diff options
Diffstat (limited to 'tvix/eval/src')
| -rw-r--r-- | tvix/eval/src/errors.rs | 336 |
1 files changed, 94 insertions, 242 deletions
diff --git a/tvix/eval/src/errors.rs b/tvix/eval/src/errors.rs index ee55552c7ac5..9c3383fc5d94 100644 --- a/tvix/eval/src/errors.rs +++ b/tvix/eval/src/errors.rs @@ -35,96 +35,109 @@ use crate::{SourceCode, Value}; /// because Rust's magic `?`-syntax does not work on nested Result /// values like this. // TODO(amjoseph): investigate result<T,Either<CatchableErrorKind,ErrorKind>> -#[derive(Clone, Debug)] +#[derive(thiserror::Error, Clone, Debug)] pub enum CatchableErrorKind { + #[error("error thrown: {0}")] Throw(Box<str>), + + #[error("assertion failed")] AssertionFailed, + + #[error("feature {0} is not implemented yet")] UnimplementedFeature(Box<str>), + /// Resolving a user-supplied angle brackets path literal failed in some way. + #[error("Nix path entry could not be resolved: {0}")] NixPathResolution(Box<str>), } -impl Display for CatchableErrorKind { - fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result { - match self { - CatchableErrorKind::Throw(s) => write!(f, "error thrown: {}", s), - CatchableErrorKind::AssertionFailed => write!(f, "assertion failed"), - CatchableErrorKind::UnimplementedFeature(s) => { - write!(f, "feature {} is not implemented yet", s) - } - CatchableErrorKind::NixPathResolution(s) => { - write!(f, "Nix path entry could not be resolved: {}", s) - } - } - } -} - -#[derive(Clone, Debug)] +#[derive(thiserror::Error, Clone, Debug)] pub enum ErrorKind { /// These are user-generated errors through builtins. + #[error("evaluation aborted: {0}")] Abort(String), + #[error("division by zero")] DivisionByZero, - DuplicateAttrsKey { - key: String, - }, + #[error("attribute key '{key}' already defined")] + DuplicateAttrsKey { key: String }, /// Attempted to specify an invalid key type (e.g. integer) in a /// dynamic attribute name. + #[error( + "found attribute name '{0}' of type '{}', but attribute names must be strings", + .0.type_of() + )] InvalidAttributeName(Value), - AttributeNotFound { - name: String, - }, + #[error("attribute with name '{name}' could not be found in the set")] + AttributeNotFound { name: String }, /// Attempted to index into a list beyond its boundaries. - IndexOutOfBounds { - index: i64, - }, + #[error("list index '{index}' is out of bounds")] + IndexOutOfBounds { index: i64 }, /// Attempted to call `builtins.tail` on an empty list. + #[error("'tail' called on an empty list")] TailEmptyList, + #[error("expected value of type '{expected}', but found a '{actual}'")] TypeError { expected: &'static str, actual: &'static str, }, + #[error("can not compare a {lhs} with a {rhs}")] Incomparable { lhs: &'static str, rhs: &'static str, }, /// Resolving a user-supplied relative or home-relative path literal failed in some way. + #[error("could not resolve path: {0}")] RelativePathResolution(String), /// Dynamic keys are not allowed in some scopes. + #[error("dynamically evaluated keys are not allowed in {0}")] DynamicKeyInScope(&'static str), /// Unknown variable in statically known scope. + #[error("variable not found")] UnknownStaticVariable, /// Unknown variable in dynamic scope (with, rec, ...). + #[error( + r#"variable '{0}' could not be found + +Note that this occured within a `with`-expression. The problem may be related +to a missing value in the attribute set(s) included via `with`."# + )] UnknownDynamicVariable(String), /// User is defining the same variable twice at the same depth. + #[error("variable has already been defined")] VariableAlreadyDefined(Option<Span>), /// Attempt to call something that is not callable. + #[error("only functions and builtins can be called, but this is a '{0}'")] NotCallable(&'static str), /// Infinite recursion encountered while forcing thunks. + #[error("infinite recursion encountered")] InfiniteRecursion { first_force: Span, suspended_at: Option<Span>, content_span: Option<Span>, }, + // Errors themselves ignored here & handled in Self::spans instead + #[error("failed to parse Nix code:")] ParseErrors(Vec<rnix::parser::ParseError>), /// An error occured while executing some native code (e.g. a /// builtin), and needs to be chained up. + #[error("while evaluating this as native code ({gen_type})")] NativeError { gen_type: &'static str, err: Box<Error>, @@ -132,31 +145,44 @@ pub enum ErrorKind { /// An error occured while executing Tvix bytecode, but needs to /// be chained up. + #[error("while evaluating this Nix code")] BytecodeError(Box<Error>), /// Given type can't be coerced to a string in the respective context + #[error("cannot ({}) coerce {from} to a string{}", + (if .kind.strong { "strongly" } else { "weakly" }), + (if *.from == "set" { + ", missing a `__toString` or `outPath` attribute" + } else { + "" + }) + )] NotCoercibleToString { from: &'static str, kind: CoercionKind, }, /// The given string doesn't represent an absolute path + #[error("string '{}' does not represent an absolute path", .0.to_string_lossy())] NotAnAbsolutePath(PathBuf), /// An error occurred when parsing an integer + #[error("invalid integer: {0}")] ParseIntError(ParseIntError), // Errors specific to nested attribute sets and merges thereof. /// Nested attributes can not be merged with an inherited value. - UnmergeableInherit { - name: SmolStr, - }, + #[error("cannot merge a nested attribute set into the inherited entry '{name}'")] + UnmergeableInherit { name: SmolStr }, /// Nested attributes can not be merged with values that are not /// literal attribute sets. + #[error("nested attribute sets or keys can only be merged with literal attribute sets")] UnmergeableValue, + // Errors themselves ignored here & handled in Self::spans instead /// Parse errors occured while importing a file. + #[error("parse errors occured while importing '{}'", .path.to_string_lossy())] ImportParseError { path: PathBuf, file: Arc<File>, @@ -164,44 +190,70 @@ pub enum ErrorKind { }, /// Compilation errors occured while importing a file. - ImportCompilerError { - path: PathBuf, - errors: Vec<Error>, - }, + #[error("compiler errors occured while importing '{}'", .path.to_string_lossy())] + ImportCompilerError { path: PathBuf, errors: Vec<Error> }, /// I/O errors + #[error("I/O error: {}", + ({ + let mut msg = String::new(); + + if let Some(path) = .path { + msg.push_str(&format!("{}: ", path.display())); + } + + msg.push_str(&.error.to_string()); + + msg + }) + )] IO { path: Option<PathBuf>, error: Rc<io::Error>, }, /// Errors parsing JSON, or serializing as JSON. + #[error("Error converting JSON to a Nix value or back: {0}")] JsonError(String), /// Nix value that can not be serialised to JSON. + #[error("a {0} cannot be converted to JSON")] NotSerialisableToJson(&'static str), /// Errors converting TOML to a value + #[error("Error converting TOML to a Nix value: {0}")] FromTomlError(String), /// An unexpected argument was supplied to a builtin + #[error("Unexpected agrument `{0}` passed to builtin")] UnexpectedArgumentBuiltin(NixString), /// An unexpected argument was supplied to a function that takes formal parameters - UnexpectedArgumentFormals { - arg: NixString, - formals_span: Span, - }, + #[error("Unexpected argument `{arg}` supplied to function")] + UnexpectedArgumentFormals { arg: NixString, formals_span: Span }, /// Invalid UTF-8 was encoutered somewhere + #[error("Invalid UTF-8 in string")] Utf8, /// Variant for errors that bubble up to eval from other Tvix /// components. + #[error("{0}")] TvixError(Rc<dyn error::Error>), /// Variant for code paths that are known bugs in Tvix (usually /// issues with the compiler/VM interaction). + #[error("{}", + ({ + let mut disp = format!("Tvix bug: {}", .msg); + + if let Some(metadata) = .metadata { + disp.push_str(&format!("; metadata: {:?}", metadata)); + } + + disp + }) + )] TvixBug { msg: &'static str, metadata: Option<Rc<dyn Debug>>, @@ -210,15 +262,18 @@ pub enum ErrorKind { /// Tvix internal warning for features triggered by users that are /// not actually implemented yet, and without which eval can not /// proceed. + #[error("feature not yet implemented in Tvix: {0}")] NotImplemented(&'static str), /// Internal variant which should disappear during error construction. + #[error("internal ErrorKind::WithContext variant leaked")] WithContext { context: String, underlying: Box<ErrorKind>, }, /// Unexpected context string + #[error("unexpected context string")] UnexpectedContext, /// Top-level evaluation result was a catchable Nix error, and @@ -227,10 +282,12 @@ pub enum ErrorKind { /// This variant **must** only be used at the top-level of /// tvix-eval when returning a result to the user, never inside of /// eval code. + #[error("{0}")] CatchableError(CatchableErrorKind), /// Invalid hash type specified, must be one of "md5", "sha1", "sha256" /// or "sha512" + #[error("unknown hash type '{0}'")] UnknownHashType(String), } @@ -334,211 +391,6 @@ impl Error { } } -impl Display for ErrorKind { - fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result { - match &self { - ErrorKind::Abort(msg) => write!(f, "evaluation aborted: {}", msg), - - ErrorKind::DivisionByZero => write!(f, "division by zero"), - - ErrorKind::DuplicateAttrsKey { key } => { - write!(f, "attribute key '{}' already defined", key) - } - - ErrorKind::InvalidAttributeName(val) => write!( - f, - "found attribute name '{}' of type '{}', but attribute names must be strings", - val, - val.type_of() - ), - - ErrorKind::AttributeNotFound { name } => write!( - f, - "attribute with name '{}' could not be found in the set", - name - ), - - ErrorKind::IndexOutOfBounds { index } => { - write!(f, "list index '{}' is out of bounds", index) - } - - ErrorKind::TailEmptyList => write!(f, "'tail' called on an empty list"), - - ErrorKind::TypeError { expected, actual } => write!( - f, - "expected value of type '{}', but found a '{}'", - expected, actual - ), - - ErrorKind::Incomparable { lhs, rhs } => { - write!(f, "can not compare a {} with a {}", lhs, rhs) - } - - ErrorKind::RelativePathResolution(err) => { - write!(f, "could not resolve path: {}", err) - } - - ErrorKind::DynamicKeyInScope(scope) => { - write!(f, "dynamically evaluated keys are not allowed in {}", scope) - } - - ErrorKind::UnknownStaticVariable => write!(f, "variable not found"), - - ErrorKind::UnknownDynamicVariable(name) => write!( - f, - r#"variable '{}' could not be found - -Note that this occured within a `with`-expression. The problem may be related -to a missing value in the attribute set(s) included via `with`."#, - name - ), - - ErrorKind::VariableAlreadyDefined(_) => write!(f, "variable has already been defined"), - - ErrorKind::NotCallable(other_type) => { - write!( - f, - "only functions and builtins can be called, but this is a '{}'", - other_type - ) - } - - ErrorKind::InfiniteRecursion { .. } => write!(f, "infinite recursion encountered"), - - // Errors themselves ignored here & handled in Self::spans instead - ErrorKind::ParseErrors(_) => write!(f, "failed to parse Nix code:"), - - ErrorKind::NativeError { gen_type, .. } => { - write!(f, "while evaluating this as native code ({})", gen_type) - } - - ErrorKind::BytecodeError(_) => write!(f, "while evaluating this Nix code"), - - ErrorKind::NotCoercibleToString { kind, from } => { - let kindly = if kind.strong { "strongly" } else { "weakly" }; - - let hint = if *from == "set" { - ", missing a `__toString` or `outPath` attribute" - } else { - "" - }; - - write!(f, "cannot ({kindly}) coerce {from} to a string{hint}") - } - - ErrorKind::NotAnAbsolutePath(given) => { - write!( - f, - "string '{}' does not represent an absolute path", - given.to_string_lossy() - ) - } - - ErrorKind::ParseIntError(err) => { - write!(f, "invalid integer: {}", err) - } - - ErrorKind::UnmergeableInherit { name } => { - write!( - f, - "cannot merge a nested attribute set into the inherited entry '{}'", - name - ) - } - - ErrorKind::UnmergeableValue => { - write!( - f, - "nested attribute sets or keys can only be merged with literal attribute sets" - ) - } - - // Errors themselves ignored here & handled in Self::spans instead - ErrorKind::ImportParseError { path, .. } => { - write!( - f, - "parse errors occured while importing '{}'", - path.to_string_lossy() - ) - } - - ErrorKind::ImportCompilerError { path, .. } => { - writeln!( - f, - "compiler errors occured while importing '{}'", - path.to_string_lossy() - ) - } - - ErrorKind::IO { path, error } => { - write!(f, "I/O error: ")?; - if let Some(path) = path { - write!(f, "{}: ", path.display())?; - } - write!(f, "{error}") - } - - ErrorKind::JsonError(msg) => { - write!(f, "Error converting JSON to a Nix value or back: {msg}") - } - - ErrorKind::NotSerialisableToJson(_type) => { - write!(f, "a {} cannot be converted to JSON", _type) - } - - ErrorKind::FromTomlError(msg) => { - write!(f, "Error converting TOML to a Nix value: {msg}") - } - - ErrorKind::UnexpectedArgumentBuiltin(arg) => { - write!(f, "Unexpected agrument `{arg}` passed to builtin",) - } - - ErrorKind::UnexpectedArgumentFormals { arg, .. } => { - write!(f, "Unexpected argument `{arg}` supplied to function",) - } - - ErrorKind::Utf8 => { - write!(f, "Invalid UTF-8 in string") - } - - ErrorKind::TvixError(inner_error) => { - write!(f, "{inner_error}") - } - - ErrorKind::TvixBug { msg, metadata } => { - write!(f, "Tvix bug: {}", msg)?; - - if let Some(metadata) = metadata { - write!(f, "; metadata: {:?}", metadata)?; - } - - Ok(()) - } - - ErrorKind::NotImplemented(feature) => { - write!(f, "feature not yet implemented in Tvix: {}", feature) - } - - ErrorKind::WithContext { .. } => { - panic!("internal ErrorKind::WithContext variant leaked") - } - - ErrorKind::UnexpectedContext => { - write!(f, "unexpected context string") - } - - ErrorKind::CatchableError(inner) => { - write!(f, "{}", inner) - } - - ErrorKind::UnknownHashType(hash_type) => { - write!(f, "unknown hash type '{}'", hash_type) - } - } - } -} - impl Display for Error { fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result { write!(f, "{}", self.kind) |