regex: explicitly return an error for unsupported non-greedy repetitions

1 files changed, 20 insertions, 19 deletions

diff --git a/src/parse/regex/mod.rs b/src/parse/regex/mod.rs
index f35d3f2..72e11da 100644
--- a/src/parse/regex/mod.rs
+++ b/src/parse/regex/mod.rs
@@ -1,4 +1,4 @@
-use crate::parse::OtherHighlights;
+use crate::parse::{NotImplementedKind, OtherHighlights};
 
 use super::{Parse, ParseError, Result};
 
@@ -98,26 +98,27 @@ fn parse_rep(s: &mut super::Cursor<'_>) -> Result<Pattern> {
 
     let begin = s.loc();
 
-    match s.peek() {
-        b'*' => {
-            s.adv();
-            s.highlight_from(begin, OtherHighlights::RegexSymbol);
-            Ok(Pattern::Rep(Box::new(atom), 0, None))
-        }
-        b'+' => {
-            s.adv();
-            s.highlight_from(begin, OtherHighlights::RegexSymbol);
-            Ok(Pattern::Rep(Box::new(atom), 1, None))
-        }
-        b'?' => {
-            s.adv();
-            s.highlight_from(begin, OtherHighlights::RegexSymbol);
-            Ok(Pattern::Rep(Box::new(atom), 0, Some(1)))
+    let rep = match s.peek() {
+        b'*' => Some((0, None)),
+        b'+' => Some((1, None)),
+        b'?' => Some((0, Some(1))),
+        _ => None,
+    };
+
+    if let Some((min_rep, max_rep)) = rep {
+        s.adv();
+        s.highlight_from(begin, OtherHighlights::RegexSymbol);
+
+        if s.has() && s.peek() == b'?' {
+            return Err(ParseError::NotYetImplemented(
+                NotImplementedKind::NonGreedyRegexRepetition,
+            ));
         }
-        _ => Ok(atom),
-    }
 
-    // TODO: non-greedy
+        Ok(Pattern::Rep(Box::new(atom), min_rep, max_rep))
+    } else {
+        Ok(atom)
+    }
 }
 
 const SYMBOLS: &[u8] = b"{}[]()*+-?|.\\ ";