bpo-21862: Add -m option to cProfile for profiling modules (#4297)

* bpo-21862: Add -m option to cProfile for profiling modules

1 files changed, 23 insertions, 12 deletions

diff --git a/Lib/cProfile.py b/Lib/cProfile.py
index 1184385..f166a1c 100755
--- a/Lib/cProfile.py
+++ b/Lib/cProfile.py
@@ -121,9 +121,11 @@ def label(code):
 # ____________________________________________________________
 
 def main():
-    import os, sys
+    import os
+    import sys
+    import runpy
     from optparse import OptionParser
-    usage = "cProfile.py [-o output_file_path] [-s sort] scriptfile [arg] ..."
+    usage = "cProfile.py [-o output_file_path] [-s sort] [-m module | scriptfile] [arg] ..."
     parser = OptionParser(usage=usage)
     parser.allow_interspersed_args = False
     parser.add_option('-o', '--outfile', dest="outfile",
@@ -131,6 +133,8 @@ def main():
     parser.add_option('-s', '--sort', dest="sort",
         help="Sort order when printing to stdout, based on pstats.Stats class",
         default=-1)
+    parser.add_option('-m', dest="module", action="store_true",
+        help="Profile a library module", default=False)
 
     if not sys.argv[1:]:
         parser.print_usage()
@@ -140,16 +144,23 @@ def main():
     sys.argv[:] = args
 
     if len(args) > 0:
-        progname = args[0]
-        sys.path.insert(0, os.path.dirname(progname))
-        with open(progname, 'rb') as fp:
-            code = compile(fp.read(), progname, 'exec')
-        globs = {
-            '__file__': progname,
-            '__name__': '__main__',
-            '__package__': None,
-            '__cached__': None,
-        }
+        if options.module:
+            code = "run_module(modname, run_name='__main__')"
+            globs = {
+                'run_module': runpy.run_module,
+                'modname': args[0]
+            }
+        else:
+            progname = args[0]
+            sys.path.insert(0, os.path.dirname(progname))
+            with open(progname, 'rb') as fp:
+                code = compile(fp.read(), progname, 'exec')
+            globs = {
+                '__file__': progname,
+                '__name__': '__main__',
+                '__package__': None,
+                '__cached__': None,
+            }
         runctx(code, globs, None, options.outfile, options.sort)
     else:
         parser.print_usage()