Rollup merge of #117421 - Zalathar:error, r=oli-obk,Swatinem

coverage: Replace impossible `coverage::Error` with assertions

Historically, these errors existed so that the coverage debug code could dump additional information before reporting a compiler bug. That debug code was removed by #115962, so we can now simplify these methods by making them panic immediately when they detect a bug.

1 files changed, 2 insertions, 4 deletions

diff --git a/compiler/rustc_mir_transform/src/coverage/tests.rs b/compiler/rustc_mir_transform/src/coverage/tests.rs
index 795cbce963d..702fe5f563e 100644
--- a/compiler/rustc_mir_transform/src/coverage/tests.rs
+++ b/compiler/rustc_mir_transform/src/coverage/tests.rs
@@ -647,15 +647,13 @@ fn test_traverse_coverage_with_loops() {
 fn test_make_bcb_counters() {
     rustc_span::create_default_session_globals_then(|| {
         let mir_body = goto_switchint();
-        let mut basic_coverage_blocks = graph::CoverageGraph::from_mir(&mir_body);
+        let basic_coverage_blocks = graph::CoverageGraph::from_mir(&mir_body);
         // Historically this test would use `spans` internals to set up fake
         // coverage spans for BCBs 1 and 2. Now we skip that step and just tell
         // BCB counter construction that those BCBs have spans.
         let bcb_has_coverage_spans = |bcb: BasicCoverageBlock| (1..=2).contains(&bcb.as_usize());
         let mut coverage_counters = counters::CoverageCounters::new(&basic_coverage_blocks);
-        coverage_counters
-            .make_bcb_counters(&mut basic_coverage_blocks, bcb_has_coverage_spans)
-            .expect("should be Ok");
+        coverage_counters.make_bcb_counters(&basic_coverage_blocks, bcb_has_coverage_spans);
         assert_eq!(coverage_counters.num_expressions(), 0);
 
         let_bcb!(1);