Begin adding fancy errors

Cargo.lock

@@ -11,6 +11,16 @@ dependencies = [
  "memchr",
 ]
 
+[[package]]
+name = "annotate-snippets"
+version = "0.11.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "24e35ed54e5ea7997c14ed4c70ba043478db1112e98263b3b035907aa197d991"
+dependencies = [
+ "anstyle",
+ "unicode-width",
+]
+
 [[package]]
 name = "anstream"
 version = "0.6.13"
@@ -140,6 +150,7 @@ checksum = "248e3bacc7dc6baa3b21e405ee045c3047101a49145e7e9eca583ab4c2ca5345"
 name = "dust-lang"
 version = "0.5.0"
 dependencies = [
+ "annotate-snippets",
  "env_logger",
  "rand",
  "rayon",
@@ -394,6 +405,12 @@ version = "1.0.12"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3354b9ac3fae1ff6755cb6db53683adb661634f67557942dea4facebec0fee4b"
 
+[[package]]
+name = "unicode-width"
+version = "0.1.13"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0336d538f7abc86d282a4189614dfaa90810dfc2c6f6427eaf88e16311dd225d"
+
 [[package]]
 name = "utf8parse"
 version = "0.2.1"

dust-lang/Cargo.toml

@@ -9,6 +9,7 @@ readme.workspace = true
 repository.workspace = true
 
 [dependencies]
+annotate-snippets = "0.11.4"
 env_logger = "0.11.3"
 rand = "0.8.5"
 rayon = "1.9.0"

dust-lang/src/analyzer.rs

@@ -85,11 +85,13 @@ impl<'a> Analyzer<'a> {
                     (Some(Type::Integer), _) | (Some(Type::Float), _) | (Some(Type::String), _) => {
                         return Err(AnalyzerError::ExpectedIntegerFloatOrString {
                             actual: right.as_ref().clone(),
+                            position: right.position,
                         });
                     }
                     _ => {
                         return Err(AnalyzerError::ExpectedIntegerFloatOrString {
                             actual: left.as_ref().clone(),
+                            position: left.position,
                         });
                     }
                 }
@@ -103,6 +105,7 @@ impl<'a> Analyzer<'a> {
                 } else {
                     return Err(AnalyzerError::ExpectedIdentifier {
                         actual: left.as_ref().clone(),
+                        position: left.position,
                     });
                 }
 
@@ -116,12 +119,14 @@ impl<'a> Analyzer<'a> {
                 } else {
                     return Err(AnalyzerError::ExpectedIdentifier {
                         actual: function.as_ref().clone(),
+                        position: function.position,
                     });
                 }
             }
             Statement::Identifier(_) => {
                 return Err(AnalyzerError::UnexpectedIdentifier {
                     identifier: node.clone(),
+                    position: node.position,
                 });
             }
             Statement::List(statements) => {
@@ -136,6 +141,7 @@ impl<'a> Analyzer<'a> {
                 } else {
                     return Err(AnalyzerError::ExpectedIntegerOrFloat {
                         actual: left.as_ref().clone(),
+                        position: left.position,
                     });
                 }
 
@@ -145,6 +151,7 @@ impl<'a> Analyzer<'a> {
                 } else {
                     return Err(AnalyzerError::ExpectedIntegerOrFloat {
                         actual: right.as_ref().clone(),
+                        position: right.position,
                     });
                 }
 
@@ -159,6 +166,7 @@ impl<'a> Analyzer<'a> {
                 } else {
                     return Err(AnalyzerError::ExpectedIdentifierOrValue {
                         actual: left.as_ref().clone(),
+                        position: left.position,
                     });
                 }
 
@@ -168,6 +176,7 @@ impl<'a> Analyzer<'a> {
                         } else {
                             return Err(AnalyzerError::ExpectedIntegerOrFloat {
                                 actual: left.as_ref().clone(),
+                                position: left.position,
                             });
                         }
                     }
@@ -183,13 +192,13 @@ impl<'a> Analyzer<'a> {
 
 #[derive(Clone, Debug, PartialEq)]
 pub enum AnalyzerError {
-    ExpectedBoolean { actual: Node },
+    ExpectedBoolean { actual: Node, position: Span },
-    ExpectedFunction { actual: Node },
+    ExpectedFunction { actual: Node, position: Span },
-    ExpectedIdentifier { actual: Node },
+    ExpectedIdentifier { actual: Node, position: Span },
-    ExpectedIdentifierOrValue { actual: Node },
+    ExpectedIdentifierOrValue { actual: Node, position: Span },
-    ExpectedIntegerOrFloat { actual: Node },
+    ExpectedIntegerOrFloat { actual: Node, position: Span },
-    ExpectedIntegerFloatOrString { actual: Node },
+    ExpectedIntegerFloatOrString { actual: Node, position: Span },
-    UnexpectedIdentifier { identifier: Node },
+    UnexpectedIdentifier { identifier: Node, position: Span },
 }
 
 impl Error for AnalyzerError {}
@@ -197,25 +206,25 @@ impl Error for AnalyzerError {}
 impl Display for AnalyzerError {
     fn fmt(&self, f: &mut Formatter) -> fmt::Result {
         match self {
-            AnalyzerError::ExpectedBoolean { actual } => {
+            AnalyzerError::ExpectedBoolean { actual, .. } => {
                 write!(f, "Expected boolean, found {}", actual)
             }
-            AnalyzerError::ExpectedFunction { actual } => {
+            AnalyzerError::ExpectedFunction { actual, .. } => {
                 write!(f, "Expected function, found {}", actual)
             }
-            AnalyzerError::ExpectedIdentifier { actual } => {
+            AnalyzerError::ExpectedIdentifier { actual, .. } => {
                 write!(f, "Expected identifier, found {}", actual)
             }
-            AnalyzerError::ExpectedIdentifierOrValue { actual } => {
+            AnalyzerError::ExpectedIdentifierOrValue { actual, .. } => {
                 write!(f, "Expected identifier or value, found {}", actual)
             }
-            AnalyzerError::ExpectedIntegerOrFloat { actual } => {
+            AnalyzerError::ExpectedIntegerOrFloat { actual, .. } => {
                 write!(f, "Expected integer or float, found {}", actual)
             }
-            AnalyzerError::ExpectedIntegerFloatOrString { actual } => {
+            AnalyzerError::ExpectedIntegerFloatOrString { actual, .. } => {
                 write!(f, "Expected integer, float, or string, found {}", actual)
             }
-            AnalyzerError::UnexpectedIdentifier { identifier } => {
+            AnalyzerError::UnexpectedIdentifier { identifier, .. } => {
                 write!(f, "Unexpected identifier {}", identifier)
             }
         }
@@ -246,7 +255,8 @@ mod tests {
         assert_eq!(
             analyzer.analyze(),
             Err(AnalyzerError::ExpectedIntegerFloatOrString {
-                actual: Node::new(Statement::Constant(Value::float(1.0)), (1, 2))
+                actual: Node::new(Statement::Constant(Value::float(1.0)), (1, 2)),
+                position: (1, 2)
             })
         )
     }
@@ -269,7 +279,8 @@ mod tests {
         assert_eq!(
             analyzer.analyze(),
             Err(AnalyzerError::ExpectedIntegerFloatOrString {
-                actual: Node::new(Statement::Constant(Value::boolean(true)), (0, 1))
+                actual: Node::new(Statement::Constant(Value::boolean(true)), (0, 1)),
+                position: (0, 1)
             })
         )
     }
@@ -299,7 +310,8 @@ mod tests {
         assert_eq!(
             analyzer.analyze(),
             Err(AnalyzerError::ExpectedIntegerOrFloat {
-                actual: Node::new(Statement::Constant(Value::boolean(true)), (0, 1))
+                actual: Node::new(Statement::Constant(Value::boolean(true)), (0, 1)),
+                position: (0, 1)
             })
         )
     }
@@ -328,7 +340,8 @@ mod tests {
         assert_eq!(
             analyzer.analyze(),
             Err(AnalyzerError::ExpectedIntegerOrFloat {
-                actual: Node::new(Statement::Constant(Value::boolean(true)), (0, 1))
+                actual: Node::new(Statement::Constant(Value::boolean(true)), (0, 1)),
+                position: (0, 1)
             })
         )
     }
@@ -354,7 +367,8 @@ mod tests {
         assert_eq!(
             analyzer.analyze(),
             Err(AnalyzerError::ExpectedIntegerOrFloat {
-                actual: Node::new(Statement::Constant(Value::boolean(false)), (1, 2))
+                actual: Node::new(Statement::Constant(Value::boolean(false)), (1, 2)),
+                position: (1, 2)
             })
         )
     }
@@ -377,7 +391,8 @@ mod tests {
         assert_eq!(
             analyzer.analyze(),
             Err(AnalyzerError::ExpectedIdentifier {
-                actual: Node::new(Statement::Constant(Value::integer(1)), (0, 1))
+                actual: Node::new(Statement::Constant(Value::integer(1)), (0, 1)),
+                position: (0, 1)
             })
         )
     }
@@ -397,7 +412,8 @@ mod tests {
         assert_eq!(
             analyzer.analyze(),
             Err(AnalyzerError::UnexpectedIdentifier {
-                identifier: Node::new(Statement::Identifier(Identifier::new("x")), (0, 1))
+                identifier: Node::new(Statement::Identifier(Identifier::new("x")), (0, 1)),
+                position: (0, 1)
             })
         )
     }

dust-lang/src/dust_error.rs

@@ -1,6 +1,7 @@
+use annotate_snippets::{Level, Renderer, Snippet};
 use std::{error::Error, fmt::Display};
 
-use crate::VmError;
+use crate::{AnalyzerError, VmError};
 
 #[derive(Debug, Clone, PartialEq)]
 pub struct DustError<'src> {
@@ -8,6 +9,51 @@ pub struct DustError<'src> {
     source: &'src str,
 }
 
+impl<'src> DustError<'src> {
+    pub fn new(vm_error: VmError, source: &'src str) -> Self {
+        Self { vm_error, source }
+    }
+
+    pub fn report(&self) -> String {
+        let title = match &self.vm_error {
+            VmError::AnaylyzerError(_) => "Analyzer error",
+            VmError::ParseError(_) => "Parse error",
+            VmError::ValueError(_) => "Value error",
+            VmError::BuiltInFunctionCallError(_) => "Runtime error",
+            _ => "Analysis Failure",
+        };
+        let span = match &self.vm_error {
+            VmError::AnaylyzerError(analyzer_error) => match analyzer_error {
+                AnalyzerError::ExpectedBoolean { position, .. } => position,
+                AnalyzerError::ExpectedFunction { position, .. } => position,
+                AnalyzerError::ExpectedIdentifier { position, .. } => position,
+                AnalyzerError::ExpectedIdentifierOrValue { position, .. } => position,
+                AnalyzerError::ExpectedIntegerOrFloat { position, .. } => position,
+                AnalyzerError::ExpectedIntegerFloatOrString { position, .. } => position,
+                AnalyzerError::UnexpectedIdentifier { position, .. } => position,
+            },
+            VmError::ParseError(_) => todo!(),
+            VmError::ValueError(_) => todo!(),
+            VmError::BuiltInFunctionCallError(_) => todo!(),
+            VmError::ExpectedIdentifier { position } => position,
+            VmError::ExpectedIdentifierOrInteger { position } => position,
+            VmError::ExpectedInteger { position } => position,
+            VmError::ExpectedFunction { position, .. } => position,
+            VmError::ExpectedList { position } => position,
+            VmError::ExpectedValue { position } => position,
+        };
+        let label = self.vm_error.to_string();
+
+        let message = Level::Error.title(title).snippet(
+            Snippet::source(self.source).annotation(Level::Info.span(span.0..span.1).label(&label)),
+        );
+
+        let renderer = Renderer::styled();
+
+        format!("{}", renderer.render(message))
+    }
+}
+
 impl Error for DustError<'_> {
     fn source(&self) -> Option<&(dyn Error + 'static)> {
         Some(&self.vm_error)

dust-lang/src/lib.rs

@@ -20,6 +20,7 @@ pub mod vm;
 pub use abstract_tree::{AbstractSyntaxTree, Node, Statement};
 pub use analyzer::{analyze, Analyzer, AnalyzerError};
 pub use built_in_function::{BuiltInFunction, BuiltInFunctionError};
+pub use dust_error::DustError;
 pub use identifier::Identifier;
 pub use lex::{lex, LexError, Lexer};
 pub use parse::{parse, ParseError, Parser};

dust-lang/src/parse.rs

@@ -235,7 +235,7 @@ impl<'src> Parser<'src> {
                 } else {
                     Err(ParseError::ExpectedClosingParenthesis {
                         actual: self.current.0.to_owned(),
-                        span: self.current.1,
+                        position: self.current.1,
                     })
                 }
             }
@@ -265,7 +265,7 @@ impl<'src> Parser<'src> {
                     } else {
                         return Err(ParseError::ExpectedClosingSquareBrace {
                             actual: self.current.0.to_owned(),
-                            span: self.current.1,
+                            position: self.current.1,
                         });
                     }
                 }
@@ -290,7 +290,7 @@ impl<'src> Parser<'src> {
                 } else {
                     return Err(ParseError::ExpectedOpeningParenthesis {
                         actual: self.current.0.to_owned(),
-                        span: self.current.1,
+                        position: self.current.1,
                     });
                 }
 
@@ -316,7 +316,7 @@ impl<'src> Parser<'src> {
                     } else {
                         return Err(ParseError::ExpectedClosingParenthesis {
                             actual: self.current.0.to_owned(),
-                            span: self.current.1,
+                            position: self.current.1,
                         });
                     }
                 }
@@ -349,9 +349,9 @@ impl<'src> Parser<'src> {
 pub enum ParseError {
     LexError(LexError),
 
-    ExpectedClosingParenthesis { actual: TokenOwned, span: Span },
+    ExpectedClosingParenthesis { actual: TokenOwned, position: Span },
-    ExpectedClosingSquareBrace { actual: TokenOwned, span: Span },
+    ExpectedClosingSquareBrace { actual: TokenOwned, position: Span },
-    ExpectedOpeningParenthesis { actual: TokenOwned, span: Span },
+    ExpectedOpeningParenthesis { actual: TokenOwned, position: Span },
     UnexpectedToken(TokenOwned),
 }
 
@@ -368,22 +368,16 @@ impl Display for ParseError {
     fn fmt(&self, f: &mut Formatter) -> fmt::Result {
         match self {
             Self::LexError(error) => write!(f, "{}", error),
-            Self::ExpectedClosingParenthesis { actual, span } => write!(
+            Self::ExpectedClosingParenthesis { actual, .. } => {
-                f,
+                write!(f, "Expected closing parenthesis, found {actual}",)
-                "Expected closing parenthesis, found {} at {:?}",
+            }
-                actual, span
+            Self::ExpectedClosingSquareBrace { actual, .. } => {
-            ),
+                write!(f, "Expected closing square brace, found {actual}",)
-            Self::ExpectedClosingSquareBrace { actual, span } => write!(
+            }
-                f,
+            Self::ExpectedOpeningParenthesis { actual, .. } => {
-                "Expected closing square brace, found {:?} at {:?}",
+                write!(f, "Expected opening parenthesis, found {actual}",)
-                actual, span
+            }
-            ),
+            Self::UnexpectedToken(actual) => write!(f, "Unexpected token {actual}"),
-            Self::ExpectedOpeningParenthesis { actual, span } => write!(
-                f,
-                "Expected opening parenthesis, found {:?} at {:?}",
-                actual, span
-            ),
-            Self::UnexpectedToken(actual) => write!(f, "Unexpected token {:?}", actual),
         }
     }
 }

dust-lang/src/vm.rs

@@ -250,7 +250,7 @@ pub enum VmError {
 
     // Anaylsis Failures
     // These should be prevented by running the analyzer before the VM
-    BuiltInFunctionCallFailed(BuiltInFunctionError),
+    BuiltInFunctionCallError(BuiltInFunctionError),
     ExpectedIdentifier { position: Span },
     ExpectedIdentifierOrInteger { position: Span },
     ExpectedInteger { position: Span },
@@ -261,7 +261,7 @@ pub enum VmError {
 
 impl From<BuiltInFunctionError> for VmError {
     fn from(v: BuiltInFunctionError) -> Self {
-        Self::BuiltInFunctionCallFailed(v)
+        Self::BuiltInFunctionCallError(v)
     }
 }
 
@@ -289,7 +289,7 @@ impl Error for VmError {
             Self::AnaylyzerError(analyzer_error) => Some(analyzer_error),
             Self::ParseError(parse_error) => Some(parse_error),
             Self::ValueError(value_error) => Some(value_error),
-            Self::BuiltInFunctionCallFailed(built_in_function_error) => {
+            Self::BuiltInFunctionCallError(built_in_function_error) => {
                 Some(built_in_function_error)
             }
             _ => None,
@@ -303,7 +303,7 @@ impl Display for VmError {
             Self::AnaylyzerError(analyzer_error) => write!(f, "{}", analyzer_error),
             Self::ParseError(parse_error) => write!(f, "{}", parse_error),
             Self::ValueError(value_error) => write!(f, "{}", value_error),
-            Self::BuiltInFunctionCallFailed(built_in_function_error) => {
+            Self::BuiltInFunctionCallError(built_in_function_error) => {
                 write!(f, "{}", built_in_function_error)
             }
             Self::ExpectedFunction { actual, position } => {

dust-shell/src/main.rs

@@ -1,7 +1,7 @@
 use std::{collections::HashMap, fs::read_to_string};
 
 use clap::Parser;
-use dust_lang::run;
+use dust_lang::{run, DustError, Identifier, Value};
 
 #[derive(Parser)]
 struct Cli {
@@ -15,22 +15,24 @@ fn main() {
     let args = Cli::parse();
     let mut variables = HashMap::new();
 
-    let result = if let Some(command) = &args.command {
+    if let Some(command) = &args.command {
-        run(command, &mut variables)
+        run_and_display_errors(command, &mut variables);
     } else if let Some(path) = &args.path {
-        let content = read_to_string(path).unwrap();
+        let source = read_to_string(path).expect("Failed to read file");
 
-        run(&content, &mut variables)
+        run_and_display_errors(&source, &mut variables)
     } else {
         panic!("No command or path provided");
     };
+}
 
-    match result {
+fn run_and_display_errors(source: &str, variables: &mut HashMap<Identifier, Value>) {
+    match run(source, variables) {
         Ok(return_value) => {
             if let Some(value) = return_value {
                 println!("{}", value);
             }
         }
-        Err(error) => eprintln!("{}", error),
+        Err(error) => eprintln!("{}", DustError::new(error, source).report()),
     }
 }

rust-toolchain

@@ -0,0 +1 @@
+nightly