report syntax errors as statix errors

- statix now reports errors also, not just warnings
- all diagnostics are available on stderr stream
- non-utf8 files are skipped, does not eject early

6 files changed, 89 insertions, 41 deletions

diff --git a/bin/src/config.rs b/bin/src/config.rs
index cbb1f66..ef3a29d 100644
--- a/bin/src/config.rs
+++ b/bin/src/config.rs
@@ -190,9 +190,12 @@ fn walk_with_ignores<P: AsRef<Path>>(
 fn vfs(files: Vec<PathBuf>) -> Result<ReadOnlyVfs, ConfigErr> {
     let mut vfs = ReadOnlyVfs::default();
     for file in files.iter() {
-        let _id = vfs.alloc_file_id(&file);
-        let data = fs::read_to_string(&file).map_err(ConfigErr::InvalidPath)?;
-        vfs.set_file_contents(&file, data.as_bytes());
+        if let Ok(data) = fs::read_to_string(&file) {
+            let _id = vfs.alloc_file_id(&file);
+            vfs.set_file_contents(&file, data.as_bytes());
+        } else {
+            println!("{} contains non-utf8 content", file.display());
+        };
     }
     Ok(vfs)
 }
diff --git a/bin/src/err.rs b/bin/src/err.rs
index 53c3222..4c16d69 100644
--- a/bin/src/err.rs
+++ b/bin/src/err.rs
@@ -1,7 +1,7 @@
-use std::{io, path::PathBuf};
+use std::io;
 
 use globset::ErrorKind;
-use rnix::parser::ParseError;
+// use rnix::parser::ParseError;
 use thiserror::Error;
 
 #[derive(Error, Debug)]
@@ -14,16 +14,16 @@ pub enum ConfigErr {
     InvalidPosition(String),
 }
 
-#[derive(Error, Debug)]
-pub enum LintErr {
-    #[error("[{0}] syntax error: {1}")]
-    Parse(PathBuf, ParseError),
-}
+// #[derive(Error, Debug)]
+// pub enum LintErr {
+//     #[error("[{0}] syntax error: {1}")]
+//     Parse(PathBuf, ParseError),
+// }
 
 #[derive(Error, Debug)]
 pub enum FixErr {
-    #[error("[{0}] syntax error: {1}")]
-    Parse(PathBuf, ParseError),
+    // #[error("[{0}] syntax error: {1}")]
+    // Parse(PathBuf, ParseError),
     #[error("path error: {0}")]
     InvalidPath(#[from] io::Error),
 }
@@ -42,8 +42,8 @@ pub enum SingleFixErr {
 
 #[derive(Error, Debug)]
 pub enum StatixErr {
-    #[error("linter error: {0}")]
-    Lint(#[from] LintErr),
+    // #[error("linter error: {0}")]
+    // Lint(#[from] LintErr),
     #[error("fixer error: {0}")]
     Fix(#[from] FixErr),
     #[error("single fix error: {0}")]
diff --git a/bin/src/lint.rs b/bin/src/lint.rs
index 65ae824..e889d31 100644
--- a/bin/src/lint.rs
+++ b/bin/src/lint.rs
@@ -1,5 +1,3 @@
-use crate::err::LintErr;
-
 use lib::{Report, LINTS};
 use rnix::WalkEvent;
 use vfs::{FileId, VfsEntry};
@@ -10,11 +8,16 @@ pub struct LintResult {
     pub reports: Vec<Report>,
 }
 
-pub fn lint(vfs_entry: VfsEntry) -> Result<LintResult, LintErr> {
+pub fn lint(vfs_entry: VfsEntry) -> LintResult {
+    let file_id = vfs_entry.file_id;
     let source = vfs_entry.contents;
-    let parsed = rnix::parse(source)
-        .as_result()
-        .map_err(|e| LintErr::Parse(vfs_entry.file_path.to_path_buf(), e))?;
+    let parsed = rnix::parse(source);
+
+    let error_reports = parsed
+        .errors()
+        .into_iter()
+        .map(|e| Report::from_parse_err(e));
+
     let reports = parsed
         .node()
         .preorder_with_tokens()
@@ -28,9 +31,8 @@ pub fn lint(vfs_entry: VfsEntry) -> Result<LintResult, LintErr> {
             _ => None,
         })
         .flatten()
+        .chain(error_reports)
         .collect();
-    Ok(LintResult {
-        file_id: vfs_entry.file_id,
-        reports,
-    })
+
+    LintResult { file_id, reports }
 }
diff --git a/bin/src/main.rs b/bin/src/main.rs
index c5d0626..90b79ce 100644
--- a/bin/src/main.rs
+++ b/bin/src/main.rs
@@ -20,17 +20,9 @@ fn _main() -> Result<(), StatixErr> {
     match opts.cmd {
         SubCommand::Check(check_config) => {
             let vfs = check_config.vfs()?;
-            let (lints, errors): (Vec<_>, Vec<_>) =
-                vfs.iter().map(lint::lint).partition(Result::is_ok);
-            let lint_results = lints.into_iter().map(Result::unwrap);
-            let errors = errors.into_iter().map(Result::unwrap_err);
-
-            let mut stdout = io::stdout();
-            lint_results.for_each(|r| {
-                stdout.write(&r, &vfs, check_config.format).unwrap();
-            });
-            errors.for_each(|e| {
-                eprintln!("{}", e);
+            let mut stderr = io::stderr();
+            vfs.iter().map(lint::lint).for_each(|r| {
+                stderr.write(&r, &vfs, check_config.format).unwrap();
             });
         }
         SubCommand::Fix(fix_config) => {
diff --git a/bin/src/traits.rs b/bin/src/traits.rs
index 465abe4..a8ec70f 100644
--- a/bin/src/traits.rs
+++ b/bin/src/traits.rs
@@ -9,6 +9,7 @@ use ariadne::{
     CharSet, Color, Config as CliConfig, Fmt, Label, LabelAttach, Report as CliReport,
     ReportKind as CliReportKind, Source,
 };
+use lib::Severity;
 use rnix::{TextRange, TextSize};
 use vfs::ReadOnlyVfs;
 
@@ -57,11 +58,16 @@ fn write_stderr<T: Write>(
             .map(|d| d.at.start().into())
             .min()
             .unwrap_or(0usize);
+        let report_kind = match report.severity {
+            Severity::Warn => CliReportKind::Warning,
+            Severity::Error => CliReportKind::Error,
+            Severity::Hint => CliReportKind::Advice,
+        };
         report
             .diagnostics
             .iter()
             .fold(
-                CliReport::build(CliReportKind::Warning, src_id, offset)
+                CliReport::build(report_kind, src_id, offset)
                     .with_config(
                         CliConfig::default()
                             .with_cross_gap(true)
@@ -103,7 +109,11 @@ fn write_errfmt<T: Write>(
                 filename = path.to_str().unwrap_or("<unknown>"),
                 linenumber = line,
                 columnnumber = col,
-                errortype = "W",
+                errortype = match report.severity {
+                    Severity::Warn => "W",
+                    Severity::Error => "E",
+                    Severity::Hint => "I", /* "info" message */
+                },
                 errornumber = report.code,
                 errormessage = diagnostic.message
             )?;
@@ -118,6 +128,7 @@ mod json {
 
     use std::io::{self, Write};
 
+    use lib::Severity;
     use rnix::TextRange;
     use serde::Serialize;
     use serde_json;
@@ -134,6 +145,7 @@ mod json {
     struct JsonReport<'μ> {
         note: &'static str,
         code: u32,
+        severity: &'μ Severity,
         diagnostics: Vec<JsonDiagnostic<'μ>>,
     }
 
@@ -192,6 +204,7 @@ mod json {
             .map(|r| {
                 let note = r.note;
                 let code = r.code;
+                let severity = &r.severity;
                 let diagnostics = r
                     .diagnostics
                     .iter()
@@ -207,6 +220,7 @@ mod json {
                 JsonReport {
                     note,
                     code,
+                    severity,
                     diagnostics,
                 }
             })
diff --git a/lib/src/lib.rs b/lib/src/lib.rs
index ec96f50..196cbf8 100644
--- a/lib/src/lib.rs
+++ b/lib/src/lib.rs
@@ -4,7 +4,7 @@ mod make;
 
 pub use lints::LINTS;
 
-use rnix::{SyntaxElement, SyntaxKind, TextRange};
+use rnix::{parser::ParseError, SyntaxElement, SyntaxKind, TextRange};
 use std::{convert::Into, default::Default};
 
 #[cfg(feature = "json-out")]
@@ -13,10 +13,18 @@ use serde::{
     Serialize,
 };
 
+#[derive(Debug)]
 #[cfg_attr(feature = "json-out", derive(Serialize))]
-pub struct Position {
-    line: usize,
-    column: usize,
+pub enum Severity {
+    Warn,
+    Error,
+    Hint,
+}
+
+impl Default for Severity {
+    fn default() -> Self {
+        Self::Warn
+    }
 }
 
 /// Report generated by a lint
@@ -27,6 +35,8 @@ pub struct Report {
     pub note: &'static str,
     /// An error code to uniquely identify this lint
     pub code: u32,
+    /// Report severity level
+    pub severity: Severity,
     /// Collection of diagnostics raised by this lint
     pub diagnostics: Vec<Diagnostic>,
 }
@@ -56,6 +66,11 @@ impl Report {
             .push(Diagnostic::suggest(at, message, suggestion));
         self
     }
+    /// Set severity level
+    pub fn severity(mut self, severity: Severity) -> Self {
+        self.severity = severity;
+        self
+    }
     /// A range that encompasses all the suggestions provided in this report
     pub fn total_suggestion_range(&self) -> Option<TextRange> {
         self.diagnostics
@@ -80,6 +95,28 @@ impl Report {
             d.apply(src);
         }
     }
+    /// Create a report out of a parse error
+    pub fn from_parse_err(err: ParseError) -> Self {
+        let at = match err {
+            ParseError::Unexpected(at) => at,
+            ParseError::UnexpectedExtra(at) => at,
+            ParseError::UnexpectedWanted(_, at, _) => at,
+            ParseError::UnexpectedDoubleBind(at) => at,
+            ParseError::UnexpectedEOF | ParseError::UnexpectedEOFWanted(_) => {
+                TextRange::empty(0u32.into())
+            }
+            _ => panic!("report a bug, pepper forgot to handle a parse error"),
+        };
+        let mut message = err.to_string();
+        message
+            .as_mut_str()
+            .get_mut(0..1)
+            .unwrap()
+            .make_ascii_uppercase();
+        Self::new("Syntax error", 0)
+            .diagnostic(at, message)
+            .severity(Severity::Error)
+    }
 }
 
 /// Mapping from a bytespan to an error message.