# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1214061803 -7200
# Node ID 7b78ddb23be648e1799342739b7a1ff6410285b2
# Parent  de8cd27e721d58cd12225a287116b49c23b5d7df
Added support for the detection of module attribute assignment.
Added some more tests of module assignment.
Introduced better system path initialisation based on the program being
inspected.

diff -r de8cd27e721d -r 7b78ddb23be6 docs/rationale.txt
--- a/docs/rationale.txt	Mon Jun 16 01:56:46 2008 +0200
+++ b/docs/rationale.txt	Sat Jun 21 17:23:23 2008 +0200
@@ -7,8 +7,9 @@
 Motivations
 
   * Run Python programs in "small" devices
-  * Small programs
-  * Few executed instructions
+  * Small programs plus few executed instructions
+    * Avoid expensive library code
+      (small footprint, lots of executed instructions)
 
 Python's flexibility comes at a cost
 
@@ -17,6 +18,13 @@
   * Difficult to predict eventual behaviour before execution
   * Difficult to generate optimisations when compiling
 
+Not all things are dynamic/equal in Python
+
+  * Locals, modules and classes are special in some way
+    * Locals don't tend to change unilaterally
+    * Modules usually retain their identity
+    * Classes differ from objects (despite metaclasses)
+
 Attribute access
 
   * Must do a full lookup every time:
@@ -34,7 +42,7 @@
 
 Consequences of revised attribute access
 
-  * Cannot extend the range of attributes on objects
+  * Cannot extend the range of attributes on objects of existing classes
   * Further optimisations:
     * Restriction: attempt to control modification of attributes
     * Result: further optimisation of accesses
diff -r de8cd27e721d -r 7b78ddb23be6 micropython/inspect.py
--- a/micropython/inspect.py	Mon Jun 16 01:56:46 2008 +0200
+++ b/micropython/inspect.py	Sat Jun 21 17:23:23 2008 +0200
@@ -173,9 +173,26 @@
 
         self.all_objects.add(obj)
 
+    def store_module_attr(self, name, module):
+
+        """
+        Record module attribute 'name' in the given 'module' using the current
+        expression.
+        """
+
+        if isinstance(self.expr, Attr):
+            assigned_value = self.expr.value
+        else:
+            assigned_value = self.expr
+
+        module.set(name, assigned_value, 0)
+
     def store_class_attr(self, name):
 
-        "Record class attribute 'name' in the current class."
+        """
+        Record class attribute 'name' in the current class using the current
+        expression.
+        """
 
         if self.in_method and self.namespaces[-2].has_key(name):
 
@@ -300,9 +317,13 @@
 
     def visitAssAttr(self, node):
         expr = self.dispatch(node.expr)
-        if isinstance(expr, Attr) and expr.name == "self":
-            if not self.store_class_attr(node.attrname):
-                self.store_instance_attr(node.attrname)
+        if isinstance(expr, Attr):
+            if expr.name == "self":
+                if not self.store_class_attr(node.attrname):
+                    self.store_instance_attr(node.attrname)
+            elif isinstance(expr.value, Module):
+                self.store_module_attr(node.attrname, expr.value)
+                print "Warning: attribute %r of module %r set outside the module." % (node.attrname, expr.value.name)
         return None
 
     def visitAssList(self, node):
diff -r de8cd27e721d -r 7b78ddb23be6 test.py
--- a/test.py	Mon Jun 16 01:56:46 2008 +0200
+++ b/test.py	Sat Jun 21 17:23:23 2008 +0200
@@ -4,6 +4,7 @@
 from micropython.rsvp import raw
 import rsvp
 import sys
+import os
 
 code = None
 
@@ -32,7 +33,15 @@
 
 if __name__ == "__main__":
     args = sys.argv[2:]
-    i = micropython.Importer(sys.path, "-v" in args)
+    path = sys.path[:]
+
+    if len(sys.argv) > 1:
+        program = os.path.abspath(sys.argv[1])
+        path.append(os.path.split(program)[0])
+    else:
+        program = None
+
+    i = micropython.Importer(path, "-v" in args)
 
     if "-omax" in args:
         requested_optimisations = i.supported_optimisations
@@ -45,11 +54,12 @@
 
     try:
         builtins = i.load_from_file("lib/builtins.py", "__builtins__")
-        if len(sys.argv) < 2:
+        if program is None:
+            print "Loading module micropython ..."
             m = i.load("micropython")
-            #m = i.load_from_file("micropython/__init__.py")
         else:
-            m = i.load_from_file(sys.argv[1])
+            print "Loading program", program, "..."
+            m = i.load_from_file(program)
     except micropython.ProcessingError, exc:
         print repr(exc)
     else:
diff -r de8cd27e721d -r 7b78ddb23be6 tests/failure/imported.py
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/tests/failure/imported.py	Sat Jun 21 17:23:23 2008 +0200
@@ -0,0 +1,6 @@
+#!/usr/bin/env python
+
+attr = 123
+a = 10
+
+# vim: tabstop=4 expandtab shiftwidth=4
diff -r de8cd27e721d -r 7b78ddb23be6 tests/failure/importer.py
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/tests/failure/importer.py	Sat Jun 21 17:23:23 2008 +0200
@@ -0,0 +1,18 @@
+#!/usr/bin/env python
+
+import imported
+
+imported.attr = 456 # detected with warning
+
+m = imported
+imported.a = 9      # detected with warning
+m.a = 8             # detected with warning (m is always imported)
+
+imported.x = 1      # detected with warning (despite no collision)
+
+n = None
+n = imported
+n.y = 2             # not detected due to reassignment of n
+n.y = 3             # not detected due to reassignment of n
+
+# vim: tabstop=4 expandtab shiftwidth=4