From 8d4aca42b40f713230a08e4e9618fb76187ff9dd Mon Sep 17 00:00:00 2001
From: Wleeaf <179125857+wleeaf@users.noreply.github.com>
Date: Sun, 25 Oct 2026 14:23:23 +0000
Subject: [PATCH] fix: don't treat backslashes in comments as escapes

The parser handled escape sequences in every token, including comments.
In java.util.Properties a backslash has no special meaning in a comment
line, and a comment line can't be continued. Here a comment with a
Windows path made loading fail ("# C:\users" is read as a malformed
\uXXXX escape), and a comment ending with a backslash swallowed the
next line, so the property on it was lost:

    # temp dir: C:\temp\
    alpha=1

Comments are now read as they are, up to the end of the line.
---
 .../org/codejive/properties/PropertiesParser.java |  3 ++-
 .../org/codejive/properties/TestProperties.java   |  8 ++++++++
 .../codejive/properties/TestPropertiesParser.java | 15 +++++++++++++++
 3 files changed, 25 insertions(+), 1 deletion(-)

diff --git a/src/main/java/org/codejive/properties/PropertiesParser.java b/src/main/java/org/codejive/properties/PropertiesParser.java
index 8a37551..5bfa3e0 100644
--- a/src/main/java/org/codejive/properties/PropertiesParser.java
+++ b/src/main/java/org/codejive/properties/PropertiesParser.java
@@ -269,7 +269,8 @@ private int readChar() throws IOException {
 
     private void addChar(int ch) throws IOException {
         str.append((char) ch);
-        if (ch == '\\') {
+        // Comments have no escapes or line continuations
+        if (ch == '\\' && state != Type.COMMENT) {
             hasEscapes = true;
             int ch2 = readChar();
             str.append((char) ch2);
diff --git a/src/test/java/org/codejive/properties/TestProperties.java b/src/test/java/org/codejive/properties/TestProperties.java
index 989d325..b53273a 100644
--- a/src/test/java/org/codejive/properties/TestProperties.java
+++ b/src/test/java/org/codejive/properties/TestProperties.java
@@ -822,6 +822,14 @@ void testPutAtInvalidPosition() throws IOException {
         assertThat(p).containsEntry("middle", "3");
     }
 
+    @Test
+    void testCommentEndingWithBackslash() throws IOException {
+        Properties p =
+                Properties.loadProperties(new StringReader("# temp dir: C:\\temp\\\nalpha=1\n"));
+
+        assertThat(p).containsEntry("alpha", "1");
+    }
+
     @Test
     void testPutNewTest2() throws IOException, URISyntaxException {
         Path f = getResource("/test2.properties");
diff --git a/src/test/java/org/codejive/properties/TestPropertiesParser.java b/src/test/java/org/codejive/properties/TestPropertiesParser.java
index f967642..3214ff3 100644
--- a/src/test/java/org/codejive/properties/TestPropertiesParser.java
+++ b/src/test/java/org/codejive/properties/TestPropertiesParser.java
@@ -108,6 +108,21 @@ void testStringify() throws IOException {
         assertThat(props2).isEqualTo(props);
     }
 
+    @Test
+    void testBackslashesInComment() throws IOException {
+        List<Token> tokens =
+                PropertiesParser.tokens(new StringReader("# C:\\users\\\nfoo=bar"))
+                        .collect(Collectors.toList());
+
+        assertThat(tokens)
+                .containsExactly(
+                        new Token(Type.COMMENT, "# C:\\users\\"),
+                        new Token(Type.WHITESPACE, "\n"),
+                        new Token(Type.KEY, "foo"),
+                        new Token(Type.SEPARATOR, "="),
+                        new Token(Type.VALUE, "bar"));
+    }
+
     @Test
     void testEmptySeparatorAndValueAtEof() throws IOException {
         List<Token> tokens =