Minor versions do not support backwards compatibility

[MatthewLM]

Describe the bug

If the package version is specified using a caret in pubspec.yaml and the minor version is updated, an error will be produced similar to:

Bad state: flutter_rust_bridge's codegen version (2.6.0) should be the same as runtime version (2.7.0)

Minor version numbers should allow backwards compatibility if semantic versioning is followed.

Steps to reproduce

Self evident

Logs

No need for logs

Expected behavior

No response

Generated binding code

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OS

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Version of flutter_rust_bridge_codegen

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Flutter info

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Version of clang++

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Additional context

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[fzyzcjy]

It supports backward compatibility in the sense that, the user code should be able to run when upgrading from 2.6.0 to 2.7.0 without issues.

For your question, it is that you need to keep Rust flutter_rust_bridge in sync with Dart flutter_rust_bridge version. This is usually automatically done when running flutter_rust_bridge_codegen.

[MatthewLM]

I have library A that uses flutter_rust_bridge and produces a Rust binary with the codegen. I have library B that takes the binary and includes library A as a package in the pubspec.

The problem occurred when doing a dart pub upgrade for library B. The Rust binary was not updated, but the Dart flutter_rust_bridge package was. This caused library B to break. Library A cannot be expected to always keep up-to-date with flutter_rust_bridge with a new binary, so there will be a mismatch.

[fzyzcjy]

Totally agree that would be an issue. However, the cost to ensure different dart frb version is compatible with different rust frb version seems nontrivial, because this requires all internal implementation details change in a compatible way. What about using things like flutter_rust_bridge: 2.7.0 instead of ^2.7.0, does it disable dart pub upgrade from changing it?