Feb 3, 2026 · Feb 3, 2026
diff --git a/Android/android.py b/Android/android.py
 fromasyncioimportwait_for
 fromcontextlibimportasynccontextmanager
 fromdatetimeimportdatetime,timezone
 fromenumimportIntEnum,auto
 fromglobimportglob
 fromos.pathimportabspath,basename,relpath
 frompathlibimportPath
 hidden_output= []


 # Based on android/log.h in the NDK.
 classLogPriority(IntEnum):
 UNKNOWN=0
 DEFAULT=auto()
 VERBOSE=auto()
 DEBUG=auto()
 INFO=auto()
 WARN=auto()
 ERROR=auto()
 FATAL=auto()
 SILENT=auto()


 deflog_verbose(context,line,stream=sys.stdout):
 ifcontext.verbose:
 stream.write(line)
 pid=awaitwait_for(find_pid(serial),startup_timeout)

 # `--pid` requires API level 24 or higher.
 args= [adb,"-s",serial,"logcat","--pid",pid,"--format","tag"]
 #
 # `--binary` mode is used in order to detect which messages end with a
 # newline, which most of the other modes don't indicate (except `--format
 # long`). For example, every time pytest runs a test, it prints a "." and
 # flushes the stream. Each "." becomes a separate log message, but we should
 # show them all on the same line.
 args= [adb,"-s",serial,"logcat","--pid",pid,"--binary"]
 logcat_started=False
 asyncwithasync_process(
 *args,stdout=subprocess.PIPE,stderr=subprocess.STDOUT,
 *args,stdout=subprocess.PIPE,stderr=None
    )asprocess:
 whileline:= (awaitprocess.stdout.readline()).decode(*DECODE_ARGS):
 ifmatch:=re.fullmatch(r"([A-Z])/(.*)",line,re.DOTALL):
 whileTrue:
 try:
 priority,tag,message=awaitread_logcat(process.stdout)
 logcat_started=True
 level,message=match.groups()
 else:
 # If the regex doesn't match, this is either a logcat startup
 # error, or the second or subsequent line of a multi-line
 # message. Python won't produce multi-line messages, but other
 # components might.
 level,message=None,line
 exceptasyncio.IncompleteReadError:
 break

 # Exclude high-volume messages which are rarely useful.
 ifcontext.verbose<2and"from python test_syslog"inmessage:
 continue

 # Put high-level messages on stderr so they're highlighted in the
 # buildbot logs. This will include Python's own stderr.
 stream= (
 sys.stderr
 iflevelin ["W","E","F"]# WARNING, ERROR, FATAL (aka ASSERT)
 elsesys.stdout
            )

 # To simplify automated processing of the output, e.g. a buildbot
 # posting a failure notice on a GitHub PR, we strip the level and
 # tag indicators from Python's stdout and stderr.
 forprefixin ["python.stdout: ","python.stderr: "]:
 ifmessage.startswith(prefix):
 globalpython_started
 python_started=True
 stream.write(message.removeprefix(prefix))
 break
 stream=sys.stderrifpriority>=LogPriority.WARNelsesys.stdout

 # The app's stdout and stderr should be passed through transparently
 # to our own corresponding streams.
 iftagin ["python.stdout","python.stderr"]:
 globalpython_started
 python_started=True
 stream.write(message)
 stream.flush()
 else:
 # Non-Python messages add a lot of noise, but they may
 # sometimes help explain a failure.
 log_verbose(context,line,stream)
 # sometimes help explain a failure. Format them in the same way
 # as `logcat --format tag`.
 formatted=f"{priority.name[0]}/{tag}:{message}"
 ifnotformatted.endswith("\n"):
 formatted+="\n"
 log_verbose(context,formatted,stream)

 # If the device disconnects while logcat is running, which always
 # happens in --managed mode, some versions of adb return non-zero.
 raiseCalledProcessError(status,args)


 # Read one binary log message from the given StreamReader. The message format is
 # described at https://android.stackexchange.com/a/74660. All supported versions
 # of Android use format version 2 or later.
 asyncdefread_logcat(stream):
 asyncdefread_bytes(size):
 returnawaitstream.readexactly(size)

 asyncdefread_int(size):
 returnint.from_bytes(awaitread_bytes(size),"little")

 payload_len=awaitread_int(2)
 ifpayload_len<2:
 # 1 byte for priority, 1 byte for null terminator of tag.
 raiseValueError(f"payload length{payload_len} is too short")

 header_len=awaitread_int(2)
 ifheader_len<4:
 raiseValueError(f"header length{header_len} is too short")
 awaitread_bytes(header_len-4)# Ignore other header fields.

 priority_int=awaitread_int(1)
 try:
 priority=LogPriority(priority_int)
 exceptValueError:
 priority=LogPriority.UNKNOWN

 payload_fields= (awaitread_bytes(payload_len-1)).split(b"\0")
 iflen(payload_fields)<2:
 raiseValueError(
 f"payload{payload!r} does not contain at least 2 "
 f"null-separated fields"
        )
 tag,message,*_= [
 field.decode(*DECODE_ARGS)forfieldinpayload_fields
    ]
 returnpriority,tag,message


 defstop_app(serial):
 run([adb,"-s",serial,"shell","am","force-stop",APP_ID],log=False)

diff --git a/Android/testbed/app/build.gradle.kts b/Android/testbed/app/build.gradle.kts
        }

        // This controls the API level of the maxVersion managed emulator, which is used
        // by CI and cibuildwheel. 34 takes up too much disk space (#142289), 35 has
        // issues connecting to the internet (#142387), and 36 and later are not
        // available as aosp_atd images yet.
        targetSdk = 33
        // by CI and cibuildwheel.
        //  * 33 has excessive buffering in the logcat client
        //    (https://cs.android.com/android/_/android/platform/system/logging/+/d340721894f223327339010df59b0ac514308826).
        //  * 34 consumes too much disk space on GitHub Actions (#142289).
        //  * 35 has issues connecting to the internet (#142387).
        //  * 36 and later are not available as aosp_atd images yet.
        targetSdk = 32

        versionCode = 1
        versionName = "1.0"
        path("src/main/c/CMakeLists.txt")
    }

    // Set this property to something non-empty, otherwise it'll use the default
    // list, which ignores asset directories beginning with an underscore.
    aaptOptions.ignoreAssetsPattern = ".git"
    // Set this property to something nonexistent but non-empty. Otherwise it'll use the
    // default list, which ignores asset directories beginning with an underscore, and
    // maybe also other files required by tests.
    aaptOptions.ignoreAssetsPattern = "android-testbed-dont-ignore-anything"

    compileOptions {
        sourceCompatibility = JavaVersion.VERSION_1_8
                    from(cwd)
                }
            }

            // A filename ending with .gz will be automatically decompressed
            // while building the APK. Avoid this by adding a dash to the end,
            // and add an extra dash to any filenames that already end with one.
            // This will be undone in MainActivity.kt.
            rename(""".*(\.gz|-)""", "$0-")
        }
    }

diff --git a/Android/testbed/app/src/main/java/org/python/testbed/MainActivity.kt b/Android/testbed/app/src/main/java/org/python/testbed/MainActivity.kt
 continue
            }
            input.use {
 File(targetSubdir, name).outputStream().use { output->
 // Undo the .gz workaround from build.gradle.kts.
 val outputName= name.replace(Regex("""(.*)-"""),"$1")
 File(targetSubdir, outputName).outputStream().use { output->
                    input.copyTo(output)
                }
            }
diff --git a/Lib/_android_support.py b/Lib/_android_support.py
 # message.
 message=message.replace(b"\x00",b"\xc0\x80")

 # On API level 30 and higher, Logcat will strip any number of leading
 # newlines. This is visible in all `logcat` modes, even --binary. Work
 # around this by adding a leading space, which shouldn't make any
 # difference to the log's usability.
 ifmessage.startswith(b"\n"):
 message=b" "+message

 withself._lock:
 now=time()
 self._bucket_level+= (
diff --git a/Lib/test/test_android.py b/Lib/test/test_android.py
 importio
 importplatform
 importqueue
 importre
 importsubprocess
 ifsys.platform!="android":
 raiseunittest.SkipTest("Android-specific")

 api_level=platform.android_ver().api_level

 # (name, level, fileno)
 STREAM_INFO= [("stdout","I",1), ("stderr","W",2)]


 # Multi-line messages. Avoid identical consecutive lines, as
 # they may activate "chatty" filtering and break the tests.
 write("\nx", [""])
 #
 # Additional spaces will appear in the output where necessary to
 # protect leading newlines.
 write("\nx", [" "])
 write("\na\n", ["x","a"])
 write("\n", [""])
 write("\n", [" "])
 write("\n\n", [" "," "])
 write("b\n", ["b"])
 write("c\n\n", ["c",""])
 write("c\n\n", ["c",""])
 write("d\ne", ["d"])
 write("xx", [])
 write("f\n\ng", ["exxf",""])
 write("f\n\ng", ["exxf",""])
 write("\n", ["g"])

 # Since this is a line-based logging system, line buffering
 # However, buffering can be turned off completely if you want a
 # flush after every write.
 withself.reconfigure(stream,write_through=True):
 write("\nx", ["","x"])
 write("\na\n", ["","a"])
 write("\n", [""])
 write("\nx", [" ","x"])
 write("\na\n", [" ","a"])
 write("\n", [" "])
 write("\n\n", [" "," "])
 write("b\n", ["b"])
 write("c\n\n", ["c",""])
 write("c\n\n", ["c",""])
 write("d\ne", ["d","e"])
 write("xx", ["xx"])
 write("f\n\ng", ["f","","g"])
 write("\n", [""])
 write("f\n\ng", ["f","","g"])
 write("\n", [""])

 # "\r\n" should be translated into "\n".
 write("hello\r\n", ["hello"])
 # currently use `logcat -v tag`, which shows each line as if it
 # was a separate log entry, but strips a single trailing
 # newline.
 #
 # On newer versions of Android, all three of the above tools (or
 # maybe Logcat itself) will also strip any number of leading
 # newlines.
 write(b"\nx", ["","x"]ifapi_level<30else ["x"])
 write(b"\na\n", ["","a"]ifapi_level<30else ["a"])
 write(b"\n", [""])
 write(b"\nx", [" ","x"])
 write(b"\na\n", [" ","a"])
 write(b"\n", [" "])
 write(b"\n\n", [" ",""])
 write(b"b\n", ["b"])
 write(b"c\n\n", ["c",""])
 write(b"d\ne", ["d","e"])
 write(b"xx", ["xx"])
 write(b"f\n\ng", ["f","","g"])
 write(b"\n", [""])
 write(b"\n", [""])

 # "\r\n" should be translated into "\n".
 write(b"hello\r\n", ["hello"])
diff --git a/Misc/NEWS.d/next/Tests/2026-02-03-07-57-24.gh-issue-144415.U3L15r.rst b/Misc/NEWS.d/next/Tests/2026-02-03-07-57-24.gh-issue-144415.U3L15r.rst
 The Android testbed now distinguishes between stdout/stderr messages which
 were triggered by a newline, and those triggered by a manual call to
 ``flush``. This fixes logging of progress indicators and similar content.
Original file line number	Diff line number	Diff line change
Expand Up		@@ -15,6 +15,7 @@
		fromasyncioimportwait_for
		fromcontextlibimportasynccontextmanager
		fromdatetimeimportdatetime,timezone
		fromenumimportIntEnum,auto
		fromglobimportglob
		fromos.pathimportabspath,basename,relpath
		frompathlibimportPath
Expand DownExpand Up		@@ -61,6 +62,19 @@
		hidden_output= []


		# Based on android/log.h in the NDK.
		classLogPriority(IntEnum):
		UNKNOWN=0
		DEFAULT=auto()
		VERBOSE=auto()
		DEBUG=auto()
		INFO=auto()
		WARN=auto()
		ERROR=auto()
		FATAL=auto()
		SILENT=auto()


		deflog_verbose(context,line,stream=sys.stdout):
		ifcontext.verbose:
		stream.write(line)
Expand DownExpand Up		@@ -505,47 +519,47 @@ async def logcat_task(context, initial_devices):
		pid=awaitwait_for(find_pid(serial),startup_timeout)

		# `--pid` requires API level 24 or higher.
		args= [adb,"-s",serial,"logcat","--pid",pid,"--format","tag"]
		#
		# `--binary` mode is used in order to detect which messages end with a
		# newline, which most of the other modes don't indicate (except `--format
		# long`). For example, every time pytest runs a test, it prints a "." and
		# flushes the stream. Each "." becomes a separate log message, but we should
		# show them all on the same line.
		args= [adb,"-s",serial,"logcat","--pid",pid,"--binary"]
		logcat_started=False
		asyncwithasync_process(
		*args,stdout=subprocess.PIPE,stderr=subprocess.STDOUT,
		*args,stdout=subprocess.PIPE,stderr=None
		)asprocess:
		whileline:= (awaitprocess.stdout.readline()).decode(*DECODE_ARGS):
		ifmatch:=re.fullmatch(r"([A-Z])/(.*)",line,re.DOTALL):
		whileTrue:
		try:
		priority,tag,message=awaitread_logcat(process.stdout)
		logcat_started=True
		level,message=match.groups()
		else:
		# If the regex doesn't match, this is either a logcat startup
		# error, or the second or subsequent line of a multi-line
		# message. Python won't produce multi-line messages, but other
		# components might.
		level,message=None,line
		exceptasyncio.IncompleteReadError:
		break

		# Exclude high-volume messages which are rarely useful.
		ifcontext.verbose<2and"from python test_syslog"inmessage:
		continue

		# Put high-level messages on stderr so they're highlighted in the
		# buildbot logs. This will include Python's own stderr.
		stream= (
		sys.stderr
		iflevelin ["W","E","F"]# WARNING, ERROR, FATAL (aka ASSERT)
		elsesys.stdout
		)

		# To simplify automated processing of the output, e.g. a buildbot
		# posting a failure notice on a GitHub PR, we strip the level and
		# tag indicators from Python's stdout and stderr.
		forprefixin ["python.stdout: ","python.stderr: "]:
		ifmessage.startswith(prefix):
		globalpython_started
		python_started=True
		stream.write(message.removeprefix(prefix))
		break
		stream=sys.stderrifpriority>=LogPriority.WARNelsesys.stdout

		# The app's stdout and stderr should be passed through transparently
		# to our own corresponding streams.
		iftagin ["python.stdout","python.stderr"]:
		globalpython_started
		python_started=True
		stream.write(message)
		stream.flush()
		else:
		# Non-Python messages add a lot of noise, but they may
		# sometimes help explain a failure.
		log_verbose(context,line,stream)
		# sometimes help explain a failure. Format them in the same way
		# as `logcat --format tag`.
		formatted=f"{priority.name[0]}/{tag}:{message}"
		ifnotformatted.endswith("\n"):
		formatted+="\n"
		log_verbose(context,formatted,stream)

		# If the device disconnects while logcat is running, which always
		# happens in --managed mode, some versions of adb return non-zero.
Expand All		@@ -556,6 +570,44 @@ async def logcat_task(context, initial_devices):
		raiseCalledProcessError(status,args)


		# Read one binary log message from the given StreamReader. The message format is
		# described at https://android.stackexchange.com/a/74660. All supported versions
		# of Android use format version 2 or later.
		asyncdefread_logcat(stream):
		asyncdefread_bytes(size):
		returnawaitstream.readexactly(size)

		asyncdefread_int(size):
		returnint.from_bytes(awaitread_bytes(size),"little")

		payload_len=awaitread_int(2)
		ifpayload_len<2:
		# 1 byte for priority, 1 byte for null terminator of tag.
		raiseValueError(f"payload length{payload_len} is too short")

		header_len=awaitread_int(2)
		ifheader_len<4:
		raiseValueError(f"header length{header_len} is too short")
		awaitread_bytes(header_len-4)# Ignore other header fields.

		priority_int=awaitread_int(1)
		try:
		priority=LogPriority(priority_int)
		exceptValueError:
		priority=LogPriority.UNKNOWN

		payload_fields= (awaitread_bytes(payload_len-1)).split(b"\0")
		iflen(payload_fields)<2:
		raiseValueError(
		f"payload{payload!r} does not contain at least 2 "
		f"null-separated fields"
		)
		tag,message,*_= [
		field.decode(*DECODE_ARGS)forfieldinpayload_fields
		]
		returnpriority,tag,message


		defstop_app(serial):
		run([adb,"-s",serial,"shell","am","force-stop",APP_ID],log=False)

Expand Down
Original file line number	Diff line number	Diff line change
Expand Up		@@ -94,10 +94,13 @@ android {
		}

		// This controls the API level of the maxVersion managed emulator, which is used
		// by CI and cibuildwheel. 34 takes up too much disk space (#142289), 35 has
		// issues connecting to the internet (#142387), and 36 and later are not
		// available as aosp_atd images yet.
		targetSdk = 33
		// by CI and cibuildwheel.
		// * 33 has excessive buffering in the logcat client
		// (https://cs.android.com/android/_/android/platform/system/logging/+/d340721894f223327339010df59b0ac514308826).
		// * 34 consumes too much disk space on GitHub Actions (#142289).
		// * 35 has issues connecting to the internet (#142387).
		// * 36 and later are not available as aosp_atd images yet.
		targetSdk = 32

		versionCode = 1
		versionName = "1.0"
Expand DownExpand Up		@@ -130,9 +133,10 @@ android {
		path("src/main/c/CMakeLists.txt")
		}

		// Set this property to something non-empty, otherwise it'll use the default
		// list, which ignores asset directories beginning with an underscore.
		aaptOptions.ignoreAssetsPattern = ".git"
		// Set this property to something nonexistent but non-empty. Otherwise it'll use the
		// default list, which ignores asset directories beginning with an underscore, and
		// maybe also other files required by tests.
		aaptOptions.ignoreAssetsPattern = "android-testbed-dont-ignore-anything"

		compileOptions {
		sourceCompatibility = JavaVersion.VERSION_1_8
Expand DownExpand Up		@@ -234,6 +238,12 @@ androidComponents.onVariants { variant ->
		from(cwd)
		}
		}

		// A filename ending with .gz will be automatically decompressed
		// while building the APK. Avoid this by adding a dash to the end,
		// and add an extra dash to any filenames that already end with one.
		// This will be undone in MainActivity.kt.
		rename(""".*(\.gz\|-)""", "$0-")
		}
		}

Expand Down
Original file line number	Diff line number	Diff line change
Expand Up		@@ -80,7 +80,9 @@ class PythonTestRunner(val context: Context) {
		continue
		}
		input.use {
		File(targetSubdir, name).outputStream().use { output->
		// Undo the .gz workaround from build.gradle.kts.
		val outputName= name.replace(Regex("""(.*)-"""),"$1")
		File(targetSubdir, outputName).outputStream().use { output->
		input.copyTo(output)
		}
		}
Expand Down
Original file line number	Diff line number	Diff line change
Expand Up		@@ -168,6 +168,13 @@ def write(self, prio, tag, message):
		# message.
		message=message.replace(b"\x00",b"\xc0\x80")

		# On API level 30 and higher, Logcat will strip any number of leading
		# newlines. This is visible in all `logcat` modes, even --binary. Work
		# around this by adding a leading space, which shouldn't make any
		# difference to the log's usability.
		ifmessage.startswith(b"\n"):
		message=b" "+message

		withself._lock:
		now=time()
		self._bucket_level+= (
Expand Down
Original file line number	Diff line number	Diff line change
		@@ -1,5 +1,4 @@
		importio
		importplatform
		importqueue
		importre
		importsubprocess
Expand All		@@ -17,8 +16,6 @@
		ifsys.platform!="android":
		raiseunittest.SkipTest("Android-specific")

		api_level=platform.android_ver().api_level

		# (name, level, fileno)
		STREAM_INFO= [("stdout","I",1), ("stderr","W",2)]

Expand DownExpand Up		@@ -179,14 +176,18 @@ def write(s, lines=None, *, write_len=None):

		# Multi-line messages. Avoid identical consecutive lines, as
		# they may activate "chatty" filtering and break the tests.
		write("\nx", [""])
		#
		# Additional spaces will appear in the output where necessary to
		# protect leading newlines.
		write("\nx", [" "])
		write("\na\n", ["x","a"])
		write("\n", [""])
		write("\n", [" "])
		write("\n\n", [" "," "])
		write("b\n", ["b"])
		write("c\n\n", ["c",""])
		write("c\n\n", ["c",""])
		write("d\ne", ["d"])
		write("xx", [])
		write("f\n\ng", ["exxf",""])
		write("f\n\ng", ["exxf",""])
		write("\n", ["g"])

		# Since this is a line-based logging system, line buffering
Expand All		@@ -197,15 +198,16 @@ def write(s, lines=None, *, write_len=None):
		# However, buffering can be turned off completely if you want a
		# flush after every write.
		withself.reconfigure(stream,write_through=True):
		write("\nx", ["","x"])
		write("\na\n", ["","a"])
		write("\n", [""])
		write("\nx", [" ","x"])
		write("\na\n", [" ","a"])
		write("\n", [" "])
		write("\n\n", [" "," "])
		write("b\n", ["b"])
		write("c\n\n", ["c",""])
		write("c\n\n", ["c",""])
		write("d\ne", ["d","e"])
		write("xx", ["xx"])
		write("f\n\ng", ["f","","g"])
		write("\n", [""])
		write("f\n\ng", ["f","","g"])
		write("\n", [""])

		# "\r\n" should be translated into "\n".
		write("hello\r\n", ["hello"])
Expand DownExpand Up		@@ -325,19 +327,16 @@ def write(b, lines=None, *, write_len=None):
		# currently use `logcat -v tag`, which shows each line as if it
		# was a separate log entry, but strips a single trailing
		# newline.
		#
		# On newer versions of Android, all three of the above tools (or
		# maybe Logcat itself) will also strip any number of leading
		# newlines.
		write(b"\nx", ["","x"]ifapi_level<30else ["x"])
		write(b"\na\n", ["","a"]ifapi_level<30else ["a"])
		write(b"\n", [""])
		write(b"\nx", [" ","x"])
		write(b"\na\n", [" ","a"])
		write(b"\n", [" "])
		write(b"\n\n", [" ",""])
		write(b"b\n", ["b"])
		write(b"c\n\n", ["c",""])
		write(b"d\ne", ["d","e"])
		write(b"xx", ["xx"])
		write(b"f\n\ng", ["f","","g"])
		write(b"\n", [""])
		write(b"\n", [""])

		# "\r\n" should be translated into "\n".
		write(b"hello\r\n", ["hello"])
Expand Down
Original file line number	Diff line number	Diff line change
		@@ -0,0 +1,3 @@
		The Android testbed now distinguishes between stdout/stderr messages which
		were triggered by a newline, and those triggered by a manual call to
		``flush``. This fixes logging of progress indicators and similar content.