clippy_lints/src/wildcard_dependencies.rs

   1 use crate::utils::span_lint;
   2 use rustc::declare_lint_pass;
   3 use rustc::lint::{EarlyContext, EarlyLintPass, LintArray, LintPass};
   4 use rustc_session::declare_tool_lint;
   5 use syntax::{ast::*, source_map::DUMMY_SP};
   6
   7 use cargo_metadata;
   8 use if_chain::if_chain;
   9 use semver;
  10
  11 declare_clippy_lint! {
  12     /// **What it does:** Checks for wildcard dependencies in the `Cargo.toml`.
  13     ///
  14     /// **Why is this bad?** [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     /// **Known problems:** None.
  19     ///
  20     /// **Example:**
  21     ///
  22     /// ```toml
  23     /// [dependencies]
  24     /// regex = "*"
  25     /// ```
  26     pub WILDCARD_DEPENDENCIES,
  27     cargo,
  28     "wildcard dependencies being used"
  29 }
  30
  31 declare_lint_pass!(WildcardDependencies => [WILDCARD_DEPENDENCIES]);
  32
  33 impl EarlyLintPass for WildcardDependencies {
  34     fn check_crate(&mut self, cx: &EarlyContext<'_>, _: &Crate) {
  35         let metadata = if let Ok(metadata) = cargo_metadata::MetadataCommand::new().no_deps().exec() {
  36             metadata
  37         } else {
  38             span_lint(cx, WILDCARD_DEPENDENCIES, DUMMY_SP, "could not read cargo metadata");
  39             return;
  40         };
  41
  42         for dep in &metadata.packages[0].dependencies {
  43             // VersionReq::any() does not work
  44             if_chain! {
  45                 if let Ok(wildcard_ver) = semver::VersionReq::parse("*");
  46                 if let Some(ref source) = dep.source;
  47                 if !source.starts_with("git");
  48                 if dep.req == wildcard_ver;
  49                 then {
  50                     span_lint(
  51                         cx,
  52                         WILDCARD_DEPENDENCIES,
  53                         DUMMY_SP,
  54                         &format!("wildcard dependency for `{}`", dep.name),
  55                     );
  56                 }
  57             }
  58         }
  59     }
  60 }