chore!: simplify ExitCodeSetup to non-generic unit struct

8 files changed, 67 insertions, 32 deletions

diff --git a/CHANGELOG.md b/CHANGELOG.md
index a3090b4..e216f6b 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -477,6 +477,25 @@ None
 
     _No behavioral changes — the setup still registers the same four directory resources (`ResCurrentDir`, `ResCurrentExe`, `ResHomeDir`, `ResTempDir`) in the program's resource store. The type simplification is purely ergonomic.
 
+10. **[`setups:exit_code`]** **[BREAKING]** Simplified the `ExitCodeSetup` type — it is no longer generic over the program collect type `C` and no longer requires `ExitCodeSetup::<C>::default()` to construct.
+
+    ### What changed
+
+    Previously, `ExitCodeSetup` was a generic struct `ExitCodeSetup<C>` (carrying `PhantomData<C>`) that had to be constructed via `ExitCodeSetup::<C>::default()` before calling `Program::with_setup`. Now the struct is unit-like (`pub struct ExitCodeSetup;`), so it can be constructed directly as a value with no `::default()` call and no generic parameter.
+
+    Additionally, the `setup` method's `program` parameter was retyped from `crate::Program<C>` to `mingling_core::Program<C>` for cleanliness.
+
+    ### Removed / changed API
+    - **`ExitCodeSetup<C>`** → **`ExitCodeSetup`** — The struct no longer has a generic parameter (previously `ExitCodeSetup<C>` with `PhantomData<C>`).
+    - **`impl<C> Default for ExitCodeSetup<C>`** — Removed. The unit struct uses the derived/implicit `Default`, and more importantly construction is now just the plain value `ExitCodeSetup`, not `ExitCodeSetup::<C>::default()`.
+    - **`impl<C> ProgramSetup<C> for ExitCodeSetup<C>`** → **`impl<C> ProgramSetup<C> for ExitCodeSetup`** — The `ProgramSetup` impl is now on the unit type.
+
+    ### Migration guide
+    - Replace `program.with_setup(ExitCodeSetup::<ThisProgram>::default())` (or `ExitCodeSetup::default()`) with `program.with_setup(ExitCodeSetup)`.
+    - Any type annotations referencing `ExitCodeSetup<C>` must drop the generic argument.
+
+    _No behavioral changes — the setup still registers the same `ResExitCode` resource (initialised to `0`) and installs the same program-finish hook that overrides the program's exit code when the resource holds a non-zero value. The type simplification is purely ergonomic._
+
 ---
 
 ## Contents
diff --git a/docs/_zh_CN/pages/12-exit-code.md b/docs/_zh_CN/pages/12-exit-code.md
index 9270b84..1f9e05c 100644
--- a/docs/_zh_CN/pages/12-exit-code.md
+++ b/docs/_zh_CN/pages/12-exit-code.md
@@ -12,7 +12,7 @@
 @@@use mingling::setup::ExitCodeSetup;
 fn main() {
     let mut program = ThisProgram::new();
-    program.with_setup(ExitCodeSetup::default());
+    program.with_setup(ExitCodeSetup);
 @@@ program.exec_and_exit();
 }
 ```
@@ -55,7 +55,7 @@ fn handle_check(_args: EntryCheck, ec: &mut ResExitCode) {
 @@@use mingling::setup::ExitCodeSetup;
 fn main() {
     let mut program = ThisProgram::new();
-    program.with_setup(ExitCodeSetup::default());
+    program.with_setup(ExitCodeSetup);
  
     // 获取退出码自行处理
     let exit_code = program.exec();
diff --git a/docs/pages/12-exit-code.md b/docs/pages/12-exit-code.md
index 8fa320c..e9ad9de 100644
--- a/docs/pages/12-exit-code.md
+++ b/docs/pages/12-exit-code.md
@@ -12,7 +12,7 @@ Providing the shell with a correct exit code when a program terminates is a basi
 @@@use mingling::setup::ExitCodeSetup;
 fn main() {
     let mut program = ThisProgram::new();
-    program.with_setup(ExitCodeSetup::default());
+    program.with_setup(ExitCodeSetup);
 @@@ program.exec_and_exit();
 }
 ```
@@ -55,7 +55,7 @@ fn handle_check(_args: EntryCheck, ec: &mut ResExitCode) {
 @@@use mingling::setup::ExitCodeSetup;
 fn main() {
     let mut program = ThisProgram::new();
-    program.with_setup(ExitCodeSetup::default());
+    program.with_setup(ExitCodeSetup);
  
     // Get exit code and handle it yourself
     let exit_code = program.exec();
diff --git a/examples/example-exitcode/src/main.rs b/examples/example-exitcode/src/main.rs
index c7f731d..f0db05b 100644
--- a/examples/example-exitcode/src/main.rs
+++ b/examples/example-exitcode/src/main.rs
@@ -28,7 +28,7 @@ fn main() {
 
     // --------- IMPORTANT ---------
     // Register `ExitCodeSetup` for the program to enable exit codes
-    program.with_setup(ExitCodeSetup::default());
+    program.with_setup(ExitCodeSetup);
     // --------- IMPORTANT ---------
 
     program.exec_and_exit();
diff --git a/examples/full-todolist/src/main.rs b/examples/full-todolist/src/main.rs
index 9c7bfe8..cac2e13 100644
--- a/examples/full-todolist/src/main.rs
+++ b/examples/full-todolist/src/main.rs
@@ -60,7 +60,7 @@ fn main() {
     let mut program = ThisProgram::new();
 
     // Setups
-    program.with_setup(ExitCodeSetup::default());
+    program.with_setup(ExitCodeSetup);
     program.with_setup(StructuralRendererSetup);
     program.with_setup(HelpFlagSetup::new(&arg![help: Flag, 'h']));
 
diff --git a/mingling/src/example_docs.rs b/mingling/src/example_docs.rs
index c9955b5..055615d 100644
--- a/mingling/src/example_docs.rs
+++ b/mingling/src/example_docs.rs
@@ -1318,7 +1318,7 @@ pub mod example_error_handling {}
 ///
 ///     // --------- IMPORTANT ---------
 ///     // Register `ExitCodeSetup` for the program to enable exit codes
-///     program.with_setup(ExitCodeSetup::default());
+///     program.with_setup(ExitCodeSetup);
 ///     // --------- IMPORTANT ---------
 ///
 ///     program.exec_and_exit();
diff --git a/mingling/src/setups/exit_code.rs b/mingling/src/setups/exit_code.rs
index e31e511..0558892 100644
--- a/mingling/src/setups/exit_code.rs
+++ b/mingling/src/setups/exit_code.rs
@@ -1,8 +1,5 @@
-// Doc Not Optimize
-use std::marker::PhantomData;
-
 use mingling_core::{
-    ProgramCollect,
+    Program, ProgramCollect,
     hook::{ProgramControlUnit, ProgramControls, ProgramHook},
     setup::ProgramSetup,
     this,
@@ -10,30 +7,49 @@ use mingling_core::{
 
 use crate::res::ResExitCode;
 
-/// Provides the ability to control the program's exit code, which is returned when the program ends.
+/// `ExitCodeSetup` — Setup for controlling the program's exit code
 ///
-/// - Use `mingling::update_exit_code` to update the exit code.
-/// - Use `mingling::current_exit_code` to query the current exit code.
-pub struct ExitCodeSetup<C> {
-    _collect: PhantomData<C>,
-}
-
-impl<C> Default for ExitCodeSetup<C>
-where
-    C: ProgramCollect<Enum = C> + 'static,
-{
-    fn default() -> Self {
-        Self {
-            _collect: PhantomData,
-        }
-    }
-}
+/// This Setup registers an [`ResExitCode`] resource that tracks the desired exit
+/// code for the program. When the program finishes, a hook reads this resource
+/// and overrides the program's exit code if it has been modified from its
+/// default value of `0`.
+///
+/// # Usage
+///
+/// This Setup can be registered using the
+/// [`Program`](https://docs.rs/mingling/latest/mingling/struct.Program.html)
+/// `with_setup` method, for example:
+///
+/// ```rust
+/// # use mingling::MockProgramCollect as ThisProgram;
+/// use mingling::Program;
+/// use mingling::setup::ExitCodeSetup;
+///
+/// let mut program = Program::<ThisProgram>::new();
+/// program.with_setup(ExitCodeSetup);
+/// ```
+///
+/// # Behavior
+///
+/// - Registers an [`ResExitCode`] resource initialised to `0`.
+/// - Installs a program-finish hook that:
+///   - Reads the current [`ResExitCode`] value.
+///   - Overrides the program's exit code with that value if it is non-zero.
+///   - Leaves the exit code untouched if the resource still holds its default
+///     value of `0`.
+///
+/// # Notes
+///
+/// - Use [`update_exit_code`](crate::update_exit_code) to set a custom exit code
+///   during program execution.
+/// - Use [`current_exit_code`](crate::current_exit_code) to query the current value.
+pub struct ExitCodeSetup;
 
-impl<C> ProgramSetup<C> for ExitCodeSetup<C>
+impl<C> ProgramSetup<C> for ExitCodeSetup
 where
     C: ProgramCollect<Enum = C> + 'static,
 {
-    fn setup(self, program: &mut crate::Program<C>) {
+    fn setup(self, program: &mut Program<C>) {
         // Insert resource
         program.with_resource(ResExitCode { exit_code: 0 });
 
diff --git a/mingling_cli/src/bin/cli.rs b/mingling_cli/src/bin/cli.rs
index f641749..d0c9e8b 100644
--- a/mingling_cli/src/bin/cli.rs
+++ b/mingling_cli/src/bin/cli.rs
@@ -10,8 +10,8 @@ async fn main() {
 
     // Setups
     program.with_setup(HelpFlagSetup::default());
-    program.with_setup(ExitCodeSetup::default());
-    program.with_setup(DirectoryEnvironmentSetup::default());
+    program.with_setup(ExitCodeSetup);
+    program.with_setup(DirectoryEnvironmentSetup);
 
     program.with_setup(MinglingMetadataSetup);
     program.with_setup(MlingConfigSetup);