M3t0r__tpl-12

diff --git a/repro.py b/repro.py
new file mode 100644
index 0000000..8fac1af
--- /dev/null
+++ b/repro.py
@@ -0,0 +1,39 @@
+
+import sys
+from tpl import main
+
+def run_tpl(template_text, args):
+    with open("test_template", "w") as f:
+        f.write(template_text)
+    
+    with open("test_output", "w") as f:
+        pass
+    
+    # Change "-" to "test_output"
+    actual_args = [arg if arg != "-" else "test_output" for arg in args]
+    
+    main(*(["tpl"] + actual_args))
+    
+    with open("test_output", "r") as f:
+        actual_output = f.read()
+    
+    return actual_output
+
+if __name__ == "__main__":
+    # Case 1: Template has newline, should result in ONE newline
+    res1 = run_tpl("hello\n", ["test_template", "-"])
+    print(f"Case 1 (with newline): expected 'hello\\n', got {repr(res1)}")
+    
+    # Case 2: Template has no newline, should result in NO newline
+    res2 = run_tpl("hello", ["test_template", "-"])
+    print(f"Case 2 (no newline): expected 'hello', got {repr(res2)}")
+
+    # Case 3: Template has two newlines, should result in TWO newlines
+    res3 = run_tpl("hello\n\n", ["test_template", "-"])
+    print(f"Case 3 (two newlines): expected 'hello\\n\\n', got {repr(res3)}")
+    
+    if res1 == "hello\n" and res2 == "hello" and res3 == "hello\n\n":
+        print("All tests passed!")
+    else:
+        print("Tests failed!")
+        sys.exit(1)
diff --git a/test_output b/test_output
new file mode 100644
index 0000000..9a80a22
--- /dev/null
+++ b/test_output
@@ -0,0 +1,2 @@
+hello
+
diff --git a/test_template b/test_template
new file mode 100644
index 0000000..9a80a22
--- /dev/null
+++ b/test_template
@@ -0,0 +1,2 @@
+hello
+
diff --git a/tpl/__init__.py b/tpl/__init__.py
index 96b6c41..afe310e 100644
--- a/tpl/__init__.py
+++ b/tpl/__init__.py
@@ -63,13 +63,13 @@ def main(*args):
 
     # create template
     with open_file(arguments[0]) as template_stream:
-        template = jinja2.Template(template_stream.read())
+        env = jinja2.Environment(keep_trailing_newline=True)
+        template = env.from_string(template_stream.read())
         template.filename = arguments[0]
 
     # and render to output
     with open_file(arguments[1], "w") as output:
         template.stream(collated_data).dump(output)
-        output.write("\n")  # does the template eat this or the dump call?
 
     return os.EX_OK
 

============================= test session starts ==============================
collected 25 items

tests/cli/test_faulty_invocations.py ...                                 [ 12%]
tests/cli/test_help_and_usage.py .....                                   [ 32%]
tests/cli/test_standard_usecases.py ................                     [ 96%]
tests/test_interface.py .                                                [100%]

==================================== PASSES ====================================
___________________________ test_key_does_not_exist ____________________________
----------------------------- Captured stdout call -----------------------------
Command: ['tpl', '/tmp/pytest-of-root/pytest-0/test_key_does_not_exist0/FOO-0']
Return code: 0
STDOUT: (stream is empty)
------------------------
========================
STDERR: (stream is empty)
------------------------
========================
Folder hierarchy:
./
|-- FOO-0
______________________________ test_corrupt_yaml _______________________________
----------------------------- Captured stdout call -----------------------------
Command: ['tpl', '--yaml', '/tmp/pytest-of-root/pytest-0/test_corrupt_yaml0/FOOnotproperlyclosed-0', '/tmp/pytest-of-root/pytest-0/test_corrupt_yaml0/FOO-0']
Return code: 1
STDOUT: (stream is empty)
------------------------
========================
STDERR:
------------------------
Traceback (most recent call last):
  File "/usr/local/bin/tpl", line 7, in <module>
    sys.exit(_argv_wrapper())
  File "/testbed/tpl/__main__.py", line 8, in _argv_wrapper
    return main(*sys.argv)
  File "/testbed/tpl/__init__.py", line 50, in main
    loaded_data = [parse_input_options(*o) for o in options]
  File "/testbed/tpl/__init__.py", line 50, in <listcomp>
    loaded_data = [parse_input_options(*o) for o in options]
  File "/testbed/tpl/__init__.py", line 163, in parse_input_options
    return parsers[type](open_file(file))
  File "/testbed/tpl/__init__.py", line 174, in load_yaml_stream
    return yaml.safe_load(stream)
  File "/usr/local/lib/python3.10/site-packages/yaml/__init__.py", line 125, in safe_load
    return load(stream, SafeLoader)
  File "/usr/local/lib/python3.10/site-packages/yaml/__init__.py", line 81, in load
    return loader.get_single_data()
  File "/usr/local/lib/python3.10/site-packages/yaml/constructor.py", line 49, in get_single_data
    node = self.get_single_node()
  File "/usr/local/lib/python3.10/site-packages/yaml/composer.py", line 35, in get_single_node
    if not self.check_event(StreamEndEvent):
  File "/usr/local/lib/python3.10/site-packages/yaml/parser.py", line 98, in check_event
    self.current_event = self.state()
  File "/usr/local/lib/python3.10/site-packages/yaml/parser.py", line 142, in parse_implicit_document_start
    if not self.check_token(DirectiveToken, DocumentStartToken,
  File "/usr/local/lib/python3.10/site-packages/yaml/scanner.py", line 116, in check_token
    self.fetch_more_tokens()
  File "/usr/local/lib/python3.10/site-packages/yaml/scanner.py", line 251, in fetch_more_tokens
    return self.fetch_double()
  File "/usr/local/lib/python3.10/site-packages/yaml/scanner.py", line 655, in fetch_double
    self.fetch_flow_scalar(style='"')
  File "/usr/local/lib/python3.10/site-packages/yaml/scanner.py", line 666, in fetch_flow_scalar
    self.tokens.append(self.scan_flow_scalar(style))
  File "/usr/local/lib/python3.10/site-packages/yaml/scanner.py", line 1151, in scan_flow_scalar
    chunks.extend(self.scan_flow_scalar_spaces(double, start_mark))
  File "/usr/local/lib/python3.10/site-packages/yaml/scanner.py", line 1238, in scan_flow_scalar_spaces
    raise ScannerError("while scanning a quoted scalar", start_mark,
yaml.scanner.ScannerError: while scanning a quoted scalar
  in "/tmp/pytest-of-root/pytest-0/test_corrupt_yaml0/FOOnotproperlyclosed-0", line 1, column 9
found unexpected end of stream
  in "/tmp/pytest-of-root/pytest-0/test_corrupt_yaml0/FOOnotproperlyclosed-0", line 1, column 29
========================
Folder hierarchy:
./
|-- FOO-0
|-- FOOnotproperlyclosed-0
______________________________ test_corrupt_json _______________________________
----------------------------- Captured stdout call -----------------------------
Command: ['tpl', '--json', '/tmp/pytest-of-root/pytest-0/test_corrupt_json0/FOOnotproperlyclosed-0', '/tmp/pytest-of-root/pytest-0/test_corrupt_json0/FOO-0']
Return code: 1
STDOUT: (stream is empty)
------------------------
========================
STDERR:
------------------------
Traceback (most recent call last):
  File "/usr/local/bin/tpl", line 7, in <module>
    sys.exit(_argv_wrapper())
  File "/testbed/tpl/__main__.py", line 8, in _argv_wrapper
    return main(*sys.argv)
  File "/testbed/tpl/__init__.py", line 50, in main
    loaded_data = [parse_input_options(*o) for o in options]
  File "/testbed/tpl/__init__.py", line 50, in <listcomp>
    loaded_data = [parse_input_options(*o) for o in options]
  File "/testbed/tpl/__init__.py", line 163, in parse_input_options
    return parsers[type](open_file(file))
  File "/testbed/tpl/__init__.py", line 179, in load_json_stream
    return json.load(stream)
  File "/usr/local/lib/python3.10/json/__init__.py", line 293, in load
    return loads(fp.read(),
  File "/usr/local/lib/python3.10/json/__init__.py", line 346, in loads
    return _default_decoder.decode(s)
  File "/usr/local/lib/python3.10/json/decoder.py", line 337, in decode
    obj, end = self.raw_decode(s, idx=_w(s, 0).end())
  File "/usr/local/lib/python3.10/json/decoder.py", line 353, in raw_decode
    obj, end = self.scan_once(s, idx)
json.decoder.JSONDecodeError: Unterminated string starting at: line 1 column 9 (char 8)
========================
Folder hierarchy:
./
|-- FOO-0
|-- FOOnotproperlyclosed-0
____________________ test_usage_and_error_without_arguments ____________________
----------------------------- Captured stdout call -----------------------------
Command: ['tpl']
Return code: 64
STDOUT: (stream is empty)
------------------------
========================
STDERR:
------------------------
No template file was specified.
Usage:
  tpl [options] <template_file>
  tpl --help
  tpl --version
========================
Folder hierarchy:
./

________________________________ test_help_on_h ________________________________
----------------------------- Captured stdout call -----------------------------
Command: ['tpl', '-h']
Return code: 0
STDOUT: (stream is empty)
------------------------
========================
STDERR:
------------------------
Usage:
  tpl [options] <template_file>
  tpl --help
  tpl --version


tpl uses the Jinja2 templating engine to render it's output. You can find the
documentation for template designers at:
    http://jinja.pocoo.org/docs/3.1.6/templates/

If you provide multiple data sources they will be merged together. If a key is
present in more than one source the value of the source that was specified
last will be used.

Options:
  -e, --environment    Use all environment variables as data
  --json=<file>        Load JSON data from a file or STDIN
  --yaml=<file>        Load YAML data from a file or STDIN
========================
Folder hierarchy:
./

______________________________ test_help_on_help _______________________________
----------------------------- Captured stdout call -----------------------------
Command: ['tpl', '--help']
Return code: 0
STDOUT: (stream is empty)
------------------------
========================
STDERR:
------------------------
Usage:
  tpl [options] <template_file>
  tpl --help
  tpl --version


tpl uses the Jinja2 templating engine to render it's output. You can find the
documentation for template designers at:
    http://jinja.pocoo.org/docs/3.1.6/templates/

If you provide multiple data sources they will be merged together. If a key is
present in more than one source the value of the source that was specified
last will be used.

Options:
  -e, --environment    Use all environment variables as data
  --json=<file>        Load JSON data from a file or STDIN
  --yaml=<file>        Load YAML data from a file or STDIN
========================
Folder hierarchy:
./

______________________________ test_version_on_v _______________________________
----------------------------- Captured stdout call -----------------------------
Command: ['tpl', '-v']
Return code: 0
STDOUT:
------------------------
tpl - 0.7+18.gb534fa5
========================
STDERR: (stream is empty)
------------------------
========================
Folder hierarchy:
./

___________________________ test_version_on_version ____________________________
----------------------------- Captured stdout call -----------------------------
Command: ['tpl', '--version']
Return code: 0
STDOUT:
------------------------
tpl - 0.7+18.gb534fa5
========================
STDERR: (stream is empty)
------------------------
========================
Folder hierarchy:
./

___________________________ test_source_environment ____________________________
----------------------------- Captured stdout call -----------------------------
Command: ['tpl', '-e', '/tmp/pytest-of-root/pytest-0/test_source_environment0/FOO-0']
Return code: 0
STDOUT: (does not end in newline
------------------------
bar
========================
STDERR: (stream is empty)
------------------------
========================
Folder hierarchy:
./
|-- FOO-0
_______________________________ test_unicode_var _______________________________
----------------------------- Captured stdout call -----------------------------
Command: ['tpl', '-e', '/tmp/pytest-of-root/pytest-0/test_unicode_var0/FOO-0']
Return code: 0
STDOUT: (does not end in newline
------------------------
🐍
========================
STDERR: (stream is empty)
------------------------
========================
Folder hierarchy:
./
|-- FOO-0
___________________________ test_shadowing_json_env ____________________________
----------------------------- Captured stdout call -----------------------------
Command: ['tpl', '--json', '/tmp/pytest-of-root/pytest-0/test_shadowing_json_env0/json-data-0', '-e', '/tmp/pytest-of-root/pytest-0/test_shadowing_json_env0/FOO-0']
Return code: 0
STDOUT: (does not end in newline
------------------------
env
========================
STDERR: (stream is empty)
------------------------
========================
Folder hierarchy:
./
|-- FOO-0
|-- json-data-0
___________________________ test_shadowing_yaml_env ____________________________
----------------------------- Captured stdout call -----------------------------
Command: ['tpl', '--yaml', '/tmp/pytest-of-root/pytest-0/test_shadowing_yaml_env0/yaml-data-0', '-e', '/tmp/pytest-of-root/pytest-0/test_shadowing_yaml_env0/FOO-0']
Return code: 0
STDOUT: (does not end in newline
------------------------
env
========================
STDERR: (stream is empty)
------------------------
========================
Folder hierarchy:
./
|-- yaml-data-0
|-- FOO-0
_____________________________ test_yaml_flow_style _____________________________
----------------------------- Captured stdout call -----------------------------
Command: ['tpl', '--yaml', '/tmp/pytest-of-root/pytest-0/test_yaml_flow_style0/FOOyaml-0', '/tmp/pytest-of-root/pytest-0/test_yaml_flow_style0/FOO-0']
Return code: 0
STDOUT: (does not end in newline
------------------------
yaml
========================
STDERR: (stream is empty)
------------------------
========================
Folder hierarchy:
./
|-- FOO-0
|-- FOOyaml-0
_________________________ test_environment_by_default __________________________
----------------------------- Captured stdout call -----------------------------
Command: ['tpl', '/tmp/pytest-of-root/pytest-0/test_environment_by_default0/FOO-0']
Return code: 0
STDOUT: (does not end in newline
------------------------
bar
========================
STDERR: (stream is empty)
------------------------
========================
Folder hierarchy:
./
|-- FOO-0
___________________________ test_sub_dict_shadowing ____________________________
----------------------------- Captured stdout call -----------------------------
Command: ['tpl', '--json', '/tmp/pytest-of-root/pytest-0/test_sub_dict_shadowing0/json-data-0', '--json', '/tmp/pytest-of-root/pytest-0/test_sub_dict_shadowing0/json-data-1', '/tmp/pytest-of-root/pytest-0/test_sub_dict_shadowing0/FOOBAR-0']
Return code: 0
STDOUT: (does not end in newline
------------------------
second
========================
STDERR: (stream is empty)
------------------------
========================
Folder hierarchy:
./
|-- json-data-1
|-- FOOBAR-0
|-- json-data-0
____________________________ test_sub_dict_merging _____________________________
----------------------------- Captured stdout call -----------------------------
Command: ['tpl', '--json', '/tmp/pytest-of-root/pytest-0/test_sub_dict_merging0/json-data-0', '--json', '/tmp/pytest-of-root/pytest-0/test_sub_dict_merging0/json-data-1', '/tmp/pytest-of-root/pytest-0/test_sub_dict_merging0/mergeFOOmergeBAR-0']
Return code: 0
STDOUT: (does not end in newline
------------------------
foobar
========================
STDERR: (stream is empty)
------------------------
========================
Folder hierarchy:
./
|-- json-data-1
|-- mergeFOOmergeBAR-0
|-- json-data-0
________________________ test_second_sub_dict_shadowing ________________________
----------------------------- Captured stdout call -----------------------------
Command: ['tpl', '--json', '/tmp/pytest-of-root/pytest-0/test_second_sub_dict_shadowing0/json-data-0', '--json', '/tmp/pytest-of-root/pytest-0/test_second_sub_dict_shadowing0/json-data-1', '/tmp/pytest-of-root/pytest-0/test_second_sub_dict_shadowing0/merge.deeper.overwritten-0']
Return code: 0
STDOUT: (does not end in newline
------------------------
bar
========================
STDERR: (stream is empty)
------------------------
========================
Folder hierarchy:
./
|-- merge.deeper.overwritten-0
|-- json-data-1
|-- json-data-0
_________________________ test_second_sub_dict_merging _________________________
----------------------------- Captured stdout call -----------------------------
Command: ['tpl', '--json', '/tmp/pytest-of-root/pytest-0/test_second_sub_dict_merging0/json-data-0', '--json', '/tmp/pytest-of-root/pytest-0/test_second_sub_dict_merging0/json-data-1', '/tmp/pytest-of-root/pytest-0/test_second_sub_dict_merging0/merge.deeper.FOOmerge.deeper.BAR-0']
Return code: 0
STDOUT: (does not end in newline
------------------------
foobar
========================
STDERR: (stream is empty)
------------------------
========================
Folder hierarchy:
./
|-- json-data-1
|-- json-data-0
|-- merge.deeper.FOOmerge.deeper.BAR-0
____________________________ test_shadowing_of_dict ____________________________
----------------------------- Captured stdout call -----------------------------
Command: ['tpl', '--json', '/tmp/pytest-of-root/pytest-0/test_shadowing_of_dict0/json-data-0', '--json', '/tmp/pytest-of-root/pytest-0/test_shadowing_of_dict0/json-data-1', '/tmp/pytest-of-root/pytest-0/test_shadowing_of_dict0/merge-0']
Return code: 0
STDOUT: (does not end in newline
------------------------
bar
========================
STDERR: (stream is empty)
------------------------
========================
Folder hierarchy:
./
|-- merge-0
|-- json-data-1
|-- json-data-0
_________________________ test_keep_no_newline_at_end __________________________
----------------------------- Captured stdout call -----------------------------
Command: ['tpl', '/tmp/pytest-of-root/pytest-0/test_keep_no_newline_at_end0/FOO-0']
Return code: 0
STDOUT: (does not end in newline
------------------------
bar
========================
STDERR: (stream is empty)
------------------------
========================
Folder hierarchy:
./
|-- FOO-0
_________________________ test_keep_one_newline_at_end _________________________
----------------------------- Captured stdout call -----------------------------
Command: ['tpl', '/tmp/pytest-of-root/pytest-0/test_keep_one_newline_at_end0/FOO-0']
Return code: 0
STDOUT:
------------------------
bar
========================
STDERR: (stream is empty)
------------------------
========================
Folder hierarchy:
./
|-- FOO-0
________________________ test_keep_two_newlines_at_end _________________________
----------------------------- Captured stdout call -----------------------------
Command: ['tpl', '/tmp/pytest-of-root/pytest-0/test_keep_two_newlines_at_end0/FOO-0']
Return code: 0
STDOUT:
------------------------
bar

========================
STDERR: (stream is empty)
------------------------
========================
Folder hierarchy:
./
|-- FOO-0
______________________ test_keep_one_newline_at_beginning ______________________
----------------------------- Captured stdout call -----------------------------
Command: ['tpl', '/tmp/pytest-of-root/pytest-0/test_keep_one_newline_at_begin0/FOO-0']
Return code: 0
STDOUT: (does not end in newline
------------------------

bar
========================
STDERR: (stream is empty)
------------------------
========================
Folder hierarchy:
./
|-- FOO-0
_____________________ test_keep_two_newlines_at_beginning ______________________
----------------------------- Captured stdout call -----------------------------
Command: ['tpl', '/tmp/pytest-of-root/pytest-0/test_keep_two_newlines_at_begi0/FOO-0']
Return code: 0
STDOUT: (does not end in newline
------------------------


bar
========================
STDERR: (stream is empty)
------------------------
========================
Folder hierarchy:
./
|-- FOO-0
- generated xml file: /tmp/rebench-grade-11ca139ec2ea44298f1d779275c9a1d7.xml --
=========================== short test summary info ============================
PASSED tests/cli/test_faulty_invocations.py::test_key_does_not_exist
PASSED tests/cli/test_faulty_invocations.py::test_corrupt_yaml
PASSED tests/cli/test_faulty_invocations.py::test_corrupt_json
PASSED tests/cli/test_help_and_usage.py::test_usage_and_error_without_arguments
PASSED tests/cli/test_help_and_usage.py::test_help_on_h
PASSED tests/cli/test_help_and_usage.py::test_help_on_help
PASSED tests/cli/test_help_and_usage.py::test_version_on_v
PASSED tests/cli/test_help_and_usage.py::test_version_on_version
PASSED tests/cli/test_standard_usecases.py::test_source_environment
PASSED tests/cli/test_standard_usecases.py::test_unicode_var
PASSED tests/cli/test_standard_usecases.py::test_shadowing_json_env
PASSED tests/cli/test_standard_usecases.py::test_shadowing_yaml_env
PASSED tests/cli/test_standard_usecases.py::test_yaml_flow_style
PASSED tests/cli/test_standard_usecases.py::test_environment_by_default
PASSED tests/cli/test_standard_usecases.py::test_sub_dict_shadowing
PASSED tests/cli/test_standard_usecases.py::test_sub_dict_merging
PASSED tests/cli/test_standard_usecases.py::test_second_sub_dict_shadowing
PASSED tests/cli/test_standard_usecases.py::test_second_sub_dict_merging
PASSED tests/cli/test_standard_usecases.py::test_shadowing_of_dict
PASSED tests/cli/test_standard_usecases.py::test_keep_no_newline_at_end
PASSED tests/cli/test_standard_usecases.py::test_keep_one_newline_at_end
PASSED tests/cli/test_standard_usecases.py::test_keep_two_newlines_at_end
PASSED tests/cli/test_standard_usecases.py::test_keep_one_newline_at_beginning
PASSED tests/cli/test_standard_usecases.py::test_keep_two_newlines_at_beginning
PASSED tests/test_interface.py::test_current_help_in_readme
============================== 25 passed in 1.50s ==============================

<?xml version="1.0" encoding="utf-8"?><testsuites><testsuite name="pytest" errors="0" failures="0" skipped="0" tests="25" time="1.500" timestamp="2026-11-14T04:18:49.427045+00:00" hostname="84810e7a50d9"><testcase classname="tests.cli.test_faulty_invocations" name="test_key_does_not_exist" time="0.215" /><testcase classname="tests.cli.test_faulty_invocations" name="test_corrupt_yaml" time="0.050" /><testcase classname="tests.cli.test_faulty_invocations" name="test_corrupt_json" time="0.050" /><testcase classname="tests.cli.test_help_and_usage" name="test_usage_and_error_without_arguments" time="0.048" /><testcase classname="tests.cli.test_help_and_usage" name="test_help_on_h" time="0.048" /><testcase classname="tests.cli.test_help_and_usage" name="test_help_on_help" time="0.047" /><testcase classname="tests.cli.test_help_and_usage" name="test_version_on_v" time="0.048" /><testcase classname="tests.cli.test_help_and_usage" name="test_version_on_version" time="0.049" /><testcase classname="tests.cli.test_standard_usecases" name="test_source_environment" time="0.050" /><testcase classname="tests.cli.test_standard_usecases" name="test_unicode_var" time="0.049" /><testcase classname="tests.cli.test_standard_usecases" name="test_shadowing_json_env" time="0.049" /><testcase classname="tests.cli.test_standard_usecases" name="test_shadowing_yaml_env" time="0.049" /><testcase classname="tests.cli.test_standard_usecases" name="test_yaml_flow_style" time="0.050" /><testcase classname="tests.cli.test_standard_usecases" name="test_environment_by_default" time="0.049" /><testcase classname="tests.cli.test_standard_usecases" name="test_sub_dict_shadowing" time="0.050" /><testcase classname="tests.cli.test_standard_usecases" name="test_sub_dict_merging" time="0.050" /><testcase classname="tests.cli.test_standard_usecases" name="test_second_sub_dict_shadowing" time="0.049" /><testcase classname="tests.cli.test_standard_usecases" name="test_second_sub_dict_merging" time="0.049" /><testcase classname="tests.cli.test_standard_usecases" name="test_shadowing_of_dict" time="0.050" /><testcase classname="tests.cli.test_standard_usecases" name="test_keep_no_newline_at_end" time="0.049" /><testcase classname="tests.cli.test_standard_usecases" name="test_keep_one_newline_at_end" time="0.049" /><testcase classname="tests.cli.test_standard_usecases" name="test_keep_two_newlines_at_end" time="0.049" /><testcase classname="tests.cli.test_standard_usecases" name="test_keep_one_newline_at_beginning" time="0.049" /><testcase classname="tests.cli.test_standard_usecases" name="test_keep_two_newlines_at_beginning" time="0.049" /><testcase classname="tests.test_interface" name="test_current_help_in_readme" time="0.001" /></testsuite></testsuites>

  [   0.0s] 📋 System Prompt: You are a principal Python software engineer resolving a repository issue in `/workspace`.
  [   0.0s] 🎯 Task Prompt: You are evaluating a software engineering task for repository M3t0r/tpl.
  [   8.5s] 💭 (323 chars) "The user wants to fix a trailing newline issue in the `tpl` library.
The problem statement points to `tpl/__init__.py` a..."
  [   8.5s] 🔧 run_command grep -rn --include="*.py" "jinja2.Environment" .
  [   8.5s]   → error (exit 0): 
  [  13.3s] 💭 (189 chars) "Ah, maybe it doesn't explicitly use `jinja2.Environment` in the code, but uses a wrapper or 
a function from Jinja.
Let's..."
  [  13.3s] 📖 read_file (tpl/__init__.py)
  [  13.3s]   ✓ {'status': 'ok', 'filepath': 'tpl/__init__.py', 'content': 'import sys\nimport os\nfrom getopt import 
getopt\nimport jso…
  [  77.3s] 💭 (3135 chars) "I found the culprit:
```python
    # and render to output
    with open_file(arguments[1], "w") as output:
        templ..."
  [  77.3s] 🔧 run_command (18 lines) python3 - <<'PY'
  [  77.5s]   → Template: 'hello\n' | Expected newline: True | Actual: True
  [  87.5s] 💭 (139 chars) "Okay, so `jinja2.Environment(keep_trailing_newline=True)` behaves as desired.

Now let's see if `jinja2.Template` does t..."
  [  87.5s] 🔧 run_command (16 lines) python3 - <<'PY'
  [  87.6s]   → error (exit 0): 
  [  99.1s] 💭 (318 chars) "Wait! `jinja2.Template("hello\n").render({})` produced `hello` (no newline).
Wait, let me check carefully.
`Template: 'h..."
  [  99.1s] 🔧 run_command (5 lines) python3 - <<'PY'
  [  99.2s]   → Default keep_trailing_newline: False
  [ 128.6s] 💭 (1805 chars) "Aha! `keep_trailing_newline` defaults to `False` in the environment of the installed Jinja2
version.

So, to fix this:
1..."
  [ 128.6s] 📖 read_file (tpl/__init__.py)
  [ 128.6s]   ✓ {'status': 'ok', 'filepath': 'tpl/__init__.py', 'content': '\ndef parse_input_options(type, file):\n    
if type in ["-e"…
  [ 167.1s] 💭 (160 chars) "Okay, so `open_file` is simple.

Now I will create a reproduction test case.
I'll create a file `repro.py` to test the c..."
  [ 167.1s] 📝 write_file (repro.py, 34 lines)
  [ 167.3s]   ✓ {'status': 'ok', 'filepath': 'repro.py', 'size': 1162}
  [ 224.3s] 💭 (1599 chars) "Now run it to see it fail.
Wait, `main` in `tpl/__init__.py` calls `parse_input_options` and handles `options`.
Actually..."
  [ 224.3s] 📝 write_file (repro.py, 37 lines)
  [ 224.4s]   ✓ {'status': 'ok', 'filepath': 'repro.py', 'size': 1161}
  [ 227.4s] 💭 (11 chars) "Now run it."
  [ 227.4s] 🔧 run_command python3 repro.py
  [ 227.6s]   → error (exit 0): 
  [ 246.0s] 💭 (761 chars) "Wait, why does it say "No template file was specified"?
The code in `main`:
```python
def main(*args):
    options, argu..."
  [ 246.0s] ✏️ edit_file (repro.py)
  [ 246.1s]   ✓ {'status': 'ok', 'filepath': 'repro.py', 'occurrences': 1, 'strategy': 'exact', 'diff': '--- 
a/repro.py\n+++ b/repro.py\…
  [ 247.0s] 💭 (17 chars) "Now run it again."
  [ 247.0s] 🔧 run_command python3 repro.py
  [ 247.1s]   → error (exit 0): 
  [ 301.0s] 💭 (1274 chars) "Ah, I'm calling `main` which probably closes stdout if `arguments[1] == "-"`.
Wait, `tpl/__init__.py`:
```python
def ope..."
  [ 301.0s] ✏️ edit_file (repro.py)
  [ 301.0s]   ❌ {'status': 'error', 'error_type': 'FileEditError', 'error_message': "Failed to replace: old_string not 
found. Ensure you…
  [ 318.6s] 💭 (119 chars) "I messed up the `old_string` because I had already modified `repro.py` once.
Let me just overwrite `repro.py` entirely."
  [ 318.6s] 📝 write_file (repro.py, 35 lines)
  [ 318.8s]   ✓ {'status': 'ok', 'filepath': 'repro.py', 'size': 1022}
  [ 320.4s] 💭 (11 chars) "Now run it."
  [ 320.4s] 🔧 run_command python3 repro.py
  [ 320.4s]   → error (exit 0): 
  [ 350.7s] 💭 (715 chars) "Wait, look at Case 1:
`Case 1 (with newline): expected 'hello\n', got 'hello\n'`
Wait, if the template is `hello\n`, the..."
  [ 350.7s] 🔧 run_command (6 lines) python3 - <<'PY'
  [ 350.8s]   → error (exit 0): 
  [ 358.2s] 💭 (29 chars) "My bad, f-string restriction."
  [ 358.2s] 🔧 run_command (6 lines) python3 - <<'PY'
  [ 358.3s]   → Template 'hello\n' -> 'hello'
  [ 369.8s] 💭 (167 chars) "Yes, it strips the trailing newline.

So, as I suspected:
1. Use `jinja2.Environment(keep_trailing_newline=True)`.
2. re..."
  [ 369.8s] ✏️ edit_file (tpl/__init__.py)
  [ 369.9s]   ✓ {'status': 'ok', 'filepath': 'tpl/__init__.py', 'occurrences': 1, 'strategy': 'exact', 'diff': '--- 
a/tpl/__init__.py\n+…
  [ 371.6s] 💭 (44 chars) "Now let's run the reproduction script again."
  [ 371.6s] 🔧 run_command python3 repro.py
  [ 371.7s]   → Case 1 (with newline): expected 'hello\n', got 'hello\n'
  [ 396.7s] 💭 (68 chars) "Great! Now I should verify it with a template that has TWO newlines."
  [ 396.7s] ✏️ edit_file (repro.py)
  [ 396.8s]   ✓ {'status': 'ok', 'filepath': 'repro.py', 'occurrences': 1, 'strategy': 'exact', 'diff': '--- 
a/repro.py\n+++ b/repro.py\…
  [ 398.1s] 💭 (7 chars) "Run it."
  [ 398.1s] 🔧 run_command python3 repro.py
  [ 398.2s]   → Case 1 (with newline): expected 'hello\n', got 'hello\n'
  [ 415.0s] 💭 (802 chars) "Perfect. Now I should clean up `repro.py` and check for other possible issues.
The task also said: "We should add tests ..."
  [ 415.0s] 🔧 run_command ls -R tests/
  [ 415.1s]   → tests/: