Add enums to deepsize_derive, migrate to 2015 edition

Using the 2015 edition until rust-lang/rust#57407 is merged, so that the derive macro can be used within the crate (for tests)

Author: Aeledfyr

Cargo.toml

@@ -7,7 +7,7 @@ description = "A crate for measuring the total size of object on the stack and h
 repository = "https://github.com/Aeledfyr/deepsize/"
 readme = "README.md"
 include = ["Cargo.toml", "src/**/*.rs", "README.md", "LICENSE"]
-edition = "2018"
+edition = "2015"
 
 [dependencies]
 deepsize_derive = { path = "deepsize_derive", version = "0.1" }

deepsize_derive/Cargo.toml

@@ -6,7 +6,7 @@ license = "MIT"
 description = "A crate for measuring the total size of object on the stack and heap"
 repository = "https://github.com/Aeledfyr/deepsize/"
 include = ["Cargo.toml", "src/**/*.rs", "../LICENSE"]
-edition = "2018"
+edition = "2015"
 
 [lib]
 proc-macro = true

deepsize_derive/src/lib.rs

@@ -3,6 +3,9 @@
 /// Mainly from `syn`'s heap_size derive example:
 /// https://github.com/dtolnay/syn/commits/master/examples/heapsize/heapsize_derive/src/lib.rs
 extern crate proc_macro;
+extern crate proc_macro2;
+extern crate syn;
+extern crate quote;
 
 use proc_macro2::TokenStream;
 use quote::{quote, quote_spanned};
@@ -24,7 +27,7 @@ pub fn derive_deep_size(input: proc_macro::TokenStream) -> proc_macro::TokenStre
     let (impl_generics, ty_generics, where_clause) = generics.split_for_impl();
 
     // Generate an expression to sum up the size of each field.
-    let sum = deepsize_sum(&input.data);
+    let sum = deepsize_sum(&input.data, &name);
 
     let expanded = quote! {
         // The generated impl.
@@ -49,39 +52,119 @@ fn add_trait_bounds(mut generics: Generics) -> Generics {
     generics
 }
 
-// Generate an expression to sum up the size of each field.
-fn deepsize_sum(data: &Data) -> TokenStream {
-    match *data {
-        Data::Struct(ref data) => {
-            match data.fields {
-                Fields::Named(ref fields) => {
-                    let recurse = fields.named.iter().map(|f| {
-                        let name = &f.ident;
-                        quote_spanned! {f.span()=>
-                            ::deepsize::DeepSizeOf::deep_size_of_children(&self.#name, context)
-                        }
-                    });
-                    quote! {
-                        0 #(+ #recurse)*
-                    }
+fn match_fields(fields: &syn::Fields) -> TokenStream {
+    match fields {
+        Fields::Named(ref fields) => {
+            let recurse = fields.named.iter().map(|f| {
+                let name = &f.ident;
+                quote_spanned! {f.span()=>
+                    ::deepsize::DeepSizeOf::deep_size_of_children(&self.#name, context)
+                }
+            });
+            quote! {
+                0 #(+ #recurse)*
+            }
+        }
+        Fields::Unnamed(ref fields) => {
+            let recurse = fields.unnamed.iter().enumerate().map(|(i, f)| {
+                let index = Index::from(i);
+                quote_spanned! {f.span()=>
+                    ::deepsize::DeepSizeOf::deep_size_of_children(&self.#index, context)
+                }
+            });
+            quote! {
+                0 #(+ #recurse)*
+            }
+        }
+        Fields::Unit => {
+            // Unit structs cannot own more than 0 bytes of memory.
+            quote!(0)
+        }
+    }
+}
+
+fn match_enum_fields(fields: &syn::Fields) -> TokenStream {
+    match fields {
+        Fields::Named(ref fields) => {
+            let recurse = fields.named.iter().map(|f| {
+                let name = &f.ident;
+                quote_spanned! {f.span()=>
+                    ::deepsize::DeepSizeOf::deep_size_of_children(#name, context)
                 }
-                Fields::Unnamed(ref fields) => {
-                    let recurse = fields.unnamed.iter().enumerate().map(|(i, f)| {
-                        let index = Index::from(i);
-                        quote_spanned! {f.span()=>
-                            ::deepsize::DeepSizeOf::deep_size_of_children(&self.#index, context)
-                        }
-                    });
-                    quote! {
-                        0 #(+ #recurse)*
-                    }
+            });
+            quote! {
+                0 #(+ #recurse)*
+            }
+        }
+        Fields::Unnamed(ref fields) => {
+            let recurse = fields.unnamed.iter().enumerate().map(|(i, f)| {
+                let i = syn::Ident::new(&format!("_{}", i), proc_macro2::Span::call_site());
+                quote_spanned! {f.span()=>
+                    ::deepsize::DeepSizeOf::deep_size_of_children(#i, context)
                 }
-                Fields::Unit => {
-                    // Unit structs cannot own more than 0 bytes of memory.
-                    quote!(0)
+            });
+            quote! {
+                0 #(+ #recurse)*
+            }
+        }
+        Fields::Unit => {
+            // Unit structs cannot own more than 0 bytes of memory.
+            quote!(0)
+        }
+    }
+}
+
+fn get_matcher(var: &syn::Variant) -> TokenStream {
+    let matcher = match &var.fields {
+        Fields::Unit => TokenStream::new(),
+        Fields::Unnamed(fields) => {
+            let fields: TokenStream = (0..fields.unnamed.len())
+                .map(|n| {
+                    let i = syn::Ident::new(&format!("_{}", n), proc_macro2::Span::call_site());
+                    quote!(#i,)
+                })
+                .collect();
+            quote!((#fields))
+        }
+        Fields::Named(fields) => {
+            let fields: TokenStream = fields
+                .named
+                .iter()
+                .map(|f| {
+                    let i = f.ident.as_ref().unwrap();
+                    quote!(#i,)
+                })
+                .collect();
+            quote!({#fields})
+        }
+    };
+    
+    quote!(#matcher)
+}
+
+// Generate an expression to sum up the size of each field.
+fn deepsize_sum(data: &Data, struct_name: &proc_macro2::Ident) -> TokenStream {
+    match *data {
+        Data::Struct(ref inner) => {
+            match_fields(&inner.fields)
+        }
+        Data::Enum(ref inner) => {
+            let arms = inner.variants.iter()
+                .map(|var| {
+                    let matcher = get_matcher(var);
+                    let output = match_enum_fields(&var.fields);
+                    let name = &var.ident;
+                    let ident = quote!(#struct_name::#name);
+                    quote!(#ident #matcher => #output,)
+                });
+            
+            quote! {
+                match self {
+                    #(#arms)*
+                    _ => 0 // This is needed for empty enums
                 }
             }
         }
-        Data::Enum(_) | Data::Union(_) => unimplemented!(),
+        Data::Union(_) => unimplemented!(),
     }
 }

examples/derive.rs

@@ -1,3 +1,5 @@
+extern crate deepsize;
+
 use deepsize::DeepSizeOf;
 
 #[derive(DeepSizeOf)]

src/lib.rs

@@ -25,6 +25,13 @@
 //! ```
 //!
 
+// Hack so that #[derive(DeepSizeOf)] is usable within the crate
+// until [this](https://github.com/rust-lang/rust/pull/57407) stabalizes
+// Also means that both crates need to be on the 2015 edition
+mod deepsize { pub use super::*; }
+
+extern crate deepsize_derive;
+
 pub use deepsize_derive::*;
 
 use std::collections::HashSet;
@@ -73,7 +80,7 @@ pub trait DeepSizeOf {
     /// This is an internal function, and requires a [`Context`](Context)
     /// to track visited references.
     fn recurse_deep_size_of(&self, context: &mut Context) -> usize {
-        self.stack_size() + self.deep_size_of_children(context)
+        std::mem::size_of_val(self) + self.deep_size_of_children(context)
     }
 
     /// Returns an estimation of a total size of memory owned by the
@@ -85,13 +92,6 @@ pub trait DeepSizeOf {
     /// This is an internal function, and requires a [`Context`](Context)
     /// to track visited references.
     fn deep_size_of_children(&self, context: &mut Context) -> usize;
-
-    /// Returns the size of the memory the object uses itself
-    ///
-    /// This method is generally equivalent to [`size_of_val`](std::mem::size_of_val)
-    fn stack_size(&self) -> usize {
-        std::mem::size_of_val(self)
-    }
 }
 
 
@@ -198,8 +198,8 @@ where
     /// ```
     fn deep_size_of_children(&self, context: &mut Context) -> usize {
         self.iter()
-            .fold(0, |sum, child| sum + child.recurse_deep_size_of(context))
-         + (self.capacity() - self.len()) * std::mem::size_of::<T>()
+            .fold(0, |sum, child| sum + child.deep_size_of_children(context))
+         + self.capacity() * std::mem::size_of::<T>()
         // Size of unused capacity
     }
 }
@@ -241,8 +241,8 @@ where
     /// ```
     fn deep_size_of_children(&self, context: &mut Context) -> usize {
         self.iter()
-            .fold(0, |sum, child| sum + child.recurse_deep_size_of(context))
-         + (self.capacity() - self.len()) * std::mem::size_of::<T>()
+            .fold(0, |sum, child| sum + child.deep_size_of_children(context))
+         + self.capacity() * std::mem::size_of::<T>()
         // Size of unused capacity
     }
 }
@@ -287,10 +287,9 @@ where
             .fold(0, |sum, (key, val)| {
                 sum + key.deep_size_of_children(context)
                     + val.deep_size_of_children(context)
-                    + std::mem::size_of::<Option<(u64, K, V)>>()
             })
-         + (self.capacity() - self.len()) * (std::mem::size_of::<Option<(u64, K, V)>>())
-        // Size of unused capacity
+         + self.capacity() * std::mem::size_of::<Option<(u64, K, V)>>()
+        // Size of container capacity
     }
 }
 
@@ -302,10 +301,9 @@ where
         self.iter()
             .fold(0, |sum, item| {
                 sum + item.deep_size_of_children(context)
-                    + std::mem::size_of::<Option<(u64, T, ())>>()
             })
-         + (self.capacity() - self.len()) * (std::mem::size_of::<Option<(u64, T, ())>>())
-        // Size of unused capacity
+         + self.capacity() * std::mem::size_of::<Option<(u64, T, ())>>()
+        // Size container storage
     }
 }
 
@@ -331,10 +329,10 @@ where
 
     fn recurse_deep_size_of(&self, context: &mut Context) -> usize {
         if context.contains_arc(self) {
-            self.stack_size()
+            std::mem::size_of::<Self>()
         } else {
             context.add_arc(self);
-            self.stack_size() + self.deep_size_of_children(context)
+            std::mem::size_of::<Self>() + self.deep_size_of_children(context)
         }
     }
 }
@@ -350,10 +348,10 @@ where
 
     fn recurse_deep_size_of(&self, context: &mut Context) -> usize {
         if context.contains_rc(self) {
-            self.stack_size()
+            std::mem::size_of::<Self>()
         } else {
             context.add_rc(self);
-            self.stack_size() + self.deep_size_of_children(context)
+            std::mem::size_of::<Self>() + self.deep_size_of_children(context)
         }
     }
 }
@@ -373,10 +371,10 @@ where
 
     fn recurse_deep_size_of(&self, context: &mut Context) -> usize {
         if context.contains_ref(&self) {
-            self.stack_size()
+            std::mem::size_of::<Self>()
         } else {
             context.add_ref(&self);
-            self.stack_size() + self.deep_size_of_children(context)
+            std::mem::size_of::<Self>() + self.deep_size_of_children(context)
         }
     }
 }
@@ -387,10 +385,6 @@ where
 {
     fn deep_size_of_children(&self, context: &mut Context) -> usize {
         self.iter()
-            .fold(0, |sum, child| sum + child.recurse_deep_size_of(context))
-    }
-
-    fn stack_size(&self) -> usize {
-        0
+            .fold(0, |sum, child| sum + child.deep_size_of_children(context))
     }
 }

src/test.rs

@@ -54,10 +54,10 @@ fn alignment() {
     assert_eq!(std::mem::size_of::<[Test; 3]>(), array.deep_size_of());
 
     let vec = vec![Test(5), Test(16), Test(2)];
-    assert_eq!(array.deep_size_of(), 256 * 3);
+    assert_eq!(vec.deep_size_of(), 256 * 3 + 24);
 
     let vec = vec![Test2(Test(5), 0), Test2(Test(16), 0), Test2(Test(2), 0)];
-    assert_eq!(array.deep_size_of(), 256 * 3);
+    assert_eq!(vec.deep_size_of(), 512 * 3 + 24);
 }
 
 mod context_tests {
@@ -94,3 +94,14 @@ mod context_tests {
     }
 }
 
+fn test_derive() {
+    
+    #[derive(DeepSizeOf)]
+    enum Example {
+        One,
+        Two(),
+        Three(u32, Box<u8>),
+        Four { name: Box<u32> },
+        Five { },
+    }
+}