Improve some of the diagnostics

A few updates to diagnostic reports:
- In case of parse errors, tell the user that this might affect the
  results.
- Also in case of parse errors, if debug-logging is enabled, add the
  ERROR nodes to the output.
- Reword the error message to say "disallowed" instead of "non-ascii"
  characters.

README.md

@@ -12,16 +12,15 @@ Where `[FILES]...` is a list of files or directory to check.
 
 ```console
 $ unicop example-files/homoglyph.js example-files/invisible.js
-  × found non-ascii character LATIN LETTER RETROFLEX CLICK in identifier
+  × found disallowed character LATIN LETTER RETROFLEX CLICK in identifier
    ╭─[example-files/homoglyph.js:4:18]
  3 │ function isUserAdmin(user) {
  4 │    if(environmentǃ=ENV_PROD){
    ·                  ┬
    ·                  ╰── LATIN LETTER RETROFLEX CLICK
  5 │        // bypass authZ checks in DEV
    ╰────
-
-  × found non-ascii character HANGUL JUNGSEONG FILLER in
+  × found disallowed character HANGUL JUNGSEONG FILLER in
   │ shorthand_property_identifier_pattern
    ╭─[example-files/invisible.js:2:20]
  1 │ app.get('/network_health', async (req, res) => {
@@ -30,8 +29,7 @@ $ unicop example-files/homoglyph.js example-files/invisible.js
    ·                    ╰── HANGUL JUNGSEONG FILLER
  3 │    const checkCommands = [
    ╰────
-
-  × found non-ascii character HANGUL JUNGSEONG FILLER in identifier
+  × found disallowed character HANGUL JUNGSEONG FILLER in identifier
    ╭─[example-files/invisible.js:5:38]
  4 │        'ping -c 1 google.com',
  5 │        'curl -s http://example.com/',ᅠ
@@ -40,7 +38,6 @@ $ unicop example-files/homoglyph.js example-files/invisible.js
  6 │    ];
    ╰────
 
-
 ```
 
 ## Contributing to unicop

src/main.rs

@@ -153,11 +153,27 @@ fn check_file(dispatcher: &RuleDispatcher, path: &Path) {
         .expect("Error loading grammar");
     let tree = parser.parse(&src, None).unwrap();
     if tree.root_node().has_error() {
-        println!(
-            "{:?}",
-            miette!(severity = Severity::Warning, "{}: parse error", filename)
-                .with_source_code(named_source.clone())
-        );
+        let mut labels = Vec::new();
+        if log::log_enabled!(log::Level::Debug) {
+            let query = tree_sitter::Query::new(&lang.grammar(), "(ERROR) @error").unwrap();
+            let mut cursor = tree_sitter::QueryCursor::new();
+            for (r#match, _) in cursor.captures(&query, tree.root_node(), src.as_bytes()) {
+                for capture in r#match.captures {
+                    labels.push(LabeledSpan::at(
+                        capture.node.start_byte()..capture.node.end_byte(),
+                        "Error",
+                    ));
+                }
+            }
+        }
+        let report = miette!(
+            severity = Severity::Warning,
+            labels = labels,
+            "{}: parse error, results might be incorrect",
+            filename
+        )
+        .with_source_code(named_source.clone());
+        print!("{:?}", report);
     }
     for (off, ch) in src.char_indices() {
         let node = tree
@@ -176,12 +192,12 @@ fn check_file(dispatcher: &RuleDispatcher, path: &Path) {
                 off..off + ch.len_utf8(),
                 chname.to_string()
             )],
-            "found non-ascii character {} in {}",
+            "found disallowed character {} in {}",
             chname,
             node.kind()
         )
         .with_source_code(named_source.clone());
-        println!("{:?}", report);
+        print!("{:?}", report);
     }
 }