DebugStackTracker class in one place

src/libcmd/command.cc

@@ -75,6 +75,8 @@ ref<EvalState> EvalCommand::getEvalState()
 
  printStaticEnvBindings(expr);
 
+ std::cout << evalState->vCallFlake << std::endl;
+
  std::cout << "expr: " << std::endl;
  expr.show(std::cout);
  std::cout << std::endl;

src/libcmd/repl.cc

@@ -451,6 +451,7 @@ bool NixRepl::processLine(string line)
  }
  else if (arg == "error") {
  if (this->debugError.has_value()) {
+ // TODO user --show-trace setting?
  showErrorInfo(std::cout, (*debugError)->info(), true);
  }
  else

src/libexpr/eval.cc

@@ -17,6 +17,7 @@
 #include <sys/resource.h>
 #include <iostream>
 #include <fstream>
+#include <functional>
 
 #include <sys/resource.h>
 
@@ -854,13 +855,20 @@ LocalNoInlineNoReturn(void throwAssertionError(const Pos & pos, const char * s,
 
 LocalNoInlineNoReturn(void throwUndefinedVarError(const Pos & pos, const char * s, const string & s1, Env & env, Expr *expr))
 {
+ std::cout << "throwUndefinedVarError" << std::endl;
+
+ std::cout << "loggerSettings.showTrace: " << loggerSettings.showTrace << std::endl;
+
  auto error = UndefinedVarError({
  .msg = hintfmt(s, s1),
  .errPos = pos
  });
 
- if (debuggerHook && expr)
+ if (debuggerHook && expr) {
+
+ std::cout << "throwUndefinedVarError debuggerHook" << std::endl;
  debuggerHook(error, env, *expr);
+ }
 
  throw error;
 }
@@ -888,6 +896,16 @@ LocalNoInline(void addErrorTrace(Error & e, const Pos & pos, const char * s, con
  e.addTrace(pos, s, s2);
 }
 
+// LocalNoInline(void makeErrorTrace(Error & e, const char * s, const string & s2))
+// {
+// Trace { .pos = e, .hint = hint }
+// }
+
+// LocalNoInline(void makeErrorTrace(Error & e, const Pos & pos, const char * s, const string & s2))
+// {
+// return Trace { .pos = e, .hint = hintfmt(s, s2); };
+// }
+
 void mkString(Value & v, const char * s)
 {
  v.mkString(dupString(s));
@@ -934,7 +952,7 @@ inline Value * EvalState::lookupVar(Env * env, const ExprVar & var, bool noEval)
  return j->value;
  }
  if (!env->prevWith) {
- throwUndefinedVarError(var.pos, "undefined variable '%1%'", var.name, *env, 0);
+ throwUndefinedVarError(var.pos, "undefined variable '%1%'", var.name, *env, (Expr*)&var);
  }
  for (size_t l = env->prevWith; l; --l, env = env->up) ;
  }
@@ -1092,6 +1110,39 @@ void EvalState::resetFileCache()
  fileParseCache.clear();
 }
 
+class DebugTraceStacker {
+ public:
+ DebugTraceStacker(EvalState &evalState, Trace t)
+ :evalState(evalState), trace(t)
+ {
+ evalState.debugTraces.push_front(t);
+ }
+ ~DebugTraceStacker() {
+ // assert(evalState.debugTraces.front() == trace);
+ evalState.debugTraces.pop_front();
+ }
+
+ EvalState &evalState;
+ Trace trace;
+
+};
+
+// class DebugTraceStacker {
+// DebugTraceStacker(std::ref<EvalState> evalState, std::ref<Trace> t)
+// :evalState(evalState), trace(t)
+// {
+// evalState->debugTraces.push_front(t);
+// }
+// ~DebugTraceStacker() {
+// assert(evalState->debugTraces.pop_front() == trace);
+// }
+
+// std::ref<EvalState> evalState;
+// std::ref<Trace> trace;
+
+// };
+
+
 
 void EvalState::cacheFile(
  const Path & path,
@@ -1103,6 +1154,15 @@ void EvalState::cacheFile(
  fileParseCache[resolvedPath] = e;
 
  try {
+ std::unique_ptr<DebugTraceStacker> dts = debuggerHook ? 
+ std::unique_ptr<DebugTraceStacker>(new DebugTraceStacker(*this, 
+ Trace { .pos = (e->getPos() ? std::optional(ErrPos(*e->getPos())) : std::nullopt), 
+ .hint = hintfmt("while evaluating the file '%1%':", resolvedPath)
+ }
+ )) : std::unique_ptr<DebugTraceStacker>();
+
+ // Trace( .pos = (e->getPos() ? std::optional(ErrPos(*e->getPos())): 
+ // std::nullopt), hintfmt("while evaluating the file '%1%':", resolvedPath)); 
  // Enforce that 'flake.nix' is a direct attrset, not a
  // computation.
  if (mustBeTrivial &&
@@ -1472,6 +1532,7 @@ void EvalState::callFunction(Value & fun, size_t nrArgs, Value * * args, Value &
  try {
  lambda.body->eval(*this, env2, vCur);
  } catch (Error & e) {
+ std::cout << "eval showErrorInfo showTrace: " << loggerSettings.showTrace.get() << std::endl;
  if (loggerSettings.showTrace.get()) {
  addErrorTrace(e, lambda.pos, "while evaluating %s",
  (lambda.name.set()

src/libexpr/eval.hh

@@ -109,6 +109,8 @@ public:
  RootValue vCallFlake = nullptr;
  RootValue vImportedDrvToDerivation = nullptr;
 
+ std::list<Trace> debugTraces;
+
 private:
  SrcToStore srcToStore;
 

src/libexpr/nixexpr.hh

@@ -84,6 +84,7 @@ struct Expr
  virtual void setName(Symbol & name);
 
  std::shared_ptr<const StaticEnv> staticenv;
+ virtual Pos* getPos() = 0;
 };
 
 std::ostream & operator << (std::ostream & str, const Expr & e);
@@ -100,6 +101,8 @@ struct ExprInt : Expr
  ExprInt(NixInt n) : n(n) { mkInt(v, n); };
  COMMON_METHODS
  Value * maybeThunk(EvalState & state, Env & env);
+
+ Pos* getPos() { return 0; }
 };
 
 struct ExprFloat : Expr
@@ -109,6 +112,8 @@ struct ExprFloat : Expr
  ExprFloat(NixFloat nf) : nf(nf) { mkFloat(v, nf); };
  COMMON_METHODS
  Value * maybeThunk(EvalState & state, Env & env);
+
+ Pos* getPos() { return 0; }
 };
 
 struct ExprString : Expr
@@ -118,13 +123,17 @@ struct ExprString : Expr
  ExprString(const Symbol & s) : s(s) { mkString(v, s); };
  COMMON_METHODS
  Value * maybeThunk(EvalState & state, Env & env);
+
+ Pos* getPos() { return 0; }
 };
 
 /* Temporary class used during parsing of indented strings. */
 struct ExprIndStr : Expr
 {
  string s;
  ExprIndStr(const string & s) : s(s) { };
+
+ Pos* getPos() { return 0; }
 };
 
 struct ExprPath : Expr
@@ -134,6 +143,7 @@ struct ExprPath : Expr
  ExprPath(const string & s) : s(s) { v.mkPath(this->s.c_str()); };
  COMMON_METHODS
  Value * maybeThunk(EvalState & state, Env & env);
+ Pos* getPos() { return 0; }
 };
 
 typedef uint32_t Level;
@@ -161,6 +171,7 @@ struct ExprVar : Expr
  ExprVar(const Pos & pos, const Symbol & name) : pos(pos), name(name) { };
  COMMON_METHODS
  Value * maybeThunk(EvalState & state, Env & env);
+ Pos* getPos() { return &pos; }
 };
 
 struct ExprSelect : Expr
@@ -171,6 +182,7 @@ struct ExprSelect : Expr
  ExprSelect(const Pos & pos, Expr * e, const AttrPath & attrPath, Expr * def) : pos(pos), e(e), def(def), attrPath(attrPath) { };
  ExprSelect(const Pos & pos, Expr * e, const Symbol & name) : pos(pos), e(e), def(0) { attrPath.push_back(AttrName(name)); };
  COMMON_METHODS
+ Pos* getPos() { return &pos; }
 };
 
 struct ExprOpHasAttr : Expr
@@ -179,6 +191,7 @@ struct ExprOpHasAttr : Expr
  AttrPath attrPath;
  ExprOpHasAttr(Expr * e, const AttrPath & attrPath) : e(e), attrPath(attrPath) { };
  COMMON_METHODS
+ Pos* getPos() { return e->getPos(); }
 };
 
 struct ExprAttrs : Expr
@@ -207,13 +220,15 @@ struct ExprAttrs : Expr
  ExprAttrs(const Pos &pos) : recursive(false), pos(pos) { };
  ExprAttrs() : recursive(false), pos(noPos) { };
  COMMON_METHODS
+ Pos* getPos() { return &pos; }
 };
 
 struct ExprList : Expr
 {
  std::vector<Expr *> elems;
  ExprList() { };
  COMMON_METHODS
+ Pos* getPos() { return 0; }
 };
 
 struct Formal
@@ -252,6 +267,7 @@ struct ExprLambda : Expr
  string showNamePos() const;
  inline bool hasFormals() const { return formals != nullptr; }
  COMMON_METHODS
+ Pos* getPos() { return &pos; }
 };
 
 struct ExprCall : Expr
@@ -263,6 +279,7 @@ struct ExprCall : Expr
  : fun(fun), args(args), pos(pos)
  { }
  COMMON_METHODS
+ Pos* getPos() { return &pos; }
 };
 
 struct ExprLet : Expr
@@ -271,6 +288,7 @@ struct ExprLet : Expr
  Expr * body;
  ExprLet(ExprAttrs * attrs, Expr * body) : attrs(attrs), body(body) { };
  COMMON_METHODS
+ Pos* getPos() { return 0; }
 };
 
 struct ExprWith : Expr
@@ -280,6 +298,7 @@ struct ExprWith : Expr
  size_t prevWith;
  ExprWith(const Pos & pos, Expr * attrs, Expr * body) : pos(pos), attrs(attrs), body(body) { };
  COMMON_METHODS
+ Pos* getPos() { return &pos; }
 };
 
 struct ExprIf : Expr
@@ -288,6 +307,7 @@ struct ExprIf : Expr
  Expr * cond, * then, * else_;
  ExprIf(const Pos & pos, Expr * cond, Expr * then, Expr * else_) : pos(pos), cond(cond), then(then), else_(else_) { };
  COMMON_METHODS
+ Pos* getPos() { return &pos; }
 };
 
 struct ExprAssert : Expr
@@ -296,13 +316,15 @@ struct ExprAssert : Expr
  Expr * cond, * body;
  ExprAssert(const Pos & pos, Expr * cond, Expr * body) : pos(pos), cond(cond), body(body) { };
  COMMON_METHODS
+ Pos* getPos() { return &pos; }
 };
 
 struct ExprOpNot : Expr
 {
  Expr * e;
  ExprOpNot(Expr * e) : e(e) { };
  COMMON_METHODS
+ Pos* getPos() { return 0; }
 };
 
 #define MakeBinOp(name, s) \
@@ -321,6 +343,7 @@ struct ExprOpNot : Expr
  e1->bindVars(env); e2->bindVars(env); \
  } \
  void eval(EvalState & state, Env & env, Value & v); \
+ Pos* getPos() { return &pos; } \
  };
 
 MakeBinOp(ExprOpEq, "==")
@@ -339,13 +362,15 @@ struct ExprConcatStrings : Expr
  ExprConcatStrings(const Pos & pos, bool forceString, vector<Expr *> * es)
  : pos(pos), forceString(forceString), es(es) { };
  COMMON_METHODS
+ Pos* getPos() { return &pos; }
 };
 
 struct ExprPos : Expr
 {
  Pos pos;
  ExprPos(const Pos & pos) : pos(pos) { };
  COMMON_METHODS
+ Pos* getPos() { return &pos; }
 };
 
 

src/libutil/error.cc

@@ -221,6 +221,8 @@ static std::string indent(std::string_view indentFirst, std::string_view indentR
 
 std::ostream & showErrorInfo(std::ostream & out, const ErrorInfo & einfo, bool showTrace)
 {
+ std::cout << "showErrorInfo showTrace: " << showTrace << std::endl;
+
  std::string prefix;
  switch (einfo.level) {
  case Verbosity::lvlError: {

src/libutil/logging.hh

@@ -38,6 +38,7 @@ typedef uint64_t ActivityId;
 struct LoggerSettings : Config
 {
  Setting<bool> showTrace{
+ // this, false, "show-trace",
  this, false, "show-trace",
  R"(
  Where Nix should print out a stack trace in case of Nix