feat: dagrunner, initial version

src/deps.rs

@@ -0,0 +1,114 @@
+//! Dependency tuple trait and implementations.
+//!
+//! This module defines the DepsTuple trait that allows specifying dependencies in
+//! various forms (handles, builders, tuples). It uses macro-generated implementations
+//! for different tuple sizes.
+//!
+//! This trait is internal and not meant for external implementation. Users should only
+//! use the provided implementations.
+
+use crate::builder::TaskBuilder;
+use crate::task::Task;
+use crate::types::{NodeId, TaskHandle};
+
+pub(crate) trait DepsTuple<Input> {
+    fn to_node_ids(&self) -> Vec<NodeId>;
+}
+
+// Implementation for unit (no dependencies)
+impl DepsTuple<()> for () {
+    fn to_node_ids(&self) -> Vec<NodeId> {
+        Vec::new()
+    }
+}
+
+// Implementation for single dependency (all forms)
+impl<T> DepsTuple<T> for &TaskHandle<T> {
+    fn to_node_ids(&self) -> Vec<NodeId> {
+        vec![self.id]
+    }
+}
+
+impl<T> DepsTuple<T> for TaskHandle<T> {
+    fn to_node_ids(&self) -> Vec<NodeId> {
+        vec![self.id]
+    }
+}
+
+impl<T> DepsTuple<T> for (&TaskHandle<T>,) {
+    fn to_node_ids(&self) -> Vec<NodeId> {
+        vec![self.0.id]
+    }
+}
+
+impl<T> DepsTuple<T> for (TaskHandle<T>,) {
+    fn to_node_ids(&self) -> Vec<NodeId> {
+        vec![self.0.id]
+    }
+}
+
+// Support for &TaskBuilder
+impl<'a, Tk: Task, Deps> DepsTuple<Tk::Output> for &TaskBuilder<'a, Tk, Deps> {
+    fn to_node_ids(&self) -> Vec<NodeId> {
+        vec![self.id]
+    }
+}
+
+impl<'a, Tk: Task, Deps> DepsTuple<Tk::Output> for (&TaskBuilder<'a, Tk, Deps>,) {
+    fn to_node_ids(&self) -> Vec<NodeId> {
+        vec![self.0.id]
+    }
+}
+
+/// Macro to implement DepsTuple for different tuple sizes.
+///
+/// This macro exists because Rust lacks variadic generics - we need separate implementations
+/// for each tuple size.
+///
+/// For each tuple size, generates two implementations:
+/// - `(&TaskHandle<A>, &TaskHandle<B>, ...)` → `DepsTuple<(A, B, ...)>`
+/// - `(&TaskBuilder<TkA, _>, &TaskBuilder<TkB, _>, ...)` → `DepsTuple<(TkA::Output, TkB::Output, ...)>`
+///
+/// This allows flexible dependency specification:
+/// ```ignore
+/// // Using handles
+/// task.depends_on((&handle_a, &handle_b))
+///
+/// // Using builders directly
+/// task.depends_on((&dag.add_task(TaskA), &dag.add_task(TaskB)))
+/// ```
+macro_rules! impl_deps_tuple {
+    ($($T:ident : $Tk:ident : $D:ident),+) => {
+        // For &TaskHandle tuples
+        impl<$($T),+> DepsTuple<($($T,)+)> for ($(&TaskHandle<$T>,)+) {
+            #[allow(non_snake_case)]
+            fn to_node_ids(&self) -> Vec<NodeId> {
+                let ($($T,)+) = self;
+                vec![$($T.id,)+]
+            }
+        }
+
+        // For &TaskBuilder tuples
+        impl<'a, $($Tk: Task, $D),+> DepsTuple<($($Tk::Output,)+)> for ($(&TaskBuilder<'a, $Tk, $D>,)+) {
+            #[allow(non_snake_case)]
+            fn to_node_ids(&self) -> Vec<NodeId> {
+                let ($($T,)+) = self;
+                vec![$($T.id,)+]
+            }
+        }
+    };
+}
+
+// Generate DepsTuple implementations for tuples of size 2-8.
+// Each invocation generates 2 implementations (TaskHandle refs and TaskBuilder refs).
+// Supporting up to 8 elements covers the vast majority of use cases.
+impl_deps_tuple!(A:TkA:DA, B:TkB:DB);
+impl_deps_tuple!(A:TkA:DA, B:TkB:DB, C:TkC:DC);
+impl_deps_tuple!(A:TkA:DA, B:TkB:DB, C:TkC:DC, D:TkD:DD);
+impl_deps_tuple!(A:TkA:DA, B:TkB:DB, C:TkC:DC, D:TkD:DD, E:TkE:DE);
+impl_deps_tuple!(A:TkA:DA, B:TkB:DB, C:TkC:DC, D:TkD:DD, E:TkE:DE, F:TkF:DF);
+impl_deps_tuple!(A:TkA:DA, B:TkB:DB, C:TkC:DC, D:TkD:DD, E:TkE:DE, F:TkF:DF, G:TkG:DG);
+impl_deps_tuple!(A:TkA:DA, B:TkB:DB, C:TkC:DC, D:TkD:DD, E:TkE:DE, F:TkF:DF, G:TkG:DG, H:TkH:DH);
+
+#[cfg(test)]
+mod tests;