Auto merge of #81035 - JohnTitor:rollup-9m03awf, r=JohnTitor

Rollup of 5 pull requests

Successful merges:

 - #80254 (Don't try to add nested predicate to Rustdoc auto-trait `ParamEnv`)
 - #80834 (Remove unreachable panics from VecDeque::{front/back}[_mut])
 - #80944 (Use Option::map_or instead of `.map(..).unwrap_or(..)`)
 - #81008 (Don't ICE when computing a layout of a generator tainted by errors)
 - #81023 (Remove doctree::Variant)

Failed merges:

 - #81033 (Remove useless `clean::Variant` struct)

r? `@ghost`
`@rustbot` modify labels: rollup

2 files changed, 3 insertions, 3 deletions

diff --git a/compiler/rustc_span/src/source_map.rs b/compiler/rustc_span/src/source_map.rs
index 842ccda6ea8..4e0ce0d344d 100644
--- a/compiler/rustc_span/src/source_map.rs
+++ b/compiler/rustc_span/src/source_map.rs
@@ -539,7 +539,7 @@ impl SourceMap {
 
     pub fn is_line_before_span_empty(&self, sp: Span) -> bool {
         match self.span_to_prev_source(sp) {
-            Ok(s) => s.split('\n').last().map(|l| l.trim_start().is_empty()).unwrap_or(false),
+            Ok(s) => s.split('\n').last().map_or(false, |l| l.trim_start().is_empty()),
             Err(_) => false,
         }
     }
@@ -568,7 +568,7 @@ impl SourceMap {
         // asserting that the line numbers here are all indeed 1-based.
         let hi_line = hi.line.saturating_sub(1);
         for line_index in lo.line.saturating_sub(1)..hi_line {
-            let line_len = lo.file.get_line(line_index).map(|s| s.chars().count()).unwrap_or(0);
+            let line_len = lo.file.get_line(line_index).map_or(0, |s| s.chars().count());
             lines.push(LineInfo { line_index, start_col, end_col: CharPos::from_usize(line_len) });
             start_col = CharPos::from_usize(0);
         }
diff --git a/compiler/rustc_span/src/source_map/tests.rs b/compiler/rustc_span/src/source_map/tests.rs
index b8459eee4ec..3f22829b049 100644
--- a/compiler/rustc_span/src/source_map/tests.rs
+++ b/compiler/rustc_span/src/source_map/tests.rs
@@ -107,7 +107,7 @@ fn t7() {
 fn span_from_selection(input: &str, selection: &str) -> Span {
     assert_eq!(input.len(), selection.len());
     let left_index = selection.find('~').unwrap() as u32;
-    let right_index = selection.rfind('~').map(|x| x as u32).unwrap_or(left_index);
+    let right_index = selection.rfind('~').map_or(left_index, |x| x as u32);
     Span::with_root_ctxt(BytePos(left_index), BytePos(right_index + 1))
 }