Introduce Diagnostic trait and remove error rendering in public API

crates/codegen/runtime/cargo/Cargo.toml

@@ -12,7 +12,7 @@ anyhow = { workspace = true }
 codegen_runtime_generator = { workspace = true }
 
 [dependencies]
-ariadne = { workspace = true }
+ariadne = { workspace = true, optional = true }
 napi = { workspace = true, optional = true }
 napi-derive = { workspace = true, optional = true }
 nom = { workspace = true }
@@ -28,6 +28,8 @@ thiserror = { workspace = true }
 [features]
 default = ["slang_napi_interfaces"]
 slang_napi_interfaces = ["dep:napi", "dep:napi-derive", "dep:serde_json"]
+# Only used by the `slang_solidity` CLI
+__private_ariadne = ["dep:ariadne"]
 
 [lints]
 workspace = true

crates/codegen/runtime/cargo/src/runtime/diagnostic.rs

@@ -0,0 +1,65 @@
+use std::borrow::Cow;
+use std::error::Error;
+
+use crate::text_index::TextRange;
+
+#[repr(u8)]
+pub enum Severity {
+    Error = 1,
+    Warning = 2,
+    Information = 3,
+    Hint = 4,
+}
+
+pub trait Diagnostic: Error {
+    fn range(&self) -> TextRange;
+    fn code(&self) -> Option<Cow<'_, str>> {
+        None
+    }
+    fn severity(&self) -> Severity;
+    fn message(&self) -> String;
+}
+
+#[cfg(feature = "__private_ariadne")]
+pub fn render<D: Diagnostic>(error: &D, source_id: &str, source: &str, with_color: bool) -> String {
+    use ariadne::{Color, Config, Label, Report, ReportKind, Source};
+
+    use crate::text_index::TextRangeExtensions as _;
+
+    let kind = match error.severity() {
+        Severity::Error => ReportKind::Error,
+        Severity::Warning => ReportKind::Warning,
+        Severity::Information => ReportKind::Advice,
+        Severity::Hint => ReportKind::Advice,
+    };
+
+    let color = if with_color { Color::Red } else { Color::Unset };
+
+    let message = error.message();
+
+    if source.is_empty() {
+        return format!("{kind}: {message}\n   ─[{source_id}:0:0]");
+    }
+
+    let range = error.range().char();
+
+    let report = Report::build(kind, source_id, range.start)
+        .with_config(Config::default().with_color(with_color))
+        .with_message(message)
+        .with_label(
+            Label::new((source_id, range))
+                .with_color(color)
+                .with_message("Error occurred here."),
+        )
+        .finish();
+
+    let mut result = vec![];
+    report
+        .write((source_id, Source::from(&source)), &mut result)
+        .expect("Failed to write report");
+
+    return String::from_utf8(result)
+        .expect("Failed to convert report to utf8")
+        .trim()
+        .to_string();
+}

crates/codegen/runtime/cargo/src/runtime/mod.rs

@@ -4,6 +4,7 @@ pub(crate) mod lexer;
 
 pub mod cst;
 pub mod cursor;
+pub mod diagnostic;
 pub mod parse_error;
 pub mod parse_output;
 pub mod query;

crates/codegen/runtime/cargo/src/runtime/napi_interface/diagnostic.rs

@@ -0,0 +1,51 @@
+use napi_derive::napi;
+
+use crate::napi_interface::text_index::TextRange;
+
+/// Severity of the compiler diagnostic.
+///
+/// Explicitly compatible with the LSP protocol.
+#[napi(namespace = "diagnostic")]
+pub enum Severity {
+    Error = 1,
+    Warning = 2,
+    Information = 3,
+    Hint = 4,
+}
+
+impl From<crate::diagnostic::Severity> for Severity {
+    fn from(value: crate::diagnostic::Severity) -> Severity {
+        match value {
+            crate::diagnostic::Severity::Error => Self::Error,
+            crate::diagnostic::Severity::Warning => Self::Warning,
+            crate::diagnostic::Severity::Information => Self::Information,
+            crate::diagnostic::Severity::Hint => Self::Hint,
+        }
+    }
+}
+
+#[napi(namespace = "diagnostic")]
+pub struct Diagnostic(pub(crate) Box<dyn crate::diagnostic::Diagnostic>);
+
+#[napi(namespace = "diagnostic")]
+impl Diagnostic {
+    #[napi]
+    pub fn severity(&self) -> Severity {
+        self.0.severity().into()
+    }
+
+    #[napi(ts_return_type = "text_index.TextRange")]
+    pub fn text_range(&self) -> TextRange {
+        self.0.range().into()
+    }
+
+    #[napi]
+    pub fn message(&self) -> String {
+        self.0.message()
+    }
+
+    #[napi]
+    pub fn code(&self) -> String {
+        self.0.code().unwrap_or_default().into_owned()
+    }
+}

crates/codegen/runtime/cargo/src/runtime/napi_interface/mod.rs

@@ -1,5 +1,6 @@
 pub mod cst;
 pub mod cursor;
+pub mod diagnostic;
 pub mod parse_error;
 pub mod parse_output;
 pub mod query;

crates/codegen/runtime/cargo/src/runtime/napi_interface/parse_error.rs

@@ -4,6 +4,7 @@
 use napi_derive::napi;
 use text_index::TextRange;
 
+use crate::napi_interface::diagnostic::Diagnostic;
 use crate::napi_interface::{text_index, RustParseError};
 
 #[napi(namespace = "parse_error")]
@@ -23,8 +24,10 @@ impl ParseError {
         self.0.text_range().clone().into()
     }
 
-    #[napi(catch_unwind)]
-    pub fn to_error_report(&self, source_id: String, source: String, with_color: bool) -> String {
-        self.0.to_error_report(&source_id, &source, with_color)
+    #[napi(ts_return_type = "diagnostic.Diagnostic", catch_unwind)]
+    pub fn to_diagnostic(&self) -> Diagnostic {
+        // TODO: Figure out if we can auto-gen Diagnostics methods
+        // in TS for this implementor rather than having to clone here
+        Diagnostic(Box::new(self.0.clone()))
     }
 }

crates/codegen/runtime/cargo/src/runtime/parse_error.rs

@@ -1,7 +1,10 @@
 use std::collections::BTreeSet;
+use std::error::Error;
+use std::fmt;
 
+use crate::diagnostic::{self, Diagnostic};
 use crate::kinds::TokenKind;
-use crate::text_index::{TextRange, TextRangeExtensions};
+use crate::text_index::TextRange;
 
 #[derive(Debug, PartialEq, Eq, Clone)]
 pub struct ParseError {
@@ -13,22 +16,6 @@ impl ParseError {
     pub fn text_range(&self) -> &TextRange {
         &self.text_range
     }
-
-    pub fn tokens_that_would_have_allowed_more_progress(&self) -> Vec<String> {
-        let tokens_that_would_have_allowed_more_progress = self
-            .tokens_that_would_have_allowed_more_progress
-            .iter()
-            .collect::<BTreeSet<_>>();
-
-        tokens_that_would_have_allowed_more_progress
-            .into_iter()
-            .map(TokenKind::to_string)
-            .collect()
-    }
-
-    pub fn to_error_report(&self, source_id: &str, source: &str, with_color: bool) -> String {
-        render_error_report(self, source_id, source, with_color)
-    }
 }
 
 impl ParseError {
@@ -43,52 +30,40 @@ impl ParseError {
     }
 }
 
-pub(crate) fn render_error_report(
-    error: &ParseError,
-    source_id: &str,
-    source: &str,
-    with_color: bool,
-) -> String {
-    use ariadne::{Color, Config, Label, Report, ReportKind, Source};
-
-    let kind = ReportKind::Error;
-    let color = if with_color { Color::Red } else { Color::Unset };
-
-    let tokens_that_would_have_allowed_more_progress =
-        error.tokens_that_would_have_allowed_more_progress();
-    let message = if tokens_that_would_have_allowed_more_progress.is_empty() {
-        "Expected end of file.".to_string()
-    } else {
-        format!(
-            "Expected {expectations}.",
-            expectations = tokens_that_would_have_allowed_more_progress.join(" or ")
-        )
-    };
-
-    if source.is_empty() {
-        return format!("{kind}: {message}\n   ─[{source_id}:0:0]");
+impl Error for ParseError {}
+impl fmt::Display for ParseError {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        if self.tokens_that_would_have_allowed_more_progress.is_empty() {
+            write!(f, "Expected end of file.")
+        } else {
+            let deduped = self
+                .tokens_that_would_have_allowed_more_progress
+                .iter()
+                .collect::<BTreeSet<_>>();
+
+            write!(f, "Expected ")?;
+
+            for kind in deduped.iter().take(deduped.len() - 1) {
+                write!(f, "{kind} or ")?;
+            }
+            let last = deduped.last().expect("we just checked that it's not empty");
+            write!(f, "{last}.")?;
+
+            Ok(())
+        }
     }
+}
 
-    let range = error.text_range.char();
-
-    let mut builder = Report::build(kind, source_id, range.start)
-        .with_config(Config::default().with_color(with_color))
-        .with_message(message);
-
-    builder.add_label(
-        Label::new((source_id, range))
-            .with_color(color)
-            .with_message("Error occurred here.".to_string()),
-    );
+impl Diagnostic for ParseError {
+    fn range(&self) -> TextRange {
+        self.text_range.clone()
+    }
 
-    let mut result = vec![];
-    builder
-        .finish()
-        .write((source_id, Source::from(&source)), &mut result)
-        .expect("Failed to write report");
+    fn severity(&self) -> diagnostic::Severity {
+        diagnostic::Severity::Error
+    }
 
-    return String::from_utf8(result)
-        .expect("Failed to convert report to utf8")
-        .trim()
-        .to_string();
+    fn message(&self) -> String {
+        ToString::to_string(&self)
+    }
 }

crates/solidity/outputs/cargo/slang_solidity/Cargo.toml

@@ -33,7 +33,9 @@ required-features = ["cli"]
 
 [features]
 default = ["cli"]
-cli = ["dep:anyhow", "dep:clap", "dep:serde_json"]
+cli = ["dep:anyhow", "dep:clap", "dep:serde_json", "__private_ariadne"]
+# This is meant to be used by the CLI or internally only.
+__private_ariadne = ["dep:ariadne"]
 
 [build-dependencies] # __REMOVE_THIS_LINE_DURING_CARGO_PUBLISH__
 anyhow = { workspace = true }                    # __REMOVE_THIS_LINE_DURING_CARGO_PUBLISH__
@@ -43,7 +45,7 @@ solidity_language = { workspace = true }         # __REMOVE_THIS_LINE_DURING_CAR
 
 [dependencies]
 anyhow = { workspace = true, optional = true }
-ariadne = { workspace = true }
+ariadne = { workspace = true, optional = true }
 clap = { workspace = true, optional = true }
 nom = { workspace = true }
 semver = { workspace = true }