Python2/3 compatibility - StringIO

[serge-sans-paille]

Summary

StringIO

[michaelplatings]

Can you comment on whether the differences between StringIO and io.StringIO might be significant? https://stackoverflow.com/a/49795277

[joerg]

bindings/python/tests/cindex/test_translation_unit.py

96 ↗

(On Diff #176337)

Move it to the import list at the top of the file.

tools/scan-view/share/ScanView.py

110 ↗

(On Diff #176337)

This and the following cases want byte IO, don't they?

[serge-sans-paille]

StringIO is obsoleted in python3, replaced by io.StringIO.
Yet io.StringIO only handles unicode string, while StringIO.StringIO only handles str, i.e. bytes.

[serge-sans-paille]

tools/scan-view/share/ScanView.py

110 ↗

(On Diff #176337)

Yeah, it's probably safer. It really depends on the content of `e`. It also appears that Python 2.7 supports io.BytesIO, so I'd rather use that uniformly.

[serge-sans-paille]

Use BytesIO as a repalcement... it more closely matches StringIO.StringIO

[serge-sans-paille]

Update StringIO conversion after more testing.

[michaelplatings]

tools/scan-view/share/ScanView.py

115 ↗

(On Diff #176568)

With Python 2 this fails with:
TypeError: unicode argument expected, got 'str'

[michaelplatings]

bindings/python/tests/cindex/test_translation_unit.py

97 ↗

(On Diff #179060)

May as well make this >= 3

tools/clang-format/clang-format-diff.py

32 ↗

(On Diff #179060)

May as well make this >= 3

tools/scan-view/share/ScanView.py

17 ↗

(On Diff #179060)

May as well make this >= 3

288 ↗

(On Diff #179060)

Why is this necessary? send_string returns a BytesIO object so why create a different one?

[michaelplatings]

LGTM

cfe/trunk/bindings/python/tests/cindex/test_translation_unit.py

 import os
 from clang.cindex import Config
 if 'CLANG_LIBRARY_PATH' in os.environ:
     Config.set_library_path(os.environ['CLANG_LIBRARY_PATH'])
 
 from contextlib import contextmanager
 import gc
 import os
+import sys
 import tempfile
 import unittest
 
 from clang.cindex import CursorKind
 from clang.cindex import Cursor
 from clang.cindex import File
 from clang.cindex import Index
 from clang.cindex import SourceLocation

 #define SOME_DEFINE y
 """)
                 ])
         spellings = [c.spelling for c in tu.cursor.get_children()]
         self.assertEqual(spellings[-2], 'x')
         self.assertEqual(spellings[-1], 'y')
 
     def test_unsaved_files_2(self):
-        try:
-            from StringIO import StringIO
-        except:
+        if sys.version_info.major >= 3:
             from io import StringIO
+        else:
+            from io import BytesIO as StringIO
         tu = TranslationUnit.from_source('fake.c', unsaved_files = [
                 ('fake.c', StringIO('int x;'))])
         spellings = [c.spelling for c in tu.cursor.get_children()]
         self.assertEqual(spellings[-1], 'x')
 
     @skip_if_no_fspath
     def test_from_source_accepts_pathlike(self):
         tu = TranslationUnit.from_source(str_to_path('fake.c'), ['-Iincludes'], unsaved_files = [

cfe/trunk/tools/clang-format/clang-format-diff.py

 """
 from __future__ import absolute_import, division, print_function
 
 import argparse
 import difflib
 import re
 import subprocess
 import sys
-try:
-  from StringIO import StringIO
-except ImportError:
+
+if sys.version_info.major >= 3:
     from io import StringIO
+else:
+    from io import BytesIO as StringIO
 
 
 def main():
   parser = argparse.ArgumentParser(description=
                                    'Reformat changed lines in diff. Without -i '
                                    'option just output the diff that would be '
                                    'introduced.')
   parser.add_argument('-i', action='store_true', default=False,

cfe/trunk/tools/scan-view/share/ScanView.py

 from __future__ import print_function
 try:
     from http.server import HTTPServer, SimpleHTTPRequestHandler
 except ImportError:
     from BaseHTTPServer import HTTPServer
     from SimpleHTTPServer import SimpleHTTPRequestHandler
 import os
 import sys
 try:
     from urlparse import urlparse
     from urllib import unquote
 except ImportError:
     from urllib.parse import urlparse, unquote
 
 import posixpath
-import StringIO
+
+if sys.version_info.major >= 3:
+    from io import StringIO, BytesIO
+else:
+    from io import BytesIO, BytesIO as StringIO
+
 import re
 import shutil
 import threading
 import time
 import socket
 import itertools
 
 import Reporter
def run(self):
             self.status = self.reporter.fileReport(self.report, self.parameters)
             self.success = True
             time.sleep(3)
             if self.server.options.debug:
                 print("%s: SERVER: submission complete."%(sys.argv[0],), file=sys.stderr)
         except Reporter.ReportFailure as e:
             self.status = e.value
         except Exception as e:
-            s = StringIO.StringIO()
+            s = StringIO()
             import traceback
             print('<b>Unhandled Exception</b><br><pre>', file=s)
             traceback.print_exc(file=s)
             print('</pre>', file=s)
             self.status = s.getvalue()
 
 class ScanViewServer(HTTPServer):
     def __init__(self, address, handler, root, reporters, options):
def load_crashes(self):
             fieldData = item.group(1)
             fields = dict([i.groups() for i in 
                            kReportCrashEntryKeyValueRE.finditer(fieldData)])
             problems.append(fields)
         return problems
 
     def handle_exception(self, exc):
         import traceback
-        s = StringIO.StringIO()
+        s = StringIO()
         print("INTERNAL ERROR\n", file=s)
         traceback.print_exc(file=s)
         f = self.send_string(s.getvalue(), 'text/plain')
         if f:
             self.copyfile(f, self.wfile)
             f.close()        
             
     def get_scalar_field(self, name):
def send_file(self, f, ctype):
         self.send_header("Content-type", ctype)
         fs = os.fstat(f.fileno())
         self.send_header("Content-Length", str(fs[6]))
         self.send_header("Last-Modified", self.date_time_string(fs.st_mtime))
         self.end_headers()
         return f
 
     def send_string(self, s, ctype='text/html', headers=True, mtime=None):
+        encoded_s = s.encode()
         if headers:
             self.send_response(200)
             self.send_header("Content-type", ctype)
-            self.send_header("Content-Length", str(len(s)))
+            self.send_header("Content-Length", str(len(encoded_s)))
             if mtime is None:
                 mtime = self.dynamic_mtime
             self.send_header("Last-Modified", self.date_time_string(mtime))
             self.end_headers()
-        return StringIO.StringIO(s)
+        return BytesIO(encoded_s)
 
     def send_patched_file(self, path, ctype):
         # Allow a very limited set of variables. This is pretty gross.
         variables = {}
         variables['report'] = ''
         m = kReportFileRE.match(path)
         if m:
             variables['report'] = m.group(2)