rust-lang · tyilo · Mar 30, 2026 · Mar 30, 2026 · Mar 30, 2026 · weihanglo
diff --git a/src/cargo/ops/cargo_new.rs b/src/cargo/ops/cargo_new.rs
@@ -907,6 +907,7 @@ fn main() {
 "
         } else {
             b"\
+#[must_use]
 pub fn add(left: u64, right: u64) -> u64 {
     left + right
 }

diff --git a/tests/testsuite/cargo_init/auto_git/out/src/lib.rs b/tests/testsuite/cargo_init/auto_git/out/src/lib.rs
@@ -1,3 +1,4 @@
+#[must_use]
 pub fn add(left: u64, right: u64) -> u64 {
     left + right
 }

diff --git a/tests/testsuite/cargo_init/formats_source/out/src/lib.rs b/tests/testsuite/cargo_init/formats_source/out/src/lib.rs
@@ -1,3 +1,4 @@
+#[must_use]
 pub fn add(left: u64, right: u64) -> u64 {
   left + right
 }

diff --git a/tests/testsuite/cargo_init/fossil_autodetect/out/src/lib.rs b/tests/testsuite/cargo_init/fossil_autodetect/out/src/lib.rs
@@ -1,3 +1,4 @@
+#[must_use]
 pub fn add(left: u64, right: u64) -> u64 {
     left + right
 }

diff --git a/tests/testsuite/cargo_init/git_autodetect/out/src/lib.rs b/tests/testsuite/cargo_init/git_autodetect/out/src/lib.rs
@@ -1,3 +1,4 @@
+#[must_use]
 pub fn add(left: u64, right: u64) -> u64 {
     left + right
 }

diff --git a/tests/testsuite/cargo_init/git_ignore_exists_no_conflicting_entries/out/src/lib.rs b/tests/testsuite/cargo_init/git_ignore_exists_no_conflicting_entries/out/src/lib.rs
@@ -1,3 +1,4 @@
+#[must_use]
 pub fn add(left: u64, right: u64) -> u64 {
     left + right
 }

diff --git a/tests/testsuite/cargo_init/ignores_failure_to_format_source/out/src/lib.rs b/tests/testsuite/cargo_init/ignores_failure_to_format_source/out/src/lib.rs
@@ -1,3 +1,4 @@
+#[must_use]
 pub fn add(left: u64, right: u64) -> u64 {
     left + right
 }

diff --git a/tests/testsuite/cargo_init/mercurial_autodetect/out/src/lib.rs b/tests/testsuite/cargo_init/mercurial_autodetect/out/src/lib.rs
@@ -1,3 +1,4 @@
+#[must_use]
 pub fn add(left: u64, right: u64) -> u64 {
     left + right
 }

diff --git a/tests/testsuite/cargo_init/pijul_autodetect/out/src/lib.rs b/tests/testsuite/cargo_init/pijul_autodetect/out/src/lib.rs
@@ -1,3 +1,4 @@
+#[must_use]
 pub fn add(left: u64, right: u64) -> u64 {
     left + right
 }

diff --git a/tests/testsuite/cargo_init/simple_git/out/src/lib.rs b/tests/testsuite/cargo_init/simple_git/out/src/lib.rs
@@ -1,3 +1,4 @@
+#[must_use]
 pub fn add(left: u64, right: u64) -> u64 {
     left + right
 }

diff --git a/tests/testsuite/cargo_init/simple_git_ignore_exists/out/src/lib.rs b/tests/testsuite/cargo_init/simple_git_ignore_exists/out/src/lib.rs
@@ -1,3 +1,4 @@
+#[must_use]
 pub fn add(left: u64, right: u64) -> u64 {
     left + right
 }

diff --git a/tests/testsuite/cargo_init/simple_hg/out/src/lib.rs b/tests/testsuite/cargo_init/simple_hg/out/src/lib.rs
@@ -1,3 +1,4 @@
+#[must_use]
 pub fn add(left: u64, right: u64) -> u64 {
     left + right
 }

diff --git a/tests/testsuite/cargo_init/simple_hg_ignore_exists/out/src/lib.rs b/tests/testsuite/cargo_init/simple_hg_ignore_exists/out/src/lib.rs
@@ -1,3 +1,4 @@
+#[must_use]
 pub fn add(left: u64, right: u64) -> u64 {
     left + right
 }

diff --git a/tests/testsuite/cargo_init/simple_lib/out/src/lib.rs b/tests/testsuite/cargo_init/simple_lib/out/src/lib.rs
@@ -1,3 +1,4 @@
+#[must_use]
 pub fn add(left: u64, right: u64) -> u64 {
     left + right
 }

diff --git a/tests/testsuite/cargo_new/add_members_to_non_workspace/out/bar/src/lib.rs b/tests/testsuite/cargo_new/add_members_to_non_workspace/out/bar/src/lib.rs
@@ -1,3 +1,4 @@
+#[must_use]
 pub fn add(left: u64, right: u64) -> u64 {
     left + right
 }

diff --git a/tests/testsuite/cargo_new/add_members_to_workspace_without_members/out/bar/src/lib.rs b/tests/testsuite/cargo_new/add_members_to_workspace_without_members/out/bar/src/lib.rs
@@ -1,3 +1,4 @@
+#[must_use]
 pub fn add(left: u64, right: u64) -> u64 {
     left + right
 }

diff --git a/tests/testsuite/cargo_new/ignore_current_dir_workspace/out/out-of-workspace/src/lib.rs b/tests/testsuite/cargo_new/ignore_current_dir_workspace/out/out-of-workspace/src/lib.rs
@@ -1,3 +1,4 @@
+#[must_use]
 pub fn add(left: u64, right: u64) -> u64 {
     left + right
 }

diff --git a/tests/testsuite/new.rs b/tests/testsuite/new.rs
@@ -46,7 +46,8 @@ fn simple_lib() {
     let contents = fs::read_to_string(&lib).unwrap();
     assert_eq!(
         contents,
-        r#"pub fn add(left: u64, right: u64) -> u64 {
+        r#"#[must_use]
+pub fn add(left: u64, right: u64) -> u64 {
     left + right
 }