From 2aad8c9744e563b143e11360423ee8f54066d2f7 Mon Sep 17 00:00:00 2001
From: Gabriel Majeri <gabriel.majeri6@gmail.com>
Date: Tue, 9 Jun 2020 13:02:43 +0300
Subject: [PATCH] Fix parsing a line comment then EOF

---
 src/lexer.rs          |  3 ++-
 tests/parse_tokens.rs | 14 ++++++++++++++
 2 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/src/lexer.rs b/src/lexer.rs
index d7a3b92..9360b33 100644
--- a/src/lexer.rs
+++ b/src/lexer.rs
@@ -128,7 +128,7 @@ impl<'a, R: Read> Lexer<'a, R> {
     fn single_line_comment(&mut self) -> Result<(), ParserError>
     {
         loop {
-            if new_line_char!(self.skip_char()?) {
+            if self.eof()? || new_line_char!(self.skip_char()?) {
                 break;
             }
         }
@@ -872,6 +872,7 @@ impl<'a, R: Read> Lexer<'a, R> {
 
                 self.name_token(c)
             },
+            Err(ParserError::UnexpectedEOF) => Ok(Token::End),
             Err(e) => Err(e)
         }
     }
diff --git a/tests/parse_tokens.rs b/tests/parse_tokens.rs
index 7ea8251..263fcf8 100644
--- a/tests/parse_tokens.rs
+++ b/tests/parse_tokens.rs
@@ -91,3 +91,17 @@ fn char_with_hexseq() -> Result<(), ParserError> {
 fn char_with_hexseq_invalid() {
     assert!(read_all_tokens(r"'\x\' ").is_err());
 }
+
+#[test]
+fn empty() -> Result<(), ParserError> {
+    let tokens = read_all_tokens("")?;
+    assert!(tokens.is_empty());
+    Ok(())
+}
+
+#[test]
+fn comment_then_eof() -> Result<(), ParserError> {
+    let tokens = read_all_tokens("% only a comment")?;
+    assert_eq!(tokens, [Token::End]);
+    Ok(())
+}