runtime: add support for and implement stdin

integration/tests/file_buffered_read.py

@@ -0,0 +1,44 @@
+# Regression test: BufferedReader.read1(n)/read(n) must return at most n
+# bytes and never None. Previously the buffered fast path returned every
+# buffered byte regardless of n, or None when fewer than n bytes were
+# buffered.
+
+# Run with cwd == integration/ (as the integration runner does).
+DATA = "tests/file_readline_data.txt" # b"a\nbb\nccc"
+
+# 1. read1 returns at most n bytes; "" at EOF.
+f = open(DATA, "rb")
+assert f.read1(3) == b"a\nb"
+assert f.read1(0) == b""
+assert f.read1(100) == b"b\nccc"
+assert f.read1(4) == b""
+assert f.read1() == b""
+f.close()
+
+# 2. read(n) returns exactly n bytes until the stream runs out.
+g = open(DATA, "rb")
+assert g.read(2) == b"a\n"
+assert g.read(100) == b"bb\nccc"
+assert g.read(1) == b""
+g.close()
+
+# 3. read() with no argument reads everything.
+h = open(DATA, "rb")
+assert h.read() == b"a\nbb\nccc"
+assert h.read() == b""
+h.close()
+
+# 4. readinto fills a writable buffer and returns the byte count; read-only
+# buffers (bytes) must be rejected instead of silently written to.
+i = open(DATA, "rb")
+ba = bytearray(b"xyz")
+assert i.readinto(ba) == 3
+assert ba == bytearray(b"a\nb")
+try:
+ i.readinto(b"xxxx")
+ assert False, "readinto(bytes) must raise TypeError"
+except TypeError:
+ pass
+i.close()
+
+print("file_buffered_read: ok")

integration/tests/file_readline.py

@@ -0,0 +1,85 @@
+# Regression test: TextIOWrapper.readline must return one line at a time
+# (including the line ending), honour the size limit, keep lines that span
+# the 8192-byte read chunks intact, and return "" at EOF. Previously a single
+# call concatenated lines, dropped data, or crashed on uneven line lengths.
+
+# Run with cwd == integration/ (as the integration runner does).
+DATA = "tests/file_readline_data.txt" # b"a\nbb\nccc" (no trailing newline)
+DATA_CRLF = "tests/file_readline_data_crlf.txt" # b"one\r\ntwo\r\n"
+DATA_LONG = "tests/file_readline_data_long.txt" # b"x" * 9000 + b"\ntail\n"
+DATA_STRADDLE = "tests/file_readline_data_straddle.txt" # b"x" * 8191 + b"\r\ntail\r\n"
+DATA_CR_TAIL = "tests/file_readline_data_cr_tail.txt" # b"a\nb\r"
+DATA_CHUNK_END = "tests/file_readline_data_chunk_end.txt" # b"x" * 8191 + b"\ntail\n"
+
+# 1. one line per call, trailing newline included, "" at EOF (and stays "").
+f = open(DATA, "r")
+assert f.readline() == "a\n"
+assert f.readline() == "bb\n"
+assert f.readline() == "ccc"
+assert f.readline() == ""
+assert f.readline() == ""
+
+# 2. size limit: at most `limit` characters, the rest stays buffered.
+g = open(DATA, "r")
+assert g.readline(1) == "a"
+assert g.readline(0) == ""
+assert g.readline(100) == "\n"
+assert g.readline(2) == "bb"
+assert g.readline() == "\n"
+assert g.readline() == "ccc"
+
+# 3. \r\n is consumed as a single line ending (no spurious empty line).
+# TODO: with newline=None CPython translates the terminator to "\n"; the
+# decoder is not implemented yet, so the raw ending is returned for now.
+h = open(DATA_CRLF, "r")
+assert h.readline() == "one\r\n"
+assert h.readline() == "two\r\n"
+assert h.readline() == ""
+
+# 4. a line longer than the 8192-byte read chunk is returned whole.
+i = open(DATA_LONG, "r")
+line = i.readline()
+assert len(line) == 9001, len(line)
+assert i.readline() == "tail\n"
+assert i.readline() == ""
+
+# 5. readlines returns the same split.
+j = open(DATA, "r")
+assert j.readlines() == ["a\n", "bb\n", "ccc"]
+
+# 6. a \r\n split across the 8192-byte chunk boundary stays one line ending
+# (the first chunk ends with the \r, the \n arrives with the next chunk).
+k = open(DATA_STRADDLE, "r")
+line = k.readline()
+assert len(line) == 8193, len(line)
+assert line == "x" * 8191 + "\r\n"
+assert k.readline() == "tail\r\n"
+assert k.readline() == ""
+
+# 7. a \r\n straddling the size limit: the \r fits within the limit, the \n
+# stays buffered and becomes its own line on the next call (CPython clamps
+# the found line to size and pushes the remainder back).
+m = open(DATA_CRLF, "r")
+assert m.readline(4) == "one\r"
+assert m.readline() == "\n"
+assert m.readline() == "two\r\n"
+assert m.readline() == ""
+
+# 8. an unresolved trailing \r must not stop an earlier complete line from
+# being returned (on a blocking stream the read-ahead would stall), and a
+# lone \r at EOF terminates the final line.
+n = open(DATA_CR_TAIL, "r")
+assert n.readline() == "a\n"
+assert n.readline() == "b\r"
+assert n.readline() == ""
+
+# 9. readlines keeps reading past a delimiter that lands exactly on the chunk
+# boundary and drains the buffer mid-stream (the first line fills the whole
+# 8192-byte chunk).
+o = open(DATA_CHUNK_END, "r")
+assert o.readlines() == ["x" * 8191 + "\n", "tail\n"]
+p = open(DATA_CHUNK_END, "r")
+assert p.readline() == "x" * 8191 + "\n"
+assert p.readlines() == ["tail\n"]
+
+print("file_readline: ok")

integration/tests/file_readline_data.txt

@@ -0,0 +1,3 @@
+a
+bb
+ccc

integration/tests/file_readline_data_chunk_end.txt

@@ -0,0 +1,2 @@
+xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx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+tail

integration/tests/file_readline_data_cr_tail.txt

@@ -0,0 +1,2 @@
+a
+b

integration/tests/file_readline_data_crlf.txt

@@ -0,0 +1,2 @@
+one
+two

integration/tests/file_buffered_read.py

@@ -0,0 +1,44 @@
+# Regression test: BufferedReader.read1(n)/read(n) must return at most n
+# bytes and never None. Previously the buffered fast path returned every
+# buffered byte regardless of n, or None when fewer than n bytes were
+# buffered.
+
+# Run with cwd == integration/ (as the integration runner does).
+DATA = "tests/file_readline_data.txt" # b"a\nbb\nccc"
+
+# 1. read1 returns at most n bytes; "" at EOF.
+f = open(DATA, "rb")
+assert f.read1(3) == b"a\nb"
+assert f.read1(0) == b""
+assert f.read1(100) == b"b\nccc"
+assert f.read1(4) == b""
+assert f.read1() == b""
+f.close()
+
+# 2. read(n) returns exactly n bytes until the stream runs out.
+g = open(DATA, "rb")
+assert g.read(2) == b"a\n"
+assert g.read(100) == b"bb\nccc"
+assert g.read(1) == b""
+g.close()
+
+# 3. read() with no argument reads everything.
+h = open(DATA, "rb")
+assert h.read() == b"a\nbb\nccc"
+assert h.read() == b""
+h.close()
+
+# 4. readinto fills a writable buffer and returns the byte count; read-only
+# buffers (bytes) must be rejected instead of silently written to.
+i = open(DATA, "rb")
+ba = bytearray(b"xyz")
+assert i.readinto(ba) == 3
+assert ba == bytearray(b"a\nb")
+try:
+ i.readinto(b"xxxx")
+ assert False, "readinto(bytes) must raise TypeError"
+except TypeError:
+ pass
+i.close()
+
+print("file_buffered_read: ok")

integration/tests/file_readline.py

@@ -0,0 +1,85 @@
+# Regression test: TextIOWrapper.readline must return one line at a time
+# (including the line ending), honour the size limit, keep lines that span
+# the 8192-byte read chunks intact, and return "" at EOF. Previously a single
+# call concatenated lines, dropped data, or crashed on uneven line lengths.
+
+# Run with cwd == integration/ (as the integration runner does).
+DATA = "tests/file_readline_data.txt" # b"a\nbb\nccc" (no trailing newline)
+DATA_CRLF = "tests/file_readline_data_crlf.txt" # b"one\r\ntwo\r\n"
+DATA_LONG = "tests/file_readline_data_long.txt" # b"x" * 9000 + b"\ntail\n"
+DATA_STRADDLE = "tests/file_readline_data_straddle.txt" # b"x" * 8191 + b"\r\ntail\r\n"
+DATA_CR_TAIL = "tests/file_readline_data_cr_tail.txt" # b"a\nb\r"
+DATA_CHUNK_END = "tests/file_readline_data_chunk_end.txt" # b"x" * 8191 + b"\ntail\n"
+
+# 1. one line per call, trailing newline included, "" at EOF (and stays "").
+f = open(DATA, "r")
+assert f.readline() == "a\n"
+assert f.readline() == "bb\n"
+assert f.readline() == "ccc"
+assert f.readline() == ""
+assert f.readline() == ""
+
+# 2. size limit: at most `limit` characters, the rest stays buffered.
+g = open(DATA, "r")
+assert g.readline(1) == "a"
+assert g.readline(0) == ""
+assert g.readline(100) == "\n"
+assert g.readline(2) == "bb"
+assert g.readline() == "\n"
+assert g.readline() == "ccc"
+
+# 3. \r\n is consumed as a single line ending (no spurious empty line).
+# TODO: with newline=None CPython translates the terminator to "\n"; the
+# decoder is not implemented yet, so the raw ending is returned for now.
+h = open(DATA_CRLF, "r")
+assert h.readline() == "one\r\n"
+assert h.readline() == "two\r\n"
+assert h.readline() == ""
+
+# 4. a line longer than the 8192-byte read chunk is returned whole.
+i = open(DATA_LONG, "r")
+line = i.readline()
+assert len(line) == 9001, len(line)
+assert i.readline() == "tail\n"
+assert i.readline() == ""
+
+# 5. readlines returns the same split.
+j = open(DATA, "r")
+assert j.readlines() == ["a\n", "bb\n", "ccc"]
+
+# 6. a \r\n split across the 8192-byte chunk boundary stays one line ending
+# (the first chunk ends with the \r, the \n arrives with the next chunk).
+k = open(DATA_STRADDLE, "r")
+line = k.readline()
+assert len(line) == 8193, len(line)
+assert line == "x" * 8191 + "\r\n"
+assert k.readline() == "tail\r\n"
+assert k.readline() == ""
+
+# 7. a \r\n straddling the size limit: the \r fits within the limit, the \n
+# stays buffered and becomes its own line on the next call (CPython clamps
+# the found line to size and pushes the remainder back).
+m = open(DATA_CRLF, "r")
+assert m.readline(4) == "one\r"
+assert m.readline() == "\n"
+assert m.readline() == "two\r\n"
+assert m.readline() == ""
+
+# 8. an unresolved trailing \r must not stop an earlier complete line from
+# being returned (on a blocking stream the read-ahead would stall), and a
+# lone \r at EOF terminates the final line.
+n = open(DATA_CR_TAIL, "r")
+assert n.readline() == "a\n"
+assert n.readline() == "b\r"
+assert n.readline() == ""
+
+# 9. readlines keeps reading past a delimiter that lands exactly on the chunk
+# boundary and drains the buffer mid-stream (the first line fills the whole
+# 8192-byte chunk).
+o = open(DATA_CHUNK_END, "r")
+assert o.readlines() == ["x" * 8191 + "\n", "tail\n"]
+p = open(DATA_CHUNK_END, "r")
+assert p.readline() == "x" * 8191 + "\n"
+assert p.readlines() == ["tail\n"]
+
+print("file_readline: ok")

integration/tests/file_readline_data.txt

@@ -0,0 +1,3 @@
+a
+bb
+ccc

integration/tests/file_readline_data_chunk_end.txt

@@ -0,0 +1,2 @@
+xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx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+tail

integration/tests/file_readline_data_cr_tail.txt

@@ -0,0 +1,2 @@
+a
+b

integration/tests/file_readline_data_crlf.txt

@@ -0,0 +1,2 @@
+one
+two

integration/tests/file_buffered_read.py

@@ -0,0 +1,44 @@
+# Regression test: BufferedReader.read1(n)/read(n) must return at most n
+# bytes and never None. Previously the buffered fast path returned every
+# buffered byte regardless of n, or None when fewer than n bytes were
+# buffered.
+
+# Run with cwd == integration/ (as the integration runner does).
+DATA = "tests/file_readline_data.txt" # b"a\nbb\nccc"
+
+# 1. read1 returns at most n bytes; "" at EOF.
+f = open(DATA, "rb")
+assert f.read1(3) == b"a\nb"
+assert f.read1(0) == b""
+assert f.read1(100) == b"b\nccc"
+assert f.read1(4) == b""
+assert f.read1() == b""
+f.close()
+
+# 2. read(n) returns exactly n bytes until the stream runs out.
+g = open(DATA, "rb")
+assert g.read(2) == b"a\n"
+assert g.read(100) == b"bb\nccc"
+assert g.read(1) == b""
+g.close()
+
+# 3. read() with no argument reads everything.
+h = open(DATA, "rb")
+assert h.read() == b"a\nbb\nccc"
+assert h.read() == b""
+h.close()
+
+# 4. readinto fills a writable buffer and returns the byte count; read-only
+# buffers (bytes) must be rejected instead of silently written to.
+i = open(DATA, "rb")
+ba = bytearray(b"xyz")
+assert i.readinto(ba) == 3
+assert ba == bytearray(b"a\nb")
+try:
+ i.readinto(b"xxxx")
+ assert False, "readinto(bytes) must raise TypeError"
+except TypeError:
+ pass
+i.close()
+
+print("file_buffered_read: ok")

integration/tests/file_readline.py

@@ -0,0 +1,85 @@
+# Regression test: TextIOWrapper.readline must return one line at a time
+# (including the line ending), honour the size limit, keep lines that span
+# the 8192-byte read chunks intact, and return "" at EOF. Previously a single
+# call concatenated lines, dropped data, or crashed on uneven line lengths.
+
+# Run with cwd == integration/ (as the integration runner does).
+DATA = "tests/file_readline_data.txt" # b"a\nbb\nccc" (no trailing newline)
+DATA_CRLF = "tests/file_readline_data_crlf.txt" # b"one\r\ntwo\r\n"
+DATA_LONG = "tests/file_readline_data_long.txt" # b"x" * 9000 + b"\ntail\n"
+DATA_STRADDLE = "tests/file_readline_data_straddle.txt" # b"x" * 8191 + b"\r\ntail\r\n"
+DATA_CR_TAIL = "tests/file_readline_data_cr_tail.txt" # b"a\nb\r"
+DATA_CHUNK_END = "tests/file_readline_data_chunk_end.txt" # b"x" * 8191 + b"\ntail\n"
+
+# 1. one line per call, trailing newline included, "" at EOF (and stays "").
+f = open(DATA, "r")
+assert f.readline() == "a\n"
+assert f.readline() == "bb\n"
+assert f.readline() == "ccc"
+assert f.readline() == ""
+assert f.readline() == ""
+
+# 2. size limit: at most `limit` characters, the rest stays buffered.
+g = open(DATA, "r")
+assert g.readline(1) == "a"
+assert g.readline(0) == ""
+assert g.readline(100) == "\n"
+assert g.readline(2) == "bb"
+assert g.readline() == "\n"
+assert g.readline() == "ccc"
+
+# 3. \r\n is consumed as a single line ending (no spurious empty line).
+# TODO: with newline=None CPython translates the terminator to "\n"; the
+# decoder is not implemented yet, so the raw ending is returned for now.
+h = open(DATA_CRLF, "r")
+assert h.readline() == "one\r\n"
+assert h.readline() == "two\r\n"
+assert h.readline() == ""
+
+# 4. a line longer than the 8192-byte read chunk is returned whole.
+i = open(DATA_LONG, "r")
+line = i.readline()
+assert len(line) == 9001, len(line)
+assert i.readline() == "tail\n"
+assert i.readline() == ""
+
+# 5. readlines returns the same split.
+j = open(DATA, "r")
+assert j.readlines() == ["a\n", "bb\n", "ccc"]
+
+# 6. a \r\n split across the 8192-byte chunk boundary stays one line ending
+# (the first chunk ends with the \r, the \n arrives with the next chunk).
+k = open(DATA_STRADDLE, "r")
+line = k.readline()
+assert len(line) == 8193, len(line)
+assert line == "x" * 8191 + "\r\n"
+assert k.readline() == "tail\r\n"
+assert k.readline() == ""
+
+# 7. a \r\n straddling the size limit: the \r fits within the limit, the \n
+# stays buffered and becomes its own line on the next call (CPython clamps
+# the found line to size and pushes the remainder back).
+m = open(DATA_CRLF, "r")
+assert m.readline(4) == "one\r"
+assert m.readline() == "\n"
+assert m.readline() == "two\r\n"
+assert m.readline() == ""
+
+# 8. an unresolved trailing \r must not stop an earlier complete line from
+# being returned (on a blocking stream the read-ahead would stall), and a
+# lone \r at EOF terminates the final line.
+n = open(DATA_CR_TAIL, "r")
+assert n.readline() == "a\n"
+assert n.readline() == "b\r"
+assert n.readline() == ""
+
+# 9. readlines keeps reading past a delimiter that lands exactly on the chunk
+# boundary and drains the buffer mid-stream (the first line fills the whole
+# 8192-byte chunk).
+o = open(DATA_CHUNK_END, "r")
+assert o.readlines() == ["x" * 8191 + "\n", "tail\n"]
+p = open(DATA_CHUNK_END, "r")
+assert p.readline() == "x" * 8191 + "\n"
+assert p.readlines() == ["tail\n"]
+
+print("file_readline: ok")

integration/tests/file_readline_data.txt

@@ -0,0 +1,3 @@
+a
+bb
+ccc

integration/tests/file_readline_data_chunk_end.txt

@@ -0,0 +1,2 @@
+xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx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+tail

integration/tests/file_readline_data_cr_tail.txt

@@ -0,0 +1,2 @@
+a
+b

integration/tests/file_readline_data_crlf.txt

@@ -0,0 +1,2 @@
+one
+two

integration/tests/file_buffered_read.py

@@ -0,0 +1,44 @@
+# Regression test: BufferedReader.read1(n)/read(n) must return at most n
+# bytes and never None. Previously the buffered fast path returned every
+# buffered byte regardless of n, or None when fewer than n bytes were
+# buffered.
+
+# Run with cwd == integration/ (as the integration runner does).
+DATA = "tests/file_readline_data.txt" # b"a\nbb\nccc"
+
+# 1. read1 returns at most n bytes; "" at EOF.
+f = open(DATA, "rb")
+assert f.read1(3) == b"a\nb"
+assert f.read1(0) == b""
+assert f.read1(100) == b"b\nccc"
+assert f.read1(4) == b""
+assert f.read1() == b""
+f.close()
+
+# 2. read(n) returns exactly n bytes until the stream runs out.
+g = open(DATA, "rb")
+assert g.read(2) == b"a\n"
+assert g.read(100) == b"bb\nccc"
+assert g.read(1) == b""
+g.close()
+
+# 3. read() with no argument reads everything.
+h = open(DATA, "rb")
+assert h.read() == b"a\nbb\nccc"
+assert h.read() == b""
+h.close()
+
+# 4. readinto fills a writable buffer and returns the byte count; read-only
+# buffers (bytes) must be rejected instead of silently written to.
+i = open(DATA, "rb")
+ba = bytearray(b"xyz")
+assert i.readinto(ba) == 3
+assert ba == bytearray(b"a\nb")
+try:
+ i.readinto(b"xxxx")
+ assert False, "readinto(bytes) must raise TypeError"
+except TypeError:
+ pass
+i.close()
+
+print("file_buffered_read: ok")

integration/tests/file_readline.py

@@ -0,0 +1,85 @@
+# Regression test: TextIOWrapper.readline must return one line at a time
+# (including the line ending), honour the size limit, keep lines that span
+# the 8192-byte read chunks intact, and return "" at EOF. Previously a single
+# call concatenated lines, dropped data, or crashed on uneven line lengths.
+
+# Run with cwd == integration/ (as the integration runner does).
+DATA = "tests/file_readline_data.txt" # b"a\nbb\nccc" (no trailing newline)
+DATA_CRLF = "tests/file_readline_data_crlf.txt" # b"one\r\ntwo\r\n"
+DATA_LONG = "tests/file_readline_data_long.txt" # b"x" * 9000 + b"\ntail\n"
+DATA_STRADDLE = "tests/file_readline_data_straddle.txt" # b"x" * 8191 + b"\r\ntail\r\n"
+DATA_CR_TAIL = "tests/file_readline_data_cr_tail.txt" # b"a\nb\r"
+DATA_CHUNK_END = "tests/file_readline_data_chunk_end.txt" # b"x" * 8191 + b"\ntail\n"
+
+# 1. one line per call, trailing newline included, "" at EOF (and stays "").
+f = open(DATA, "r")
+assert f.readline() == "a\n"
+assert f.readline() == "bb\n"
+assert f.readline() == "ccc"
+assert f.readline() == ""
+assert f.readline() == ""
+
+# 2. size limit: at most `limit` characters, the rest stays buffered.
+g = open(DATA, "r")
+assert g.readline(1) == "a"
+assert g.readline(0) == ""
+assert g.readline(100) == "\n"
+assert g.readline(2) == "bb"
+assert g.readline() == "\n"
+assert g.readline() == "ccc"
+
+# 3. \r\n is consumed as a single line ending (no spurious empty line).
+# TODO: with newline=None CPython translates the terminator to "\n"; the
+# decoder is not implemented yet, so the raw ending is returned for now.
+h = open(DATA_CRLF, "r")
+assert h.readline() == "one\r\n"
+assert h.readline() == "two\r\n"
+assert h.readline() == ""
+
+# 4. a line longer than the 8192-byte read chunk is returned whole.
+i = open(DATA_LONG, "r")
+line = i.readline()
+assert len(line) == 9001, len(line)
+assert i.readline() == "tail\n"
+assert i.readline() == ""
+
+# 5. readlines returns the same split.
+j = open(DATA, "r")
+assert j.readlines() == ["a\n", "bb\n", "ccc"]
+
+# 6. a \r\n split across the 8192-byte chunk boundary stays one line ending
+# (the first chunk ends with the \r, the \n arrives with the next chunk).
+k = open(DATA_STRADDLE, "r")
+line = k.readline()
+assert len(line) == 8193, len(line)
+assert line == "x" * 8191 + "\r\n"
+assert k.readline() == "tail\r\n"
+assert k.readline() == ""
+
+# 7. a \r\n straddling the size limit: the \r fits within the limit, the \n
+# stays buffered and becomes its own line on the next call (CPython clamps
+# the found line to size and pushes the remainder back).
+m = open(DATA_CRLF, "r")
+assert m.readline(4) == "one\r"
+assert m.readline() == "\n"
+assert m.readline() == "two\r\n"
+assert m.readline() == ""
+
+# 8. an unresolved trailing \r must not stop an earlier complete line from
+# being returned (on a blocking stream the read-ahead would stall), and a
+# lone \r at EOF terminates the final line.
+n = open(DATA_CR_TAIL, "r")
+assert n.readline() == "a\n"
+assert n.readline() == "b\r"
+assert n.readline() == ""
+
+# 9. readlines keeps reading past a delimiter that lands exactly on the chunk
+# boundary and drains the buffer mid-stream (the first line fills the whole
+# 8192-byte chunk).
+o = open(DATA_CHUNK_END, "r")
+assert o.readlines() == ["x" * 8191 + "\n", "tail\n"]
+p = open(DATA_CHUNK_END, "r")
+assert p.readline() == "x" * 8191 + "\n"
+assert p.readlines() == ["tail\n"]
+
+print("file_readline: ok")

integration/tests/file_readline_data.txt

@@ -0,0 +1,3 @@
+a
+bb
+ccc

integration/tests/file_readline_data_chunk_end.txt

@@ -0,0 +1,2 @@
+xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx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+tail

integration/tests/file_readline_data_cr_tail.txt

@@ -0,0 +1,2 @@
+a
+b

integration/tests/file_readline_data_crlf.txt

@@ -0,0 +1,2 @@
+one
+two

integration/tests/file_buffered_read.py

@@ -0,0 +1,44 @@
+# Regression test: BufferedReader.read1(n)/read(n) must return at most n
+# bytes and never None. Previously the buffered fast path returned every
+# buffered byte regardless of n, or None when fewer than n bytes were
+# buffered.
+
+# Run with cwd == integration/ (as the integration runner does).
+DATA = "tests/file_readline_data.txt" # b"a\nbb\nccc"
+
+# 1. read1 returns at most n bytes; "" at EOF.
+f = open(DATA, "rb")
+assert f.read1(3) == b"a\nb"
+assert f.read1(0) == b""
+assert f.read1(100) == b"b\nccc"
+assert f.read1(4) == b""
+assert f.read1() == b""
+f.close()
+
+# 2. read(n) returns exactly n bytes until the stream runs out.
+g = open(DATA, "rb")
+assert g.read(2) == b"a\n"
+assert g.read(100) == b"bb\nccc"
+assert g.read(1) == b""
+g.close()
+
+# 3. read() with no argument reads everything.
+h = open(DATA, "rb")
+assert h.read() == b"a\nbb\nccc"
+assert h.read() == b""
+h.close()
+
+# 4. readinto fills a writable buffer and returns the byte count; read-only
+# buffers (bytes) must be rejected instead of silently written to.
+i = open(DATA, "rb")
+ba = bytearray(b"xyz")
+assert i.readinto(ba) == 3
+assert ba == bytearray(b"a\nb")
+try:
+ i.readinto(b"xxxx")
+ assert False, "readinto(bytes) must raise TypeError"
+except TypeError:
+ pass
+i.close()
+
+print("file_buffered_read: ok")

integration/tests/file_readline.py

@@ -0,0 +1,85 @@
+# Regression test: TextIOWrapper.readline must return one line at a time
+# (including the line ending), honour the size limit, keep lines that span
+# the 8192-byte read chunks intact, and return "" at EOF. Previously a single
+# call concatenated lines, dropped data, or crashed on uneven line lengths.
+
+# Run with cwd == integration/ (as the integration runner does).
+DATA = "tests/file_readline_data.txt" # b"a\nbb\nccc" (no trailing newline)
+DATA_CRLF = "tests/file_readline_data_crlf.txt" # b"one\r\ntwo\r\n"
+DATA_LONG = "tests/file_readline_data_long.txt" # b"x" * 9000 + b"\ntail\n"
+DATA_STRADDLE = "tests/file_readline_data_straddle.txt" # b"x" * 8191 + b"\r\ntail\r\n"
+DATA_CR_TAIL = "tests/file_readline_data_cr_tail.txt" # b"a\nb\r"
+DATA_CHUNK_END = "tests/file_readline_data_chunk_end.txt" # b"x" * 8191 + b"\ntail\n"
+
+# 1. one line per call, trailing newline included, "" at EOF (and stays "").
+f = open(DATA, "r")
+assert f.readline() == "a\n"
+assert f.readline() == "bb\n"
+assert f.readline() == "ccc"
+assert f.readline() == ""
+assert f.readline() == ""
+
+# 2. size limit: at most `limit` characters, the rest stays buffered.
+g = open(DATA, "r")
+assert g.readline(1) == "a"
+assert g.readline(0) == ""
+assert g.readline(100) == "\n"
+assert g.readline(2) == "bb"
+assert g.readline() == "\n"
+assert g.readline() == "ccc"
+
+# 3. \r\n is consumed as a single line ending (no spurious empty line).
+# TODO: with newline=None CPython translates the terminator to "\n"; the
+# decoder is not implemented yet, so the raw ending is returned for now.
+h = open(DATA_CRLF, "r")
+assert h.readline() == "one\r\n"
+assert h.readline() == "two\r\n"
+assert h.readline() == ""
+
+# 4. a line longer than the 8192-byte read chunk is returned whole.
+i = open(DATA_LONG, "r")
+line = i.readline()
+assert len(line) == 9001, len(line)
+assert i.readline() == "tail\n"
+assert i.readline() == ""
+
+# 5. readlines returns the same split.
+j = open(DATA, "r")
+assert j.readlines() == ["a\n", "bb\n", "ccc"]
+
+# 6. a \r\n split across the 8192-byte chunk boundary stays one line ending
+# (the first chunk ends with the \r, the \n arrives with the next chunk).
+k = open(DATA_STRADDLE, "r")
+line = k.readline()
+assert len(line) == 8193, len(line)
+assert line == "x" * 8191 + "\r\n"
+assert k.readline() == "tail\r\n"
+assert k.readline() == ""
+
+# 7. a \r\n straddling the size limit: the \r fits within the limit, the \n
+# stays buffered and becomes its own line on the next call (CPython clamps
+# the found line to size and pushes the remainder back).
+m = open(DATA_CRLF, "r")
+assert m.readline(4) == "one\r"
+assert m.readline() == "\n"
+assert m.readline() == "two\r\n"
+assert m.readline() == ""
+
+# 8. an unresolved trailing \r must not stop an earlier complete line from
+# being returned (on a blocking stream the read-ahead would stall), and a
+# lone \r at EOF terminates the final line.
+n = open(DATA_CR_TAIL, "r")
+assert n.readline() == "a\n"
+assert n.readline() == "b\r"
+assert n.readline() == ""
+
+# 9. readlines keeps reading past a delimiter that lands exactly on the chunk
+# boundary and drains the buffer mid-stream (the first line fills the whole
+# 8192-byte chunk).
+o = open(DATA_CHUNK_END, "r")
+assert o.readlines() == ["x" * 8191 + "\n", "tail\n"]
+p = open(DATA_CHUNK_END, "r")
+assert p.readline() == "x" * 8191 + "\n"
+assert p.readlines() == ["tail\n"]
+
+print("file_readline: ok")

integration/tests/file_readline_data.txt

@@ -0,0 +1,3 @@
+a
+bb
+ccc

integration/tests/file_readline_data_chunk_end.txt

@@ -0,0 +1,2 @@
+xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx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+tail

integration/tests/file_readline_data_cr_tail.txt

@@ -0,0 +1,2 @@
+a
+b

integration/tests/file_readline_data_crlf.txt

@@ -0,0 +1,2 @@
+one
+two

integration/tests/file_buffered_read.py

@@ -0,0 +1,44 @@
+# Regression test: BufferedReader.read1(n)/read(n) must return at most n
+# bytes and never None. Previously the buffered fast path returned every
+# buffered byte regardless of n, or None when fewer than n bytes were
+# buffered.
+
+# Run with cwd == integration/ (as the integration runner does).
+DATA = "tests/file_readline_data.txt" # b"a\nbb\nccc"
+
+# 1. read1 returns at most n bytes; "" at EOF.
+f = open(DATA, "rb")
+assert f.read1(3) == b"a\nb"
+assert f.read1(0) == b""
+assert f.read1(100) == b"b\nccc"
+assert f.read1(4) == b""
+assert f.read1() == b""
+f.close()
+
+# 2. read(n) returns exactly n bytes until the stream runs out.
+g = open(DATA, "rb")
+assert g.read(2) == b"a\n"
+assert g.read(100) == b"bb\nccc"
+assert g.read(1) == b""
+g.close()
+
+# 3. read() with no argument reads everything.
+h = open(DATA, "rb")
+assert h.read() == b"a\nbb\nccc"
+assert h.read() == b""
+h.close()
+
+# 4. readinto fills a writable buffer and returns the byte count; read-only
+# buffers (bytes) must be rejected instead of silently written to.
+i = open(DATA, "rb")
+ba = bytearray(b"xyz")
+assert i.readinto(ba) == 3
+assert ba == bytearray(b"a\nb")
+try:
+ i.readinto(b"xxxx")
+ assert False, "readinto(bytes) must raise TypeError"
+except TypeError:
+ pass
+i.close()
+
+print("file_buffered_read: ok")

integration/tests/file_readline.py

@@ -0,0 +1,85 @@
+# Regression test: TextIOWrapper.readline must return one line at a time
+# (including the line ending), honour the size limit, keep lines that span
+# the 8192-byte read chunks intact, and return "" at EOF. Previously a single
+# call concatenated lines, dropped data, or crashed on uneven line lengths.
+
+# Run with cwd == integration/ (as the integration runner does).
+DATA = "tests/file_readline_data.txt" # b"a\nbb\nccc" (no trailing newline)
+DATA_CRLF = "tests/file_readline_data_crlf.txt" # b"one\r\ntwo\r\n"
+DATA_LONG = "tests/file_readline_data_long.txt" # b"x" * 9000 + b"\ntail\n"
+DATA_STRADDLE = "tests/file_readline_data_straddle.txt" # b"x" * 8191 + b"\r\ntail\r\n"
+DATA_CR_TAIL = "tests/file_readline_data_cr_tail.txt" # b"a\nb\r"
+DATA_CHUNK_END = "tests/file_readline_data_chunk_end.txt" # b"x" * 8191 + b"\ntail\n"
+
+# 1. one line per call, trailing newline included, "" at EOF (and stays "").
+f = open(DATA, "r")
+assert f.readline() == "a\n"
+assert f.readline() == "bb\n"
+assert f.readline() == "ccc"
+assert f.readline() == ""
+assert f.readline() == ""
+
+# 2. size limit: at most `limit` characters, the rest stays buffered.
+g = open(DATA, "r")
+assert g.readline(1) == "a"
+assert g.readline(0) == ""
+assert g.readline(100) == "\n"
+assert g.readline(2) == "bb"
+assert g.readline() == "\n"
+assert g.readline() == "ccc"
+
+# 3. \r\n is consumed as a single line ending (no spurious empty line).
+# TODO: with newline=None CPython translates the terminator to "\n"; the
+# decoder is not implemented yet, so the raw ending is returned for now.
+h = open(DATA_CRLF, "r")
+assert h.readline() == "one\r\n"
+assert h.readline() == "two\r\n"
+assert h.readline() == ""
+
+# 4. a line longer than the 8192-byte read chunk is returned whole.
+i = open(DATA_LONG, "r")
+line = i.readline()
+assert len(line) == 9001, len(line)
+assert i.readline() == "tail\n"
+assert i.readline() == ""
+
+# 5. readlines returns the same split.
+j = open(DATA, "r")
+assert j.readlines() == ["a\n", "bb\n", "ccc"]
+
+# 6. a \r\n split across the 8192-byte chunk boundary stays one line ending
+# (the first chunk ends with the \r, the \n arrives with the next chunk).
+k = open(DATA_STRADDLE, "r")
+line = k.readline()
+assert len(line) == 8193, len(line)
+assert line == "x" * 8191 + "\r\n"
+assert k.readline() == "tail\r\n"
+assert k.readline() == ""
+
+# 7. a \r\n straddling the size limit: the \r fits within the limit, the \n
+# stays buffered and becomes its own line on the next call (CPython clamps
+# the found line to size and pushes the remainder back).
+m = open(DATA_CRLF, "r")
+assert m.readline(4) == "one\r"
+assert m.readline() == "\n"
+assert m.readline() == "two\r\n"
+assert m.readline() == ""
+
+# 8. an unresolved trailing \r must not stop an earlier complete line from
+# being returned (on a blocking stream the read-ahead would stall), and a
+# lone \r at EOF terminates the final line.
+n = open(DATA_CR_TAIL, "r")
+assert n.readline() == "a\n"
+assert n.readline() == "b\r"
+assert n.readline() == ""
+
+# 9. readlines keeps reading past a delimiter that lands exactly on the chunk
+# boundary and drains the buffer mid-stream (the first line fills the whole
+# 8192-byte chunk).
+o = open(DATA_CHUNK_END, "r")
+assert o.readlines() == ["x" * 8191 + "\n", "tail\n"]
+p = open(DATA_CHUNK_END, "r")
+assert p.readline() == "x" * 8191 + "\n"
+assert p.readlines() == ["tail\n"]
+
+print("file_readline: ok")

integration/tests/file_readline_data.txt

@@ -0,0 +1,3 @@
+a
+bb
+ccc

integration/tests/file_readline_data_chunk_end.txt

@@ -0,0 +1,2 @@
+xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx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+tail

integration/tests/file_readline_data_cr_tail.txt

@@ -0,0 +1,2 @@
+a
+b

integration/tests/file_readline_data_crlf.txt

@@ -0,0 +1,2 @@
+one
+two

integration/tests/file_buffered_read.py

@@ -0,0 +1,44 @@
+# Regression test: BufferedReader.read1(n)/read(n) must return at most n
+# bytes and never None. Previously the buffered fast path returned every
+# buffered byte regardless of n, or None when fewer than n bytes were
+# buffered.
+
+# Run with cwd == integration/ (as the integration runner does).
+DATA = "tests/file_readline_data.txt" # b"a\nbb\nccc"
+
+# 1. read1 returns at most n bytes; "" at EOF.
+f = open(DATA, "rb")
+assert f.read1(3) == b"a\nb"
+assert f.read1(0) == b""
+assert f.read1(100) == b"b\nccc"
+assert f.read1(4) == b""
+assert f.read1() == b""
+f.close()
+
+# 2. read(n) returns exactly n bytes until the stream runs out.
+g = open(DATA, "rb")
+assert g.read(2) == b"a\n"
+assert g.read(100) == b"bb\nccc"
+assert g.read(1) == b""
+g.close()
+
+# 3. read() with no argument reads everything.
+h = open(DATA, "rb")
+assert h.read() == b"a\nbb\nccc"
+assert h.read() == b""
+h.close()
+
+# 4. readinto fills a writable buffer and returns the byte count; read-only
+# buffers (bytes) must be rejected instead of silently written to.
+i = open(DATA, "rb")
+ba = bytearray(b"xyz")
+assert i.readinto(ba) == 3
+assert ba == bytearray(b"a\nb")
+try:
+ i.readinto(b"xxxx")
+ assert False, "readinto(bytes) must raise TypeError"
+except TypeError:
+ pass
+i.close()
+
+print("file_buffered_read: ok")

integration/tests/file_readline.py

@@ -0,0 +1,85 @@
+# Regression test: TextIOWrapper.readline must return one line at a time
+# (including the line ending), honour the size limit, keep lines that span
+# the 8192-byte read chunks intact, and return "" at EOF. Previously a single
+# call concatenated lines, dropped data, or crashed on uneven line lengths.
+
+# Run with cwd == integration/ (as the integration runner does).
+DATA = "tests/file_readline_data.txt" # b"a\nbb\nccc" (no trailing newline)
+DATA_CRLF = "tests/file_readline_data_crlf.txt" # b"one\r\ntwo\r\n"
+DATA_LONG = "tests/file_readline_data_long.txt" # b"x" * 9000 + b"\ntail\n"
+DATA_STRADDLE = "tests/file_readline_data_straddle.txt" # b"x" * 8191 + b"\r\ntail\r\n"
+DATA_CR_TAIL = "tests/file_readline_data_cr_tail.txt" # b"a\nb\r"
+DATA_CHUNK_END = "tests/file_readline_data_chunk_end.txt" # b"x" * 8191 + b"\ntail\n"
+
+# 1. one line per call, trailing newline included, "" at EOF (and stays "").
+f = open(DATA, "r")
+assert f.readline() == "a\n"
+assert f.readline() == "bb\n"
+assert f.readline() == "ccc"
+assert f.readline() == ""
+assert f.readline() == ""
+
+# 2. size limit: at most `limit` characters, the rest stays buffered.
+g = open(DATA, "r")
+assert g.readline(1) == "a"
+assert g.readline(0) == ""
+assert g.readline(100) == "\n"
+assert g.readline(2) == "bb"
+assert g.readline() == "\n"
+assert g.readline() == "ccc"
+
+# 3. \r\n is consumed as a single line ending (no spurious empty line).
+# TODO: with newline=None CPython translates the terminator to "\n"; the
+# decoder is not implemented yet, so the raw ending is returned for now.
+h = open(DATA_CRLF, "r")
+assert h.readline() == "one\r\n"
+assert h.readline() == "two\r\n"
+assert h.readline() == ""
+
+# 4. a line longer than the 8192-byte read chunk is returned whole.
+i = open(DATA_LONG, "r")
+line = i.readline()
+assert len(line) == 9001, len(line)
+assert i.readline() == "tail\n"
+assert i.readline() == ""
+
+# 5. readlines returns the same split.
+j = open(DATA, "r")
+assert j.readlines() == ["a\n", "bb\n", "ccc"]
+
+# 6. a \r\n split across the 8192-byte chunk boundary stays one line ending
+# (the first chunk ends with the \r, the \n arrives with the next chunk).
+k = open(DATA_STRADDLE, "r")
+line = k.readline()
+assert len(line) == 8193, len(line)
+assert line == "x" * 8191 + "\r\n"
+assert k.readline() == "tail\r\n"
+assert k.readline() == ""
+
+# 7. a \r\n straddling the size limit: the \r fits within the limit, the \n
+# stays buffered and becomes its own line on the next call (CPython clamps
+# the found line to size and pushes the remainder back).
+m = open(DATA_CRLF, "r")
+assert m.readline(4) == "one\r"
+assert m.readline() == "\n"
+assert m.readline() == "two\r\n"
+assert m.readline() == ""
+
+# 8. an unresolved trailing \r must not stop an earlier complete line from
+# being returned (on a blocking stream the read-ahead would stall), and a
+# lone \r at EOF terminates the final line.
+n = open(DATA_CR_TAIL, "r")
+assert n.readline() == "a\n"
+assert n.readline() == "b\r"
+assert n.readline() == ""
+
+# 9. readlines keeps reading past a delimiter that lands exactly on the chunk
+# boundary and drains the buffer mid-stream (the first line fills the whole
+# 8192-byte chunk).
+o = open(DATA_CHUNK_END, "r")
+assert o.readlines() == ["x" * 8191 + "\n", "tail\n"]
+p = open(DATA_CHUNK_END, "r")
+assert p.readline() == "x" * 8191 + "\n"
+assert p.readlines() == ["tail\n"]
+
+print("file_readline: ok")

integration/tests/file_readline_data.txt

@@ -0,0 +1,3 @@
+a
+bb
+ccc

integration/tests/file_readline_data_chunk_end.txt

@@ -0,0 +1,2 @@
+xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx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+tail

integration/tests/file_readline_data_cr_tail.txt

@@ -0,0 +1,2 @@
+a
+b

integration/tests/file_readline_data_crlf.txt

@@ -0,0 +1,2 @@
+one
+two

integration/tests/file_buffered_read.py

@@ -0,0 +1,44 @@
+# Regression test: BufferedReader.read1(n)/read(n) must return at most n
+# bytes and never None. Previously the buffered fast path returned every
+# buffered byte regardless of n, or None when fewer than n bytes were
+# buffered.
+
+# Run with cwd == integration/ (as the integration runner does).
+DATA = "tests/file_readline_data.txt" # b"a\nbb\nccc"
+
+# 1. read1 returns at most n bytes; "" at EOF.
+f = open(DATA, "rb")
+assert f.read1(3) == b"a\nb"
+assert f.read1(0) == b""
+assert f.read1(100) == b"b\nccc"
+assert f.read1(4) == b""
+assert f.read1() == b""
+f.close()
+
+# 2. read(n) returns exactly n bytes until the stream runs out.
+g = open(DATA, "rb")
+assert g.read(2) == b"a\n"
+assert g.read(100) == b"bb\nccc"
+assert g.read(1) == b""
+g.close()
+
+# 3. read() with no argument reads everything.
+h = open(DATA, "rb")
+assert h.read() == b"a\nbb\nccc"
+assert h.read() == b""
+h.close()
+
+# 4. readinto fills a writable buffer and returns the byte count; read-only
+# buffers (bytes) must be rejected instead of silently written to.
+i = open(DATA, "rb")
+ba = bytearray(b"xyz")
+assert i.readinto(ba) == 3
+assert ba == bytearray(b"a\nb")
+try:
+ i.readinto(b"xxxx")
+ assert False, "readinto(bytes) must raise TypeError"
+except TypeError:
+ pass
+i.close()
+
+print("file_buffered_read: ok")

integration/tests/file_readline.py

@@ -0,0 +1,85 @@
+# Regression test: TextIOWrapper.readline must return one line at a time
+# (including the line ending), honour the size limit, keep lines that span
+# the 8192-byte read chunks intact, and return "" at EOF. Previously a single
+# call concatenated lines, dropped data, or crashed on uneven line lengths.
+
+# Run with cwd == integration/ (as the integration runner does).
+DATA = "tests/file_readline_data.txt" # b"a\nbb\nccc" (no trailing newline)
+DATA_CRLF = "tests/file_readline_data_crlf.txt" # b"one\r\ntwo\r\n"
+DATA_LONG = "tests/file_readline_data_long.txt" # b"x" * 9000 + b"\ntail\n"
+DATA_STRADDLE = "tests/file_readline_data_straddle.txt" # b"x" * 8191 + b"\r\ntail\r\n"
+DATA_CR_TAIL = "tests/file_readline_data_cr_tail.txt" # b"a\nb\r"
+DATA_CHUNK_END = "tests/file_readline_data_chunk_end.txt" # b"x" * 8191 + b"\ntail\n"
+
+# 1. one line per call, trailing newline included, "" at EOF (and stays "").
+f = open(DATA, "r")
+assert f.readline() == "a\n"
+assert f.readline() == "bb\n"
+assert f.readline() == "ccc"
+assert f.readline() == ""
+assert f.readline() == ""
+
+# 2. size limit: at most `limit` characters, the rest stays buffered.
+g = open(DATA, "r")
+assert g.readline(1) == "a"
+assert g.readline(0) == ""
+assert g.readline(100) == "\n"
+assert g.readline(2) == "bb"
+assert g.readline() == "\n"
+assert g.readline() == "ccc"
+
+# 3. \r\n is consumed as a single line ending (no spurious empty line).
+# TODO: with newline=None CPython translates the terminator to "\n"; the
+# decoder is not implemented yet, so the raw ending is returned for now.
+h = open(DATA_CRLF, "r")
+assert h.readline() == "one\r\n"
+assert h.readline() == "two\r\n"
+assert h.readline() == ""
+
+# 4. a line longer than the 8192-byte read chunk is returned whole.
+i = open(DATA_LONG, "r")
+line = i.readline()
+assert len(line) == 9001, len(line)
+assert i.readline() == "tail\n"
+assert i.readline() == ""
+
+# 5. readlines returns the same split.
+j = open(DATA, "r")
+assert j.readlines() == ["a\n", "bb\n", "ccc"]
+
+# 6. a \r\n split across the 8192-byte chunk boundary stays one line ending
+# (the first chunk ends with the \r, the \n arrives with the next chunk).
+k = open(DATA_STRADDLE, "r")
+line = k.readline()
+assert len(line) == 8193, len(line)
+assert line == "x" * 8191 + "\r\n"
+assert k.readline() == "tail\r\n"
+assert k.readline() == ""
+
+# 7. a \r\n straddling the size limit: the \r fits within the limit, the \n
+# stays buffered and becomes its own line on the next call (CPython clamps
+# the found line to size and pushes the remainder back).
+m = open(DATA_CRLF, "r")
+assert m.readline(4) == "one\r"
+assert m.readline() == "\n"
+assert m.readline() == "two\r\n"
+assert m.readline() == ""
+
+# 8. an unresolved trailing \r must not stop an earlier complete line from
+# being returned (on a blocking stream the read-ahead would stall), and a
+# lone \r at EOF terminates the final line.
+n = open(DATA_CR_TAIL, "r")
+assert n.readline() == "a\n"
+assert n.readline() == "b\r"
+assert n.readline() == ""
+
+# 9. readlines keeps reading past a delimiter that lands exactly on the chunk
+# boundary and drains the buffer mid-stream (the first line fills the whole
+# 8192-byte chunk).
+o = open(DATA_CHUNK_END, "r")
+assert o.readlines() == ["x" * 8191 + "\n", "tail\n"]
+p = open(DATA_CHUNK_END, "r")
+assert p.readline() == "x" * 8191 + "\n"
+assert p.readlines() == ["tail\n"]
+
+print("file_readline: ok")

integration/tests/file_readline_data.txt

@@ -0,0 +1,3 @@
+a
+bb
+ccc

integration/tests/file_readline_data_chunk_end.txt

@@ -0,0 +1,2 @@
+xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
+tail

integration/tests/file_readline_data_cr_tail.txt

@@ -0,0 +1,2 @@
+a
+b

integration/tests/file_readline_data_crlf.txt

@@ -0,0 +1,2 @@
+one
+two