Skip to content

Commit

Permalink
Merge pull request #2503 from digit-google/fix-output-regression
Browse files Browse the repository at this point in the history
Fix #2499: Status update regression.
  • Loading branch information
jhasse authored Oct 1, 2024
2 parents 6a31acc + 562cee1 commit 4c59ee0
Show file tree
Hide file tree
Showing 2 changed files with 109 additions and 29 deletions.
92 changes: 85 additions & 7 deletions misc/output_test.py
Original file line number Diff line number Diff line change
Expand Up @@ -39,8 +39,29 @@ def run(
self,
flags: str = '',
pipe: bool = False,
raw_output: bool = False,
env: Dict[str, str] = default_env,
) -> str:
"""Run Ninja command, and get filtered output.
Args:
flags: Extra arguments passed to Ninja.
pipe: set to True to run Ninja in a non-interactive terminal.
If False (the default), this runs Ninja in a pty to simulate
a smart terminal (this feature cannot work on Windows!).
raw_output: set to True to return the raw, unfiltered command
output.
env: Optional environment dictionary to run the command in.
Returns:
A UTF-8 string corresponding to the output (stdout only) of the
Ninja command. By default, partial lines that were overwritten
are removed according to the rules described in the comments
below.
"""
ninja_cmd = '{} {}'.format(NINJA_PATH, flags)
try:
if pipe:
Expand All @@ -55,21 +76,55 @@ def run(
except subprocess.CalledProcessError as err:
sys.stdout.buffer.write(err.output)
raise err
final_output = ''
for line in output.decode('utf-8').splitlines(True):
if len(line) > 0 and line[-1] == '\r':
continue
final_output += line.replace('\r', '')
return final_output

if raw_output:
return output.decode('utf-8')

# When running in a smart terminal, Ninja uses CR (\r) to
# return the cursor to the start of the current line, prints
# something, then uses `\x1b[K` to clear everything until
# the end of the line.
#
# Thus printing 'FOO', 'BAR', 'ZOO' on the same line, then
# jumping to the next one results in the following output
# on Posix:
#
# '\rFOO\x1b[K\rBAR\x1b[K\rZOO\x1b[K\r\n'
#
# The following splits the output at both \r, \n and \r\n
# boundaries, which gives:
#
# [ '\r', 'FOO\x1b[K\r', 'BAR\x1b[K\r', 'ZOO\x1b[K\r\n' ]
#
decoded_lines = output.decode('utf-8').splitlines(True)

# Remove any item that ends with a '\r' as this means its
# content will be overwritten by the next item in the list.
# For the previous example, this gives:
#
# [ 'ZOO\x1b[K\r\n' ]
#
final_lines = [ l for l in decoded_lines if not l.endswith('\r') ]

# Return a single string that concatenates all filtered lines
# while removing any remaining \r in it. Needed to transform
# \r\n into \n.
#
# "ZOO\x1b[K\n'
#
return ''.join(final_lines).replace('\r', '')

def run(
build_ninja: str,
flags: str = '',
pipe: bool = False,
raw_output: bool = False,
env: Dict[str, str] = default_env,
) -> str:
"""Run Ninja with a given build plan in a temporary directory.
"""
with BuildDir(build_ninja) as b:
return b.run(flags, pipe, env)
return b.run(flags, pipe, raw_output, env)

@unittest.skipIf(platform.system() == 'Windows', 'These test methods do not work on Windows')
class Output(unittest.TestCase):
Expand Down Expand Up @@ -149,6 +204,29 @@ def test_issue_1966(self) -> None:
'''[1/1] cat cat.rsp cat.rsp > a\x1b[K
''')

def test_issue_2499(self) -> None:
# This verifies that Ninja prints its status line updates on a single
# line when running in a smart terminal, and when commands do not have
# any output. Get the raw command output which includes CR (\r) codes
# and all content that was printed by Ninja.
self.assertEqual(run(
'''rule touch
command = touch $out
build foo: touch
build bar: touch foo
build zoo: touch bar
''', flags='-j1 zoo', raw_output=True).split('\r'),
[
'',
'[0/3] touch foo\x1b[K',
'[1/3] touch foo\x1b[K',
'[1/3] touch bar\x1b[K',
'[2/3] touch bar\x1b[K',
'[2/3] touch zoo\x1b[K',
'[3/3] touch zoo\x1b[K',
'\n',
])

def test_pr_1685(self) -> None:
# Running those tools without .ninja_deps and .ninja_log shouldn't fail.
Expand Down
46 changes: 24 additions & 22 deletions src/status_printer.cc
Original file line number Diff line number Diff line change
Expand Up @@ -216,34 +216,36 @@ void StatusPrinter::BuildEdgeFinished(Edge* edge, int64_t start_time_millis,
printer_.PrintOnNewLine(edge->EvaluateCommand() + "\n");
}

if (!output.empty()) {
#ifdef _WIN32
// Fix extra CR being added on Windows, writing out CR CR LF (#773)
fflush(stdout); // Begin Windows extra CR fix
_setmode(_fileno(stdout), _O_BINARY);
// Fix extra CR being added on Windows, writing out CR CR LF (#773)
fflush(stdout); // Begin Windows extra CR fix
_setmode(_fileno(stdout), _O_BINARY);
#endif

// ninja sets stdout and stderr of subprocesses to a pipe, to be able to
// check if the output is empty. Some compilers, e.g. clang, check
// isatty(stderr) to decide if they should print colored output.
// To make it possible to use colored output with ninja, subprocesses should
// be run with a flag that forces them to always print color escape codes.
// To make sure these escape codes don't show up in a file if ninja's output
// is piped to a file, ninja strips ansi escape codes again if it's not
// writing to a |smart_terminal_|.
// (Launching subprocesses in pseudo ttys doesn't work because there are
// only a few hundred available on some systems, and ninja can launch
// thousands of parallel compile commands.)
if (printer_.supports_color() || output.find('\x1b') == std::string::npos) {
printer_.PrintOnNewLine(output);
} else {
std::string final_output = StripAnsiEscapeCodes(output);
printer_.PrintOnNewLine(final_output);
}
// ninja sets stdout and stderr of subprocesses to a pipe, to be able to
// check if the output is empty. Some compilers, e.g. clang, check
// isatty(stderr) to decide if they should print colored output.
// To make it possible to use colored output with ninja, subprocesses should
// be run with a flag that forces them to always print color escape codes.
// To make sure these escape codes don't show up in a file if ninja's output
// is piped to a file, ninja strips ansi escape codes again if it's not
// writing to a |smart_terminal_|.
// (Launching subprocesses in pseudo ttys doesn't work because there are
// only a few hundred available on some systems, and ninja can launch
// thousands of parallel compile commands.)
if (printer_.supports_color() || output.find('\x1b') == std::string::npos) {
printer_.PrintOnNewLine(output);
} else {
std::string final_output = StripAnsiEscapeCodes(output);
printer_.PrintOnNewLine(final_output);
}

#ifdef _WIN32
fflush(stdout);
_setmode(_fileno(stdout), _O_TEXT); // End Windows extra CR fix
fflush(stdout);
_setmode(_fileno(stdout), _O_TEXT); // End Windows extra CR fix
#endif
}
}

void StatusPrinter::BuildStarted() {
Expand Down

0 comments on commit 4c59ee0

Please sign in to comment.