Import bug - Circular Dependencies #100
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boukeversteegh
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… is flattened into two python packages
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Protobuf itself does not allow circular dependencies (
import "a.proto"inb.proto, andimport "b.proto"ina.proto).So why do we still get circular import errors in python? Because protobuf dependencies are on file-level, while betterproto dependencies are on package-level.
Example:
The proto messages depend on each other in a non-circular way:
Test and RootPackageMessage are in different files, but belong to the same package (root):
After grouping the packages into single files or modules, a circular dependency is created:
Because we don't know in advance which imports will cause a circular-dependency (as we currently do single-pass compiling), the only solution I see is to always use forward references (
"package.SomeType"), and have the import statements at the bottom.This PR implements that solution.