Renamed 'dir' option to be consistent with other commands.

Don't call 'set_final_options()' in 'run()' anymore -- that's now
  guaranteed to be taken care of for us by the Distribution instance.
Rearranged to bit to allow outsiders (specifically, the 'dist' command)
  to find out what modules we would build:
  - 'find_modules()' renamed to 'find_package_modules()'
  - most of 'build_modules()' abstracted out to 'find_modules()'
  - added 'get_source_files()' (for the 'dist' command to use)
  - drastically simplified 'build_modules()' -- now just a wrapper around
    'find_modules()' and 'build_module()'

Lib/distutils/command/build_py.py

@@ -17,19 +17,19 @@ from distutils.util import mkpath, newer, make_file, copy_file
 
 class BuildPy (Command):
 
-    options = [('dir=', 'd', "directory for platform-shared files"),
+    options = [('build-dir=', 'd', "directory for platform-shared files"),
               ]
 
 
     def set_default_options (self):
-        self.dir = None
+        self.build_dir = None
         self.modules = None
         self.package = None
         self.package_dir = None
 
     def set_final_options (self):
         self.set_undefined_options ('build',
-                                    ('libdir', 'dir'))
+                                    ('build_lib', 'build_dir'))
 
         # Get the distribution options that are aliases for build_py
         # options -- list of packages and list of modules.
@@ -53,8 +53,6 @@ class BuildPy (Command):
         # metadata to know that a file is meant to be interpreted by
         # Python?)
 
-        self.set_final_options ()
-
         infiles = []
         outfiles = []
         missing = []
@@ -155,7 +153,7 @@ class BuildPy (Command):
     # check_module ()
 
 
-    def find_modules (self, package, package_dir):
+    def find_package_modules (self, package, package_dir):
         module_files = glob (os.path.join (package_dir, "*.py"))
         module_pairs = []
         for f in module_files:
@@ -164,36 +162,18 @@ class BuildPy (Command):
         return module_pairs
 
 
-    def build_module (self, module, module_file, package):
-
-        if type (package) is StringType:
-            package = string.split (package, '.')
-
-        # Now put the module source file into the "build" area -- this
-        # is easy, we just copy it somewhere under self.dir (the build
-        # directory for Python source).
-        outfile_path = package
-        outfile_path.append (module + ".py")
-        outfile_path.insert (0, self.dir)
-        outfile = apply (os.path.join, outfile_path)
-
-        dir = os.path.dirname (outfile)
-        self.mkpath (dir)
-        self.copy_file (module_file, outfile)
-
-
-    def build_modules (self):
-
+    def find_modules (self):
         # Map package names to tuples of useful info about the package:
         #    (package_dir, checked)
         # package_dir - the directory where we'll find source files for
         #   this package
         # checked - true if we have checked that the package directory
         #   is valid (exists, contains __init__.py, ... ?)
-
-
         packages = {}
 
+        # List of (module, package, filename) tuples to return
+        modules = []
+
         # We treat modules-in-packages almost the same as toplevel modules,
         # just the "package" for a toplevel is empty (either an empty
         # string or empty list, depending on context).  Differences:
@@ -202,7 +182,7 @@ class BuildPy (Command):
         for module in self.modules:
             path = string.split (module, '.')
             package = tuple (path[0:-1])
-            module = path[-1]
+            module_base = path[-1]
 
             try:
                 (package_dir, checked) = packages[package]
@@ -217,14 +197,65 @@ class BuildPy (Command):
             # XXX perhaps we should also check for just .pyc files
             # (so greedy closed-source bastards can distribute Python
             # modules too)
-            module_file = os.path.join (package_dir, module + ".py")
+            module_file = os.path.join (package_dir, module_base + ".py")
             if not self.check_module (module, module_file):
                 continue
 
+            modules.append ((module, package, module_file))
+
+        return modules
+
+    # find_modules ()
+
+
+    def get_source_files (self):
+
+        if self.modules:
+            modules = self.find_modules ()
+        else:
+            modules = []
+            for package in self.packages:
+                package_dir = self.get_package_dir (package)
+                m = self.find_package_modules (package, package_dir)
+                modules.extend (m)
+
+        # Both find_modules() and find_package_modules() return a list of
+        # tuples where the last element of each tuple is the filename --
+        # what a happy coincidence!
+        filenames = []
+        for module in modules:
+            filenames.append (module[-1])
+
+        return filenames                
+
+
+    def build_module (self, module, module_file, package):
+
+        if type (package) is StringType:
+            package = string.split (package, '.')
+
+        # Now put the module source file into the "build" area -- this is
+        # easy, we just copy it somewhere under self.build_dir (the build
+        # directory for Python source).
+        outfile_path = package
+        outfile_path.append (module + ".py")
+        outfile_path.insert (0, self.build_dir)
+        outfile = apply (os.path.join, outfile_path)
+
+        dir = os.path.dirname (outfile)
+        self.mkpath (dir)
+        self.copy_file (module_file, outfile)
+
+
+    def build_modules (self):
+
+        modules = self.find_modules()
+        for (module, package, module_file) in modules:
+
             # Now "build" the module -- ie. copy the source file to
-            # self.dir (the build directory for Python source).  (Actually,
-            # it gets copied to the directory for this package under
-            # self.dir.)
+            # self.build_dir (the build directory for Python source).
+            # (Actually, it gets copied to the directory for this package
+            # under self.build_dir.)
             self.build_module (module, module_file, package)
 
     # build_modules ()
@@ -242,10 +273,10 @@ class BuildPy (Command):
             # package!), and module_file is the path to the .py file,
             # relative to the current directory (ie. including
             # 'package_dir').
-            modules = self.find_modules (package, package_dir)
+            modules = self.find_package_modules (package, package_dir)
 
             # Now loop over the modules we found, "building" each one (just
-            # copy it to self.dir).
+            # copy it to self.build_dir).
             for (module, module_file) in modules:
                 self.build_module (module, module_file, package)