Files
micropython/tests/basics/io_buffered_writer.py
Jeff Epler b6b7d64bd9 py/modio: Fix the case where write fails in BufferedWriter.flush.
Previously, there was no test coverage of the "write failed" path.  In
fact, the assertion would fire instead of gracefully raising a Python
exception.

Slightly re-organize the code to place the assertion later.  Add a test
case which exercises all paths, and update the expected output.

Signed-off-by: Jeff Epler <jepler@gmail.com>
2025-06-17 10:15:59 +10:00

55 lines
1023 B
Python

import io
try:
io.BytesIO
io.BufferedWriter
except AttributeError:
print('SKIP')
raise SystemExit
bts = io.BytesIO()
buf = io.BufferedWriter(bts, 8)
buf.write(b"foobar")
print(bts.getvalue())
buf.write(b"foobar")
# CPython has different flushing policy, so value below is different
print(bts.getvalue())
buf.flush()
print(bts.getvalue())
buf.flush()
print(bts.getvalue())
# special case when alloc is a factor of total buffer length
bts = io.BytesIO()
buf = io.BufferedWriter(bts, 1)
buf.write(b"foo")
print(bts.getvalue())
# hashing a BufferedWriter
print(type(hash(buf)))
# Test failing flush()
class MyIO(io.IOBase):
def __init__(self):
self.count = 0
def write(self, buf):
self.count += 1
if self.count < 3:
return None
print("writing", buf)
return len(buf)
buf = io.BufferedWriter(MyIO(), 8)
buf.write(b"foobar")
for _ in range(4):
try:
buf.flush()
print("flushed")
except OSError:
print("OSError")