Reuse Android builds and discard staging

iris/cargo-iris/src/package.rs

@@ -173,7 +173,9 @@ fn build(options: &Options) -> Result<Built, String> {
         .join(variant)
         .join(&options.abi);
     recreate(&output)?;
-    let native = output.join("native");
+    let staging = output.join("staging");
+    let staging_cleanup = RemoveDirOnDrop(&staging);
+    let native = staging.join("native");
     let (build_manifest, library_name) = if options.example.is_some() {
         let wrapper = metadata
             .target_directory
@@ -213,9 +215,9 @@ fn build(options: &Options) -> Result<Built, String> {
     if !library.is_file() {
         return Err(format!("cargo-ndk did not produce {}", library.display()));
     }
-    let classes = output.join("classes");
+    let classes = staging.join("classes");
     fs::create_dir_all(&classes).map_err(io_error("create Java output", &classes))?;
-    let sources = materialize_host(&output, &library_name)?;
+    let sources = materialize_host(&staging, &library_name)?;
     let java_files = files_with_extension(&sources, "java")?;
     let mut javac = Command::new("javac");
     javac
@@ -230,7 +232,7 @@ fn build(options: &Options) -> Result<Built, String> {
         "install a JDK containing javac",
     )?;
 
-    let dex = output.join("dex");
+    let dex = staging.join("dex");
     fs::create_dir_all(&dex).map_err(io_error("create DEX output", &dex))?;
     let class_files = files_with_extension(&classes, "class")?;
     let mut d8 = Command::new(&sdk.d8);
@@ -250,13 +252,13 @@ fn build(options: &Options) -> Result<Built, String> {
         "install Android SDK Build Tools",
     )?;
 
-    let manifest = output.join("AndroidManifest.xml");
+    let manifest = staging.join("AndroidManifest.xml");
     fs::write(
         &manifest,
         manifest_xml(&application_id, &label, &library_name, sdk.api),
     )
     .map_err(io_error("write Android manifest", &manifest))?;
-    let unsigned = output.join("unsigned.apk");
+    let unsigned = staging.join("unsigned.apk");
     let mut aapt = Command::new(&sdk.aapt2);
     aapt.arg("link")
         .arg("-o")
@@ -278,14 +280,14 @@ fn build(options: &Options) -> Result<Built, String> {
     )?;
     append_payload(
         &unsigned,
-        &output,
+        &staging,
         &dex.join("classes.dex"),
         &library,
         &options.abi,
         &library_name,
     )?;
 
-    let aligned = output.join("aligned.apk");
+    let aligned = staging.join("aligned.apk");
     let mut zipalign = Command::new(&sdk.zipalign);
     zipalign
         .args(["-P", "16", "-f", "4"])
@@ -299,6 +301,8 @@ fn build(options: &Options) -> Result<Built, String> {
     let apk = output.join(format!("{artifact}-{variant}.apk"));
     sign(&sdk, options, &aligned, &apk)?;
     verify(&sdk, &apk)?;
+    fs::remove_dir_all(&staging).map_err(io_error("remove APK staging directory", &staging))?;
+    std::mem::forget(staging_cleanup);
     Ok(Built {
         apk,
         application_id,
@@ -405,23 +409,33 @@ fn materialize_example_wrapper(
     let manifest = format!(
         "[package]\nname = {name:?}\nversion = \"0.0.0\"\nedition = \"2024\"\n\n\
          [lib]\nname = {library_name:?}\ncrate-type = [\"cdylib\", \"rlib\"]\n\n\
-         [dependencies]\niris = {{ path = {iris_root:?} }}\n\n[workspace]\n",
+         [dependencies]\niris = {{ path = {iris_root:?} }}\n\n[workspace]\n\n\
+         [profile.dev]\ndebug = \"line-tables-only\"\n",
         name = format!("iris-android-{}-{}", package.name, example.name),
         iris_root = iris_root.as_str(),
     );
     let manifest_path = wrapper.join("Cargo.toml");
-    fs::write(&manifest_path, manifest)
+    write_if_changed(&manifest_path, &manifest)?;
-        .map_err(io_error("write Android example manifest", &manifest_path))?;
     let source = format!(
         "#[path = {:?}]\nmod example;\n",
         android_source.to_string_lossy()
     );
     let source_path = source_dir.join("lib.rs");
-    fs::write(&source_path, source)
+    write_if_changed(&source_path, &source)?;
-        .map_err(io_error("write Android example wrapper", &source_path))?;
     Ok((manifest_path, library_name))
 }
 
+fn write_if_changed(path: &Path, contents: &str) -> Result<bool, String> {
+    match fs::read(path) {
+        Ok(existing) if existing == contents.as_bytes() => return Ok(false),
+        Ok(_) => {}
+        Err(error) if error.kind() == std::io::ErrorKind::NotFound => {}
+        Err(error) => return Err(format!("cannot read {}: {error}", path.display())),
+    }
+    fs::write(path, contents).map_err(io_error("write generated file", path))?;
+    Ok(true)
+}
+
 fn metadata_string(package: &Package, key: &str) -> Option<String> {
     package
         .metadata
@@ -481,6 +495,16 @@ struct Sdk {
     adb: PathBuf,
 }
 
+/// Failed builds have no reusable staging output either; the next invocation
+/// starts from scratch, so do not make a failure consume disk indefinitely.
+struct RemoveDirOnDrop<'a>(&'a Path);
+
+impl Drop for RemoveDirOnDrop<'_> {
+    fn drop(&mut self) {
+        let _ = fs::remove_dir_all(self.0);
+    }
+}
+
 impl Sdk {
     fn find() -> Result<Self, String> {
         let root = env::var_os("ANDROID_HOME")
@@ -700,9 +724,13 @@ fn sign(sdk: &Sdk, options: &Options, input: &Path, output: &Path) -> Result<(),
         )
     };
     let mut command = Command::new(&sdk.apksigner);
+    // `install_and_run` uses `--no-streaming`, so it cannot consume the separate
+    // v4 `.idsig` file and retaining that sidecar beside the APK serves no caller.
     command
         .arg("sign")
         .args([
+            "--v4-signing-enabled",
+            "false",
             "--ks-pass",
             "env:IRIS_APK_STORE_PASSWORD",
             "--key-pass",
@@ -799,9 +827,9 @@ fn install_and_run(built: &Built, device: &str) -> Result<(), String> {
 
 fn recreate(path: &Path) -> Result<(), String> {
     if path.exists() {
-        fs::remove_dir_all(path).map_err(io_error("clear prior APK staging directory", path))?;
+        fs::remove_dir_all(path).map_err(io_error("clear prior APK output directory", path))?;
     }
-    fs::create_dir_all(path).map_err(io_error("create APK staging directory", path))
+    fs::create_dir_all(path).map_err(io_error("create APK output directory", path))
 }
 
 fn run_command(command: &mut Command, thing: &str, fix: &str) -> Result<(), String> {
@@ -842,4 +870,33 @@ mod tests {
         assert!(manifest.contains("A &amp; &lt;demo&gt;"));
         assert!(manifest.contains("android:minSdkVersion=\"29\""));
     }
+
+    #[test]
+    fn an_unchanged_generated_file_is_not_rewritten() {
+        let root = env::temp_dir().join(format!("cargo-iris-write-test-{}", std::process::id()));
+        let path = root.join("generated.rs");
+        let _ = fs::remove_dir_all(&root);
+        fs::create_dir_all(&root).unwrap();
+
+        assert!(write_if_changed(&path, "first").unwrap());
+        assert!(!write_if_changed(&path, "first").unwrap());
+        assert!(write_if_changed(&path, "second").unwrap());
+        assert_eq!(fs::read_to_string(&path).unwrap(), "second");
+
+        fs::remove_dir_all(root).unwrap();
+    }
+
+    #[test]
+    fn failed_build_staging_is_removed_when_its_scope_ends() {
+        let root = env::temp_dir().join(format!("cargo-iris-staging-test-{}", std::process::id()));
+        let _ = fs::remove_dir_all(&root);
+        fs::create_dir_all(&root).unwrap();
+        fs::write(root.join("intermediate"), "not reusable").unwrap();
+
+        {
+            let _cleanup = RemoveDirOnDrop(&root);
+        }
+
+        assert!(!root.exists());
+    }
 }

iris/cargo-iris/tests/fixture/.gitignore

@@ -1,2 +0,0 @@
-/Cargo.lock
-/target/

iris/cargo-iris/tests/fixture/Cargo.toml

@@ -1,12 +0,0 @@
-[package]
-name = "iris-apk-fixture"
-version = "0.1.0"
-edition = "2024"
-
-[lib]
-crate-type = ["cdylib", "rlib"]
-
-[dependencies]
-iris = { path = "../../.." }
-
-[workspace]

iris/cargo-iris/tests/fixture/src/lib.rs

@@ -1,97 +0,0 @@
-use iris::prelude::*;
-use std::sync::Arc;
-
-#[derive(AndroidUiState)]
-pub struct State {
-    ui_state: AndroidUiState,
-}
-
-impl AndroidAppState for State {
-    type Resources = Resources;
-}
-
-#[iris::android_init]
-fn create(mut ui_state: AndroidUiState, rsc: &mut Resources) -> State {
-    rsc.launches += 1;
-    rect(PaintId::RED)
-        .label("Iris APK fixture")
-        .set_root(rsc, &mut ui_state);
-    State { ui_state }
-}
-
-pub struct Resources {
-    ui: Ui,
-    events: EventManager<Self>,
-    tasks: Tasks<Self>,
-    widget_state: WidgetState,
-    launches: u32,
-}
-
-impl AndroidResources<State> for Resources {
-    fn new(wake: Arc<dyn WakeTaskQueue>) -> (Self, TaskMsgReceiver<Self>) {
-        let (tasks, receiver) = Tasks::init(wake);
-        (
-            Self {
-                ui: Ui::default(),
-                events: EventManager::default(),
-                tasks,
-                widget_state: WidgetState::default(),
-                launches: 0,
-            },
-            receiver,
-        )
-    }
-}
-
-impl UiRsc for Resources {
-    fn ui(&self) -> &Ui {
-        &self.ui
-    }
-
-    fn ui_mut(&mut self) -> &mut Ui {
-        &mut self.ui
-    }
-
-    fn on_draw(&mut self, active: &ActiveData) {
-        self.events.draw(active);
-    }
-
-    fn on_undraw(&mut self, active: &ActiveData) {
-        self.events.undraw(active);
-    }
-
-    fn on_remove(&mut self, id: WidgetId) {
-        self.events.remove(id);
-        self.widget_state.remove(id);
-    }
-}
-
-impl HasState for Resources {
-    type State = State;
-}
-
-impl HasEvents for Resources {
-    fn events(&self) -> &EventManager<Self> {
-        &self.events
-    }
-
-    fn events_mut(&mut self) -> &mut EventManager<Self> {
-        &mut self.events
-    }
-}
-
-impl HasTasks for Resources {
-    fn tasks_mut(&mut self) -> &mut Tasks<Self> {
-        &mut self.tasks
-    }
-}
-
-impl HasWidgetState for Resources {
-    fn widget_state(&self) -> &WidgetState {
-        &self.widget_state
-    }
-
-    fn widget_state_mut(&mut self) -> &mut WidgetState {
-        &mut self.widget_state
-    }
-}

iris/readme.md

@@ -101,9 +101,9 @@ IRIS_KEYSTORE_PASSWORD=... IRIS_KEY_PASSWORD=... \
   cargo iris apk --release --keystore /secure/upload.jks --key-alias upload
 ```
 
-APK staging and output live under
+The verified APK lives under
-`target/iris-android/<package>[-<example>]/<debug|release>/<abi>/`; the
+`target/iris-android/<package>[-<example>]/<debug|release>/<abi>/`; packaging
-command's final line is the verified APK's absolute path.
+intermediates are removed before the command prints its absolute path.
 
 Goals, in general order:
 1. does what I want it to (text, images, video, animations)