We are currently solving the following issue within our repository. Here is the issue text:
--- BEGIN ISSUE ---
Cannot copy file .php in files folder.
Using nikola 7.1.0, I couldn't copy a file contact.php in the default files folder.
This are the error massage:

$ nikola build
Scanning posts............done!
.  copy_files:output/contact.php
###### 

TaskError - taskid:copy_files:output/contact.php
PythonAction Error
Traceback (most recent call last):
  File "/home/binhasan/local/lib/python2.7/site-packages/doit/action.py", line 365, in execute
    returned_value = self.py_callable(_self.args, *_kwargs)
  File "/home/binhasan/local/lib/python2.7/site-packages/nikola/utils.py", line 825, in unlessLink
    action(target)
  File "/home/binhasan/local/lib/python2.7/site-packages/nikola/filters.py", line 67, in f_in_file
    data = f(data)
  File "/home/binhasan/local/lib/python2.7/site-packages/nikola/filters.py", line 183, in php_template_injection
    return phpdata
UnboundLocalError: local variable 'phpdata' referenced before assignment


--- END ISSUE ---

Below are some code segments, each from a relevant file. One or more of these files may contain bugs.
--- BEGIN FILES ---
Path: `nikola/filters.py`
Content:
```
1 # -*- coding: utf-8 -*-
2 
3 # Copyright © 2012-2014 Roberto Alsina and others.
4 
5 # Permission is hereby granted, free of charge, to any
6 # person obtaining a copy of this software and associated
7 # documentation files (the "Software"), to deal in the
8 # Software without restriction, including without limitation
9 # the rights to use, copy, modify, merge, publish,
10 # distribute, sublicense, and/or sell copies of the
11 # Software, and to permit persons to whom the Software is
12 # furnished to do so, subject to the following conditions:
13 #
14 # The above copyright notice and this permission notice
15 # shall be included in all copies or substantial portions of
16 # the Software.
17 #
18 # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY
19 # KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
20 # WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
21 # PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS
22 # OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
23 # OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
24 # OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
25 # SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
26 
27 """Utility functions to help you run filters on files."""
28 
29 from .utils import req_missing
30 from functools import wraps
31 import os
32 import io
33 import shutil
34 import subprocess
35 import tempfile
36 import shlex
37 
38 try:
39     import typogrify.filters as typo
40 except ImportError:
41     typo = None  # NOQA
42 
43 
44 def apply_to_binary_file(f):
45     """Take a function f that transforms a data argument, and returns
46     a function that takes a filename and applies f to the contents,
47     in place.  Reads files in binary mode."""
48     @wraps(f)
49     def f_in_file(fname):
50         with open(fname, 'rb') as inf:
51             data = inf.read()
52         data = f(data)
53         with open(fname, 'wb+') as outf:
54             outf.write(data)
55 
56     return f_in_file
57 
58 
59 def apply_to_text_file(f):
60     """Take a function f that transforms a data argument, and returns
61     a function that takes a filename and applies f to the contents,
62     in place.  Reads files in UTF-8."""
63     @wraps(f)
64     def f_in_file(fname):
65         with io.open(fname, 'r', encoding='utf-8') as inf:
66             data = inf.read()
67         data = f(data)
68         with io.open(fname, 'w+', encoding='utf-8') as outf:
69             outf.write(data)
70 
71     return f_in_file
72 
73 
74 def list_replace(the_list, find, replacement):
75     "Replace all occurrences of ``find`` with ``replacement`` in ``the_list``"
76     for i, v in enumerate(the_list):
77         if v == find:
78             the_list[i] = replacement
79 
80 
81 def runinplace(command, infile):
82     """Run a command in-place on a file.
83 
84     command is a string of the form: "commandname %1 %2" and
85     it will be execed with infile as %1 and a temporary file
86     as %2. Then, that temporary file will be moved over %1.
87 
88     Example usage:
89 
90     runinplace("yui-compressor %1 -o %2", "myfile.css")
91 
92     That will replace myfile.css with a minified version.
93 
94     You can also supply command as a list.
95     """
96 
97     if not isinstance(command, list):
98         command = shlex.split(command)
99 
100     tmpdir = None
101 
102     if "%2" in command:
103         tmpdir = tempfile.mkdtemp(prefix="nikola")
104         tmpfname = os.path.join(tmpdir, os.path.basename(infile))
105 
106     try:
107         list_replace(command, "%1", infile)
108         if tmpdir:
109             list_replace(command, "%2", tmpfname)
110 
111         subprocess.check_call(command)
112 
113         if tmpdir:
114             shutil.move(tmpfname, infile)
115     finally:
116         if tmpdir:
117             shutil.rmtree(tmpdir)
118 
119 
120 def yui_compressor(infile):
121     yuicompressor = False
122     try:
123         subprocess.call('yui-compressor', stdout=open(os.devnull, 'w'), stderr=open(os.devnull, 'w'))
124         yuicompressor = 'yui-compressor'
125     except Exception:
126         pass
127     if not yuicompressor:
128         try:
129             subprocess.call('yuicompressor', stdout=open(os.devnull, 'w'), stderr=open(os.devnull, 'w'))
130             yuicompressor = 'yuicompressor'
131         except:
132             raise Exception("yui-compressor is not installed.")
133             return False
134 
135     return runinplace(r'{} --nomunge %1 -o %2'.format(yuicompressor), infile)
136 
137 
138 def closure_compiler(infile):
139     return runinplace(r'closure-compiler --warning_level QUIET --js %1 --js_output_file %2', infile)
140 
141 
142 def optipng(infile):
143     return runinplace(r"optipng -preserve -o2 -quiet %1", infile)
144 
145 
146 def jpegoptim(infile):
147     return runinplace(r"jpegoptim -p --strip-all -q %1", infile)
148 
149 
150 @apply_to_text_file
151 def minify_lines(data):
152     datalines = data.splitlines()
153     datalines = [line.lstrip() for line in datalines if not (line.strip() == "")]
154     return "\n".join(datalines)
155 
156 
157 @apply_to_text_file
158 def typogrify(data):
159     if typo is None:
160         req_missing(['typogrify'], 'use the typogrify filter')
161 
162     data = typo.amp(data)
163     data = typo.widont(data)
164     data = typo.smartypants(data)
165     # Disabled because of typogrify bug where it breaks <title>
166     # data = typo.caps(data)
167     data = typo.initial_quotes(data)
168     return data
169 
170 
171 @apply_to_text_file
172 def php_template_injection(data):
173     import re
174     template = re.search('<\!-- __NIKOLA_PHP_TEMPLATE_INJECTION source\:(.*) checksum\:(.*)__ -->', data)
175     if template:
176         source = template.group(1)
177         with io.open(source, "r", encoding="utf-8") as in_file:
178             phpdata = in_file.read()
179         _META_SEPARATOR = '(' + os.linesep * 2 + '|' + ('\n' * 2) + '|' + ("\r\n" * 2) + ')'
180         phpdata = re.split(_META_SEPARATOR, phpdata, maxsplit=1)[-1]
181         phpdata = re.sub(template.group(0), phpdata, data)
182 
183     return phpdata
184
```
--- END FILES ---

Please first localize the bug based on the issue statement, and then generate a patch according to the `git diff` format fenced by three backticks.

Here is an example:

```diff
diff --git a/examples/server_async.py b/examples/server_async.py
--- a/examples/server_async.py
+++ b/examples/server_async.py
@@ -313,4 +313,4 @@
 
 
 if __name__ == "__main__":
-    asyncio.run(run_async_server("."), debug=True)
+    asyncio.run(run_async_server(), debug=True)
diff --git a/examples/server_sync.py b/examples/server_sync.py
--- a/examples/server_sync.py
+++ b/examples/server_sync.py
@@ -313,5 +313,5 @@
 
 
 if __name__ == "__main__":
-    server = run_sync_server(".")
+    server = run_sync_server()
     server.shutdown()

```

diff --git a/nikola/filters.py b/nikola/filters.py
--- a/nikola/filters.py
+++ b/nikola/filters.py
@@ -179,5 +179,6 @@
         _META_SEPARATOR = '(' + os.linesep * 2 + '|' + ('\n' * 2) + '|' + ("\r\n" * 2) + ')'
         phpdata = re.split(_META_SEPARATOR, phpdata, maxsplit=1)[-1]
         phpdata = re.sub(template.group(0), phpdata, data)
-
-    return phpdata
+        return phpdata
+    else:
+        return data

{"golden_diff": "diff --git a/nikola/filters.py b/nikola/filters.py\n--- a/nikola/filters.py\n+++ b/nikola/filters.py\n@@ -179,5 +179,6 @@\n         _META_SEPARATOR = '(' + os.linesep * 2 + '|' + ('\\n' * 2) + '|' + (\"\\r\\n\" * 2) + ')'\n         phpdata = re.split(_META_SEPARATOR, phpdata, maxsplit=1)[-1]\n         phpdata = re.sub(template.group(0), phpdata, data)\n-\n-    return phpdata\n+        return phpdata\n+    else:\n+        return data\n", "issue": "Cannot copy file .php in files folder.\nUsing nikola 7.1.0, I couldn't copy a file contact.php in the default files folder.\nThis are the error massage:\n\n$ nikola build\nScanning posts............done!\n.  copy_files:output/contact.php\n###### \n\nTaskError - taskid:copy_files:output/contact.php\nPythonAction Error\nTraceback (most recent call last):\n  File \"/home/binhasan/local/lib/python2.7/site-packages/doit/action.py\", line 365, in execute\n    returned_value = self.py_callable(_self.args, *_kwargs)\n  File \"/home/binhasan/local/lib/python2.7/site-packages/nikola/utils.py\", line 825, in unlessLink\n    action(target)\n  File \"/home/binhasan/local/lib/python2.7/site-packages/nikola/filters.py\", line 67, in f_in_file\n    data = f(data)\n  File \"/home/binhasan/local/lib/python2.7/site-packages/nikola/filters.py\", line 183, in php_template_injection\n    return phpdata\nUnboundLocalError: local variable 'phpdata' referenced before assignment\n\n", "before_files": [{"content": "# -*- coding: utf-8 -*-\n\n# Copyright \u00a9 2012-2014 Roberto Alsina and others.\n\n# Permission is hereby granted, free of charge, to any\n# person obtaining a copy of this software and associated\n# documentation files (the \"Software\"), to deal in the\n# Software without restriction, including without limitation\n# the rights to use, copy, modify, merge, publish,\n# distribute, sublicense, and/or sell copies of the\n# Software, and to permit persons to whom the Software is\n# furnished to do so, subject to the following conditions:\n#\n# The above copyright notice and this permission notice\n# shall be included in all copies or substantial portions of\n# the Software.\n#\n# THE SOFTWARE IS PROVIDED \"AS IS\", WITHOUT WARRANTY OF ANY\n# KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE\n# WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR\n# PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS\n# OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR\n# OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR\n# OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE\n# SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.\n\n\"\"\"Utility functions to help you run filters on files.\"\"\"\n\nfrom .utils import req_missing\nfrom functools import wraps\nimport os\nimport io\nimport shutil\nimport subprocess\nimport tempfile\nimport shlex\n\ntry:\n    import typogrify.filters as typo\nexcept ImportError:\n    typo = None  # NOQA\n\n\ndef apply_to_binary_file(f):\n    \"\"\"Take a function f that transforms a data argument, and returns\n    a function that takes a filename and applies f to the contents,\n    in place.  Reads files in binary mode.\"\"\"\n    @wraps(f)\n    def f_in_file(fname):\n        with open(fname, 'rb') as inf:\n            data = inf.read()\n        data = f(data)\n        with open(fname, 'wb+') as outf:\n            outf.write(data)\n\n    return f_in_file\n\n\ndef apply_to_text_file(f):\n    \"\"\"Take a function f that transforms a data argument, and returns\n    a function that takes a filename and applies f to the contents,\n    in place.  Reads files in UTF-8.\"\"\"\n    @wraps(f)\n    def f_in_file(fname):\n        with io.open(fname, 'r', encoding='utf-8') as inf:\n            data = inf.read()\n        data = f(data)\n        with io.open(fname, 'w+', encoding='utf-8') as outf:\n            outf.write(data)\n\n    return f_in_file\n\n\ndef list_replace(the_list, find, replacement):\n    \"Replace all occurrences of ``find`` with ``replacement`` in ``the_list``\"\n    for i, v in enumerate(the_list):\n        if v == find:\n            the_list[i] = replacement\n\n\ndef runinplace(command, infile):\n    \"\"\"Run a command in-place on a file.\n\n    command is a string of the form: \"commandname %1 %2\" and\n    it will be execed with infile as %1 and a temporary file\n    as %2. Then, that temporary file will be moved over %1.\n\n    Example usage:\n\n    runinplace(\"yui-compressor %1 -o %2\", \"myfile.css\")\n\n    That will replace myfile.css with a minified version.\n\n    You can also supply command as a list.\n    \"\"\"\n\n    if not isinstance(command, list):\n        command = shlex.split(command)\n\n    tmpdir = None\n\n    if \"%2\" in command:\n        tmpdir = tempfile.mkdtemp(prefix=\"nikola\")\n        tmpfname = os.path.join(tmpdir, os.path.basename(infile))\n\n    try:\n        list_replace(command, \"%1\", infile)\n        if tmpdir:\n            list_replace(command, \"%2\", tmpfname)\n\n        subprocess.check_call(command)\n\n        if tmpdir:\n            shutil.move(tmpfname, infile)\n    finally:\n        if tmpdir:\n            shutil.rmtree(tmpdir)\n\n\ndef yui_compressor(infile):\n    yuicompressor = False\n    try:\n        subprocess.call('yui-compressor', stdout=open(os.devnull, 'w'), stderr=open(os.devnull, 'w'))\n        yuicompressor = 'yui-compressor'\n    except Exception:\n        pass\n    if not yuicompressor:\n        try:\n            subprocess.call('yuicompressor', stdout=open(os.devnull, 'w'), stderr=open(os.devnull, 'w'))\n            yuicompressor = 'yuicompressor'\n        except:\n            raise Exception(\"yui-compressor is not installed.\")\n            return False\n\n    return runinplace(r'{} --nomunge %1 -o %2'.format(yuicompressor), infile)\n\n\ndef closure_compiler(infile):\n    return runinplace(r'closure-compiler --warning_level QUIET --js %1 --js_output_file %2', infile)\n\n\ndef optipng(infile):\n    return runinplace(r\"optipng -preserve -o2 -quiet %1\", infile)\n\n\ndef jpegoptim(infile):\n    return runinplace(r\"jpegoptim -p --strip-all -q %1\", infile)\n\n\n@apply_to_text_file\ndef minify_lines(data):\n    datalines = data.splitlines()\n    datalines = [line.lstrip() for line in datalines if not (line.strip() == \"\")]\n    return \"\\n\".join(datalines)\n\n\n@apply_to_text_file\ndef typogrify(data):\n    if typo is None:\n        req_missing(['typogrify'], 'use the typogrify filter')\n\n    data = typo.amp(data)\n    data = typo.widont(data)\n    data = typo.smartypants(data)\n    # Disabled because of typogrify bug where it breaks <title>\n    # data = typo.caps(data)\n    data = typo.initial_quotes(data)\n    return data\n\n\n@apply_to_text_file\ndef php_template_injection(data):\n    import re\n    template = re.search('<\\!-- __NIKOLA_PHP_TEMPLATE_INJECTION source\\:(.*) checksum\\:(.*)__ -->', data)\n    if template:\n        source = template.group(1)\n        with io.open(source, \"r\", encoding=\"utf-8\") as in_file:\n            phpdata = in_file.read()\n        _META_SEPARATOR = '(' + os.linesep * 2 + '|' + ('\\n' * 2) + '|' + (\"\\r\\n\" * 2) + ')'\n        phpdata = re.split(_META_SEPARATOR, phpdata, maxsplit=1)[-1]\n        phpdata = re.sub(template.group(0), phpdata, data)\n\n    return phpdata\n", "path": "nikola/filters.py"}], "after_files": [{"content": "# -*- coding: utf-8 -*-\n\n# Copyright \u00a9 2012-2014 Roberto Alsina and others.\n\n# Permission is hereby granted, free of charge, to any\n# person obtaining a copy of this software and associated\n# documentation files (the \"Software\"), to deal in the\n# Software without restriction, including without limitation\n# the rights to use, copy, modify, merge, publish,\n# distribute, sublicense, and/or sell copies of the\n# Software, and to permit persons to whom the Software is\n# furnished to do so, subject to the following conditions:\n#\n# The above copyright notice and this permission notice\n# shall be included in all copies or substantial portions of\n# the Software.\n#\n# THE SOFTWARE IS PROVIDED \"AS IS\", WITHOUT WARRANTY OF ANY\n# KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE\n# WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR\n# PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS\n# OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR\n# OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR\n# OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE\n# SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.\n\n\"\"\"Utility functions to help you run filters on files.\"\"\"\n\nfrom .utils import req_missing\nfrom functools import wraps\nimport os\nimport io\nimport shutil\nimport subprocess\nimport tempfile\nimport shlex\n\ntry:\n    import typogrify.filters as typo\nexcept ImportError:\n    typo = None  # NOQA\n\n\ndef apply_to_binary_file(f):\n    \"\"\"Take a function f that transforms a data argument, and returns\n    a function that takes a filename and applies f to the contents,\n    in place.  Reads files in binary mode.\"\"\"\n    @wraps(f)\n    def f_in_file(fname):\n        with open(fname, 'rb') as inf:\n            data = inf.read()\n        data = f(data)\n        with open(fname, 'wb+') as outf:\n            outf.write(data)\n\n    return f_in_file\n\n\ndef apply_to_text_file(f):\n    \"\"\"Take a function f that transforms a data argument, and returns\n    a function that takes a filename and applies f to the contents,\n    in place.  Reads files in UTF-8.\"\"\"\n    @wraps(f)\n    def f_in_file(fname):\n        with io.open(fname, 'r', encoding='utf-8') as inf:\n            data = inf.read()\n        data = f(data)\n        with io.open(fname, 'w+', encoding='utf-8') as outf:\n            outf.write(data)\n\n    return f_in_file\n\n\ndef list_replace(the_list, find, replacement):\n    \"Replace all occurrences of ``find`` with ``replacement`` in ``the_list``\"\n    for i, v in enumerate(the_list):\n        if v == find:\n            the_list[i] = replacement\n\n\ndef runinplace(command, infile):\n    \"\"\"Run a command in-place on a file.\n\n    command is a string of the form: \"commandname %1 %2\" and\n    it will be execed with infile as %1 and a temporary file\n    as %2. Then, that temporary file will be moved over %1.\n\n    Example usage:\n\n    runinplace(\"yui-compressor %1 -o %2\", \"myfile.css\")\n\n    That will replace myfile.css with a minified version.\n\n    You can also supply command as a list.\n    \"\"\"\n\n    if not isinstance(command, list):\n        command = shlex.split(command)\n\n    tmpdir = None\n\n    if \"%2\" in command:\n        tmpdir = tempfile.mkdtemp(prefix=\"nikola\")\n        tmpfname = os.path.join(tmpdir, os.path.basename(infile))\n\n    try:\n        list_replace(command, \"%1\", infile)\n        if tmpdir:\n            list_replace(command, \"%2\", tmpfname)\n\n        subprocess.check_call(command)\n\n        if tmpdir:\n            shutil.move(tmpfname, infile)\n    finally:\n        if tmpdir:\n            shutil.rmtree(tmpdir)\n\n\ndef yui_compressor(infile):\n    yuicompressor = False\n    try:\n        subprocess.call('yui-compressor', stdout=open(os.devnull, 'w'), stderr=open(os.devnull, 'w'))\n        yuicompressor = 'yui-compressor'\n    except Exception:\n        pass\n    if not yuicompressor:\n        try:\n            subprocess.call('yuicompressor', stdout=open(os.devnull, 'w'), stderr=open(os.devnull, 'w'))\n            yuicompressor = 'yuicompressor'\n        except:\n            raise Exception(\"yui-compressor is not installed.\")\n            return False\n\n    return runinplace(r'{} --nomunge %1 -o %2'.format(yuicompressor), infile)\n\n\ndef closure_compiler(infile):\n    return runinplace(r'closure-compiler --warning_level QUIET --js %1 --js_output_file %2', infile)\n\n\ndef optipng(infile):\n    return runinplace(r\"optipng -preserve -o2 -quiet %1\", infile)\n\n\ndef jpegoptim(infile):\n    return runinplace(r\"jpegoptim -p --strip-all -q %1\", infile)\n\n\n@apply_to_text_file\ndef minify_lines(data):\n    datalines = data.splitlines()\n    datalines = [line.lstrip() for line in datalines if not (line.strip() == \"\")]\n    return \"\\n\".join(datalines)\n\n\n@apply_to_text_file\ndef typogrify(data):\n    if typo is None:\n        req_missing(['typogrify'], 'use the typogrify filter')\n\n    data = typo.amp(data)\n    data = typo.widont(data)\n    data = typo.smartypants(data)\n    # Disabled because of typogrify bug where it breaks <title>\n    # data = typo.caps(data)\n    data = typo.initial_quotes(data)\n    return data\n\n\n@apply_to_text_file\ndef php_template_injection(data):\n    import re\n    template = re.search('<\\!-- __NIKOLA_PHP_TEMPLATE_INJECTION source\\:(.*) checksum\\:(.*)__ -->', data)\n    if template:\n        source = template.group(1)\n        with io.open(source, \"r\", encoding=\"utf-8\") as in_file:\n            phpdata = in_file.read()\n        _META_SEPARATOR = '(' + os.linesep * 2 + '|' + ('\\n' * 2) + '|' + (\"\\r\\n\" * 2) + ')'\n        phpdata = re.split(_META_SEPARATOR, phpdata, maxsplit=1)[-1]\n        phpdata = re.sub(template.group(0), phpdata, data)\n        return phpdata\n    else:\n        return data\n", "path": "nikola/filters.py"}]}