eval: Fix crash on missing printValue tBlackhole case

Fixes #8119
This commit is contained in:
Robert Hensing 2023-04-01 22:05:06 +02:00
parent 10dc2e2e7c
commit 1c55544a42
2 changed files with 17 additions and 0 deletions

View file

@ -173,7 +173,17 @@ void Value::print(const SymbolTable & symbols, std::ostream & str,
case tFloat:
str << fpoint;
break;
case tBlackhole:
// 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.
str << "«potential infinite recursion»";
break;
default:
printError("Nix evaluator internal error: Value::print(): invalid value type %1%", internalType);
abort();
}
}

View file

@ -5,12 +5,19 @@ export NIX_REMOTE=dummy://
export NIX_STORE_DIR=/nix/store
nix-instantiate --eval -E 'builtins.trace "Hello" 123' 2>&1 | grepQuiet Hello
nix-instantiate --eval -E 'builtins.trace "Hello" 123' 2>/dev/null | grepQuiet 123
nix-instantiate --eval -E 'builtins.addErrorContext "Hello" 123' 2>&1
nix-instantiate --trace-verbose --eval -E 'builtins.traceVerbose "Hello" 123' 2>&1 | grepQuiet Hello
nix-instantiate --eval -E 'builtins.traceVerbose "Hello" 123' 2>&1 | grepQuietInverse Hello
nix-instantiate --show-trace --eval -E 'builtins.addErrorContext "Hello" 123' 2>&1 | grepQuietInverse Hello
expectStderr 1 nix-instantiate --show-trace --eval -E 'builtins.addErrorContext "Hello" (throw "Foo")' | grepQuiet Hello
nix-instantiate --eval -E 'let x = builtins.trace { x = x; } true; in x' \
2>&1 | grepQuiet -E 'trace: { x = «potential infinite recursion»; }'
nix-instantiate --eval -E 'let x = { repeating = x; tracing = builtins.trace x true; }; in x.tracing'\
2>&1 | grepQuiet -F 'trace: { repeating = «repeated»; tracing = «potential infinite recursion»; }'
set +x
fail=0