From 623a78dbf9acfc4ce5de441d1fb99098de70fdc2 Mon Sep 17 00:00:00 2001
From: Dennis Zhuang <killme2008@gmail.com>
Date: Sun, 19 Jun 2022 22:34:34 +0800
Subject: [PATCH] fix panic when parsing invalid decimal, close #3796

---
 extra_tests/snippets/syntax_decimal.py | 6 ++++++
 parser/src/lexer.rs                    | 5 ++++-
 2 files changed, 10 insertions(+), 1 deletion(-)
 create mode 100644 extra_tests/snippets/syntax_decimal.py

diff --git a/extra_tests/snippets/syntax_decimal.py b/extra_tests/snippets/syntax_decimal.py
new file mode 100644
index 000000000..d7320f2ca
--- /dev/null
+++ b/extra_tests/snippets/syntax_decimal.py
@@ -0,0 +1,6 @@
+try:
+    eval("0.E")
+except SyntaxError:
+   pass
+else:
+  assert False
diff --git a/parser/src/lexer.rs b/parser/src/lexer.rs
index b3fda9264..ac46b10bc 100644
--- a/parser/src/lexer.rs
+++ b/parser/src/lexer.rs
@@ -300,7 +300,10 @@ where
                 value_text.push_str(&self.radix_run(10));
             }
 
-            let value = f64::from_str(&value_text).unwrap();
+            let value = f64::from_str(&value_text).map_err(|_| LexicalError {
+                error: LexicalErrorType::OtherError("Invalid decimal literal".to_owned()),
+                location: self.get_pos(),
+            })?;
             // Parse trailing 'j':
             if self.chr0 == Some('j') || self.chr0 == Some('J') {
                 self.next_char();