From b3f7932d0b13bcb37d44f7f5dae2fc33b9d50f59 Mon Sep 17 00:00:00 2001
From: jsxs <jazndj2@gmail.com>
Date: Thu, 5 Jun 2025 14:30:01 +0900
Subject: [PATCH 01/12] fix: accept \r in unquoted fields when row_sep excludes
 \r

Fixes #60
---
 lib/csv/parser.rb                  |  5 ++-
 test/csv/parse/test_general.rb     | 33 +++++++--------
 test/csv/parse/test_invalid.rb     | 11 +++--
 test/csv/parse/test_unquoted_cr.rb | 68 ++++++++++++++++++++++++++++++
 4 files changed, 92 insertions(+), 25 deletions(-)
 create mode 100644 test/csv/parse/test_unquoted_cr.rb

diff --git a/lib/csv/parser.rb b/lib/csv/parser.rb
index 4a74e40d..a7dd9632 100644
--- a/lib/csv/parser.rb
+++ b/lib/csv/parser.rb
@@ -675,7 +675,10 @@ def prepare_quoted
     def prepare_unquoted
       return if @quote_character.nil?
 
-      no_unquoted_values = "\r\n".encode(@encoding)
+      # Only exclude characters that are actually part of the row separator
+      # instead of hardcoding "\r\n"
+      row_separator_chars = @row_separator.chars.map { |c| Regexp.escape(c) }.join
+      no_unquoted_values = row_separator_chars.encode(@encoding)
       no_unquoted_values << @escaped_first_column_separator
       unless @liberal_parsing
         no_unquoted_values << @escaped_quote_character
diff --git a/test/csv/parse/test_general.rb b/test/csv/parse/test_general.rb
index 7ec0994e..3dec620e 100644
--- a/test/csv/parse/test_general.rb
+++ b/test/csv/parse/test_general.rb
@@ -139,27 +139,24 @@ def test_non_regex_edge_cases
   end
 
   def test_malformed_csv_cr_first_line
-    error = assert_raise(CSV::MalformedCSVError) do
-      CSV.parse_line("1,2\r,3", row_sep: "\n")
-    end
-    assert_equal("Unquoted fields do not allow new line <\"\\r\"> in line 1.",
-                 error.message)
+    # With the fix for accepting \r without quote when row separator doesn't include \r,
+    # this should now parse successfully when row_sep is "\n"
+    result = CSV.parse_line("1,2\r,3", row_sep: "\n")
+    assert_equal(["1", "2\r", "3"], result)
   end
 
   def test_malformed_csv_cr_middle_line
-    csv = <<-CSV
-line,1,abc
-line,2,"def\nghi"
-
-line,4,some\rjunk
-line,5,jkl
-    CSV
-
-    error = assert_raise(CSV::MalformedCSVError) do
-      CSV.parse(csv)
-    end
-    assert_equal("Unquoted fields do not allow new line <\"\\r\"> in line 4.",
-                 error.message)
+    # With the fix for accepting \r without quote when row separator doesn't include \r,
+    # this should now parse successfully (default row_sep is "\n")
+    csv = "line,1,abc\nline,2,\"def\nghi\"\nline,4,some\rjunk\nline,5,jkl\n"
+    result = CSV.parse(csv)
+    expected = [
+      ["line", "1", "abc"],
+      ["line", "2", "def\nghi"],
+      ["line", "4", "some\rjunk"],
+      ["line", "5", "jkl"]
+    ]
+    assert_equal(expected, result)
   end
 
   def test_malformed_csv_unclosed_quote
diff --git a/test/csv/parse/test_invalid.rb b/test/csv/parse/test_invalid.rb
index ddb59e2b..8e5d1b08 100644
--- a/test/csv/parse/test_invalid.rb
+++ b/test/csv/parse/test_invalid.rb
@@ -5,12 +5,11 @@
 
 class TestCSVParseInvalid < Test::Unit::TestCase
   def test_no_column_mixed_new_lines
-    error = assert_raise(CSV::MalformedCSVError) do
-      CSV.parse("\n" +
-                "\r")
-    end
-    assert_equal("New line must be <\"\\n\"> not <\"\\r\"> in line 2.",
-                 error.message)
+    # With the fix for accepting \r without quote when row separator doesn't include \r,
+    # this should now parse successfully (default row_sep is "\n")
+    result = CSV.parse("\n" + "\r")
+    # This should parse as an empty first row and a second row with just "\r"
+    assert_equal([[], ["\r"]], result)
   end
 
   def test_ignore_invalid_line
diff --git a/test/csv/parse/test_unquoted_cr.rb b/test/csv/parse/test_unquoted_cr.rb
new file mode 100644
index 00000000..4381de0f
--- /dev/null
+++ b/test/csv/parse/test_unquoted_cr.rb
@@ -0,0 +1,68 @@
+# -*- coding: utf-8 -*-
+# frozen_string_literal: false
+
+require_relative "../helper"
+
+class TestCSVParseUnquotedCR < Test::Unit::TestCase
+  extend DifferentOFS
+
+  def test_accept_cr_in_unquoted_field_when_row_separator_is_lf_only
+    # When row separator is just \n, \r should be allowed in unquoted fields
+    data = "field1,field\rwith\rcr,field3\nrow2,data,here\n"
+    expected = [
+      ["field1", "field\rwith\rcr", "field3"],
+      ["row2", "data", "here"]
+    ]
+    assert_equal(expected, CSV.parse(data, row_sep: "\n"))
+  end
+
+  def test_accept_cr_in_unquoted_field_when_row_separator_is_custom
+    # When row separator is custom (like "|"), \r should be allowed in unquoted fields
+    data = "field1,field\rwith\rcr,field3|row2,data,here|"
+    expected = [
+      ["field1", "field\rwith\rcr", "field3"],
+      ["row2", "data", "here"]
+    ]
+    assert_equal(expected, CSV.parse(data, row_sep: "|"))
+  end
+
+  def test_reject_cr_when_row_separator_includes_cr
+    # When row separator includes \r (like \r\n), \r should still be rejected in unquoted fields
+    data = "field1,field2,field3\r\nrow2,data,here\r\n"
+    expected = [
+      ["field1", "field2", "field3"],
+      ["row2", "data", "here"]
+    ]
+    assert_equal(expected, CSV.parse(data, row_sep: "\r\n"))
+  end
+
+  def test_reject_cr_when_row_separator_is_cr_only
+    # When row separator is just \r, \r should be rejected in unquoted fields
+    data = "field1,field2,field3\rrow2,data,here\r"
+    expected = [
+      ["field1", "field2", "field3"],
+      ["row2", "data", "here"]
+    ]
+    assert_equal(expected, CSV.parse(data, row_sep: "\r"))
+  end
+
+  def test_liberal_parsing_with_custom_row_separator
+    # Test liberal parsing mode with custom row separator
+    data = "field1,field\rwith\rcr,field3|row2,data,here|"
+    expected = [
+      ["field1", "field\rwith\rcr", "field3"],
+      ["row2", "data", "here"]
+    ]
+    assert_equal(expected, CSV.parse(data, row_sep: "|", liberal_parsing: true))
+  end
+
+  def test_quoted_fields_with_cr_and_custom_row_separator
+    # Quoted fields should always allow \r regardless of row separator
+    data = "field1,\"field\rwith\rcr\",field3|row2,data,here|"
+    expected = [
+      ["field1", "field\rwith\rcr", "field3"],
+      ["row2", "data", "here"]
+    ]
+    assert_equal(expected, CSV.parse(data, row_sep: "|"))
+  end
+end 

From 440c545fada134c6a9a2d8f35ca3125fe616ea3b Mon Sep 17 00:00:00 2001
From: jsxs <jazndj2@gmail.com>
Date: Thu, 5 Jun 2025 14:30:01 +0900
Subject: [PATCH 02/12] fix: accept \r in unquoted fields when row_sep excludes
 \r - simplified implementation based on review feedback

---
 .gitignore                         |  1 +
 lib/csv/parser.rb                  |  4 +-
 test/csv/parse/test_general.rb     | 33 +++++++--------
 test/csv/parse/test_invalid.rb     | 11 +++--
 test/csv/parse/test_unquoted_cr.rb | 68 ++++++++++++++++++++++++++++++
 5 files changed, 92 insertions(+), 25 deletions(-)
 create mode 100644 test/csv/parse/test_unquoted_cr.rb

diff --git a/.gitignore b/.gitignore
index a57ca09e..45a01580 100644
--- a/.gitignore
+++ b/.gitignore
@@ -5,3 +5,4 @@
 /pkg/
 /spec/reports/
 /tmp/
+/vendor
diff --git a/lib/csv/parser.rb b/lib/csv/parser.rb
index 4a74e40d..f3d896eb 100644
--- a/lib/csv/parser.rb
+++ b/lib/csv/parser.rb
@@ -675,7 +675,9 @@ def prepare_quoted
     def prepare_unquoted
       return if @quote_character.nil?
 
-      no_unquoted_values = "\r\n".encode(@encoding)
+              # Only exclude characters that are actually part of the row separator
+        # instead of hardcoding "\r\n"
+        no_unquoted_values = Regexp.escape(@row_separator).encode(@encoding)
       no_unquoted_values << @escaped_first_column_separator
       unless @liberal_parsing
         no_unquoted_values << @escaped_quote_character
diff --git a/test/csv/parse/test_general.rb b/test/csv/parse/test_general.rb
index 7ec0994e..3dec620e 100644
--- a/test/csv/parse/test_general.rb
+++ b/test/csv/parse/test_general.rb
@@ -139,27 +139,24 @@ def test_non_regex_edge_cases
   end
 
   def test_malformed_csv_cr_first_line
-    error = assert_raise(CSV::MalformedCSVError) do
-      CSV.parse_line("1,2\r,3", row_sep: "\n")
-    end
-    assert_equal("Unquoted fields do not allow new line <\"\\r\"> in line 1.",
-                 error.message)
+    # With the fix for accepting \r without quote when row separator doesn't include \r,
+    # this should now parse successfully when row_sep is "\n"
+    result = CSV.parse_line("1,2\r,3", row_sep: "\n")
+    assert_equal(["1", "2\r", "3"], result)
   end
 
   def test_malformed_csv_cr_middle_line
-    csv = <<-CSV
-line,1,abc
-line,2,"def\nghi"
-
-line,4,some\rjunk
-line,5,jkl
-    CSV
-
-    error = assert_raise(CSV::MalformedCSVError) do
-      CSV.parse(csv)
-    end
-    assert_equal("Unquoted fields do not allow new line <\"\\r\"> in line 4.",
-                 error.message)
+    # With the fix for accepting \r without quote when row separator doesn't include \r,
+    # this should now parse successfully (default row_sep is "\n")
+    csv = "line,1,abc\nline,2,\"def\nghi\"\nline,4,some\rjunk\nline,5,jkl\n"
+    result = CSV.parse(csv)
+    expected = [
+      ["line", "1", "abc"],
+      ["line", "2", "def\nghi"],
+      ["line", "4", "some\rjunk"],
+      ["line", "5", "jkl"]
+    ]
+    assert_equal(expected, result)
   end
 
   def test_malformed_csv_unclosed_quote
diff --git a/test/csv/parse/test_invalid.rb b/test/csv/parse/test_invalid.rb
index ddb59e2b..8e5d1b08 100644
--- a/test/csv/parse/test_invalid.rb
+++ b/test/csv/parse/test_invalid.rb
@@ -5,12 +5,11 @@
 
 class TestCSVParseInvalid < Test::Unit::TestCase
   def test_no_column_mixed_new_lines
-    error = assert_raise(CSV::MalformedCSVError) do
-      CSV.parse("\n" +
-                "\r")
-    end
-    assert_equal("New line must be <\"\\n\"> not <\"\\r\"> in line 2.",
-                 error.message)
+    # With the fix for accepting \r without quote when row separator doesn't include \r,
+    # this should now parse successfully (default row_sep is "\n")
+    result = CSV.parse("\n" + "\r")
+    # This should parse as an empty first row and a second row with just "\r"
+    assert_equal([[], ["\r"]], result)
   end
 
   def test_ignore_invalid_line
diff --git a/test/csv/parse/test_unquoted_cr.rb b/test/csv/parse/test_unquoted_cr.rb
new file mode 100644
index 00000000..4381de0f
--- /dev/null
+++ b/test/csv/parse/test_unquoted_cr.rb
@@ -0,0 +1,68 @@
+# -*- coding: utf-8 -*-
+# frozen_string_literal: false
+
+require_relative "../helper"
+
+class TestCSVParseUnquotedCR < Test::Unit::TestCase
+  extend DifferentOFS
+
+  def test_accept_cr_in_unquoted_field_when_row_separator_is_lf_only
+    # When row separator is just \n, \r should be allowed in unquoted fields
+    data = "field1,field\rwith\rcr,field3\nrow2,data,here\n"
+    expected = [
+      ["field1", "field\rwith\rcr", "field3"],
+      ["row2", "data", "here"]
+    ]
+    assert_equal(expected, CSV.parse(data, row_sep: "\n"))
+  end
+
+  def test_accept_cr_in_unquoted_field_when_row_separator_is_custom
+    # When row separator is custom (like "|"), \r should be allowed in unquoted fields
+    data = "field1,field\rwith\rcr,field3|row2,data,here|"
+    expected = [
+      ["field1", "field\rwith\rcr", "field3"],
+      ["row2", "data", "here"]
+    ]
+    assert_equal(expected, CSV.parse(data, row_sep: "|"))
+  end
+
+  def test_reject_cr_when_row_separator_includes_cr
+    # When row separator includes \r (like \r\n), \r should still be rejected in unquoted fields
+    data = "field1,field2,field3\r\nrow2,data,here\r\n"
+    expected = [
+      ["field1", "field2", "field3"],
+      ["row2", "data", "here"]
+    ]
+    assert_equal(expected, CSV.parse(data, row_sep: "\r\n"))
+  end
+
+  def test_reject_cr_when_row_separator_is_cr_only
+    # When row separator is just \r, \r should be rejected in unquoted fields
+    data = "field1,field2,field3\rrow2,data,here\r"
+    expected = [
+      ["field1", "field2", "field3"],
+      ["row2", "data", "here"]
+    ]
+    assert_equal(expected, CSV.parse(data, row_sep: "\r"))
+  end
+
+  def test_liberal_parsing_with_custom_row_separator
+    # Test liberal parsing mode with custom row separator
+    data = "field1,field\rwith\rcr,field3|row2,data,here|"
+    expected = [
+      ["field1", "field\rwith\rcr", "field3"],
+      ["row2", "data", "here"]
+    ]
+    assert_equal(expected, CSV.parse(data, row_sep: "|", liberal_parsing: true))
+  end
+
+  def test_quoted_fields_with_cr_and_custom_row_separator
+    # Quoted fields should always allow \r regardless of row separator
+    data = "field1,\"field\rwith\rcr\",field3|row2,data,here|"
+    expected = [
+      ["field1", "field\rwith\rcr", "field3"],
+      ["row2", "data", "here"]
+    ]
+    assert_equal(expected, CSV.parse(data, row_sep: "|"))
+  end
+end 

From 5b8f693eeaf9c7889a4ef18bf2428b4f200121b1 Mon Sep 17 00:00:00 2001
From: jsxs <jazndj2@gmail.com>
Date: Thu, 5 Jun 2025 16:08:32 +0900
Subject: [PATCH 03/12] Update .gitignore

---
 .gitignore | 1 -
 1 file changed, 1 deletion(-)

diff --git a/.gitignore b/.gitignore
index 45a01580..a57ca09e 100644
--- a/.gitignore
+++ b/.gitignore
@@ -5,4 +5,3 @@
 /pkg/
 /spec/reports/
 /tmp/
-/vendor

From c237450f70ef1644a8ae99c6f0605c6a3830585e Mon Sep 17 00:00:00 2001
From: jsxs <jazndj2@gmail.com>
Date: Thu, 5 Jun 2025 16:34:38 +0900
Subject: [PATCH 04/12] style: fix indentation in prepare_unquoted method

---
 lib/csv/parser.rb | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/lib/csv/parser.rb b/lib/csv/parser.rb
index f3d896eb..7dbdcb59 100644
--- a/lib/csv/parser.rb
+++ b/lib/csv/parser.rb
@@ -675,9 +675,9 @@ def prepare_quoted
     def prepare_unquoted
       return if @quote_character.nil?
 
-              # Only exclude characters that are actually part of the row separator
-        # instead of hardcoding "\r\n"
-        no_unquoted_values = Regexp.escape(@row_separator).encode(@encoding)
+      # Only exclude characters that are actually part of the row separator
+      # instead of hardcoding "\r\n"
+      no_unquoted_values = Regexp.escape(@row_separator).encode(@encoding)
       no_unquoted_values << @escaped_first_column_separator
       unless @liberal_parsing
         no_unquoted_values << @escaped_quote_character

From dd88061410ef28f0fbe9a94fa4559a4687e30b01 Mon Sep 17 00:00:00 2001
From: jsxs <jazndj2@gmail.com>
Date: Thu, 5 Jun 2025 17:22:51 +0900
Subject: [PATCH 05/12] reviewers' feedback

---
 lib/csv/parser.rb                  |  3 ++-
 test/csv/parse/test_general.rb     | 13 +++++++------
 test/csv/parse/test_invalid.rb     |  9 +--------
 test/csv/parse/test_unquoted_cr.rb | 24 ++++++++++++------------
 4 files changed, 22 insertions(+), 27 deletions(-)

diff --git a/lib/csv/parser.rb b/lib/csv/parser.rb
index 7dbdcb59..a7dd9632 100644
--- a/lib/csv/parser.rb
+++ b/lib/csv/parser.rb
@@ -677,7 +677,8 @@ def prepare_unquoted
 
       # Only exclude characters that are actually part of the row separator
       # instead of hardcoding "\r\n"
-      no_unquoted_values = Regexp.escape(@row_separator).encode(@encoding)
+      row_separator_chars = @row_separator.chars.map { |c| Regexp.escape(c) }.join
+      no_unquoted_values = row_separator_chars.encode(@encoding)
       no_unquoted_values << @escaped_first_column_separator
       unless @liberal_parsing
         no_unquoted_values << @escaped_quote_character
diff --git a/test/csv/parse/test_general.rb b/test/csv/parse/test_general.rb
index 3dec620e..e6f43e6c 100644
--- a/test/csv/parse/test_general.rb
+++ b/test/csv/parse/test_general.rb
@@ -138,16 +138,12 @@ def test_non_regex_edge_cases
     end
   end
 
-  def test_malformed_csv_cr_first_line
-    # With the fix for accepting \r without quote when row separator doesn't include \r,
-    # this should now parse successfully when row_sep is "\n"
+  def test_unquoted_cr_with_lf_row_separator
     result = CSV.parse_line("1,2\r,3", row_sep: "\n")
     assert_equal(["1", "2\r", "3"], result)
   end
 
-  def test_malformed_csv_cr_middle_line
-    # With the fix for accepting \r without quote when row separator doesn't include \r,
-    # this should now parse successfully (default row_sep is "\n")
+  def test_unquoted_cr_in_middle_line
     csv = "line,1,abc\nline,2,\"def\nghi\"\nline,4,some\rjunk\nline,5,jkl\n"
     result = CSV.parse(csv)
     expected = [
@@ -159,6 +155,11 @@ def test_malformed_csv_cr_middle_line
     assert_equal(expected, result)
   end
 
+  def test_empty_rows_with_cr
+    result = CSV.parse("\n" + "\r")
+    assert_equal([[], ["\r"]], result)
+  end
+
   def test_malformed_csv_unclosed_quote
     error = assert_raise(CSV::MalformedCSVError) do
       CSV.parse_line('1,2,"3...')
diff --git a/test/csv/parse/test_invalid.rb b/test/csv/parse/test_invalid.rb
index 8e5d1b08..11e7a977 100644
--- a/test/csv/parse/test_invalid.rb
+++ b/test/csv/parse/test_invalid.rb
@@ -1,16 +1,9 @@
-# -*- coding: utf-8 -*-
 # frozen_string_literal: false
 
 require_relative "../helper"
 
 class TestCSVParseInvalid < Test::Unit::TestCase
-  def test_no_column_mixed_new_lines
-    # With the fix for accepting \r without quote when row separator doesn't include \r,
-    # this should now parse successfully (default row_sep is "\n")
-    result = CSV.parse("\n" + "\r")
-    # This should parse as an empty first row and a second row with just "\r"
-    assert_equal([[], ["\r"]], result)
-  end
+
 
   def test_ignore_invalid_line
     csv = CSV.new(<<-CSV, headers: true, return_headers: true)
diff --git a/test/csv/parse/test_unquoted_cr.rb b/test/csv/parse/test_unquoted_cr.rb
index 4381de0f..fb353eb5 100644
--- a/test/csv/parse/test_unquoted_cr.rb
+++ b/test/csv/parse/test_unquoted_cr.rb
@@ -1,4 +1,3 @@
-# -*- coding: utf-8 -*-
 # frozen_string_literal: false
 
 require_relative "../helper"
@@ -6,8 +5,7 @@
 class TestCSVParseUnquotedCR < Test::Unit::TestCase
   extend DifferentOFS
 
-  def test_accept_cr_in_unquoted_field_when_row_separator_is_lf_only
-    # When row separator is just \n, \r should be allowed in unquoted fields
+  def test_unquoted_cr_with_lf_row_separator
     data = "field1,field\rwith\rcr,field3\nrow2,data,here\n"
     expected = [
       ["field1", "field\rwith\rcr", "field3"],
@@ -16,8 +14,7 @@ def test_accept_cr_in_unquoted_field_when_row_separator_is_lf_only
     assert_equal(expected, CSV.parse(data, row_sep: "\n"))
   end
 
-  def test_accept_cr_in_unquoted_field_when_row_separator_is_custom
-    # When row separator is custom (like "|"), \r should be allowed in unquoted fields
+  def test_unquoted_cr_with_custom_row_separator
     data = "field1,field\rwith\rcr,field3|row2,data,here|"
     expected = [
       ["field1", "field\rwith\rcr", "field3"],
@@ -26,8 +23,7 @@ def test_accept_cr_in_unquoted_field_when_row_separator_is_custom
     assert_equal(expected, CSV.parse(data, row_sep: "|"))
   end
 
-  def test_reject_cr_when_row_separator_includes_cr
-    # When row separator includes \r (like \r\n), \r should still be rejected in unquoted fields
+  def test_unquoted_cr_with_crlf_row_separator
     data = "field1,field2,field3\r\nrow2,data,here\r\n"
     expected = [
       ["field1", "field2", "field3"],
@@ -36,8 +32,14 @@ def test_reject_cr_when_row_separator_includes_cr
     assert_equal(expected, CSV.parse(data, row_sep: "\r\n"))
   end
 
-  def test_reject_cr_when_row_separator_is_cr_only
-    # When row separator is just \r, \r should be rejected in unquoted fields
+  def test_unquoted_cr_rejected_when_included_in_row_separator
+    data = "field1,field\r2,field3\r\nrow2,data,here\r\n"
+    assert_raise(CSV::MalformedCSVError) do
+      CSV.parse(data, row_sep: "\r\n")
+    end
+  end
+
+  def test_unquoted_cr_with_cr_row_separator
     data = "field1,field2,field3\rrow2,data,here\r"
     expected = [
       ["field1", "field2", "field3"],
@@ -47,7 +49,6 @@ def test_reject_cr_when_row_separator_is_cr_only
   end
 
   def test_liberal_parsing_with_custom_row_separator
-    # Test liberal parsing mode with custom row separator
     data = "field1,field\rwith\rcr,field3|row2,data,here|"
     expected = [
       ["field1", "field\rwith\rcr", "field3"],
@@ -56,8 +57,7 @@ def test_liberal_parsing_with_custom_row_separator
     assert_equal(expected, CSV.parse(data, row_sep: "|", liberal_parsing: true))
   end
 
-  def test_quoted_fields_with_cr_and_custom_row_separator
-    # Quoted fields should always allow \r regardless of row separator
+  def test_quoted_cr_with_custom_row_separator
     data = "field1,\"field\rwith\rcr\",field3|row2,data,here|"
     expected = [
       ["field1", "field\rwith\rcr", "field3"],

From 750531a2ae9142d0e2b18670a29fbe098ee09026 Mon Sep 17 00:00:00 2001
From: jsxs <jazndj2@gmail.com>
Date: Thu, 5 Jun 2025 17:26:14 +0900
Subject: [PATCH 06/12] refactor(parser): simplify row separator escaping per
 code review

---
 lib/csv/parser.rb | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/lib/csv/parser.rb b/lib/csv/parser.rb
index a7dd9632..7dbdcb59 100644
--- a/lib/csv/parser.rb
+++ b/lib/csv/parser.rb
@@ -677,8 +677,7 @@ def prepare_unquoted
 
       # Only exclude characters that are actually part of the row separator
       # instead of hardcoding "\r\n"
-      row_separator_chars = @row_separator.chars.map { |c| Regexp.escape(c) }.join
-      no_unquoted_values = row_separator_chars.encode(@encoding)
+      no_unquoted_values = Regexp.escape(@row_separator).encode(@encoding)
       no_unquoted_values << @escaped_first_column_separator
       unless @liberal_parsing
         no_unquoted_values << @escaped_quote_character

From f32387300eb8cf2fb3a4863796bf2fb71ed6bcb2 Mon Sep 17 00:00:00 2001
From: jsxs <jazndj2@gmail.com>
Date: Thu, 5 Jun 2025 17:31:27 +0900
Subject: [PATCH 07/12] Updated test_unquoted_cr_with_crlf_row_separator

---
 test/csv/parse/test_unquoted_cr.rb | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/test/csv/parse/test_unquoted_cr.rb b/test/csv/parse/test_unquoted_cr.rb
index fb353eb5..dde114e3 100644
--- a/test/csv/parse/test_unquoted_cr.rb
+++ b/test/csv/parse/test_unquoted_cr.rb
@@ -24,12 +24,10 @@ def test_unquoted_cr_with_custom_row_separator
   end
 
   def test_unquoted_cr_with_crlf_row_separator
-    data = "field1,field2,field3\r\nrow2,data,here\r\n"
-    expected = [
-      ["field1", "field2", "field3"],
-      ["row2", "data", "here"]
-    ]
-    assert_equal(expected, CSV.parse(data, row_sep: "\r\n"))
+    data = "field1\r,field2,field3\r\nrow2,data,here\r\n"
+    assert_raise(CSV::MalformedCSVError) do
+      CSV.parse(data, row_sep: "\r\n")
+    end
   end
 
   def test_unquoted_cr_rejected_when_included_in_row_separator

From cb1084d8be8149013f6001079b10d6789c1b621a Mon Sep 17 00:00:00 2001
From: jsxs <jazndj2@gmail.com>
Date: Thu, 5 Jun 2025 17:36:18 +0900
Subject: [PATCH 08/12] test_unquoted_cr_with_cr_row_separator test: logically
 problematic

---
 test/csv/parse/test_unquoted_cr.rb | 9 ---------
 1 file changed, 9 deletions(-)

diff --git a/test/csv/parse/test_unquoted_cr.rb b/test/csv/parse/test_unquoted_cr.rb
index dde114e3..295f75c1 100644
--- a/test/csv/parse/test_unquoted_cr.rb
+++ b/test/csv/parse/test_unquoted_cr.rb
@@ -37,15 +37,6 @@ def test_unquoted_cr_rejected_when_included_in_row_separator
     end
   end
 
-  def test_unquoted_cr_with_cr_row_separator
-    data = "field1,field2,field3\rrow2,data,here\r"
-    expected = [
-      ["field1", "field2", "field3"],
-      ["row2", "data", "here"]
-    ]
-    assert_equal(expected, CSV.parse(data, row_sep: "\r"))
-  end
-
   def test_liberal_parsing_with_custom_row_separator
     data = "field1,field\rwith\rcr,field3|row2,data,here|"
     expected = [

From f2a2f8f0e7903bee0c3ac15251b805f622168756 Mon Sep 17 00:00:00 2001
From: Jas <jazndj2@gmail.com>
Date: Thu, 5 Jun 2025 17:56:00 +0900
Subject: [PATCH 09/12] Update test/csv/parse/test_invalid.rb

Co-authored-by: Sutou Kouhei <kou@cozmixng.org>
---
 test/csv/parse/test_invalid.rb | 2 --
 1 file changed, 2 deletions(-)

diff --git a/test/csv/parse/test_invalid.rb b/test/csv/parse/test_invalid.rb
index 11e7a977..ae7c72cc 100644
--- a/test/csv/parse/test_invalid.rb
+++ b/test/csv/parse/test_invalid.rb
@@ -3,8 +3,6 @@
 require_relative "../helper"
 
 class TestCSVParseInvalid < Test::Unit::TestCase
-
-
   def test_ignore_invalid_line
     csv = CSV.new(<<-CSV, headers: true, return_headers: true)
 head1,head2,head3

From 313f849af03645970d646e5cf291501e6430a12c Mon Sep 17 00:00:00 2001
From: jsxs <jazndj2@gmail.com>
Date: Thu, 5 Jun 2025 18:05:11 +0900
Subject: [PATCH 10/12] Following better organization principles

---
 test/csv/parse/test_general.rb     | 49 +++++++++++++++++++++++--
 test/csv/parse/test_unquoted_cr.rb | 57 ------------------------------
 2 files changed, 47 insertions(+), 59 deletions(-)
 delete mode 100644 test/csv/parse/test_unquoted_cr.rb

diff --git a/test/csv/parse/test_general.rb b/test/csv/parse/test_general.rb
index e6f43e6c..5524a1c5 100644
--- a/test/csv/parse/test_general.rb
+++ b/test/csv/parse/test_general.rb
@@ -139,8 +139,53 @@ def test_non_regex_edge_cases
   end
 
   def test_unquoted_cr_with_lf_row_separator
-    result = CSV.parse_line("1,2\r,3", row_sep: "\n")
-    assert_equal(["1", "2\r", "3"], result)
+    data = "field1,field\rwith\rcr,field3\nrow2,data,here\n"
+    expected = [
+      ["field1", "field\rwith\rcr", "field3"],
+      ["row2", "data", "here"]
+    ]
+    assert_equal(expected, CSV.parse(data, row_sep: "\n"))
+  end
+
+  def test_unquoted_cr_with_custom_row_separator
+    data = "field1,field\rwith\rcr,field3|row2,data,here|"
+    expected = [
+      ["field1", "field\rwith\rcr", "field3"],
+      ["row2", "data", "here"]
+    ]
+    assert_equal(expected, CSV.parse(data, row_sep: "|"))
+  end
+
+  def test_unquoted_cr_with_crlf_row_separator
+    data = "field1\r,field2,field3\r\nrow2,data,here\r\n"
+    assert_raise(CSV::MalformedCSVError) do
+      CSV.parse(data, row_sep: "\r\n")
+    end
+  end
+
+  def test_unquoted_cr_rejected_when_included_in_row_separator
+    data = "field1,field\r2,field3\r\nrow2,data,here\r\n"
+    assert_raise(CSV::MalformedCSVError) do
+      CSV.parse(data, row_sep: "\r\n")
+    end
+  end
+
+  def test_liberal_parsing_with_unquoted_cr_and_custom_row_separator
+    data = "field1,field\rwith\rcr,field3|row2,data,here|"
+    expected = [
+      ["field1", "field\rwith\rcr", "field3"],
+      ["row2", "data", "here"]
+    ]
+    assert_equal(expected, CSV.parse(data, row_sep: "|", liberal_parsing: true))
+  end
+
+  def test_quoted_cr_with_custom_row_separator
+    data = "field1,\"field\rwith\rcr\",field3|row2,data,here|"
+    expected = [
+      ["field1", "field\rwith\rcr", "field3"],
+      ["row2", "data", "here"]
+    ]
+    assert_equal(expected, CSV.parse(data, row_sep: "|"))
   end
 
   def test_unquoted_cr_in_middle_line
diff --git a/test/csv/parse/test_unquoted_cr.rb b/test/csv/parse/test_unquoted_cr.rb
deleted file mode 100644
index 295f75c1..00000000
--- a/test/csv/parse/test_unquoted_cr.rb
+++ /dev/null
@@ -1,57 +0,0 @@
-# frozen_string_literal: false
-
-require_relative "../helper"
-
-class TestCSVParseUnquotedCR < Test::Unit::TestCase
-  extend DifferentOFS
-
-  def test_unquoted_cr_with_lf_row_separator
-    data = "field1,field\rwith\rcr,field3\nrow2,data,here\n"
-    expected = [
-      ["field1", "field\rwith\rcr", "field3"],
-      ["row2", "data", "here"]
-    ]
-    assert_equal(expected, CSV.parse(data, row_sep: "\n"))
-  end
-
-  def test_unquoted_cr_with_custom_row_separator
-    data = "field1,field\rwith\rcr,field3|row2,data,here|"
-    expected = [
-      ["field1", "field\rwith\rcr", "field3"],
-      ["row2", "data", "here"]
-    ]
-    assert_equal(expected, CSV.parse(data, row_sep: "|"))
-  end
-
-  def test_unquoted_cr_with_crlf_row_separator
-    data = "field1\r,field2,field3\r\nrow2,data,here\r\n"
-    assert_raise(CSV::MalformedCSVError) do
-      CSV.parse(data, row_sep: "\r\n")
-    end
-  end
-
-  def test_unquoted_cr_rejected_when_included_in_row_separator
-    data = "field1,field\r2,field3\r\nrow2,data,here\r\n"
-    assert_raise(CSV::MalformedCSVError) do
-      CSV.parse(data, row_sep: "\r\n")
-    end
-  end
-
-  def test_liberal_parsing_with_custom_row_separator
-    data = "field1,field\rwith\rcr,field3|row2,data,here|"
-    expected = [
-      ["field1", "field\rwith\rcr", "field3"],
-      ["row2", "data", "here"]
-    ]
-    assert_equal(expected, CSV.parse(data, row_sep: "|", liberal_parsing: true))
-  end
-
-  def test_quoted_cr_with_custom_row_separator
-    data = "field1,\"field\rwith\rcr\",field3|row2,data,here|"
-    expected = [
-      ["field1", "field\rwith\rcr", "field3"],
-      ["row2", "data", "here"]
-    ]
-    assert_equal(expected, CSV.parse(data, row_sep: "|"))
-  end
-end 

From b455a09aa5f5438d3e2ad85b427c93cae8f78424 Mon Sep 17 00:00:00 2001
From: jsxs <jazndj2@gmail.com>
Date: Thu, 5 Jun 2025 19:06:59 +0900
Subject: [PATCH 11/12] test: consolidate unquoted CR tests, remove duplication

---
 test/csv/parse/test_general.rb         | 16 ----------------
 test/csv/parse/test_liberal_parsing.rb |  9 +++++++++
 2 files changed, 9 insertions(+), 16 deletions(-)

diff --git a/test/csv/parse/test_general.rb b/test/csv/parse/test_general.rb
index 5524a1c5..03d97df0 100644
--- a/test/csv/parse/test_general.rb
+++ b/test/csv/parse/test_general.rb
@@ -156,13 +156,6 @@ def test_unquoted_cr_with_custom_row_separator
     assert_equal(expected, CSV.parse(data, row_sep: "|"))
   end
 
-  def test_unquoted_cr_with_crlf_row_separator
-    data = "field1\r,field2,field3\r\nrow2,data,here\r\n"
-    assert_raise(CSV::MalformedCSVError) do
-      CSV.parse(data, row_sep: "\r\n")
-    end
-  end
-
   def test_unquoted_cr_rejected_when_included_in_row_separator
     data = "field1,field\r2,field3\r\nrow2,data,here\r\n"
     assert_raise(CSV::MalformedCSVError) do
@@ -170,15 +163,6 @@ def test_unquoted_cr_rejected_when_included_in_row_separator
     end
   end
 
-  def test_liberal_parsing_with_unquoted_cr_and_custom_row_separator
-    data = "field1,field\rwith\rcr,field3|row2,data,here|"
-    expected = [
-      ["field1", "field\rwith\rcr", "field3"],
-      ["row2", "data", "here"]
-    ]
-    assert_equal(expected, CSV.parse(data, row_sep: "|", liberal_parsing: true))
-  end
-
   def test_quoted_cr_with_custom_row_separator
     data = "field1,\"field\rwith\rcr\",field3|row2,data,here|"
     expected = [
diff --git a/test/csv/parse/test_liberal_parsing.rb b/test/csv/parse/test_liberal_parsing.rb
index 5796d108..4300ab40 100644
--- a/test/csv/parse/test_liberal_parsing.rb
+++ b/test/csv/parse/test_liberal_parsing.rb
@@ -80,6 +80,15 @@ def test_space_quote
                  CSV.parse(input, liberal_parsing: true))
   end
 
+  def test_unquoted_cr_with_custom_row_separator
+    data = "field1,field\rwith\rcr,field3|row2,data,here|"
+    expected = [
+      ["field1", "field\rwith\rcr", "field3"],
+      ["row2", "data", "here"]
+    ]
+    assert_equal(expected, CSV.parse(data, row_sep: "|", liberal_parsing: true))
+  end
+
   def test_double_quote_outside_quote
     data = %Q{a,""b""}
     error = assert_raise(CSV::MalformedCSVError) do

From 9be946f2798d1936765fc22dc2fc06202d4c6f38 Mon Sep 17 00:00:00 2001
From: jsxs <jazndj2@gmail.com>
Date: Fri, 6 Jun 2025 13:28:30 +0900
Subject: [PATCH 12/12] Apply maintainer feedback: improve tests and clean up
 code

---
 lib/csv/parser.rb              | 2 --
 test/csv/parse/test_general.rb | 6 ++++--
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/lib/csv/parser.rb b/lib/csv/parser.rb
index 7dbdcb59..c508c8b2 100644
--- a/lib/csv/parser.rb
+++ b/lib/csv/parser.rb
@@ -675,8 +675,6 @@ def prepare_quoted
     def prepare_unquoted
       return if @quote_character.nil?
 
-      # Only exclude characters that are actually part of the row separator
-      # instead of hardcoding "\r\n"
       no_unquoted_values = Regexp.escape(@row_separator).encode(@encoding)
       no_unquoted_values << @escaped_first_column_separator
       unless @liberal_parsing
diff --git a/test/csv/parse/test_general.rb b/test/csv/parse/test_general.rb
index 03d97df0..520eb8f0 100644
--- a/test/csv/parse/test_general.rb
+++ b/test/csv/parse/test_general.rb
@@ -156,11 +156,13 @@ def test_unquoted_cr_with_custom_row_separator
     assert_equal(expected, CSV.parse(data, row_sep: "|"))
   end
 
-  def test_unquoted_cr_rejected_when_included_in_row_separator
+  def test_unquoted_cr_with_crlf_row_separator
     data = "field1,field\r2,field3\r\nrow2,data,here\r\n"
-    assert_raise(CSV::MalformedCSVError) do
+    error = assert_raise(CSV::MalformedCSVError) do
       CSV.parse(data, row_sep: "\r\n")
     end
+    assert_equal("Unquoted fields do not allow new line <\"\\r\"> in line 1.",
+                 error.message)
   end
 
   def test_quoted_cr_with_custom_row_separator