mashin_macro 0.1.4

Proc macro for writing mashin resources
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118

/* -------------------------------------------------------- *\
 *                                                          *
 *      ███╗░░░███╗░█████╗░░██████╗██╗░░██╗██╗███╗░░██╗     *
 *      ████╗░████║██╔══██╗██╔════╝██║░░██║██║████╗░██║     *
 *      ██╔████╔██║███████║╚█████╗░███████║██║██╔██╗██║     *
 *      ██║╚██╔╝██║██╔══██║░╚═══██╗██╔══██║██║██║╚████║     *
 *      ██║░╚═╝░██║██║░░██║██████╔╝██║░░██║██║██║░╚███║     *
 *      ╚═╝░░░░░╚═╝╚═╝░░╚═╝╚═════╝░╚═╝░░╚═╝╚═╝╚═╝░░╚══╝     *
 *                                         by Nutshimit     *
 * -------------------------------------------------------- *
 *                                                          *
 *   This file is dual-licensed as Apache-2.0 or GPL-3.0.   *
 *   see LICENSE for license details.                       *
 *                                                          *
\* ---------------------------------------------------------*/

use darling::ToTokens;

pub trait MutItemAttrs {
	fn mut_item_attrs(&mut self) -> Option<&mut Vec<syn::Attribute>>;
}

pub fn _take_item_provider_attrs<Attr>(item: &mut impl MutItemAttrs) -> syn::Result<Vec<Attr>>
where
	Attr: syn::parse::Parse,
{
	let mut pallet_attrs = Vec::new();

	while let Some(attr) = take_first_item_provider_attr(item)? {
		pallet_attrs.push(attr)
	}

	Ok(pallet_attrs)
}

/// Take the first mashin attribute (e.g. attribute like `#[mashin..]`) and decode it to `Attr`
pub fn take_first_item_provider_attr<Attr>(
	item: &mut impl MutItemAttrs,
) -> syn::Result<Option<Attr>>
where
	Attr: syn::parse::Parse,
{
	let attrs = if let Some(attrs) = item.mut_item_attrs() { attrs } else { return Ok(None) };

	if let Some(index) = attrs.iter().position(|attr| {
		attr.path.segments.first().map_or(false, |segment| segment.ident == "mashin")
	}) {
		let pallet_attr = attrs.remove(index);
		Ok(Some(syn::parse2(pallet_attr.into_token_stream())?))
	} else {
		Ok(None)
	}
}

impl MutItemAttrs for syn::Item {
	fn mut_item_attrs(&mut self) -> Option<&mut Vec<syn::Attribute>> {
		match self {
			Self::Const(item) => Some(item.attrs.as_mut()),
			Self::Enum(item) => Some(item.attrs.as_mut()),
			Self::ExternCrate(item) => Some(item.attrs.as_mut()),
			Self::Fn(item) => Some(item.attrs.as_mut()),
			Self::ForeignMod(item) => Some(item.attrs.as_mut()),
			Self::Impl(item) => Some(item.attrs.as_mut()),
			Self::Macro(item) => Some(item.attrs.as_mut()),
			Self::Macro2(item) => Some(item.attrs.as_mut()),
			Self::Mod(item) => Some(item.attrs.as_mut()),
			Self::Static(item) => Some(item.attrs.as_mut()),
			Self::Struct(item) => Some(item.attrs.as_mut()),
			Self::Trait(item) => Some(item.attrs.as_mut()),
			Self::TraitAlias(item) => Some(item.attrs.as_mut()),
			Self::Type(item) => Some(item.attrs.as_mut()),
			Self::Union(item) => Some(item.attrs.as_mut()),
			Self::Use(item) => Some(item.attrs.as_mut()),
			_ => None,
		}
	}
}

impl MutItemAttrs for syn::TraitItem {
	fn mut_item_attrs(&mut self) -> Option<&mut Vec<syn::Attribute>> {
		match self {
			Self::Const(item) => Some(item.attrs.as_mut()),
			Self::Method(item) => Some(item.attrs.as_mut()),
			Self::Type(item) => Some(item.attrs.as_mut()),
			Self::Macro(item) => Some(item.attrs.as_mut()),
			_ => None,
		}
	}
}

impl MutItemAttrs for Vec<syn::Attribute> {
	fn mut_item_attrs(&mut self) -> Option<&mut Vec<syn::Attribute>> {
		Some(self)
	}
}

impl MutItemAttrs for syn::ItemMod {
	fn mut_item_attrs(&mut self) -> Option<&mut Vec<syn::Attribute>> {
		Some(&mut self.attrs)
	}
}

impl MutItemAttrs for syn::ImplItemMethod {
	fn mut_item_attrs(&mut self) -> Option<&mut Vec<syn::Attribute>> {
		Some(&mut self.attrs)
	}
}
impl MutItemAttrs for syn::ImplItem {
	fn mut_item_attrs(&mut self) -> Option<&mut Vec<syn::Attribute>> {
		match self {
			syn::ImplItem::Const(i) => Some(i.attrs.as_mut()),
			syn::ImplItem::Method(i) => Some(i.attrs.as_mut()),
			syn::ImplItem::Type(i) => Some(i.attrs.as_mut()),
			syn::ImplItem::Macro(i) => Some(i.attrs.as_mut()),
			_ => None,
		}
	}
}