src/tools/clippy/clippy_lints/src/create_dir.rs

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