Make egg_info command write out setup requirements

This commit makes the egg_info command write out setup requirements as well
as install requirements, setup requirements are written to a
setup_requires.txt file.

The commit adds a new function write_setup_requirements which uses the
existing _write_requirements function to write setup requirements out to a file
and adds a new entry point to the egg_info.writers group.

1 files changed, 6 insertions, 0 deletions

diff --git a/setuptools/command/egg_info.py b/setuptools/command/egg_info.py
index 06764a17..78d86981 100755
--- a/setuptools/command/egg_info.py
+++ b/setuptools/command/egg_info.py
@@ -382,6 +382,12 @@ def write_requirements(cmd, basename, filename):
     cmd.write_or_delete_file("requirements", filename, data.getvalue())
 
 
+def write_setup_requirements(cmd, basename, filename):
+    data = StringIO()
+    _write_requirements(data, cmd.distribution.setup_requires)
+    cmd.write_or_delete_file("setup-requirements", filename, data.getvalue())
+
+
 def write_toplevel_names(cmd, basename, filename):
     pkgs = dict.fromkeys(
         [