fix(test2)!: Dont require boxing in FnCase

Author: epage

crates/libtest2/examples/tidy.rs

@@ -1,3 +1,4 @@
+use libtest2::Case;
 use libtest2::FnCase;
 use libtest2::RunError;
 use libtest2::RunResult;
@@ -23,8 +24,8 @@ fn main() -> std::io::Result<()> {
 
 /// Creates one test for each `.rs` file in the current directory or
 /// sub-directories of the current directory.
-fn collect_tests() -> std::io::Result<Vec<FnCase>> {
-    fn visit_dir(path: &std::path::Path, tests: &mut Vec<FnCase>) -> std::io::Result<()> {
+fn collect_tests() -> std::io::Result<Vec<Box<dyn Case>>> {
+    fn visit_dir(path: &std::path::Path, tests: &mut Vec<Box<dyn Case>>) -> std::io::Result<()> {
         let current_dir = std::env::current_dir()?;
         for entry in std::fs::read_dir(path)? {
             let entry = entry?;
@@ -45,7 +46,7 @@ fn collect_tests() -> std::io::Result<Vec<FnCase>> {
                     .into_owned();
 
                     let test = FnCase::test(name, move |_| check_file(&path));
-                    tests.push(test);
+                    tests.push(Box::new(test));
                 }
             } else if file_type.is_dir() {
                 // Handle directories

crates/libtest2/src/case.rs

@@ -27,25 +27,27 @@ impl Case for DynCase {
     }
 }
 
-pub struct FnCase {
+pub struct FnCase<R> {
     name: String,
-    #[allow(clippy::type_complexity)]
-    runner: Box<dyn Fn(&TestContext) -> RunResult + Send + Sync>,
+    runner: R,
 }
 
-impl FnCase {
-    pub fn test(
-        name: impl Into<String>,
-        runner: impl Fn(&TestContext) -> RunResult + Send + Sync + 'static,
-    ) -> Self {
+impl<R> FnCase<R>
+where
+    R: Fn(&TestContext) -> RunResult + Send + Sync + 'static,
+{
+    pub fn test(name: impl Into<String>, runner: R) -> Self {
         Self {
             name: name.into(),
-            runner: Box::new(runner),
+            runner,
         }
     }
 }
 
-impl Case for FnCase {
+impl<R> Case for FnCase<R>
+where
+    R: Fn(&TestContext) -> RunResult + Send + Sync + 'static,
+{
     fn name(&self) -> &str {
         &self.name
     }

crates/libtest2/src/lib.rs

@@ -55,7 +55,6 @@ mod macros;
 pub mod _private {
     pub use distributed_list::push;
     pub use distributed_list::DistributedList;
-    pub use libtest2_harness::Case;
     pub use libtest2_harness::Source;
     pub use libtest2_harness::TestKind;
 
@@ -67,6 +66,7 @@ pub mod _private {
 
 pub use case::main;
 pub use case::FnCase;
+pub use libtest2_harness::Case;
 pub use libtest2_harness::IntoRunResult;
 pub use libtest2_harness::RunError;
 pub use libtest2_harness::RunResult;

crates/libtest2/src/macros.rs

@@ -33,7 +33,7 @@ macro_rules! _test_parse {
         #[allow(non_camel_case_types)]
         struct $name;
 
-        impl $crate::_private::Case for $name {
+        impl $crate::Case for $name {
             fn name(&self) -> &str {
                 $crate::_private::push!(crate::TESTS, _: $crate::_private::DynCase = $crate::_private::DynCase(&$name));