Comprehensive refactoring is missing in Flex Builder: currently you can only rename local variables and class members, but not package names.  So if you move a folder, you have to manually edit all the package names.  Lame.

This python script fixes all package names in a root source folder.  It assumes the folders are the correct package names.

! /usr/bin/env python

"""
Repairs actionscript package names, since Flex Builder is too crummy to do this simple task.
"""
import os.path, string, sys, glob, re

pattern = re.compile('^\spackage .')

if len(sys.argv) == 1:
    print "Usage: fixAS3PackageNames.py [src folder]"
    print "Repairs actionscript source package names"
    sys.exit(0)

path = sys.argv[1]

path = os.path.join(path, "")

def packageFromFileName (fileName):
    tokens = fileName.strip().split("/")[0:-1]
    return string.join(tokens, ".")

fileSet = set() 

for root, dirs, files in os.walk(path):
    for fileName in files:
        if fileName.endswith(".as"):
            fileSet.add( os.path.join( root[len(path):], fileName ))

for fileName in fileSet:
    correctedFileName = os.path.join(path, fileName)
    f = open(correctedFileName, 'r')
    lines = f.readlines()
    f.close()

write = False
for i in range(len(lines)):
    line = lines[i]
    if pattern.match(line):
        packageString = line.split("package")[-1].strip()
        filePackage = packageFromFileName(fileName)

        if packageString != filePackage:
            write = True
            lines[i] = "package " + filePackage

            if line.find("{") >= 0:
                lines[i] = lines[i] + "{"
            if line[-1] == "\n":
                lines[i] = lines[i] + "\n"
                print fileName +": " + packageString + " -> " + filePackage
        break
if write:
    f = open(correctedFileName, 'w')
    for line in lines:
        f.write(line)
    f.close()