| //! lint on multiple versions of a crate being used |
| |
| use crate::utils::span_lint; |
| use rustc::lint::{EarlyContext, EarlyLintPass, LintArray, LintPass}; |
| use rustc::{declare_tool_lint, lint_array}; |
| use syntax::{ast::*, source_map::DUMMY_SP}; |
| |
| use cargo_metadata; |
| use itertools::Itertools; |
| |
| declare_clippy_lint! { |
| /// **What it does:** Checks to see if multiple versions of a crate are being |
| /// used. |
| /// |
| /// **Why is this bad?** This bloats the size of targets, and can lead to |
| /// confusing error messages when structs or traits are used interchangeably |
| /// between different versions of a crate. |
| /// |
| /// **Known problems:** Because this can be caused purely by the dependencies |
| /// themselves, it's not always possible to fix this issue. |
| /// |
| /// **Example:** |
| /// ```toml |
| /// # This will pull in both winapi v0.3.4 and v0.2.8, triggering a warning. |
| /// [dependencies] |
| /// ctrlc = "3.1.0" |
| /// ansi_term = "0.11.0" |
| /// ``` |
| pub MULTIPLE_CRATE_VERSIONS, |
| cargo, |
| "multiple versions of the same crate being used" |
| } |
| |
| pub struct Pass; |
| |
| impl LintPass for Pass { |
| fn get_lints(&self) -> LintArray { |
| lint_array!(MULTIPLE_CRATE_VERSIONS) |
| } |
| |
| fn name(&self) -> &'static str { |
| "MultipleCrateVersions" |
| } |
| } |
| |
| impl EarlyLintPass for Pass { |
| fn check_crate(&mut self, cx: &EarlyContext<'_>, _: &Crate) { |
| let metadata = if let Ok(metadata) = cargo_metadata::MetadataCommand::new().exec() { |
| metadata |
| } else { |
| span_lint(cx, MULTIPLE_CRATE_VERSIONS, DUMMY_SP, "could not read cargo metadata"); |
| |
| return; |
| }; |
| |
| let mut packages = metadata.packages; |
| packages.sort_by(|a, b| a.name.cmp(&b.name)); |
| |
| for (name, group) in &packages.into_iter().group_by(|p| p.name.clone()) { |
| let group: Vec<cargo_metadata::Package> = group.collect(); |
| |
| if group.len() > 1 { |
| let versions = group.into_iter().map(|p| p.version).join(", "); |
| |
| span_lint( |
| cx, |
| MULTIPLE_CRATE_VERSIONS, |
| DUMMY_SP, |
| &format!("multiple versions for dependency `{}`: {}", name, versions), |
| ); |
| } |
| } |
| } |
| } |