src/tools/clippy/clippy_lints/src/wildcard_dependencies.rs

   1 use clippy_utils::{diagnostics::span_lint, is_lint_allowed};
   2 use rustc_hir::{hir_id::CRATE_HIR_ID, Crate};
   3 use rustc_lint::{LateContext, LateLintPass};
   4 use rustc_session::{declare_lint_pass, declare_tool_lint};
   5 use rustc_span::source_map::DUMMY_SP;
   6
   7 use if_chain::if_chain;
   8
   9 declare_clippy_lint! {
  10     /// ### What it does
  11     /// Checks for wildcard dependencies in the `Cargo.toml`.
  12     ///
  13     /// ### Why is this bad?
  14     /// [As the edition guide says](https://rust-lang-nursery.github.io/edition-guide/rust-2018/cargo-and-crates-io/crates-io-disallows-wildcard-dependencies.html),
  15     /// it is highly unlikely that you work with any possible version of your dependency,
  16     /// and wildcard dependencies would cause unnecessary breakage in the ecosystem.
  17     ///
  18     /// ### Example
  19     /// ```toml
  20     /// [dependencies]
  21     /// regex = "*"
  22     /// ```
  23     pub WILDCARD_DEPENDENCIES,
  24     cargo,
  25     "wildcard dependencies being used"
  26 }
  27
  28 declare_lint_pass!(WildcardDependencies => [WILDCARD_DEPENDENCIES]);
  29
  30 impl LateLintPass<'_> for WildcardDependencies {
  31     fn check_crate(&mut self, cx: &LateContext<'_>, _: &Crate<'_>) {
  32         if is_lint_allowed(cx, WILDCARD_DEPENDENCIES, CRATE_HIR_ID) {
  33             return;
  34         }
  35
  36         let metadata = unwrap_cargo_metadata!(cx, WILDCARD_DEPENDENCIES, false);
  37
  38         for dep in &metadata.packages[0].dependencies {
  39             // VersionReq::any() does not work
  40             if_chain! {
  41                 if let Ok(wildcard_ver) = semver::VersionReq::parse("*");
  42                 if let Some(ref source) = dep.source;
  43                 if !source.starts_with("git");
  44                 if dep.req == wildcard_ver;
  45                 then {
  46                     span_lint(
  47                         cx,
  48                         WILDCARD_DEPENDENCIES,
  49                         DUMMY_SP,
  50                         &format!("wildcard dependency for `{}`", dep.name),
  51                     );
  52                 }
  53             }
  54         }
  55     }
  56 }