fix: decode repeated source layout escapes

agent_platform/runtime/loop.py

@@ -257,19 +257,22 @@ def decode_code_layout_escapes(content: str) -> str:
             index += 1
             continue
 
-        if content.startswith("\\r\\n", index):
+        escaped_crlf = re.match(r"\\+r\\+n", content[index:])
+        if escaped_crlf:
             output.append("\n")
-            index += 4
+            index += len(escaped_crlf.group(0))
             line_comment = False
             continue
-        if content.startswith("\\n", index):
+        escaped_newline = re.match(r"\\+n", content[index:])
+        if escaped_newline:
             output.append("\n")
-            index += 2
+            index += len(escaped_newline.group(0))
             line_comment = False
             continue
-        if content.startswith("\\t", index):
+        escaped_tab = re.match(r"\\+t", content[index:])
+        if escaped_tab:
             output.append("\t")
-            index += 2
+            index += len(escaped_tab.group(0))
             continue
         if line_comment:
             if content[index] == "\n":
@@ -297,13 +300,15 @@ def decode_code_layout_escapes(content: str) -> str:
 
 def normalize_write_file_content(path: str, content: str) -> str:
     literal_newlines = content.count("\\n") + content.count("\\r\\n")
-    actual_newlines = content.count("\n")
+    if literal_newlines < 2:
-    if literal_newlines < 2 or literal_newlines <= max(2, actual_newlines * 2):
         return content
     suffix = PurePosixPath(path).suffix.lower()
     if suffix in CODE_FILE_SUFFIXES:
         return decode_code_layout_escapes(content)
     if suffix in PLAIN_TEXT_FILE_SUFFIXES:
+        actual_newlines = content.count("\n")
+        if literal_newlines <= max(2, actual_newlines * 2):
+            return content
         return content.replace("\\r\\n", "\n").replace("\\n", "\n").replace("\\t", "\t")
     return content
 

tests/test_agent_loop.py

@@ -34,6 +34,18 @@ def test_write_file_normalizes_double_escaped_code_layout() -> None:
     )
 
 
+def test_write_file_normalizes_mixed_code_layout_without_touching_strings() -> None:
+    escaped = 'import time\nvalue = "keep\\\\ninside"\\nprint(value)\\n'
+    assert normalize_write_file_content("benchmark.py", escaped) == (
+        'import time\nvalue = "keep\\\\ninside"\nprint(value)\n'
+    )
+
+
+def test_write_file_consumes_multiple_layout_escape_layers() -> None:
+    escaped = r"import time\\n\\ndef main():\\n    print('ok')\\n"
+    assert normalize_write_file_content("benchmark.py", escaped) == ("import time\n\ndef main():\n    print('ok')\n")
+
+
 def test_write_file_normalizes_double_escaped_plain_text() -> None:
     assert normalize_write_file_content("report.md", r"# Report\n\nMeasured: 1.2 s\n") == (
         "# Report\n\nMeasured: 1.2 s\n"