clippy_lints/src/create_dir.rs

   1 use clippy_utils::diagnostics::span_lint_and_sugg;
   2 use clippy_utils::source::snippet;
   3 use clippy_utils::{match_def_path, paths};
   4 use if_chain::if_chain;
   5 use rustc_errors::Applicability;
   6 use rustc_hir::{Expr, ExprKind};
   7 use rustc_lint::{LateContext, LateLintPass};
   8 use rustc_session::{declare_lint_pass, declare_tool_lint};
   9
  10 declare_clippy_lint! {
  11     /// **What it does:** Checks usage of `std::fs::create_dir` and suggest using `std::fs::create_dir_all` instead.
  12     ///
  13     /// **Why is this bad?** Sometimes `std::fs::create_dir` is mistakenly chosen over `std::fs::create_dir_all`.
  14     ///
  15     /// **Known problems:** None.
  16     ///
  17     /// **Example:**
  18     ///
  19     /// ```rust
  20     /// std::fs::create_dir("foo");
  21     /// ```
  22     /// Use instead:
  23     /// ```rust
  24     /// std::fs::create_dir_all("foo");
  25     /// ```
  26     pub CREATE_DIR,
  27     restriction,
  28     "calling `std::fs::create_dir` instead of `std::fs::create_dir_all`"
  29 }
  30
  31 declare_lint_pass!(CreateDir => [CREATE_DIR]);
  32
  33 impl LateLintPass<'_> for CreateDir {
  34     fn check_expr(&mut self, cx: &LateContext<'_>, expr: &Expr<'_>) {
  35         if_chain! {
  36             if let ExprKind::Call(func, args) = expr.kind;
  37             if let ExprKind::Path(ref path) = func.kind;
  38             if let Some(def_id) = cx.qpath_res(path, func.hir_id).opt_def_id();
  39             if match_def_path(cx, def_id, &paths::STD_FS_CREATE_DIR);
  40             then {
  41                 span_lint_and_sugg(
  42                     cx,
  43                     CREATE_DIR,
  44                     expr.span,
  45                     "calling `std::fs::create_dir` where there may be a better way",
  46                     "consider calling `std::fs::create_dir_all` instead",
  47                     format!("create_dir_all({})", snippet(cx, args[0].span, "..")),
  48                     Applicability::MaybeIncorrect,
  49                 )
  50             }
  51         }
  52     }
  53 }