feat: add project & for_each_opengl_command macro

1 files changed, 263 insertions, 0 deletions

diff --git a/src/token_stream.rs b/src/token_stream.rs
new file mode 100644
index 0000000..043de89
--- /dev/null
+++ b/src/token_stream.rs
@@ -0,0 +1,263 @@
+use proc_macro2::{Group, Ident, TokenStream, TokenTree};
+
+pub use self::index_path::IndexPath;
+
+#[allow(clippy::module_name_repetitions)]
+pub trait TokenStreamExt
+{
+    fn find_all_ident(&self, target_ident: &Ident) -> Vec<IndexPath>;
+
+    fn replace_tokens(
+        &self,
+        index_paths_to_replace: &[IndexPath],
+        substitution: &TokenTree,
+    ) -> TokenStream;
+}
+
+impl TokenStreamExt for TokenStream
+{
+    fn find_all_ident(&self, target_ident: &Ident) -> Vec<IndexPath>
+    {
+        let mut found_indices = Vec::new();
+
+        recurse_find_all_ident(
+            self.clone(),
+            target_ident,
+            &mut found_indices,
+            &IndexPath::new(),
+        );
+
+        found_indices
+    }
+
+    fn replace_tokens(
+        &self,
+        index_paths_to_replace: &[IndexPath],
+        substitution: &TokenTree,
+    ) -> TokenStream
+    {
+        self.clone()
+            .into_iter()
+            .enumerate()
+            .map(|(index, mut token_tree)| {
+                for index_path in index_paths_to_replace
+                    .iter()
+                    .filter(|path| path.indices()[0] == index)
+                {
+                    token_tree = match token_tree {
+                        TokenTree::Ident(_) => substitution.clone(),
+                        TokenTree::Group(group) => TokenTree::Group(Group::new(
+                            group.delimiter(),
+                            recurse_replace_tokens(
+                                group.stream(),
+                                substitution,
+                                &index_path.indices()[1..],
+                            ),
+                        )),
+                        tt => tt,
+                    }
+                }
+
+                token_tree
+            })
+            .collect()
+    }
+}
+
+fn recurse_find_all_ident(
+    input_stream: TokenStream,
+    target_ident: &Ident,
+    found_indices: &mut Vec<IndexPath>,
+    current_index_path: &IndexPath,
+)
+{
+    for (index, token_tree) in input_stream.into_iter().enumerate() {
+        match token_tree {
+            TokenTree::Ident(ident) if &ident == target_ident => {
+                let mut index_path = current_index_path.clone();
+
+                index_path.push_index(index);
+
+                found_indices.push(index_path);
+            }
+            TokenTree::Group(group) => {
+                let mut index_path = current_index_path.clone();
+
+                index_path.push_index(index);
+
+                recurse_find_all_ident(
+                    group.stream(),
+                    target_ident,
+                    found_indices,
+                    &index_path,
+                );
+            }
+            _ => {}
+        }
+    }
+}
+
+fn recurse_replace_tokens(
+    token_stream: TokenStream,
+    substitution: &TokenTree,
+    indices: &[usize],
+) -> TokenStream
+{
+    token_stream
+        .into_iter()
+        .enumerate()
+        .map(|(index, token_tree)| match token_tree {
+            TokenTree::Ident(_) if index == indices[0] => substitution.clone(),
+            TokenTree::Group(group) if index == indices[0] => {
+                TokenTree::Group(Group::new(
+                    group.delimiter(),
+                    recurse_replace_tokens(group.stream(), substitution, &indices[1..]),
+                ))
+            }
+            tt => tt,
+        })
+        .collect()
+}
+
+mod index_path
+{
+    #[derive(Debug, Clone, PartialEq, Eq)]
+    pub struct IndexPath
+    {
+        indices: Vec<usize>,
+    }
+
+    impl IndexPath
+    {
+        pub fn new() -> Self
+        {
+            Self {
+                indices: Vec::new(),
+            }
+        }
+
+        pub fn push_index(&mut self, index: usize)
+        {
+            self.indices.push(index);
+        }
+
+        pub fn indices(&self) -> &[usize]
+        {
+            &self.indices
+        }
+    }
+
+    impl<IntoIter> From<IntoIter> for IndexPath
+    where
+        IntoIter: IntoIterator<Item = usize>,
+    {
+        fn from(value: IntoIter) -> Self
+        {
+            Self {
+                indices: value.into_iter().collect(),
+            }
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests
+{
+    use proc_macro2::Span;
+    use quote::quote;
+
+    use super::*;
+
+    #[test]
+    fn find_all_ident_works()
+    {
+        assert_eq!(
+            quote! {
+                let abc = xyz;
+            }
+            .find_all_ident(&Ident::new("xyz", Span::call_site())),
+            vec![IndexPath::from([3])]
+        );
+
+        assert_eq!(
+            quote! {
+                let abc = (xyz, "123");
+            }
+            .find_all_ident(&Ident::new("xyz", Span::call_site())),
+            vec![IndexPath::from([3, 0])]
+        );
+
+        assert_eq!(
+            quote! {
+                return ("123", (yo, 180, xyz));
+            }
+            .find_all_ident(&Ident::new("xyz", Span::call_site())),
+            vec![IndexPath::from([1, 2, 4])]
+        );
+    }
+
+    #[test]
+    fn find_all_ident_works_with_multiple()
+    {
+        assert_eq!(
+            quote! {
+                unsafe {
+                    functions::xyz = FunctionPtr::new_initialized(
+                        get_proc_addr(stringify!(xyz))
+                    );
+                }
+            }
+            .find_all_ident(&Ident::new("xyz", Span::call_site()),),
+            vec![IndexPath::from([1, 3]), IndexPath::from([1, 9, 1, 2, 0])]
+        );
+    }
+
+    #[test]
+    fn recurse_replace_tokens_works()
+    {
+        assert_eq!(
+            recurse_replace_tokens(
+                quote! {
+                    let abc = xyz;
+                },
+                &TokenTree::Ident(Ident::new("foo", Span::call_site())),
+                &[3]
+            )
+            .to_string(),
+            quote! {
+                let abc = foo;
+            }
+            .to_string()
+        );
+
+        assert_eq!(
+            recurse_replace_tokens(
+                quote! {
+                    let abc = (xyz, "123");
+                },
+                &TokenTree::Ident(Ident::new("foo", Span::call_site())),
+                &[3, 0]
+            )
+            .to_string(),
+            quote! {
+                let abc = (foo, "123");
+            }
+            .to_string()
+        );
+
+        assert_eq!(
+            recurse_replace_tokens(
+                quote! {
+                    let abc = (hello, "123").iter_map(|_| xyz);
+                },
+                &TokenTree::Ident(Ident::new("foo", Span::call_site())),
+                &[6, 3]
+            )
+            .to_string(),
+            quote! {
+                let abc = (hello, "123").iter_map(|_| foo);
+            }
+            .to_string()
+        );
+    }
+}