trace — 跟随程序流

Example Program

# trace_example/main.py
from recurse import recurse


def main():
    print('This is the main program.')
    recurse(2)


if __name__ == '__main__':
    main()

Tracing Execution

$ python3 -m trace --ignore-dir=.../lib/python3.6 \
--trace trace_example/main.py

 --- modulename: main, funcname: <module>
main.py(7): """
main.py(10): from recurse import recurse
 --- modulename: recurse, funcname: <module>
recurse.py(7): """
recurse.py(11): def recurse(level):
recurse.py(17): def not_called():
main.py(13): def main():
main.py(18): if __name__ == '__main__':
main.py(19):     main()
 --- modulename: main, funcname: main
main.py(14):     print('This is the main program.')
This is the main program.
main.py(15):     recurse(2)
 --- modulename: recurse, funcname: recurse
recurse.py(12):     print('recurse({})'.format(level))
recurse(2)
recurse.py(13):     if level:
recurse.py(14):         recurse(level - 1)
 --- modulename: recurse, funcname: recurse
recurse.py(12):     print('recurse({})'.format(level))
recurse(1)
recurse.py(13):     if level:
recurse.py(14):         recurse(level - 1)
 --- modulename: recurse, funcname: recurse
recurse.py(12):     print('recurse({})'.format(level))
recurse(0)
recurse.py(13):     if level:
 --- modulename: trace, funcname: _unsettrace
trace.py(77):         sys.settrace(None)

Code Coverage

$ python3 -m trace --count trace_example/main.py

This is the main program.
recurse(2)
recurse(1)
recurse(0)

from recurse import recurse

def main():
    print 'This is the main program.'
    recurse(2)
    return

if __name__ == '__main__':
    main()

def recurse(level):
    print 'recurse(%s)' % level
    if level:
        recurse(level-1)
    return

def not_called():
    print 'This function is never called.'

Programming Interface

# trace_run.py
import trace
from trace_example.recurse import recurse

tracer = trace.Trace(count=False, trace=True)
tracer.run('recurse(2)')

Saving Result Data

# trace_CoverageResults.py
import trace
from trace_example.recurse import recurse

tracer = trace.Trace(count=True, trace=False)
tracer.runfunc(recurse, 2)

results = tracer.results()
results.write_results(coverdir='coverdir2')

# trace_report.py
import trace
from trace_example.recurse import recurse

tracer = trace.Trace(count=True,
                     trace=False,
                     outfile='trace_report.dat')
tracer.runfunc(recurse, 2)

report_tracer = trace.Trace(count=False,
                            trace=False,
                            infile='trace_report.dat')
results = tracer.results()
results.write_results(summary=True, coverdir='/tmp')