr << out.size() << " " << result.size() << '\n';
out.insert(out.end(), result.begin(), result.end());
//? cerr << out.size() << " " << result.size() << '\n';
return;
}
if (cmd == "before" || cmd == "after" || cmd == "replace" || cmd == "replace{}" || cmd == "delete" || cmd == "delete{}") {
list<Line>::iterator target = locate_target(out, directive_stream);
if (target == out.end()) {
raise << "Couldn't find target " << directive << '\n' << die();
return;
}
indent_all(hunk, target);
if (cmd == "before") {
out.splice(target, hunk);
}
else if (cmd == "after") {
++target;
out.splice(target, hunk);
}
else if (cmd == "replace" || cmd == "delete") {
out.splice(target, hunk);
out.erase(target);
}
else if (cmd == "replace{}" || cmd == "delete{}") {
if (find_trim(hunk, ":OLD_CONTENTS") == hunk.end()) {
out.splice(target, hunk);
out.erase(target, balancing_curly(target));
}
else {
list<Line>::iterator next = balancing_curly(target);
list<Line> old_version;
old_version.splice(old_version.begin(), out, target, next);
old_version.pop_back(); old_version.pop_front(); // contents only please, not surrounding curlies
list<Line>::iterator new_pos = find_trim(hunk, ":OLD_CONTENTS");
indent_all(old_version, new_pos);
hunk.splice(new_pos, old_version);
hunk.erase(new_pos);
out.splice(next, hunk);
}
}
return;
}
raise << "unknown directive " << cmd << '\n' << die();
}
list<Line>::iterator locate_target(list<Line>& out, istream& directive_stream) {
string pat = next_tangle_token(directive_stream);
if (pat == "") return out.end();
string next_token = next_tangle_token(directive_stream);
if (next_token == "") {
return find_substr(out, pat);
}
// first way to do nested pattern: pattern 'following' intermediate
else if (next_token == "following") {
string pat2 = next_tangle_token(directive_stream);
if (pat2 == "") return out.end();
list<Line>::iterator intermediate = find_substr(out, pat2);
if (intermediate == out.end()) return out.end();
return find_substr(out, intermediate, pat);
}
// second way to do nested pattern: intermediate 'then' pattern
else if (next_token == "then") {
list<Line>::iterator intermediate = find_substr(out, pat);
if (intermediate == out.end()) return out.end();
string pat2 = next_tangle_token(directive_stream);
if (pat2 == "") return out.end();
return find_substr(out, intermediate, pat2);
}
raise << "unknown keyword in directive: " << next_token << '\n';
return out.end();
}
// indent all lines in l like indentation at exemplar
void indent_all(list<Line>& l, list<Line>::iterator exemplar) {
string curr_indent = indent(exemplar->contents);
for (list<Line>::iterator p = l.begin(); p != l.end(); ++p)
if (!p->contents.empty())
p->contents.insert(p->contents.begin(), curr_indent.begin(), curr_indent.end());
}
string next_tangle_token(istream& in) {
in >> std::noskipws;
ostringstream out;
skip_whitespace(in);
if (in.peek() == '"')
slurp_tangle_string(in, out);
else
slurp_word(in, out);
return out.str();
}
void slurp_tangle_string(istream& in, ostream& out) {
in.get();
char c;
while (in >> c) {
if (c == '\\') // only works for double-quotes
continue;
if (c == '"')
break;
out << c;
}
}
void slurp_word(istream& in, ostream& out) {
char c;
while (in >> c) {
if (isspace(c) || c == ')') {
in.putback(c);
break;
}
out << c;
}
}
void skip_whitespace(istream& in) {
while (isspace(in.peek()))
in.get();
}
list<Line>::iterator balancing_curly(list<Line>::iterator curr) {
long open_curlies = 0;
do {
for (string::iterator p = curr->contents.begin(); p != curr->contents.end(); ++p) {
if (*p == '{') ++open_curlies;
if (*p == '}') --open_curlies;
}
++curr;
// no guard so far against unbalanced curly, including inside comments or strings
} while (open_curlies != 0);
return curr;
}
// A scenario is one or more sessions separated by calls to CLEAR_TRACE ('===')
// A session is:
// one or more lines of escaped setup in C/C++ ('%')
// followed by one or more lines of input,
// followed optionally by (in order):
// one or more lines expected in trace in order ('+')
// one or more lines trace shouldn't include ('-')
// one or more lines expressing counts of specific layers emitted in trace ('$')
// a directive to print the trace just for debugging ('?')
// Remember to update is_input below if you add to this format.
void emit_test(const string& name, list<Line>& lines, list<Line>& result) {
result.push_back(Line("void test_"+name+"() {", front(lines).filename, front(lines).line_number-1)); // use line number of directive
while (!lines.empty()) {
while (!lines.empty() && starts_with(front(lines).contents, "% ")) {
result.push_back(Line(" "+front(lines).contents.substr(strlen("% ")), front(lines)));
lines.pop_front();
}
if (lines.empty()) break;
result.push_back(input_lines(lines));
if (!lines.empty() && !front(lines).contents.empty() && front(lines).contents.at(0) == '+')
result.push_back(expected_in_trace(lines));
while (!lines.empty() && !front(lines).contents.empty() && front(lines).contents.at(0) == '-') {
result.push_back(expected_not_in_trace(front(lines)));
lines.pop_front();
}
if (!lines.empty() && front(lines).contents.at(0) == '$') {
const string& in = front(lines).contents;
size_t pos = in.find(": ");
string layer = in.substr(1, pos-1);
string count = in.substr(pos+2);
result.push_back(Line(" CHECK_TRACE_COUNT(\""+layer+"\", "+count+");", front(lines)));
lines.pop_front();
}
if (!lines.empty() && front(lines).contents == "===") {
result.push_back(Line(" CLEAR_TRACE;", front(lines)));
lines.pop_front();
}
if (!lines.empty() && front(lines).contents == "?") {
result.push_back(Line(" DUMP(\"\");", front(lines)));
lines.pop_front();
}
}
result.push_back(Line("}"));
}
bool is_input(const string& line) {
if (line.empty()) return true;
return line != "===" && line.find_first_of("+-$?%") != 0;
}
Line input_lines(list<Line>& hunk) {
assert(!hunk.empty());
Line result;
result.line_number = hunk.front().line_number;
result.filename = hunk.front().filename;
while (!hunk.empty() && is_input(hunk.front().contents)) {
result.contents += hunk.front().contents+""; // temporary delimiter; replace with escaped newline after escaping other backslashes
hunk.pop_front();
}
result.contents = " "+Toplevel+"(\""+escape(result.contents)+"\");";
return result;
}
Line expected_in_trace(list<Line>& hunk) {
Line result;
result.line_number = hunk.front().line_number;
result.filename = hunk.front().filename;
while (!hunk.empty() && !front(hunk).contents.empty() && front(hunk).contents.at(0) == '+') {
hunk.front().contents.erase(0, 1);
result.contents += hunk.front().contents+"";
hunk.pop_front();
}
result.contents = " CHECK_TRACE_CONTENTS(\""+escape(result.contents)+"\");";
return result;
}
Line expected_not_in_trace(const Line& line) {
Line result;
result.line_number = line.line_number;
result.filename = line.filename;
result.contents = " CHECK_TRACE_DOESNT_CONTAIN(\""+escape(line.contents.substr(1))+"\");";
return result;
}
list<Line>::iterator find_substr(list<Line>& in, const string& pat) {
for (list<Line>::iterator p = in.begin(); p != in.end(); ++p)
if (p->contents.find(pat) != string::npos)
return p;
return in.end();
}
list<Line>::iterator find_substr(list<Line>& in, list<Line>::iterator p, const string& pat) {
for (; p != in.end(); ++p)
if (p->contents.find(pat) != string::npos)
return p;
return in.end();
}
list<Line>::iterator find_trim(list<Line>& in, const string& pat) {
for (list<Line>::iterator p = in.begin(); p != in.end(); ++p)
if (trim(p->contents) == pat)
return p;
return in.end();
}
string escape(string s) {
s = replace_all(s, "\\", "\\\\");
s = replace_all(s, "\"", "\\\"");
s = replace_all(s, "", "\\n");
return s;
}
string replace_all(string s, const string& a, const string& b) {
for (size_t pos = s.find(a); pos != string::npos; pos = s.find(a, pos+b.size()))
s = s.replace(pos, a.size(), b);
return s;
}
bool any_line_starts_with(const list<Line>& lines, const string& pat) {
for (list<Line>::const_iterator p = lines.begin(); p != lines.end(); ++p)
if (starts_with(p->contents, pat)) return true;
return false;
}
bool any_non_input_line(const list<Line>& lines) {
for (list<Line>::const_iterator p = lines.begin(); p != lines.end(); ++p)
if (!is_input(p->contents)) return true;
return false;
}
// does s start with pat, after skipping whitespace?
// pat can't start with whitespace
bool starts_with(const string& s, const string& pat) {
for (size_t pos = 0; pos < s.size(); ++pos)
if (!isspace(s.at(pos)))
return s.compare(pos, pat.size(), pat) == 0;
return false;
}
string indent(const string& s) {
for (size_t pos = 0; pos < s.size(); ++pos)
if (!isspace(s.at(pos)))
return s.substr(0, pos);
return "";
}
string strip_indent(const string& s, size_t n) {
if (s.empty()) return "";
string::const_iterator curr = s.begin();
while (curr != s.end() && n > 0 && isspace(*curr)) {
++curr;
--n;
}
return string(curr, s.end());
}
string trim(const string& s) {
string::const_iterator first = s.begin();
while (first != s.end() && isspace(*first))
++first;
if (first == s.end()) return "";
string::const_iterator last = --s.end();
while (last != s.begin() && isspace(*last))
--last;
++last;
return string(first, last);
}
const Line& front(const list<Line>& l) {
assert(!l.empty());
return l.front();
}