fix bug #15703

Author: hkBst

src/cargo/util/toml/targets.rs

@@ -972,15 +972,14 @@ fn target_path_not_found_error_message(
             }
             _ => unreachable!("invalid target kind: {}", kind),
         }
-        target_path.push(name);
 
         let target_path_file = {
             let mut path = target_path.clone();
-            path.set_extension("rs");
+            path.push(format!("{name}.rs"));
             path
         };
         let target_path_subdir = {
-            target_path.push("main.rs");
+            target_path.extend([name, "main.rs"]);
             target_path
         };
         return [target_path_file, target_path_subdir];

tests/testsuite/bad_config.rs

@@ -3072,7 +3072,7 @@ fn bad_bin_name() {
 [ERROR] failed to parse manifest at `[ROOT]/foo/Cargo.toml`
 
 Caused by:
-  can't find `bin.rs` bin at `src/bin/bin.rs` or `src/bin/bin.rs/main.rs`. Please specify bin.path if you want to use a non-default path.
+  can't find `bin.rs` bin at `src/bin/bin.rs.rs` or `src/bin/bin.rs/main.rs`. Please specify bin.path if you want to use a non-default path.
 
 "#]])
         .run();
@@ -3087,7 +3087,7 @@ fn bad_example_name() {
 [ERROR] failed to parse manifest at `[ROOT]/foo/Cargo.toml`
 
 Caused by:
-  can't find `example.rs` example at `examples/example.rs` or `examples/example.rs/main.rs`. Please specify example.path if you want to use a non-default path.
+  can't find `example.rs` example at `examples/example.rs.rs` or `examples/example.rs/main.rs`. Please specify example.path if you want to use a non-default path.
 
 "#]])
         .run();
@@ -3102,7 +3102,7 @@ fn bad_test_name() {
 [ERROR] failed to parse manifest at `[ROOT]/foo/Cargo.toml`
 
 Caused by:
-  can't find `test.rs` test at `tests/test.rs` or `tests/test.rs/main.rs`. Please specify test.path if you want to use a non-default path.
+  can't find `test.rs` test at `tests/test.rs.rs` or `tests/test.rs/main.rs`. Please specify test.path if you want to use a non-default path.
 
 "#]])
         .run();
@@ -3117,7 +3117,7 @@ fn bad_bench_name() {
 [ERROR] failed to parse manifest at `[ROOT]/foo/Cargo.toml`
 
 Caused by:
-  can't find `bench.rs` bench at `benches/bench.rs` or `benches/bench.rs/main.rs`. Please specify bench.path if you want to use a non-default path.
+  can't find `bench.rs` bench at `benches/bench.rs.rs` or `benches/bench.rs/main.rs`. Please specify bench.path if you want to use a non-default path.
 
 "#]])
         .run();