Fix [env] in .cargo/config.toml overriding process environment variables#21995
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cargo_config_env() only checked extra_env (rust-analyzer.cargo.extraEnv) when deciding whether to skip an existing variable, but never checked the actual process environment via std::env::var. This caused config.toml values to unconditionally override real environment variables even without force = true, diverging from Cargo's behavior. Additionally, plain string entries (e.g. `KEY = "value"`) skipped the force check entirely. When a process env var takes precedence, its value is now inserted into the Env so that env!/option_env! resolution stays correct. Fixes rust-lang#21994
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Fixes #21994
cargo_config_env()only checkedextra_env(fromrust-analyzer.cargo.extraEnv) when deciding whether to skip an existing variable, but never checked the actual process environment viastd::env::var. This caused config.toml[env]values to unconditionally override real environment variables even withoutforce = true, diverging from Cargo's behavior.Additionally, plain string entries (e.g.
KEY = "value") skipped the force check entirely.The existing test used generic variable names like
CARGO_WORKSPACE_DIRandTESTwhich could collide with real process environment variables (rust-analyzer's own.cargo/config.tomlsetsCARGO_WORKSPACE_DIR). Renamed them to use theRA_TEST_prefix.