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-rw-r--r--macros/src/util/mod.rs1
-rw-r--r--macros/src/util/tokens.rs89
2 files changed, 90 insertions, 0 deletions
diff --git a/macros/src/util/mod.rs b/macros/src/util/mod.rs
index d3edb67..2244229 100644
--- a/macros/src/util/mod.rs
+++ b/macros/src/util/mod.rs
@@ -3,6 +3,7 @@ pub mod item_impl;
pub mod iterator_ext;
pub mod string;
pub mod syn_path;
+pub mod tokens;
macro_rules! to_option {
($($tokens: tt)+) => {
diff --git a/macros/src/util/tokens.rs b/macros/src/util/tokens.rs
new file mode 100644
index 0000000..c614ea0
--- /dev/null
+++ b/macros/src/util/tokens.rs
@@ -0,0 +1,89 @@
+use std::fmt::Write;
+
+use proc_macro2::{Delimiter, Spacing, TokenTree};
+use quote::ToTokens;
+
+pub trait ToTokensExt
+{
+ fn to_str_pretty(&self) -> String;
+}
+
+impl<T: ToTokens> ToTokensExt for T
+{
+ fn to_str_pretty(&self) -> String
+ {
+ let mut spaceable = Spaceable::None;
+
+ self.to_token_stream()
+ .into_iter()
+ .fold(String::new(), |mut acc, token_tree| {
+ let prev_spaceable = spaceable;
+
+ spaceable = get_tt_spaceable(&token_tree);
+
+ if matches!(prev_spaceable, Spaceable::Left | Spaceable::LeftRight)
+ && matches!(spaceable, Spaceable::Right | Spaceable::LeftRight)
+ {
+ write!(acc, " ").ok();
+ }
+
+ match token_tree {
+ TokenTree::Group(group) => match group.delimiter() {
+ Delimiter::Parenthesis => {
+ write!(acc, "({})", group.stream().to_str_pretty()).ok();
+ }
+ Delimiter::Brace => {
+ write!(acc, "{{{}}}", group.stream().to_str_pretty()).ok();
+ }
+ Delimiter::Bracket => {
+ write!(acc, "[{}]", group.stream().to_str_pretty()).ok();
+ }
+ Delimiter::None => {
+ write!(acc, "{}", group.stream().to_str_pretty()).ok();
+ }
+ },
+ tt => {
+ write!(acc, "{tt}").ok();
+ }
+ }
+
+ acc
+ })
+ }
+}
+
+fn get_tt_spaceable(token_tree: &TokenTree) -> Spaceable
+{
+ match &token_tree {
+ TokenTree::Ident(_) => Spaceable::LeftRight,
+ TokenTree::Punct(punct)
+ if punct.spacing() == Spacing::Alone && (punct.as_char() == '+') =>
+ {
+ Spaceable::LeftRight
+ }
+ TokenTree::Punct(punct)
+ if punct.spacing() == Spacing::Alone
+ && (punct.as_char() == '>' || punct.as_char() == ',') =>
+ {
+ Spaceable::Left
+ }
+ TokenTree::Punct(punct)
+ if punct.spacing() == Spacing::Joint && punct.as_char() == '-' =>
+ {
+ // Is part of ->
+ Spaceable::Right
+ }
+ TokenTree::Punct(punct) if punct.as_char() == '&' => Spaceable::Right,
+ TokenTree::Group(_) => Spaceable::Left,
+ _ => Spaceable::None,
+ }
+}
+
+#[derive(Debug, Clone, Copy)]
+enum Spaceable
+{
+ Left,
+ Right,
+ LeftRight,
+ None,
+}