3 files changed, 81 insertions, 0 deletions
diff --git a/rust_macro/Cargo.lock b/rust_macro/Cargo.lock
new file mode 100644
index 0000000..6c3146f
--- /dev/null
+++ b/rust_macro/Cargo.lock
@@ -0,0 +1,46 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 3
+
+[[package]]
+name = "passwordmaker_macros"
+version = "1.0.0"
+dependencies = [
+ "quote",
+ "syn",
+]
+
+[[package]]
+name = "proc-macro2"
+version = "1.0.43"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0a2ca2c61bc9f3d74d2886294ab7b9853abd9c1ad903a3ac7815c58989bb7bab"
+dependencies = [
+ "unicode-ident",
+]
+
+[[package]]
+name = "quote"
+version = "1.0.21"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bbe448f377a7d6961e30f5955f9b8d106c3f5e449d493ee1b125c1d43c2b5179"
+dependencies = [
+ "proc-macro2",
+]
+
+[[package]]
+name = "syn"
+version = "1.0.99"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "58dbef6ec655055e20b86b15a8cc6d439cca19b667537ac6a1369572d151ab13"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "unicode-ident",
+]
+
+[[package]]
+name = "unicode-ident"
+version = "1.0.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "dcc811dc4066ac62f84f11307873c4850cb653bfa9b1719cee2bd2204a4bc5dd"
diff --git a/rust_macro/Cargo.toml b/rust_macro/Cargo.toml
new file mode 100644
index 0000000..93291e2
--- /dev/null
+++ b/rust_macro/Cargo.toml
@@ -0,0 +1,11 @@
+[package]
+name = "passwordmaker_macros"
+version = "1.0.0"
+
+[dependencies]
+syn = "1.0"
+quote = "1.0"
+
+[lib]
+name = "passwordmaker_macros"
+proc-macro = true
+\ No newline at end of file
diff --git a/rust_macro/src/lib.rs b/rust_macro/src/lib.rs
new file mode 100644
index 0000000..1d4a5ae
--- /dev/null
+++ b/rust_macro/src/lib.rs
@@ -0,0 +1,24 @@
+/// This is a dumping ground for all proc-macros used by passfish.
+/// There's a corresponding runtime module in the main crate.
+extern crate syn;
+extern crate quote;
+extern crate proc_macro;
+
+use proc_macro::TokenStream;
+use quote::quote;
+
+/// Adds a global constant name ENUMTYPE_
+/// Thanks, StackOverflow: https://stackoverflow.com/questions/41637978/how-to-get-the-number-of-elements-variants-in-an-enum-as-a-constant-value
+#[proc_macro_derive(EnumVariantCount)]
+pub fn derive_enum_variant_count(input: TokenStream) -> TokenStream {
+    let syn_item: syn::DeriveInput = syn::parse(input).unwrap();
+    let len = match syn_item.data {
+        syn::Data::Enum(enum_item) => enum_item.variants.len(),
+        _ => panic!("EnumVariantCount only works on Enums"),
+    };
+    let enum_name = syn_item.ident;
+    let result = quote! {
+        impl EnumVariantCount for #enum_name { fn variant_count() -> usize { #len } }
+    };
+    result.into()
+}