diff options
Diffstat (limited to 'src/libexpr/print.cc')
| -rw-r--r-- | src/libexpr/print.cc | 412 |
1 files changed, 410 insertions, 2 deletions
diff --git a/src/libexpr/print.cc b/src/libexpr/print.cc index 53ba70bdd..0e8f80888 100644 --- a/src/libexpr/print.cc +++ b/src/libexpr/print.cc @@ -1,25 +1,65 @@ -#include "print.hh" +#include <limits> #include <unordered_set> +#include "print.hh" +#include "ansicolor.hh" +#include "store-api.hh" +#include "english.hh" + namespace nix { +void printElided( + std::ostream & output, + unsigned int value, + const std::string_view single, + const std::string_view plural, + bool ansiColors) +{ + if (ansiColors) + output << ANSI_FAINT; + output << " «"; + pluralize(output, value, single, plural); + output << " elided»"; + if (ansiColors) + output << ANSI_NORMAL; +} + + std::ostream & -printLiteralString(std::ostream & str, const std::string_view string) +printLiteralString(std::ostream & str, const std::string_view string, size_t maxLength, bool ansiColors) { + size_t charsPrinted = 0; + if (ansiColors) + str << ANSI_MAGENTA; str << "\""; for (auto i = string.begin(); i != string.end(); ++i) { + if (charsPrinted >= maxLength) { + str << "\""; + printElided(str, string.length() - charsPrinted, "byte", "bytes", ansiColors); + return str; + } + if (*i == '\"' || *i == '\\') str << "\\" << *i; else if (*i == '\n') str << "\\n"; else if (*i == '\r') str << "\\r"; else if (*i == '\t') str << "\\t"; else if (*i == '$' && *(i+1) == '{') str << "\\" << *i; else str << *i; + charsPrinted++; } str << "\""; + if (ansiColors) + str << ANSI_NORMAL; return str; } std::ostream & +printLiteralString(std::ostream & str, const std::string_view string) +{ + return printLiteralString(str, string, std::numeric_limits<size_t>::max(), false); +} + +std::ostream & printLiteralBool(std::ostream & str, bool boolean) { str << (boolean ? "true" : "false"); @@ -90,5 +130,373 @@ printAttributeName(std::ostream & str, std::string_view name) { return str; } +bool isImportantAttrName(const std::string& attrName) +{ + return attrName == "type" || attrName == "_type"; +} + +typedef std::pair<std::string, Value *> AttrPair; + +struct ImportantFirstAttrNameCmp +{ + + bool operator()(const AttrPair& lhs, const AttrPair& rhs) const + { + auto lhsIsImportant = isImportantAttrName(lhs.first); + auto rhsIsImportant = isImportantAttrName(rhs.first); + return std::forward_as_tuple(!lhsIsImportant, lhs.first) + < std::forward_as_tuple(!rhsIsImportant, rhs.first); + } +}; + +typedef std::set<Value *> ValuesSeen; + +class Printer +{ +private: + std::ostream & output; + EvalState & state; + PrintOptions options; + std::optional<ValuesSeen> seen; + + void printRepeated() + { + if (options.ansiColors) + output << ANSI_MAGENTA; + output << "«repeated»"; + if (options.ansiColors) + output << ANSI_NORMAL; + } + + void printNullptr() + { + if (options.ansiColors) + output << ANSI_MAGENTA; + output << "«nullptr»"; + if (options.ansiColors) + output << ANSI_NORMAL; + } + + void printElided(unsigned int value, const std::string_view single, const std::string_view plural) + { + ::nix::printElided(output, value, single, plural, options.ansiColors); + } + + void printInt(Value & v) + { + if (options.ansiColors) + output << ANSI_CYAN; + output << v.integer; + if (options.ansiColors) + output << ANSI_NORMAL; + } + + void printFloat(Value & v) + { + if (options.ansiColors) + output << ANSI_CYAN; + output << v.fpoint; + if (options.ansiColors) + output << ANSI_NORMAL; + } + + void printBool(Value & v) + { + if (options.ansiColors) + output << ANSI_CYAN; + printLiteralBool(output, v.boolean); + if (options.ansiColors) + output << ANSI_NORMAL; + } + + void printString(Value & v) + { + printLiteralString(output, v.string.s, options.maxStringLength, options.ansiColors); + } + + void printPath(Value & v) + { + if (options.ansiColors) + output << ANSI_GREEN; + output << v.path().to_string(); // !!! escaping? + if (options.ansiColors) + output << ANSI_NORMAL; + } + + void printNull() + { + if (options.ansiColors) + output << ANSI_CYAN; + output << "null"; + if (options.ansiColors) + output << ANSI_NORMAL; + } + + void printDerivation(Value & v) + { + try { + Bindings::iterator i = v.attrs->find(state.sDrvPath); + NixStringContext context; + std::string storePath; + if (i != v.attrs->end()) + storePath = state.store->printStorePath(state.coerceToStorePath(i->pos, *i->value, context, "while evaluating the drvPath of a derivation")); + + if (options.ansiColors) + output << ANSI_GREEN; + output << "«derivation"; + if (!storePath.empty()) { + output << " " << storePath; + } + output << "»"; + if (options.ansiColors) + output << ANSI_NORMAL; + } catch (BaseError & e) { + printError_(e); + } + } + + void printAttrs(Value & v, size_t depth) + { + if (seen && !seen->insert(&v).second) { + printRepeated(); + return; + } + + if (options.force && options.derivationPaths && state.isDerivation(v)) { + printDerivation(v); + } else if (depth < options.maxDepth) { + output << "{ "; + + std::vector<std::pair<std::string, Value *>> sorted; + for (auto & i : *v.attrs) + sorted.emplace_back(std::pair(state.symbols[i.name], i.value)); + + if (options.maxAttrs == std::numeric_limits<size_t>::max()) + std::sort(sorted.begin(), sorted.end()); + else + std::sort(sorted.begin(), sorted.end(), ImportantFirstAttrNameCmp()); + + size_t attrsPrinted = 0; + for (auto & i : sorted) { + if (attrsPrinted >= options.maxAttrs) { + printElided(sorted.size() - attrsPrinted, "attribute", "attributes"); + break; + } + + printAttributeName(output, i.first); + output << " = "; + print(*i.second, depth + 1); + output << "; "; + attrsPrinted++; + } + + output << "}"; + } else + output << "{ ... }"; + } + + void printList(Value & v, size_t depth) + { + if (seen && v.listSize() && !seen->insert(&v).second) { + printRepeated(); + return; + } + + output << "[ "; + if (depth < options.maxDepth) { + size_t listItemsPrinted = 0; + for (auto elem : v.listItems()) { + if (listItemsPrinted >= options.maxListItems) { + printElided(v.listSize() - listItemsPrinted, "item", "items"); + break; + } + + if (elem) { + print(*elem, depth + 1); + } else { + printNullptr(); + } + output << " "; + listItemsPrinted++; + } + } + else + output << "... "; + output << "]"; + } + + void printFunction(Value & v) + { + if (options.ansiColors) + output << ANSI_BLUE; + output << "«"; + + if (v.isLambda()) { + output << "lambda"; + if (v.lambda.fun) { + if (v.lambda.fun->name) { + output << " " << state.symbols[v.lambda.fun->name]; + } + + std::ostringstream s; + s << state.positions[v.lambda.fun->pos]; + output << " @ " << filterANSIEscapes(s.str()); + } + } else if (v.isPrimOp()) { + if (v.primOp) + output << *v.primOp; + else + output << "primop"; + } else if (v.isPrimOpApp()) { + output << "partially applied "; + auto primOp = v.primOpAppPrimOp(); + if (primOp) + output << *primOp; + else + output << "primop"; + } else { + abort(); + } + + output << "»"; + if (options.ansiColors) + output << ANSI_NORMAL; + } + + void printThunk(Value & v) + { + if (v.isBlackhole()) { + // Although we know for sure that it's going to be an infinite recursion + // when this value is accessed _in the current context_, it's likely + // that the user will misinterpret a simpler «infinite recursion» output + // as a definitive statement about the value, while in fact it may be + // a valid value after `builtins.trace` and perhaps some other steps + // have completed. + if (options.ansiColors) + output << ANSI_RED; + output << "«potential infinite recursion»"; + if (options.ansiColors) + output << ANSI_NORMAL; + } else if (v.isThunk() || v.isApp()) { + if (options.ansiColors) + output << ANSI_MAGENTA; + output << "«thunk»"; + if (options.ansiColors) + output << ANSI_NORMAL; + } else { + abort(); + } + } + + void printExternal(Value & v) + { + v.external->print(output); + } + + void printUnknown() + { + if (options.ansiColors) + output << ANSI_RED; + output << "«unknown»"; + if (options.ansiColors) + output << ANSI_NORMAL; + } + + void printError_(BaseError & e) + { + if (options.ansiColors) + output << ANSI_RED; + output << "«" << e.msg() << "»"; + if (options.ansiColors) + output << ANSI_NORMAL; + } + + void print(Value & v, size_t depth) + { + output.flush(); + checkInterrupt(); + + if (options.force) { + try { + state.forceValue(v, v.determinePos(noPos)); + } catch (BaseError & e) { + printError_(e); + return; + } + } + + switch (v.type()) { + + case nInt: + printInt(v); + break; + + case nFloat: + printFloat(v); + break; + + case nBool: + printBool(v); + break; + + case nString: + printString(v); + break; + + case nPath: + printPath(v); + break; + + case nNull: + printNull(); + break; + + case nAttrs: + printAttrs(v, depth); + break; + + case nList: + printList(v, depth); + break; + + case nFunction: + printFunction(v); + break; + + case nThunk: + printThunk(v); + break; + + case nExternal: + printExternal(v); + break; + + default: + printUnknown(); + break; + } + } + +public: + Printer(std::ostream & output, EvalState & state, PrintOptions options) + : output(output), state(state), options(options) { } + + void print(Value & v) + { + if (options.trackRepeated) { + seen.emplace(); + } else { + seen.reset(); + } + + ValuesSeen seen; + print(v, 0); + } +}; + +void printValue(EvalState & state, std::ostream & output, Value & v, PrintOptions options) +{ + Printer(output, state, options).print(v); +} } |