Pretty type names in graphviz dump, bring back PartialEq/NodeValue impl

crates/compute_graph/Cargo.toml

@@ -8,6 +8,8 @@ edition = "2021"
 [dependencies]
 compute_graph_macros = { path = "../compute_graph_macros" }
 petgraph = "0.6.5"
+syn = "2"
+quote = "1"
 
 [dev-dependencies]
 tokio = { version = "1.41.0", features = ["rt", "macros"] }

crates/compute_graph/src/lib.rs

@@ -618,11 +618,6 @@ mod tests {
     fn non_cloneable_output() {
         #[derive(PartialEq, Debug)]
         struct NonCloneable;
-        impl NodeValue for NonCloneable {
-            fn node_value_eq(&self, _other: &Self) -> bool {
-                true
-            }
-        }
         struct Output;
         impl InputVisitable for Output {
             fn visit_inputs(&self, _visitor: &mut impl InputVisitor) {}

crates/compute_graph/src/node.rs

@@ -1,5 +1,6 @@
 use crate::synchronicity::{Asynchronous, Synchronicity};
 use crate::{AsyncRule, Input, InputVisitor, NodeId, Rule, Synchronous};
+use quote::ToTokens;
 use std::any::Any;
 use std::cell::RefCell;
 use std::future::Future;
@@ -85,13 +86,16 @@ pub(crate) trait Node<Value: NodeValue, Synch: Synchronicity>: std::fmt::Debug {
 ///
 /// This trait is used to determine, when a node is invalidated, whether its value has truly changed
 /// and thus whether downstream nodes need to be invalidated too.
+///
+/// A blanket implementation of this trait for all types implementing `PartialEq` is provided.
 pub trait NodeValue: 'static {
     /// Whether self is equal, for the purposes of graph invalidation, from other.
     ///
     /// This method should be conservative. That is, if the equality of the two values cannot be affirmatively
     /// determined, this method should return `false`.
     ///
-    /// The default implementation of this method always returns `false`.
+    /// The default implementation of this method always returns `false`, so any non-`PartialEq` type can
+    /// implement this trait simply:
     ///
     /// ```rust
     /// # use compute_graph::node::NodeValue;
@@ -106,36 +110,12 @@ pub trait NodeValue: 'static {
     }
 }
 
-impl NodeValue for () {
-    fn node_value_eq(&self, _other: &Self) -> bool {
-        true
-    }
-}
-
-impl NodeValue for i32 {
+impl<T: PartialEq + 'static> NodeValue for T {
     fn node_value_eq(&self, other: &Self) -> bool {
         self == other
     }
 }
 
-impl<T: NodeValue> NodeValue for Option<T> {
-    fn node_value_eq(&self, other: &Self) -> bool {
-        match (self, other) {
-            (Some(s), Some(o)) => s.node_value_eq(o),
-            _ => false,
-        }
-    }
-}
-
-impl<T: NodeValue, E: 'static> NodeValue for Result<T, E> {
-    fn node_value_eq(&self, other: &Self) -> bool {
-        match (self, other) {
-            (Ok(s), Ok(o)) => s.node_value_eq(o),
-            _ => false,
-        }
-    }
-}
-
 pub(crate) struct ConstNode<V, S> {
     value: Rc<RefCell<Option<V>>>,
     synchronicity: std::marker::PhantomData<S>,
@@ -170,7 +150,7 @@ impl<V: NodeValue, S: Synchronicity> Node<V, S> for ConstNode<V, S> {
 
 impl<V, S> std::fmt::Debug for ConstNode<V, S> {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        write!(f, "ConstNode<{}>", std::any::type_name::<V>())
+        write!(f, "ConstNode<{}>", pretty_type_name::<V>())
     }
 }
 
@@ -215,7 +195,7 @@ impl<V: NodeValue, S: Synchronicity> Node<V, S> for InvalidatableConstNode<V, S>
 
 impl<V, S> std::fmt::Debug for InvalidatableConstNode<V, S> {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        write!(f, "InvalidatableConstNode<{}>", std::any::type_name::<V>())
+        write!(f, "InvalidatableConstNode<{}>", pretty_type_name::<V>())
     }
 }
 
@@ -289,7 +269,7 @@ impl<R: Rule, V, S> std::fmt::Debug for RuleNode<R, V, S> {
         write!(
             f,
             "RuleNode<{}>({})",
-            std::any::type_name::<R>(),
+            pretty_type_name::<R>(),
             RuleLabel(&self.rule)
         )
     }
@@ -343,7 +323,7 @@ impl<V: NodeValue, P: FnOnce() -> F, F: Future<Output = V>> Node<V, Asynchronous
 
 impl<V, P: FnOnce() -> F, F: Future<Output = V>> std::fmt::Debug for AsyncConstNode<V, P, F> {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        write!(f, "AsyncConstNode<{}>", std::any::type_name::<V>())
+        write!(f, "AsyncConstNode<{}>", pretty_type_name::<V>())
     }
 }
 
@@ -419,8 +399,53 @@ impl<R: AsyncRule, V> std::fmt::Debug for AsyncRuleNode<R, V> {
         write!(
             f,
             "AsyncRuleNode<{}>({})",
-            std::any::type_name::<R>(),
+            pretty_type_name::<R>(),
             AsyncRuleLabel(&self.rule)
         )
     }
 }
+
+fn pretty_type_name<T>() -> String {
+    let s = std::any::type_name::<T>();
+    let ty = syn::parse_str::<syn::Type>(s).unwrap();
+    pretty_type_name_type(ty)
+}
+
+fn pretty_type_name_type(ty: syn::Type) -> String {
+    match ty {
+        syn::Type::Path(path) => pretty_type_name_path(path),
+        _ => format!("{}", ty.into_token_stream()),
+    }
+}
+
+fn pretty_type_name_path(path: syn::TypePath) -> String {
+    if path.qself.is_some() {
+        format!("{}", path.into_token_stream())
+    } else {
+        let last_segment = path.path.segments.last().unwrap();
+        match &last_segment.arguments {
+            syn::PathArguments::None => {
+                format!("{}", last_segment.ident.to_token_stream())
+            }
+            syn::PathArguments::AngleBracketed(args) => {
+                let mut str = format!("{}", last_segment.ident.to_token_stream());
+                str.push('<');
+                for arg in &args.args {
+                    match arg {
+                        syn::GenericArgument::Type(ty) => {
+                            str.push_str(&pretty_type_name_type(ty.clone()))
+                        }
+                        _ => str.push_str(&format!("{}", arg.into_token_stream())),
+                    }
+                    str.push_str(", ")
+                }
+                str.remove(str.len() - 1);
+                str.replace_range((str.len() - 1).., ">");
+                str
+            }
+            syn::PathArguments::Parenthesized(_) => {
+                format!("{}", last_segment.into_token_stream())
+            }
+        }
+    }
+}