manual_unwrap_or / use consts::constant_simple helper

clippy_lints/src/manual_unwrap_or.rs

@@ -1,3 +1,4 @@
+use crate::consts::constant_simple;
 use crate::utils;
 use if_chain::if_chain;
 use rustc_errors::Applicability;
@@ -18,15 +19,17 @@ declare_clippy_lint! {
  ///
  /// **Example:**
  /// ```rust
- /// match int_option {
+ /// let foo: Option<Int> = None;
+ /// match foo {
  /// Some(v) => v,
  /// None => 1,
- /// }
+ /// };
  /// ```
  ///
  /// Use instead:
  /// ```rust
- /// int_option.unwrap_or(1)
+ /// let foo: Option<Int> = None;
+ /// foo.unwrap_or(1);
  /// ```
  pub MANUAL_UNWRAP_OR,
  complexity,
@@ -84,7 +87,7 @@ fn lint_option_unwrap_or_case<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'tc
  then {
  let reindented_none_body =
  utils::reindent_multiline(none_body_snippet.into(), true, Some(indent));
- let eager_eval = utils::eager_or_lazy::is_eagerness_candidate(cx, none_arm.body);
+ let eager_eval = constant_simple(cx, cx.typeck_results(), none_arm.body).is_some();
  let method = if eager_eval {
  "unwrap_or"
  } else {

tests/ui/manual_unwrap_or.fixed

@@ -9,7 +9,7 @@ fn unwrap_or() {
  Some(1).unwrap_or(42);
 
  // richer none expr
- Some(1).unwrap_or_else(|| 1 + 42);
+ Some(1).unwrap_or(1 + 42);
 
  // multiline case
  Some(1).unwrap_or_else(|| {

tests/ui/manual_unwrap_or.stderr

@@ -18,14 +18,14 @@ LL | | Some(i) => i,
 LL | | };
  | |_____^ help: replace with: `Some(1).unwrap_or(42)`
 
-error: this pattern reimplements `Option::unwrap_or_else`
+error: this pattern reimplements `Option::unwrap_or`
  --> $DIR/manual_unwrap_or.rs:18:5
  |
 LL | / match Some(1) {
 LL | | Some(i) => i,
 LL | | None => 1 + 42,
 LL | | };
- | |_____^ help: replace with: `Some(1).unwrap_or_else(|| 1 + 42)`
+ | |_____^ help: replace with: `Some(1).unwrap_or(1 + 42)`
 
 error: this pattern reimplements `Option::unwrap_or_else`
  --> $DIR/manual_unwrap_or.rs:24:5