From dbc3ea0a33dd6aecca66d2d8083b516f366d1452 Mon Sep 17 00:00:00 2001
From: Luke <luke.k.xu@hotmail.com>
Date: Tue, 1 Jul 2025 17:10:11 +0800
Subject: [PATCH] =?UTF-8?q?feat:=20NewlineTokenScanner=20=E9=87=8D?=
 =?UTF-8?q?=E6=9E=84=E4=B8=BA=E7=8A=B6=E6=80=81=E6=9C=BA?=
MIME-Version: 1.0
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---
 .../lexer/scanners/NewlineTokenScanner.java   | 27 ++++++++++++++++---
 1 file changed, 23 insertions(+), 4 deletions(-)

diff --git a/src/main/java/org/jcnc/snow/compiler/lexer/scanners/NewlineTokenScanner.java b/src/main/java/org/jcnc/snow/compiler/lexer/scanners/NewlineTokenScanner.java
index daea57c..0f63e70 100644
--- a/src/main/java/org/jcnc/snow/compiler/lexer/scanners/NewlineTokenScanner.java
+++ b/src/main/java/org/jcnc/snow/compiler/lexer/scanners/NewlineTokenScanner.java
@@ -7,10 +7,19 @@ import org.jcnc.snow.compiler.lexer.token.TokenType;
 /**
  * 换行符扫描器：将源代码中的换行符（\n）识别为 {@code NEWLINE} 类型的 Token。
  * <p>
- * 通常用于记录行的分界，辅助语法分析阶段进行行敏感的判断或保持结构清晰。
+ * 用于记录行的分界，辅助语法分析阶段进行行敏感的判断或保持结构清晰。
  */
 public class NewlineTokenScanner extends AbstractTokenScanner {
 
+    // 定义状态枚举
+    private enum State {
+        INITIAL,
+        NEWLINE
+    }
+
+    // 当前状态
+    private State currentState = State.INITIAL;
+
     /**
      * 判断是否可以处理当前位置的字符。
      * <p>当字符为换行符（\n）时返回 true。</p>
@@ -21,7 +30,8 @@ public class NewlineTokenScanner extends AbstractTokenScanner {
      */
     @Override
     public boolean canHandle(char c, LexerContext ctx) {
-        return c == '\n';
+        // 只有当处于 INITIAL 状态，并且遇到换行符时，才可以处理
+        return currentState == State.INITIAL && c == '\n';
     }
 
     /**
@@ -35,7 +45,16 @@ public class NewlineTokenScanner extends AbstractTokenScanner {
      */
     @Override
     protected Token scanToken(LexerContext ctx, int line, int col) {
+        // 状态转换为 NEWLINE
+        currentState = State.NEWLINE;
+
+        // 执行换行符扫描，生成 token
         ctx.advance();
-        return new Token(TokenType.NEWLINE, "\n", line, col);
+        Token newlineToken = new Token(TokenType.NEWLINE, "\n", line, col);
+
+        // 扫描完成后，恢复状态为 INITIAL
+        currentState = State.INITIAL;
+
+        return newlineToken;
     }
-}
\ No newline at end of file
+}