SCons
Configure() called from a builder or scanner
This issue was originally created at: 2008-09-17 23:35:10.
This issue was reported by: gregnoel.
gregnoel said at 2008-09-17 23:35:10
This code appears twice in Script/SConscript.py:
if not SCons.Script.sconscript_reading:
raise SCons.Errors.UserError, "Calling Configure from Builders is not supported."
What this code says is, if we're not reading a SConscript, complain that you can't use Configure() inside a Builder.
Er, on the one hand, if you're not reading a SConscript, you're not running a Builder, so the message is clearly wrong. My guess is that this message is intended be triggered inside a Scanner.
On the other hand, it clearly is a bad idea to invoke Configure from a Builder, so there should be some way of detecting that and generating an error.
My suggestion would be that the wrappers for Builders and Scanners should each increment a variable before they call the actual builder/scanner and decrement it when the builder/scanner returns. This error message should be keyed off of those variables.
Oh, and all that logic should be moved out of Script/* and into some core file (maybe SConf.py?). Calling Configure() from a builder or scanner is a bad idea in general, not just when the builder or scanner is in a SConscript file.
gregnoel said at 2008-09-25 01:20:51
Bug party triage.
Interesting. The comment is correct. There's no guarantee that you are calling it from a builder, only that you are calling it outside of processing the SConscript/SConstruct/associated logic.
So maybe Calling Configure from invalid context. You can only call Configure from SConstruct/SConscript/Associated logic processing ?