feat(ir): add typed builder for DownloadPackage@1

src/compile/agentic_pipeline.rs

@@ -65,6 +65,7 @@ use super::ir::step::{
     BashStep, CheckoutRepo, CheckoutStep, DownloadStep, PublishStep, Step, SubmodulesOpt, TaskStep,
 };
 use super::ir::tasks::docker_installer::DockerInstaller;
+use super::ir::tasks::download_package::DownloadPackage;
 use super::ir::{
     CiTrigger, Parameter, ParameterDefault, ParameterKind, PipelineResource, PipelineVar,
     PrTrigger, RepositoryResource, Resources, Schedule, Triggers,
@@ -1222,12 +1223,9 @@ pub(crate) fn download_package_step(
     version: &str,
     download_path: &str,
 ) -> TaskStep {
-    TaskStep::new("DownloadPackage@1", display)
-        .with_input("packageType", "nuget")
-        .with_input("feed", feed)
-        .with_input("definition", package)
-        .with_input("version", version)
-        .with_input("downloadPath", download_path)
+    DownloadPackage::nuget(feed, package, version, download_path)
+        .with_display_name(display)
+        .into_step()
 }
 
 /// Bash body that locates a payload file inside a `DownloadPackage@1` staging

src/compile/ir/tasks/download_package.rs

@@ -0,0 +1,205 @@
+//! Typed builder for `DownloadPackage@1`.
+
+use super::common::{bool_input, push_opt};
+use crate::compile::ir::step::TaskStep;
+
+/// Package ecosystem for [`DownloadPackage`] (`packageType` input).
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum PackageType {
+    NuGet,
+    Npm,
+    PyPi,
+    Maven,
+    UPack,
+    Cargo,
+}
+
+impl PackageType {
+    /// The exact token the ADO task expects.
+    pub fn as_ado_str(self) -> &'static str {
+        match self {
+            PackageType::NuGet => "nuget",
+            PackageType::Npm => "npm",
+            PackageType::PyPi => "pypi",
+            PackageType::Maven => "maven",
+            PackageType::UPack => "upack",
+            PackageType::Cargo => "cargo",
+        }
+    }
+}
+
+/// Builder for a [`TaskStep`] invoking `DownloadPackage@1`.
+///
+/// Downloads a package from an Azure Artifacts feed into `download_path`.
+/// The required inputs are `package_type`, `feed`, `definition` (package
+/// name), `version`, and `download_path`; optional inputs are applied through
+/// typed setters and only emitted when set.
+///
+/// Use [`DownloadPackage::nuget`] as a convenience constructor when downloading
+/// NuGet packages (the most common case in ado-aw supply-chain steps).
+///
+/// ADO task reference:
+/// <https://learn.microsoft.com/en-us/azure/devops/pipelines/tasks/reference/download-package-v1-task>
+#[derive(Debug, Clone)]
+pub struct DownloadPackage {
+    package_type: PackageType,
+    feed: String,
+    /// The package name (`definition` input).
+    definition: String,
+    version: String,
+    download_path: String,
+    view: Option<String>,
+    files: Option<String>,
+    extract: Option<bool>,
+    display_name: Option<String>,
+}
+
+impl DownloadPackage {
+    /// Required inputs: `packageType`, `feed`, package `definition`, `version`,
+    /// and `downloadPath`.
+    pub fn new(
+        package_type: PackageType,
+        feed: impl Into<String>,
+        definition: impl Into<String>,
+        version: impl Into<String>,
+        download_path: impl Into<String>,
+    ) -> Self {
+        Self {
+            package_type,
+            feed: feed.into(),
+            definition: definition.into(),
+            version: version.into(),
+            download_path: download_path.into(),
+            view: None,
+            files: None,
+            extract: None,
+            display_name: None,
+        }
+    }
+
+    /// Convenience constructor for NuGet packages.
+    pub fn nuget(
+        feed: impl Into<String>,
+        definition: impl Into<String>,
+        version: impl Into<String>,
+        download_path: impl Into<String>,
+    ) -> Self {
+        Self::new(PackageType::NuGet, feed, definition, version, download_path)
+    }
+
+    /// `view` — view within the feed to resolve the package from (e.g.
+    /// `"Release"`, `"Prerelease"`). Omit to resolve from the feed directly.
+    pub fn view(mut self, value: impl Into<String>) -> Self {
+        self.view = Some(value.into());
+        self
+    }
+
+    /// `files` — glob patterns selecting files to download from the package
+    /// (default: `"**"` — all files).
+    pub fn files(mut self, value: impl Into<String>) -> Self {
+        self.files = Some(value.into());
+        self
+    }
+
+    /// `extract` — whether to extract the package contents after download
+    /// (default: `true`).
+    pub fn extract(mut self, value: bool) -> Self {
+        self.extract = Some(value);
+        self
+    }
+
+    /// Override the default `displayName` (`"Download Package"`).
+    pub fn with_display_name(mut self, value: impl Into<String>) -> Self {
+        self.display_name = Some(value.into());
+        self
+    }
+
+    /// Lower into a [`TaskStep`].
+    pub fn into_step(self) -> TaskStep {
+        let mut t = TaskStep::new(
+            "DownloadPackage@1",
+            self.display_name.unwrap_or_else(|| "Download Package".into()),
+        )
+        .with_input("packageType", self.package_type.as_ado_str())
+        .with_input("feed", self.feed)
+        .with_input("definition", self.definition)
+        .with_input("version", self.version)
+        .with_input("downloadPath", self.download_path);
+        push_opt(&mut t, "view", self.view);
+        push_opt(&mut t, "files", self.files);
+        if let Some(v) = self.extract {
+            t = t.with_input("extract", bool_input(v));
+        }
+        t
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn nuget_convenience_sets_required_inputs() {
+        let t = DownloadPackage::nuget(
+            "my-feed",
+            "my-package",
+            "1.2.3",
+            "$(System.ArtifactsDirectory)",
+        )
+        .into_step();
+        assert_eq!(t.task, "DownloadPackage@1");
+        assert_eq!(t.display_name, "Download Package");
+        assert_eq!(t.inputs.get("packageType").map(String::as_str), Some("nuget"));
+        assert_eq!(t.inputs.get("feed").map(String::as_str), Some("my-feed"));
+        assert_eq!(t.inputs.get("definition").map(String::as_str), Some("my-package"));
+        assert_eq!(t.inputs.get("version").map(String::as_str), Some("1.2.3"));
+        assert_eq!(
+            t.inputs.get("downloadPath").map(String::as_str),
+            Some("$(System.ArtifactsDirectory)")
+        );
+    }
+
+    #[test]
+    fn optional_inputs_emit_only_when_set() {
+        let t = DownloadPackage::nuget("feed", "pkg", "2.0.0", "$(Pipeline.Workspace)/out")
+            .view("Release")
+            .files("**/*.dll")
+            .extract(false)
+            .into_step();
+        assert_eq!(t.inputs.get("view").map(String::as_str), Some("Release"));
+        assert_eq!(t.inputs.get("files").map(String::as_str), Some("**/*.dll"));
+        assert_eq!(t.inputs.get("extract").map(String::as_str), Some("false"));
+    }
+
+    #[test]
+    fn optional_inputs_absent_when_not_set() {
+        let t = DownloadPackage::nuget("feed", "pkg", "1.0.0", "/tmp/out").into_step();
+        assert!(t.inputs.get("view").is_none());
+        assert!(t.inputs.get("files").is_none());
+        assert!(t.inputs.get("extract").is_none());
+    }
+
+    #[test]
+    fn display_name_override() {
+        let t = DownloadPackage::nuget("feed", "pkg", "1.0.0", "/tmp/out")
+            .with_display_name("Download my-package v1.0.0")
+            .into_step();
+        assert_eq!(t.display_name, "Download my-package v1.0.0");
+    }
+
+    #[test]
+    fn all_package_types_round_trip() {
+        let cases = [
+            (PackageType::NuGet, "nuget"),
+            (PackageType::Npm, "npm"),
+            (PackageType::PyPi, "pypi"),
+            (PackageType::Maven, "maven"),
+            (PackageType::UPack, "upack"),
+            (PackageType::Cargo, "cargo"),
+        ];
+        for (pt, expected) in cases {
+            let t = DownloadPackage::new(pt, "feed", "pkg", "1.0.0", "/out").into_step();
+            assert_eq!(t.inputs.get("packageType").map(String::as_str), Some(expected));
+        }
+    }
+}

src/compile/ir/tasks/mod.rs

@@ -26,6 +26,7 @@ pub mod delete_files;
 pub mod docker;
 pub mod docker_installer;
 pub mod dotnet_core_cli;
+pub mod download_package;
 pub mod download_pipeline_artifact;
 pub mod extract_files;
 pub mod npm;