Handle early command output in prepare phase

4 files changed, 44 insertions, 4 deletions

diff --git a/src/bin/jvn.rs b/src/bin/jvn.rs
index b051c51..062eab8 100644
--- a/src/bin/jvn.rs
+++ b/src/bin/jvn.rs
@@ -279,6 +279,12 @@ fn handle_prepare_error(cmd_prepare_error: CmdPrepareError) {
         CmdPrepareError::NoSheetInUse => {
             eprintln!("{}", md(t!("prepare_error.no_sheet_in_use")));
         }
+        CmdPrepareError::EarlyOutput(_) => {
+            // Early output is not an error
+            // No additional handling needed,
+            //   this result has already been captured in `crate::systems::cmd::cmd_system.rs`
+            exit(0)
+        }
     }
 }
 
diff --git a/src/systems/cmd/cmd_system.rs b/src/systems/cmd/cmd_system.rs
index 7272c9e..43d5187 100644
--- a/src/systems/cmd/cmd_system.rs
+++ b/src/systems/cmd/cmd_system.rs
@@ -134,10 +134,18 @@ where
                 Self::collect(&parsed_args, &ctx)
             ) {
                 Ok((input, collect)) => (input, collect),
-                Err(e) => {
-                    error!("{}", t!("verbose.cmd_process_prepare_failed"));
-                    return Err(CmdProcessError::from(e));
-                }
+                Err(e) => match e {
+                    CmdPrepareError::EarlyOutput(any_output) => {
+                        // Early output is not an "error"
+                        // It's just that when the result can be determined early,
+                        // there's no need to wait until the execution phase to inform the user
+                        return Ok(any_output);
+                    }
+                    _ => {
+                        error!("{}", t!("verbose.cmd_process_prepare_failed"));
+                        return Err(CmdProcessError::from(e));
+                    }
+                },
             };
 
             info!("{}", t!("verbose.cmd_process_exec"));
diff --git a/src/systems/cmd/errors.rs b/src/systems/cmd/errors.rs
index abde5de..efa12a9 100644
--- a/src/systems/cmd/errors.rs
+++ b/src/systems/cmd/errors.rs
@@ -1,5 +1,7 @@
 use just_enough_vcs::lib::data::{member::MemberId, sheet::SheetName};
 
+use crate::systems::cmd::cmd_system::AnyOutput;
+
 #[derive(thiserror::Error, Debug)]
 pub enum CmdPrepareError {
     #[error("IO error: {0}")]
@@ -32,6 +34,9 @@ pub enum CmdPrepareError {
 
     #[error("No sheet in use")]
     NoSheetInUse,
+
+    #[error("Error occurred and returned early")]
+    EarlyOutput(AnyOutput),
 }
 
 impl CmdPrepareError {
diff --git a/src/systems/cmd/macros.rs b/src/systems/cmd/macros.rs
index 5763961..37b041c 100644
--- a/src/systems/cmd/macros.rs
+++ b/src/systems/cmd/macros.rs
@@ -163,6 +163,11 @@ macro_rules! command_template {
 }
 
 #[macro_export]
+/// `cmd_output!` 宏应在命令的 `exec` 函数中使用。
+/// 它负责将执行结果包装成能被指定渲染器匹配的格式。
+///
+/// 注意：该宏不仅是简化输出的工具，更是 JvcsCLI 代码生成流程的必要组成部分。
+/// 因此，所有命令的输出都必须通过此宏返回。
 macro_rules! cmd_output {
     ($t:ty => $v:expr) => {{
         let checked_value: $t = $v;
@@ -172,3 +177,19 @@ macro_rules! cmd_output {
         ))
     }};
 }
+
+#[macro_export]
+/// `early_cmd_output!` 宏应在命令的 `prepare` 或 `collect` 函数中使用。
+/// 它负责将执行结果包装成能返回到核心
+///
+/// 注意：该宏不仅是简化输出的工具，更是 JvcsCLI 代码生成流程的必要组成部分。
+/// 因此，所有命令的输出都必须通过此宏返回。
+macro_rules! early_cmd_output {
+    ($t:ty => $v:expr) => {{
+        let checked_value: $t = $v;
+        Err(crate::systems::cmd::errors::CmdPrepareError::EarlyOutput((
+            Box::new(checked_value) as Box<dyn std::any::Any + Send + 'static>,
+            std::any::TypeId::of::<$t>(),
+        )))
+    }};
+}