fix: build scripts fall back gracefully when icon.ico is absent

Author: Hexeption

crates/fastpack-gui/build.rs

@@ -1,31 +1,37 @@
 use std::{env, fs, io::BufReader, path::PathBuf};
 
 fn main() {
-    println!("cargo:rerun-if-changed=../../assets/icon.ico");
-
+    let manifest_dir = PathBuf::from(env::var("CARGO_MANIFEST_DIR").unwrap());
+    let ico_path = manifest_dir.join("../../assets/icon.ico");
     let out = PathBuf::from(env::var("OUT_DIR").unwrap());
-    let ico_path = "../../assets/icon.ico";
-
-    let file = BufReader::new(fs::File::open(ico_path).expect("assets/icon.ico not found"));
-    let dir = ico::IconDir::read(file).expect("parse icon.ico");
 
-    let entry = dir
-        .entries()
-        .iter()
-        .max_by_key(|e| e.width())
-        .expect("icon.ico is empty");
-
-    let image = entry.decode().expect("decode icon entry");
-    let (w, h) = (image.width(), image.height());
-    let rgba = image.rgba_data().to_vec();
+    println!("cargo:rerun-if-changed=../../assets/icon.ico");
 
-    fs::write(out.join("icon.rgba"), &rgba).expect("write icon.rgba");
-    fs::write(
-        out.join("icon_meta.rs"),
-        format!(
-            "const ICON_WIDTH: u32 = {};\nconst ICON_HEIGHT: u32 = {};\n",
-            w, h
-        ),
-    )
-    .expect("write icon_meta.rs");
+    if ico_path.exists() {
+        let file = BufReader::new(fs::File::open(&ico_path).expect("open icon.ico"));
+        let dir = ico::IconDir::read(file).expect("parse icon.ico");
+        let entry = dir
+            .entries()
+            .iter()
+            .max_by_key(|e| e.width())
+            .expect("icon.ico is empty");
+        let image = entry.decode().expect("decode icon entry");
+        let (w, h) = (image.width(), image.height());
+        let rgba = image.rgba_data().to_vec();
+        fs::write(out.join("icon.rgba"), &rgba).expect("write icon.rgba");
+        fs::write(
+            out.join("icon_meta.rs"),
+            format!("const ICON_WIDTH: u32 = {w};\nconst ICON_HEIGHT: u32 = {h};\n"),
+        )
+        .expect("write icon_meta.rs");
+    } else {
+        // No icon available (e.g. during `cargo publish` verification).
+        // Write a 1×1 transparent placeholder so the crate still compiles.
+        fs::write(out.join("icon.rgba"), [0u8, 0, 0, 0]).expect("write icon.rgba");
+        fs::write(
+            out.join("icon_meta.rs"),
+            "const ICON_WIDTH: u32 = 1;\nconst ICON_HEIGHT: u32 = 1;\n",
+        )
+        .expect("write icon_meta.rs");
+    }
 }

crates/fastpack/build.rs

@@ -1,13 +1,19 @@
 fn main() {
     println!("cargo:rerun-if-changed=../../assets/icon.ico");
+
     #[cfg(target_os = "windows")]
-    embed_icon_resource();
+    embed_if_present();
 }
 
 #[cfg(target_os = "windows")]
-fn embed_icon_resource() {
-    winresource::WindowsResource::new()
-        .set_icon("../../assets/icon.ico")
-        .compile()
-        .expect("winresource compile failed");
+fn embed_if_present() {
+    use std::{env, path::PathBuf};
+    let manifest_dir = PathBuf::from(env::var("CARGO_MANIFEST_DIR").unwrap());
+    let ico_path = manifest_dir.join("../../assets/icon.ico");
+    if ico_path.exists() {
+        winresource::WindowsResource::new()
+            .set_icon(ico_path.to_str().expect("icon path is not valid UTF-8"))
+            .compile()
+            .expect("winresource compile failed");
+    }
 }