From 5498c24c33937105fd453e8e1e1243281fc7272b Mon Sep 17 00:00:00 2001
From: cyqsimon <28627918+cyqsimon@users.noreply.github.com>
Date: Thu, 2 Nov 2023 23:29:42 +0800
Subject: [PATCH] Rerun build script only when necessary

---
 build/application.rs | 8 ++++++++
 build/main.rs        | 4 ++++
 2 files changed, 12 insertions(+)

diff --git a/build/application.rs b/build/application.rs
index 4a6dc42f..459aa5b1 100644
--- a/build/application.rs
+++ b/build/application.rs
@@ -4,6 +4,14 @@ use crate::util::render_template;
 
 /// Generate manpage and shell completions for the bat application.
 pub fn gen_man_and_comp() -> anyhow::Result<()> {
+    println!("cargo:rerun-if-changed=assets/manual/");
+    println!("cargo:rerun-if-changed=assets/completions/");
+
+    println!("cargo:rerun-if-env-changed=PROJECT_NAME");
+    println!("cargo:rerun-if-env-changed=PROJECT_EXECUTABLE");
+    println!("cargo:rerun-if-env-changed=CARGO_PKG_VERSION");
+    println!("cargo:rerun-if-env-changed=BAT_ASSETS_GEN_DIR");
+
     // Read environment variables.
     let project_name = env::var("PROJECT_NAME").unwrap_or("bat".into());
     let executable_name = env::var("PROJECT_EXECUTABLE").unwrap_or(project_name.clone());
diff --git a/build/main.rs b/build/main.rs
index 5d33418b..416d90d5 100644
--- a/build/main.rs
+++ b/build/main.rs
@@ -3,6 +3,10 @@ mod application;
 mod util;
 
 fn main() -> anyhow::Result<()> {
+    // only watch manually-designated files
+    // see: https://doc.rust-lang.org/cargo/reference/build-scripts.html#rerun-if-changed
+    println!("cargo:rerun-if-changed=build/");
+
     #[cfg(feature = "application")]
     application::gen_man_and_comp()?;