Fixes, including hang bug in readline

Author: willmcgugan@gmail.com

CHANGES.txt

@@ -79,7 +79,7 @@
     * Removed obsolete module fs.objectree; use fs.path.PathMap instead.
     * Added setcontents_async method to base
     * Added `appdirfs` module to abstract per-user application directories
-    
+
 0.5:
 
     * Ported to Python 3.X
@@ -88,3 +88,8 @@
     * Added sqlitefs to fs.contrib, contributed by Nitin Bhide
     * Added archivefs to fs.contrib, contributed by btimby
     * Added some polish to fstree command and unicode box lines rather than ascii art
+
+0.5:
+
+    * Fixed a hang bug in readline
+

fs/commands/runner.py

@@ -258,7 +258,7 @@ def output_table(self, table, col_process=None, verbose=False):
 
     def error(self, *msgs):
         for msg in msgs:
-            self.error_file.write('%s: %s' % (self.name, self.text_encode(msg)))
+            self.error_file.write("{}: {}".format(self.name, msg).encode(self.encoding))
 
     def get_optparse(self):
         optparse = OptionParser(usage=self.usage, version=self.version)

fs/filelike.py

@@ -494,7 +494,7 @@ def readline(self,size=-1):
             nextBit = self.read(self._bufsize)
             bits.append(nextBit)
             sizeSoFar += len(nextBit)
-            if nextBit == b(""):
+            if not nextBit:
                 break
             if size > 0 and sizeSoFar >= size:
                 break

fs/ftpfs.py

@@ -804,40 +804,15 @@ def close(self):
                 pass
         self.closed = True
 
-    def __iter__(self):
-        return self.next()
-
-    @synchronize
     def next(self):
-        """ Line iterator
+        return self.readline()
+
+    def readline(self, size=None):
+        return next(iotools.line_iterator(self, size))
+
+    def __iter__(self):
+        return iotools.line_iterator(self)
 
-        This isn't terribly efficient. It would probably be better to do
-        a read followed by splitlines.
-        """
-        endings = b('\r\n')
-        chars = []
-        append = chars.append
-        read = self.read
-        join = b('').join
-        while True:
-            char = read(1)
-            if not char:
-                if chars:
-                    yield join(chars)
-                break
-            append(char)
-            if char in endings:
-                line = join(chars)
-                del chars[:]
-                c = read(1)
-                if not char:
-                    yield line
-                    break
-                if c in endings and c != char:
-                    yield line + c
-                else:
-                    yield line
-                    append(c)
 
 def ftperrors(f):
     @wraps(f)

fs/iotools.py

@@ -211,6 +211,30 @@ def copy_file_to_fs(f, fs, path, encoding=None, errors=None, progress_callback=N
     return bytes_written
 
 
+def line_iterator(f, size=None):
+    """A not terribly efficient char by char line iterator"""
+    read = f.read
+    line = []
+    append = line.append
+    c = 1
+    if size is None or size < 0:
+        while c:
+            c = read(1)
+            if c:
+                append(c)
+            if c in (b'\n', b''):
+                yield b''.join(line)
+                del line[:]
+    else:
+        while c:
+            c = read(1)
+            if c:
+                append(c)
+            if c in (b'\n', b'') or len(line) >= size:
+                yield b''.join(line)
+                del line[:]
+
+
 if __name__ == "__main__":
     print("Reading a binary file")
     bin_file = open('tests/data/UTF-8-demo.txt', 'rb')

fs/path.py

@@ -376,7 +376,7 @@ def isprefix(path1, path2):
 
 
 def forcedir(path):
-    """Ensure the path ends with a trailing /
+    """Ensure the path ends with a trailing formward slash
 
     :param path: An FS path
 

fs/tests/__init__.py

@@ -147,6 +147,13 @@ def test_createfile(self):
         self.fs.createfile("test.txt", wipe=True)
         self.assertEqual(self.fs.getcontents("test.txt", "rb"), b(''))
 
+    def test_readline(self):
+        text = b"Hello\nWorld\n"
+        self.fs.setcontents('a.txt', text)
+        with self.fs.open('a.txt', 'rb') as f:
+            line = f.readline()
+        self.assertEqual(line, b"Hello\n")
+
     def test_setcontents(self):
         #  setcontents() should accept both a string...
         self.fs.setcontents("hello", b("world"))