File opened without the
with statement PTC-W0010
Anti-pattern
Critical
3 months ago
—
3 months old
Use the
with statement to open a file20 "tmax": row[3],
21 "tmin": row[4],
22 }
23o = open("kbs_century.txt", "w")24
25for year in range(1951, 2013):
26 for col in ["prec", "tmin", "tmax"]:Use the
with statement to open a file105 worksheet.freeze_panes(3, 0)
106
107 fn = ",".join(stations)
108 res = open("/tmp/ss.xlsx", "rb").read()109 os.unlink("/tmp/ss.xlsx")
110 return res, fn
111Use the
with statement to open a file180 df.to_excel(writer, sheet_name="Data", index=False)
181 worksheet = writer.sheets["Data"]
182 worksheet.freeze_panes(3, 0)
183 payload = open("/tmp/ss.xlsx", "rb").read()184 os.unlink("/tmp/ss.xlsx")
185 return [payload]
186Use the
with statement to open a file109 df.to_excel(writer, sheet_name="Data", index=False)
110 worksheet = writer.sheets["Data"]
111 worksheet.freeze_panes(3, 0)
112 payload = open("/tmp/ss.xlsx", "rb").read()113 os.unlink("/tmp/ss.xlsx")
114 return [payload]
115Use the
with statement to open a file171 df.to_excel(writer, sheet_name="Data", index=False)
172 worksheet = writer.sheets["Data"]
173 worksheet.freeze_panes(3, 0)
174 payload = open("/tmp/ss.xlsx", "rb").read()175 os.unlink("/tmp/ss.xlsx")
176 return [payload]
177
Description
Opening a file using with statement is preferred as function open implements the context manager protocol that releases the resource when it is outside of the with block. Not doing so requires you to manually release the resource.
Bad practice
f = open('/tmp/.deepsource.toml', 'w')
f.write("config file.")
# No `f.close()` statement: file may remain unaccessible
Preferred:
with open('/tmp/.deepsource.toml', 'w') as f:
f.write("config file.")