deploy_environment: add CRLF / lone-CR newline tests

Per @guill review on PR #13425: add tests covering Windows-style line
endings, since editors often save files with CRLF and we want to confirm
the CR never leaks into the returned value.

- `_write_env_file` now opens with `newline=""` so the on-disk bytes
  match the literal string passed in (deterministic across host OSes,
  no `\n` -> `\r\n` translation on Windows).

New tests:
- `test_crlf_line_ending`: `"...\r\n"` -> value (no trailing CR).
- `test_crlf_multiline_only_first_line_used`: `readline(128)` stops at
  the translated newline boundary for CRLF lines.
- `test_crlf_with_surrounding_whitespace`: leading/trailing spaces +
  CRLF still yield the bare value.
- `test_lone_cr_line_ending`: classic-Mac / legacy editor `"...\r"`
  is also handled by universal-newlines decoding.

15/15 unit tests pass.

Co-authored-by: Amp <amp@ampcode.com>
Amp-Thread-ID: https://ampcode.com/threads/T-019df5a8-36be-7107-a4af-c7e4f51687df

tests-unit/deploy_environment_test.py

@@ -18,8 +18,14 @@ def _reset_cache_and_install_dir(tmp_path, monkeypatch):
 
 
 def _write_env_file(tmp_path, content: str) -> str:
+    """Write the env file with exact content (no newline translation).
+
+    `newline=""` disables Python's text-mode newline translation so the bytes
+    on disk match the literal string passed in, regardless of host OS.
+    Newline-style tests (CRLF, lone CR) rely on this.
+    """
     path = os.path.join(str(tmp_path), ".comfy_environment")
-    with open(path, "w", encoding="utf-8") as f:
+    with open(path, "w", encoding="utf-8", newline="") as f:
         f.write(content)
     return path
 
@@ -40,6 +46,26 @@ class TestGetDeployEnvironment:
         _write_env_file(tmp_path, "first-line\nsecond-line\n")
         assert get_deploy_environment() == "first-line"
 
+    def test_crlf_line_ending(self, tmp_path):
+        # Windows editors often save text files with CRLF line endings.
+        # The CR must not end up in the returned value.
+        _write_env_file(tmp_path, "local-desktop2-standalone\r\n")
+        assert get_deploy_environment() == "local-desktop2-standalone"
+
+    def test_crlf_multiline_only_first_line_used(self, tmp_path):
+        _write_env_file(tmp_path, "first-line\r\nsecond-line\r\n")
+        assert get_deploy_environment() == "first-line"
+
+    def test_crlf_with_surrounding_whitespace(self, tmp_path):
+        _write_env_file(tmp_path, "  local-desktop2-standalone  \r\n")
+        assert get_deploy_environment() == "local-desktop2-standalone"
+
+    def test_lone_cr_line_ending(self, tmp_path):
+        # Classic-Mac / some legacy editors use a bare CR.
+        # Universal-newlines decoding treats it as a line terminator too.
+        _write_env_file(tmp_path, "local-desktop2-standalone\r")
+        assert get_deploy_environment() == "local-desktop2-standalone"
+
     def test_empty_file_falls_back_to_default(self, tmp_path):
         _write_env_file(tmp_path, "")
         assert get_deploy_environment() == "local-git"