Merge pull request #212 from aiken-lang/better-type-check-errors

Better type check errors

Cargo.lock

@@ -80,6 +80,7 @@ dependencies = [
  "itertools",
  "miette",
  "ordinal",
+ "owo-colors",
  "pretty_assertions",
  "strum",
  "thiserror",

crates/aiken-lang/Cargo.toml

@@ -13,9 +13,11 @@ authors = ["Lucas Rosa <x@rvcas.dev>", "Kasey White <kwhitemsg@gmail.com>"]
 [dependencies]
 chumsky = "0.8.0"
 indexmap = "1.9.1"
+indoc = "1.0.7"
 itertools = "0.10.5"
 miette = "5.2.0"
 ordinal = "0.3.2"
+owo-colors = "3.5.0"
 strum = "0.24.1"
 thiserror = "1.0.37"
 uplc = { path = '../uplc', version = "0.0.25" }

crates/aiken-lang/src/format.rs

@@ -488,7 +488,7 @@ impl<'comments> Formatter<'comments> {
         .group()
     }
 
-    fn type_arguments<'a>(&mut self, args: &'a [Annotation]) -> Document<'a> {
+    pub fn type_arguments<'a>(&mut self, args: &'a [Annotation]) -> Document<'a> {
         wrap_generics(args.iter().map(|t| self.annotation(t)))
     }
 
@@ -796,7 +796,7 @@ impl<'comments> Formatter<'comments> {
         }
     }
 
-    fn pattern_constructor<'a>(
+    pub fn pattern_constructor<'a>(
         &mut self,
         name: &'a str,
         args: &'a [CallArg<UntypedPattern>],
@@ -1478,7 +1478,7 @@ impl<'comments> Formatter<'comments> {
         list(elements_document, elements.len(), tail)
     }
 
-    fn pattern<'a>(&mut self, pattern: &'a UntypedPattern) -> Document<'a> {
+    pub fn pattern<'a>(&mut self, pattern: &'a UntypedPattern) -> Document<'a> {
         let comments = self.pop_comments(pattern.location().start);
         let doc = match pattern {
             Pattern::Int { value, .. } => value.to_doc(),

crates/aiken-lang/src/levenshtein.rs

@@ -0,0 +1,42 @@
+use std::cmp;
+
+/// Calculate Levenshtein distance for two UTF-8 encoded strings.
+///
+/// Returns a minimum number of edits to transform from source to target string.
+///
+/// Levenshtein distance accepts three edit operations: insertion, deletion,
+/// and substitution.
+///
+/// References:
+///
+/// - [Levenshtein distance in Cargo][1]
+/// - [Ilia Schelokov: Optimizing loop heavy Rust code][2]
+///
+/// [1]: https://github.com/rust-lang/cargo/blob/7d7fe6797ad07f313706380d251796702272b150/src/cargo/util/lev_distance.rs
+/// [2]: https://thaumant.me/optimizing-loop-heavy-rust/
+pub fn distance(source: &str, target: &str) -> usize {
+    if source.is_empty() {
+        return target.len();
+    }
+    if target.is_empty() {
+        return source.len();
+    }
+
+    let mut distances = (0..=target.chars().count()).collect::<Vec<_>>();
+
+    for (i, ch1) in source.chars().enumerate() {
+        let mut sub = i;
+        distances[0] = sub + 1;
+        for (j, ch2) in target.chars().enumerate() {
+            let dist = cmp::min(
+                cmp::min(distances[j], distances[j + 1]) + 1,
+                sub + (ch1 != ch2) as usize,
+            );
+
+            sub = distances[j + 1];
+            distances[j + 1] = dist;
+        }
+    }
+
+    *distances.last().unwrap()
+}

crates/aiken-lang/src/lib.rs

@@ -9,6 +9,7 @@ pub mod builder;
 pub mod builtins;
 pub mod expr;
 pub mod format;
+pub mod levenshtein;
 pub mod parser;
 pub mod pretty;
 pub mod tipo;

crates/aiken-lang/src/parser/error.rs

@@ -80,21 +80,12 @@ impl<T: Into<Pattern>> chumsky::Error<T> for ParseError {
 
 #[derive(Debug, PartialEq, Eq, Diagnostic, thiserror::Error)]
 pub enum ErrorKind {
-    #[error("Unexpected end")]
+    #[error("I arrived at the end of the file unexpectedly.")]
     UnexpectedEnd,
     #[error("{0}")]
     #[diagnostic(help("{}", .0.help().unwrap_or_else(|| Box::new(""))))]
     Unexpected(Pattern),
-    #[error("Unclosed {start}")]
+    #[error("I discovered an invalid tuple index.")]
-    Unclosed {
-        start: Pattern,
-        #[label]
-        before_span: Span,
-        before: Option<Pattern>,
-    },
-    #[error("No end branch")]
-    NoEndBranch,
-    #[error("Invalid tuple index")]
     #[diagnostic()]
     InvalidTupleIndex {
         #[help]
@@ -104,39 +95,39 @@ pub enum ErrorKind {
 
 #[derive(Debug, PartialEq, Eq, Hash, Diagnostic, thiserror::Error)]
 pub enum Pattern {
-    #[error("Unexpected {0:?}")]
+    #[error("I found an unexpected char '{0:?}'.")]
-    #[diagnostic(help("Try removing it"))]
+    #[diagnostic(help("Try removing it!"))]
     Char(char),
-    #[error("Unexpected {0}")]
+    #[error("I found an unexpected token '{0}'.")]
-    #[diagnostic(help("Try removing it"))]
+    #[diagnostic(help("Try removing it!"))]
     Token(Token),
-    #[error("Unexpected literal")]
+    #[error("I found an unexpected literal value.")]
-    #[diagnostic(help("Try removing it"))]
+    #[diagnostic(help("Try removing it!"))]
     Literal,
-    #[error("Unexpected type name")]
+    #[error("I found an unexpected type name.")]
-    #[diagnostic(help("Try removing it"))]
+    #[diagnostic(help("Try removing it!"))]
     TypeIdent,
-    #[error("Unexpected indentifier")]
+    #[error("I found an unexpected indentifier.")]
-    #[diagnostic(help("Try removing it"))]
+    #[diagnostic(help("Try removing it!"))]
     TermIdent,
-    #[error("Unexpected end of input")]
+    #[error("I found an unexpected end of input.")]
     End,
-    #[error("Malformed list spread pattern")]
+    #[error("I found a malformed list spread pattern.")]
-    #[diagnostic(help("List spread in matches can\nuse have a discard or var"))]
+    #[diagnostic(help("List spread in matches can use a discard '_' or var."))]
     Match,
-    #[error("Malformed byte literal")]
+    #[error("I found an out-of-bound byte literal.")]
-    #[diagnostic(help("Bytes must be between 0-255"))]
+    #[diagnostic(help("Bytes must be between 0-255."))]
     Byte,
-    #[error("Unexpected pattern")]
+    #[error("I found an unexpected pattern.")]
     #[diagnostic(help(
-        "If no label is provided then only variables\nmatching a field name are allowed"
+        "If no label is provided then only variables\nmatching a field name are allowed."
     ))]
     RecordPunning,
-    #[error("Unexpected label")]
+    #[error("I found an unexpected label.")]
-    #[diagnostic(help("You can only use labels with curly braces"))]
+    #[diagnostic(help("You can only use labels surrounded by curly braces"))]
     Label,
-    #[error("Unexpected hole")]
+    #[error("I found an unexpected discard '_'.")]
-    #[diagnostic(help("You can only use capture syntax with functions not constructors"))]
+    #[diagnostic(help("You can only use capture syntax with functions not constructors."))]
     Discard,
 }
 

crates/aiken-lang/src/tipo/environment.rs

@@ -146,10 +146,9 @@ impl<'a> Environment<'a> {
 
         if let Type::Fn { args, ret } = tipo.deref() {
             return if args.len() != arity {
-                Err(Error::IncorrectArity {
+                Err(Error::IncorrectFunctionCallArity {
                     expected: args.len(),
                     given: arity,
-                    labels: vec![],
                     location: call_location,
                 })
             } else {
@@ -316,9 +315,9 @@ impl<'a> Environment<'a> {
     ) -> Result<&ValueConstructor, Error> {
         match module {
             None => self.scope.get(name).ok_or_else(|| Error::UnknownVariable {
+                location,
                 name: name.to_string(),
                 variables: self.local_value_names(),
-                location,
             }),
 
             Some(m) => {
@@ -1009,10 +1008,10 @@ impl<'a> Environment<'a> {
                 self.ungeneralised_functions.insert(name.to_string());
 
                 // Create the field map so we can reorder labels for usage of this function
-                let mut field_map = FieldMap::new(args.len());
+                let mut field_map = FieldMap::new(args.len(), true);
 
                 for (i, arg) in args.iter().enumerate() {
-                    field_map.insert(arg.arg_name.get_label().clone(), i, location)?;
+                    field_map.insert(arg.arg_name.get_label().clone(), i, &arg.location)?;
                 }
                 let field_map = field_map.into_option();
 
@@ -1077,7 +1076,6 @@ impl<'a> Environment<'a> {
             }
 
             Definition::DataType(DataType {
-                location,
                 public,
                 opaque,
                 name,
@@ -1115,14 +1113,17 @@ impl<'a> Environment<'a> {
                 for constructor in constructors {
                     assert_unique_value_name(names, &constructor.name, &constructor.location)?;
 
-                    let mut field_map = FieldMap::new(constructor.arguments.len());
+                    let mut field_map = FieldMap::new(constructor.arguments.len(), false);
 
                     let mut args_types = Vec::with_capacity(constructor.arguments.len());
 
                     for (
                         i,
                         RecordConstructorArg {
-                            label, annotation, ..
+                            label,
+                            annotation,
+                            location,
+                            ..
                         },
                     ) in constructor.arguments.iter().enumerate()
                     {
@@ -1593,16 +1594,13 @@ fn assert_unique_const_name<'a>(
     }
 }
 
-pub(super) fn assert_no_labeled_arguments<A>(args: &[CallArg<A>]) -> Result<(), Error> {
+pub(super) fn assert_no_labeled_arguments<A>(args: &[CallArg<A>]) -> Option<(Span, String)> {
     for arg in args {
         if let Some(label) = &arg.label {
-            return Err(Error::UnexpectedLabeledArg {
+            return Some((arg.location, label.to_string()));
-                location: arg.location,
-                label: label.to_string(),
-            });
         }
     }
-    Ok(())
+    None
 }
 
 pub(super) fn collapse_links(t: Arc<Type>) -> Arc<Type> {

crates/aiken-lang/src/tipo/expr.rs

@@ -111,7 +111,9 @@ impl<'a, 'b> ExprTyper<'a, 'b> {
             Some(field_map) => field_map.reorder(&mut args, location)?,
 
             // The fun has no field map and so we error if arguments have been labelled
-            None => assert_no_labeled_arguments(&args)?,
+            None => assert_no_labeled_arguments(&args)
+                .map(|(location, label)| Err(Error::UnexpectedLabeledArg { location, label }))
+                .unwrap_or(Ok(()))?,
         }
 
         // Extract the type of the fun, ensuring it actually is a function
@@ -499,7 +501,7 @@ impl<'a, 'b> ExprTyper<'a, 'b> {
                 None => {
                     panic!("Failed to lookup record field after successfully inferring that field",)
                 }
-                Some(p) => arguments.push(TypedRecordUpdateArg {
+                Some((p, _)) => arguments.push(TypedRecordUpdateArg {
                     location,
                     label: label.to_string(),
                     value,
@@ -1350,7 +1352,11 @@ impl<'a, 'b> ExprTyper<'a, 'b> {
                     Some(field_map) => field_map.reorder(&mut args, location)?,
 
                     // The fun has no field map and so we error if arguments have been labelled
-                    None => assert_no_labeled_arguments(&args)?,
+                    None => assert_no_labeled_arguments(&args)
+                        .map(|(location, label)| {
+                            Err(Error::UnexpectedLabeledArg { location, label })
+                        })
+                        .unwrap_or(Ok(()))?,
                 }
 
                 let (mut args_types, return_type) = self.environment.match_fun_type(
@@ -1723,7 +1729,10 @@ impl<'a, 'b> ExprTyper<'a, 'b> {
                     Ok(elems[index].clone())
                 }
             }
-            _ => Err(Error::NotATuple { location }),
+            _ => Err(Error::NotATuple {
+                location,
+                tipo: tuple.tipo(),
+            }),
         }?;
 
         Ok(TypedExpr::TupleIndex {

crates/aiken-lang/src/tipo/fields.rs

@@ -8,23 +8,34 @@ use crate::ast::{CallArg, Span};
 #[derive(Debug, Clone, PartialEq, Eq)]
 pub struct FieldMap {
     pub arity: usize,
-    pub fields: HashMap<String, usize>,
+    pub fields: HashMap<String, (usize, Span)>,
+    pub is_function: bool,
 }
 
 impl FieldMap {
-    pub fn new(arity: usize) -> Self {
+    pub fn new(arity: usize, is_function: bool) -> Self {
         Self {
             arity,
             fields: HashMap::new(),
+            is_function,
         }
     }
 
     pub fn insert(&mut self, label: String, index: usize, location: &Span) -> Result<(), Error> {
-        match self.fields.insert(label.clone(), index) {
+        match self.fields.insert(label.clone(), (index, *location)) {
-            Some(_) => Err(Error::DuplicateField {
+            Some((_, location_other)) => {
-                label,
+                if self.is_function {
-                location: *location,
+                    Err(Error::DuplicateArgument {
-            }),
+                        label,
+                        locations: vec![*location, location_other],
+                    })
+                } else {
+                    Err(Error::DuplicateField {
+                        label,
+                        locations: vec![*location, location_other],
+                    })
+                }
+            }
             None => Ok(()),
         }
     }
@@ -40,12 +51,12 @@ impl FieldMap {
     /// Reorder an argument list so that labelled fields supplied out-of-order are
     /// in the correct order.
     pub fn reorder<A>(&self, args: &mut [CallArg<A>], location: Span) -> Result<(), Error> {
-        let mut labeled_arguments_given = false;
+        let mut last_labeled_arguments_given: Option<&CallArg<A>> = None;
         let mut seen_labels = std::collections::HashSet::new();
         let mut unknown_labels = Vec::new();
 
         if self.arity != args.len() {
-            return Err(Error::IncorrectArity {
+            return Err(Error::IncorrectFieldsArity {
                 labels: self.incorrect_arity_labels(args),
                 location,
                 expected: self.arity,
@@ -56,13 +67,14 @@ impl FieldMap {
         for arg in args.iter() {
             match &arg.label {
                 Some(_) => {
-                    labeled_arguments_given = true;
+                    last_labeled_arguments_given = Some(arg);
                 }
 
                 None => {
-                    if labeled_arguments_given {
+                    if let Some(label) = last_labeled_arguments_given {
                         return Err(Error::PositionalArgumentAfterLabeled {
                             location: arg.location,
+                            labeled_arg_location: label.location,
                         });
                     }
                 }
@@ -90,7 +102,7 @@ impl FieldMap {
                 }
             };
 
-            let position = match self.fields.get(label) {
+            let (position, other_location) = match self.fields.get(label) {
                 None => {
                     unknown_labels.push((label.clone(), location));
 
@@ -110,7 +122,7 @@ impl FieldMap {
             } else {
                 if seen_labels.contains(label) {
                     return Err(Error::DuplicateArgument {
-                        location,
+                        locations: vec![location, other_location],
                         label: label.to_string(),
                     });
                 }

crates/aiken-lang/src/tipo/pattern.rs

@@ -357,8 +357,7 @@ impl<'a, 'b> PatternTyper<'a, 'b> {
             Pattern::Tuple { elems, location } => match collapse_links(tipo.clone()).deref() {
                 Type::Tuple { elems: type_elems } => {
                     if elems.len() != type_elems.len() {
-                        return Err(Error::IncorrectArity {
+                        return Err(Error::IncorrectTupleArity {
-                            labels: vec![],
                             location,
                             expected: type_elems.len(),
                             given: elems.len(),
@@ -483,7 +482,18 @@ impl<'a, 'b> PatternTyper<'a, 'b> {
                     }
 
                     // The fun has no field map and so we error if arguments have been labelled
-                    None => assert_no_labeled_arguments(&pattern_args)?,
+                    None => assert_no_labeled_arguments(&pattern_args)
+                        .map(|(location, label)| {
+                            Err(Error::UnexpectedLabeledArgInPattern {
+                                location,
+                                label,
+                                name: name.clone(),
+                                args: pattern_args.clone(),
+                                module: module.clone(),
+                                with_spread,
+                            })
+                        })
+                        .unwrap_or(Ok(()))?,
                 }
 
                 let constructor_typ = cons.tipo.clone();
@@ -542,11 +552,13 @@ impl<'a, 'b> PatternTyper<'a, 'b> {
                                 is_record,
                             })
                         } else {
-                            Err(Error::IncorrectArity {
+                            Err(Error::IncorrectPatternArity {
-                                labels: vec![],
                                 location,
-                                expected: args.len(),
+                                given: pattern_args,
-                                given: pattern_args.len(),
+                                expected: 0,
+                                name: name.clone(),
+                                module: module.clone(),
+                                is_record,
                             })
                         }
                     }
@@ -570,11 +582,13 @@ impl<'a, 'b> PatternTyper<'a, 'b> {
                                 is_record,
                             })
                         } else {
-                            Err(Error::IncorrectArity {
+                            Err(Error::IncorrectPatternArity {
-                                labels: vec![],
                                 location,
+                                given: pattern_args,
                                 expected: 0,
-                                given: pattern_args.len(),
+                                name: name.clone(),
+                                module: module.clone(),
+                                is_record,
                             })
                         }
                     }

crates/aiken-lang/src/uplc.rs

@@ -972,7 +972,8 @@ impl<'a> CodeGenerator<'a> {
                         .iter()
                         .map(|item| {
                             let label = item.label.clone().unwrap_or_default();
-                            let field_index = field_map.fields.get(&label).unwrap_or(&0);
+                            let field_index =
+                                field_map.fields.get(&label).map(|x| &x.0).unwrap_or(&0);
                             let (discard, var_name) = match &item.value {
                                 Pattern::Var { name, .. } => (false, name.clone()),
                                 Pattern::Discard { .. } => (true, "".to_string()),
@@ -1316,7 +1317,8 @@ impl<'a> CodeGenerator<'a> {
                         .iter()
                         .map(|item| {
                             let label = item.label.clone().unwrap_or_default();
-                            let field_index = field_map.fields.get(&label).unwrap_or(&0);
+                            let field_index =
+                                field_map.fields.get(&label).map(|x| &x.0).unwrap_or(&0);
                             let (discard, var_name) = match &item.value {
                                 Pattern::Var { name, .. } => (false, name.clone()),
                                 Pattern::Discard { .. } => (true, "".to_string()),
@@ -2031,7 +2033,11 @@ impl<'a> CodeGenerator<'a> {
                                 for field in field_map
                                     .fields
                                     .iter()
-                                    .sorted_by(|item1, item2| item1.1.cmp(item2.1))
+                                    .sorted_by(|item1, item2| {
+                                        let (a, _) = item1.1;
+                                        let (b, _) = item2.1;
+                                        a.cmp(b)
+                                    })
                                     .zip(&args_type)
                                     .rev()
                                 {
@@ -2092,7 +2098,11 @@ impl<'a> CodeGenerator<'a> {
                                 for field in field_map
                                     .fields
                                     .iter()
-                                    .sorted_by(|item1, item2| item1.1.cmp(item2.1))
+                                    .sorted_by(|item1, item2| {
+                                        let (a, _) = item1.1;
+                                        let (b, _) = item2.1;
+                                        a.cmp(b)
+                                    })
                                     .rev()
                                 {
                                     term = Term::Lambda {

crates/aiken-project/src/error.rs

@@ -18,17 +18,17 @@ use zip_extract::ZipExtractError;
 #[allow(dead_code)]
 #[derive(thiserror::Error)]
 pub enum Error {
-    #[error("Duplicate module\n\n{module}")]
+    #[error("I just found two modules with the same name: '{module}'")]
     DuplicateModule {
         module: String,
         first: PathBuf,
         second: PathBuf,
     },
 
-    #[error("File operation failed")]
+    #[error("Some operation on the file-system did fail.")]
     FileIo { error: io::Error, path: PathBuf },
 
-    #[error("Source code incorrectly formatted")]
+    #[error("I found some files with incorrectly formatted source code.")]
     Format { problem_files: Vec<Unformatted> },
 
     #[error(transparent)]
@@ -52,29 +52,26 @@ pub enum Error {
         help: String,
     },
 
-    #[error("Missing 'aiken.toml' manifest in {path}")]
+    #[error("I couldn't find any 'aiken.toml' manifest in {path}.")]
     MissingManifest { path: PathBuf },
 
-    #[error("Cyclical module imports")]
+    #[error("I just found a cycle in module hierarchy!")]
     ImportCycle { modules: Vec<String> },
 
     /// Useful for returning many [`Error::Parse`] at once
     #[error("A list of errors")]
     List(Vec<Self>),
 
-    #[error("Parsing")]
+    #[error("While parsing files...")]
     Parse {
         path: PathBuf,
-
         src: String,
-
         named: NamedSource,
-
         #[source]
         error: Box<ParseError>,
     },
 
-    #[error("Checking")]
+    #[error("While trying to make sense of your code...")]
     Type {
         path: PathBuf,
         src: String,
@@ -246,7 +243,10 @@ impl Diagnostic for Error {
             Error::ImportCycle { .. } => Some(Box::new("aiken::module::cyclical")),
             Error::List(_) => None,
             Error::Parse { .. } => Some(Box::new("aiken::parser")),
-            Error::Type { .. } => Some(Box::new("aiken::check")),
+            Error::Type { error, .. } => Some(Box::new(format!(
+                "err::aiken::check{}",
+                error.code().map(|s| format!("::{s}")).unwrap_or_default()
+            ))),
             Error::StandardIo(_) => None,
             Error::MissingManifest { .. } => None,
             Error::TomlLoading { .. } => Some(Box::new("aiken::loading::toml")),
@@ -368,6 +368,27 @@ impl Diagnostic for Error {
             Error::JoinError(_) => None,
         }
     }
+
+    fn url<'a>(&'a self) -> Option<Box<dyn Display + 'a>> {
+        match self {
+            Error::DuplicateModule { .. } => None,
+            Error::FileIo { .. } => None,
+            Error::ImportCycle { .. } => None,
+            Error::List { .. } => None,
+            Error::Parse { .. } => None,
+            Error::Type { error, .. } => error.url(),
+            Error::StandardIo(_) => None,
+            Error::MissingManifest { .. } => None,
+            Error::TomlLoading { .. } => None,
+            Error::Format { .. } => None,
+            Error::ValidatorMustReturnBool { .. } => None,
+            Error::WrongValidatorArity { .. } => None,
+            Error::TestFailure { .. } => None,
+            Error::Http { .. } => None,
+            Error::ZipExtract { .. } => None,
+            Error::JoinError { .. } => None,
+        }
+    }
 }
 
 #[derive(thiserror::Error)]