implement TreeAny

Cargo.toml

@@ -1,18 +1,19 @@
 [package]
 name = "macroconf"
-version = "0.1.0"
+version = "0.2.0"
 edition = "2021"
 description = "macro for creating configurations using miniconf"
 license = "MIT OR Apache-2.0"
-repository = "https://git.mkaenner.de/max/macroconf.git"
+repository = "https://git.mkaenner.de/max/macroconf"
+readme = "README.md"
 categories = ["config", "embedded", "data-structures"]
 keywords = ["miniconf", "macro", "config"]
+authors = ["Max Känner <max.kaenner@gmail.com>"]
 
 [lints.rust]
 unsafe_code = "forbid"
 
 [lints.clippy]
-enum_glob_use = "deny"
 pedantic = "deny"
 nursery = "deny"
 cargo = "warn"
@@ -29,5 +30,5 @@ quote = "1.0"
 convert_case = "0.6.0"
 
 [dev-dependencies]
-miniconf = "0.9"
+miniconf = { version = "0.13", features = ["json-core"] }
 serde = "1.0"

src/lib.rs

@@ -1,8 +1,11 @@
+//! This crate creates `miniconf::Tree` implementations fields in a struct. These carry some extra
+//! extra information about the field.
+
 use std::iter::once;
 
 use convert_case::{Case, Casing};
 use proc_macro::TokenStream;
-use proc_macro2::{Span as Span2, TokenStream as TokenStream2};
+use proc_macro2::{Span as Span2, TokenStream as TokenStream2, TokenTree as TokenTree2};
 use quote::{format_ident, quote, ToTokens};
 use syn::{
     parse_macro_input, parse_quote, Attribute, DataStruct, DeriveInput, Expr, ExprLit, Field,
@@ -12,6 +15,20 @@ use syn::{
 /// Creates structs for the values to extend them with extra metadata.
 ///
 /// supported metadata is `min`, `max` and `default`. Doc comments are parsed as `description`
+///
+/// # Example
+/// ```
+/// use macroconf::config;
+///
+/// #[config]
+/// struct Config {
+///     /// This will be parsed as description
+///     #[min] // This will use i32::MIN for the minimum
+///     #[max = 50] // The value 50 is used for the maximum
+///     #[default = 42] // A `Default` implementation will be generated returning 42
+///     field1: i32,
+/// }
+/// ```
 #[proc_macro_attribute]
 pub fn config(_attr: TokenStream, item: TokenStream) -> TokenStream {
     let mut input = parse_macro_input!(item as DeriveInput);
@@ -37,6 +54,32 @@ pub fn config(_attr: TokenStream, item: TokenStream) -> TokenStream {
         }
     }
 
+    if let Some(attr) = input
+        .attrs
+        .iter_mut()
+        .find(|attr| attr.path().is_ident("derive"))
+    {
+        if let Ok(meta) = attr.meta.require_list() {
+            let derives_tree = meta
+                .tokens
+                .clone()
+                .into_iter()
+                .filter_map(|token| match token {
+                    TokenTree2::Ident(ident) if ident == Ident::new("Tree", ident.span()) => {
+                        Some(ident)
+                    }
+                    _ => None,
+                })
+                .count()
+                == 1;
+            if !derives_tree {
+                input.attrs.push(parse_quote!(#[derive(::miniconf::Tree)]));
+            }
+        }
+    } else {
+        input.attrs.push(parse_quote!(#[derive(::miniconf::Tree)]));
+    }
+
     quote! {
         #input
         #(#new_types)*
@@ -99,7 +142,7 @@ fn generate_helper_struct(
             .any(|key| attr.path().is_ident(key))
     });
 
-    field.attrs.push(parse_quote!(#[tree(depth(1))]));
+    field.attrs.push(parse_quote!(#[tree(depth=1)]));
     let vis = if matches!(field.vis, Visibility::Public(_))
         || matches!(field.vis, Visibility::Inherited)
     {
@@ -116,6 +159,7 @@ fn generate_helper_struct(
     let tree_key = generate_tree_key(&new_type_ident, new_type_miniconf_names.iter());
     let tree_serialize = generate_tree_serialize(&new_type_ident, &new_type_miniconf_consts[..]);
     let tree_deserialize = generate_tree_deserialize(&new_type_ident, miniconf_fields);
+    let tree_any = generate_tree_any(&new_type_ident, &new_type_miniconf_consts, miniconf_fields);
 
     Some(quote! {
         #[allow(clippy::derive_partial_eq_without_eq)]
@@ -130,6 +174,7 @@ fn generate_helper_struct(
         #tree_key
         #tree_serialize
         #tree_deserialize
+        #tree_any
     })
 }
 
@@ -339,7 +384,7 @@ fn generate_serde(ident: &Ident, ty: &Type, checked_new: bool) -> TokenStream2 {
     let conversion = if checked_new {
         quote! {
             Self::new(value).ok_or_else(|| {
-                D::Error::custom("checking value bounds")
+                <D::Error as ::serde::de::Error>::custom("checking value bounds")
             })
         }
     } else {
@@ -372,7 +417,7 @@ fn generate_serde(ident: &Ident, ty: &Type, checked_new: bool) -> TokenStream2 {
 
 fn generate_tree_key<'a>(
     ident: &Ident,
-    keys: impl Iterator<Item = &'a &'a str> + ExactSizeIterator + Clone,
+    keys: impl ExactSizeIterator<Item = &'a &'a str> + Clone,
 ) -> TokenStream2 {
     let keys = once(&"value").chain(keys);
     let num_keys = keys
@@ -381,32 +426,16 @@ fn generate_tree_key<'a>(
         .expect("safe because both iterators (once and original keys) are exact");
     let max_length = keys.clone().map(|v| v.len()).max();
     quote! {
-        impl #ident {
+        impl ::miniconf::KeyLookup for #ident {
-            const __MINICONF_NAMES: [&'static str; #num_keys] = [#(#keys,)*];
+            const LEN: usize = #num_keys;
+            const NAMES: &'static [&'static str] = &[#(#keys,)*];
+
+            fn name_to_index(value: &str) -> Option<usize> {
+                Self::NAMES.iter().position(|name| *name == value)
+            }
         }
 
         impl ::miniconf::TreeKey<1> for #ident {
-            fn name_to_index(name: &str) -> ::core::option::Option<usize> {
-                Self::__MINICONF_NAMES.iter().position(|&n| n == name)
-            }
-
-            fn traverse_by_key<K, F, E>(mut keys: K, mut func: F) -> ::core::result::Result<usize, ::miniconf::Error<E>>
-            where
-                K: ::core::iter::Iterator,
-                K::Item: ::miniconf::Key,
-                // Writing this to return an iterator instead of using a callback
-                // would have worse performance (O(n^2) instead of O(n) for matching)
-                F: FnMut(usize, &str) -> ::core::result::Result<(), E>,
-            {
-                let ::core::option::Option::Some(key) = keys.next() else { return ::core::result::Result::Ok(0) };
-                let index = ::miniconf::Key::find::<1, Self>(&key).ok_or(::miniconf::Error::NotFound(1))?;
-                let name = Self::__MINICONF_NAMES
-                    .get(index)
-                    .ok_or(::miniconf::Error::NotFound(1))?;
-                func(index, name)?;
-                ::miniconf::Increment::increment(::core::result::Result::Ok(0))
-            }
-
             fn metadata() -> miniconf::Metadata {
                 let mut metadata = miniconf::Metadata::default();
                 metadata.max_depth = 1;
@@ -414,6 +443,22 @@ fn generate_tree_key<'a>(
                 metadata.max_length = #max_length;
                 metadata
             }
+
+            fn traverse_by_key<K, F, E>(mut keys: K, mut func: F) -> ::core::result::Result<usize, ::miniconf::Error<E>>
+            where
+                K: ::miniconf::Keys,
+                // Writing this to return an iterator instead of using a callback
+                // would have worse performance (O(n^2) instead of O(n) for matching)
+                F: FnMut(usize, Option<&'static str>, usize) -> ::core::result::Result<(), E>,
+            {
+                let ::core::result::Result::Ok(key) = keys.next::<Self>() else { return ::core::result::Result::Ok(0) };
+                let index = ::miniconf::Key::find::<Self>(&key).ok_or(::miniconf::Traversal::NotFound(1))?;
+                let name = <Self as ::miniconf::KeyLookup>::NAMES
+                    .get(index)
+                    .ok_or(::miniconf::Traversal::NotFound(1))?;
+                func(index, Some(name), #num_keys).map_err(|err| ::miniconf::Error::Inner(1, err))?;
+                ::miniconf::Error::increment_result(::core::result::Result::Ok(0))
+            }
         }
     }
 }
@@ -422,7 +467,7 @@ fn generate_tree_serialize(ident: &Ident, consts: &[Ident]) -> TokenStream2 {
     let matches = consts.iter().enumerate().map(|(i, ident)| {
         let index = i + 1;
         quote! {
-            #index => ::miniconf::Serialize::serialize(&Self::#ident, ser)?,
+            #index => ::miniconf::Serialize::serialize(&Self::#ident, ser).map_err(|err| ::miniconf::Error::Inner(0, err))?,
         }
     });
     quote! {
@@ -433,23 +478,22 @@ fn generate_tree_serialize(ident: &Ident, consts: &[Ident]) -> TokenStream2 {
                 ser: S,
             ) -> ::core::result::Result<usize, ::miniconf::Error<S::Error>>
             where
-                K: ::core::iter::Iterator,
+                K: ::miniconf::Keys,
-                K::Item: ::miniconf::Key,
                 S: ::serde::Serializer,
             {
-                let ::core::option::Option::Some(key) = keys.next() else {
+                let ::core::result::Result::Ok(key) = keys.next::<Self>() else {
-                    return ::miniconf::Increment::increment({
+                    return ::miniconf::Error::increment_result({
-                        ::miniconf::Serialize::serialize(&self.0, ser)?;
+                        ::miniconf::Serialize::serialize(&self.0, ser).map_err(|err| ::miniconf::Error::Inner(0, err))?;
                         ::core::result::Result::Ok(0)
                     });
                 };
-                let index = ::miniconf::Key::find::<1, Self>(&key).ok_or(miniconf::Error::NotFound(1))?;
+                let index = ::miniconf::Key::find::<Self>(&key).ok_or(miniconf::Traversal::NotFound(1))?;
-                if keys.next().is_some() {
+                if !keys.finalize() {
-                    return ::core::result::Result::Err(::miniconf::Error::TooLong(1));
+                    ::core::result::Result::Err(::miniconf::Traversal::TooLong(1))?;
                 }
-                ::miniconf::Increment::increment({
+                ::miniconf::Error::increment_result({
                     match index {
-                        0 => ::miniconf::Serialize::serialize(&self.0, ser)?,
+                        0 => ::miniconf::Serialize::serialize(&self.0, ser).map_err(|err| ::miniconf::Error::Inner(0, err))?,
                         #(#matches)*
                         _ => unreachable!(),
                     };
@@ -469,24 +513,71 @@ fn generate_tree_deserialize(ident: &Ident, num_keys: usize) -> TokenStream2 {
                 de: D,
             ) -> ::core::result::Result<usize, ::miniconf::Error<D::Error>>
             where
-                K: ::core::iter::Iterator,
+                K: ::miniconf::Keys,
-                K::Item: ::miniconf::Key,
                 D: ::serde::Deserializer<'de>,
             {
-                let ::core::option::Option::Some(key) = keys.next() else {
+                let ::core::result::Result::Ok(key) = keys.next::<Self>() else {
-                    self.0 = ::miniconf::Deserialize::deserialize(de)?;
+                    self.0 = ::miniconf::Deserialize::deserialize(de).map_err(|err| ::miniconf::Error::Inner(0, err))?;
                     return ::core::result::Result::Ok(0);
                 };
-                let index = ::miniconf::Key::find::<1, Self>(&key).ok_or(::miniconf::Error::NotFound(1))?;
+                let index = ::miniconf::Key::find::<Self>(&key).ok_or(::miniconf::Traversal::NotFound(1))?;
-                if keys.next().is_some() {
+                if !keys.finalize() {
-                    return ::core::result::Result::Err(miniconf::Error::TooLong(1));
+                    ::core::result::Result::Err(::miniconf::Traversal::TooLong(1))?;
                 }
                 match index {
-                    0 => ::miniconf::Increment::increment({
+                    0 => ::miniconf::Error::increment_result((||{
-                        self.0 = ::miniconf::Deserialize::deserialize(de)?;
+                        self.0 = ::miniconf::Deserialize::deserialize(de).map_err(|err| ::miniconf::Error::Inner(0, err))?;
                         Ok(0)
-                    }),
+                    })()),
-                    1..=#num_keys => ::core::result::Result::Err(::miniconf::Error::Absent(0)),
+                    1..=#num_keys => ::core::result::Result::Err(::miniconf::Traversal::Absent(0))?,
+                    _ => unreachable!(),
+                }
+            }
+        }
+    }
+}
+
+fn generate_tree_any(ident: &Ident, consts: &[Ident], num_keys: usize) -> TokenStream2 {
+    let matches = consts.iter().enumerate().map(|(i, ident)| {
+        let index = i + 1;
+        quote! {
+            #index => ::core::result::Result::Ok(&Self::#ident),
+        }
+    });
+    quote! {
+        impl ::miniconf::TreeAny<1> for #ident {
+            fn ref_any_by_key<K>(&self, mut keys: K) -> ::core::result::Result<&dyn ::core::any::Any, ::miniconf::Traversal>
+            where
+                K: ::miniconf::Keys,
+            {
+                let ::core::result::Result::Ok(key) = keys.next::<Self>() else {
+                    return ::core::result::Result::Ok(&self.0);
+                };
+                let index = ::miniconf::Key::find::<Self>(&key).ok_or(miniconf::Traversal::NotFound(1))?;
+                if !keys.finalize() {
+                    ::core::result::Result::Err(::miniconf::Traversal::TooLong(1))?;
+                }
+                match index {
+                    0 => ::core::result::Result::Ok(&self.0),
+                    #(#matches)*
+                    _ => unreachable!(),
+                }
+            }
+
+            fn mut_any_by_key<K>(&mut self, mut keys: K) -> ::core::result::Result<&mut dyn ::core::any::Any, ::miniconf::Traversal>
+            where
+                K: ::miniconf::Keys,
+            {
+                let ::core::result::Result::Ok(key) = keys.next::<Self>() else {
+                    return ::core::result::Result::Ok(&mut self.0);
+                };
+                let index = ::miniconf::Key::find::<Self>(&key).ok_or(::miniconf::Traversal::NotFound(1))?;
+                if !keys.finalize() {
+                    ::core::result::Result::Err(::miniconf::Traversal::TooLong(1))?;
+                }
+                match index {
+                    0 => ::core::result::Result::Ok(&mut self.0),
+                    1..=#num_keys => ::core::result::Result::Err(::miniconf::Traversal::Absent(0)),
                     _ => unreachable!(),
                 }
             }

tests/simple.rs

@@ -1,11 +1,17 @@
 use std::str::from_utf8;
 
 use macroconf::config;
-use miniconf::{Error::Absent, JsonCoreSlash, Tree, TreeKey};
+use miniconf::{
+    Error::Traversal,
+    IntoKeys, JsonCoreSlash, Path,
+    Traversal::{Absent, TooLong},
+    Tree, TreeKey,
+};
+use serde::{Deserialize, Serialize};
 
 #[config]
-#[derive(Debug, Clone, Copy, Tree)]
+#[derive(Debug, Clone, Copy, Serialize, Deserialize, Tree)]
-struct Config {
+struct SubConfig {
     skipped: i32,
     #[min]
     min: i32,
@@ -17,6 +23,13 @@ struct Config {
     description: i32,
 }
 
+#[config]
+#[derive(Debug, Clone, Copy, Tree)]
+struct Config {
+    #[tree(depth = 2)]
+    sub_config: SubConfig,
+}
+
 #[test]
 fn keys() {
     for (id, field) in ["skipped", "min", "max", "default", "description"]
@@ -24,8 +37,8 @@ fn keys() {
         .enumerate()
     {
         assert_eq!(
-            Config::traverse_by_key(std::iter::once(field), |index, name| {
+            SubConfig::traverse_by_key([field].into_keys(), |index, name, _len| {
-                assert_eq!((id, field), (index, name));
+                assert_eq!((id, Some(field)), (index, name));
                 Ok::<_, ()>(())
             }),
             Ok(1)
@@ -36,16 +49,20 @@ fn keys() {
 #[test]
 fn sub_keys() {
     assert_eq!(
-        Config::traverse_by_key(["skipped", "value"].into_iter(), |_, _| Ok::<_, ()>(())),
+        SubConfig::traverse_by_key(["skipped", "value"].into_keys(), |_, _, _| Ok::<_, ()>(())),
+        Err(Traversal(TooLong(1)))
+    );
+    assert_eq!(
+        SubConfig::traverse_by_key(["skipped"].into_keys(), |_, _, _| Ok::<_, ()>(())),
         Ok(1)
     );
     for field in ["min", "max", "default", "description"] {
         assert_eq!(
-            Config::traverse_by_key([field, "value"].into_iter(), |_, _| Ok::<_, ()>(())),
+            SubConfig::traverse_by_key([field, "value"].into_keys(), |_, _, _| Ok::<_, ()>(())),
             Ok(2)
         );
         assert_eq!(
-            Config::traverse_by_key([field, field].into_iter(), |_, _| Ok::<_, ()>(())),
+            SubConfig::traverse_by_key([field, field].into_keys(), |_, _, _| Ok::<_, ()>(())),
             Ok(2)
         );
     }
@@ -54,12 +71,12 @@ fn sub_keys() {
 #[test]
 fn serialize() {
     let mut buffer = [0u8; 32];
-    let config = Config {
+    let config = SubConfig {
         skipped: 1,
-        min: __ConfigMin::new(2),
+        min: __SubConfigMin::new(2),
-        max: __ConfigMax::new(3),
+        max: __SubConfigMax::new(3),
-        default: __ConfigDefault::new(4),
+        default: __SubConfigDefault::new(4),
-        description: __ConfigDescription::new(5),
+        description: __SubConfigDescription::new(5),
     };
 
     for (input, output) in [
@@ -85,12 +102,12 @@ fn serialize() {
 
 #[test]
 fn deserialize() {
-    let mut config = Config {
+    let mut config = SubConfig {
         skipped: 0,
-        min: __ConfigMin::new(0),
+        min: __SubConfigMin::new(0),
-        max: __ConfigMax::new(0),
+        max: __SubConfigMax::new(0),
-        default: __ConfigDefault::new(0),
+        default: __SubConfigDefault::new(0),
-        description: __ConfigDescription::new(0),
+        description: __SubConfigDescription::new(0),
     };
 
     for input in [
@@ -115,6 +132,25 @@ fn deserialize() {
         "/description/description",
     ] {
         let res = config.set_json(input, b"10");
-        assert_eq!(res, Err(Absent(1)));
+        assert_eq!(res, Err(Traversal(Absent(1))));
     }
 }
+
+#[test]
+fn subconfig() {
+    let control = vec![
+        "/sub_config/skipped".to_owned(),
+        "/sub_config/min/value".to_owned(),
+        "/sub_config/min/min".to_owned(),
+        "/sub_config/max/value".to_owned(),
+        "/sub_config/max/max".to_owned(),
+        "/sub_config/default/value".to_owned(),
+        "/sub_config/default/default".to_owned(),
+        "/sub_config/description/value".to_owned(),
+        "/sub_config/description/description".to_owned(),
+    ];
+    let paths: Vec<String> = Config::nodes::<Path<String, '/'>>()
+        .filter_map(|path| path.ok().map(|(n, _)| n.0))
+        .collect();
+    assert_eq!(paths, control);
+}