Our product currently spans a large number of technologies, including Java, PL/SQL, VB.Net and ABAP. We have a fairly mature source control and build system set up for all of the languages except ABAP, which is still in the stone ages. Since SAP has a build system set up within it, our engineers do all of their development in an SAP environment export transports, and check those into source control. Since we support a number of SAP versions, it becomes very difficult to track versions and migrate code across 4.6, 4.7, 5.0, etc.
My ideal process would be to check the ABAP code into source control in text files, and then load it into SAP and generate the transports as part of the build process. The SAP engineers don't think there are tools to support this model.
If you are managing ABAP code in a source control system, what does your process look like? Are there tools available (preferably command-line) for loading ABAP code into SAP? How do your engineers manage the code/test/debug cycle? Do they code in SAP and then export the code when finished, or edit in an external editor?