Implement a macro to help implement GstElements

Cargo.toml

@@ -9,6 +9,7 @@ use_cairo = ["cairo"]
 use_gdk4 = ["gdk4"]
 use_gio = ["gio", "gobject-macros/gio"]
 use_graphene = ["graphene"]
+use_gst = ["gst", "once_cell", "gobject-macros/use_gst"]
 use_gsk4 = ["gsk4"]
 use_gtk4 = ["gtk4", "gobject-macros/gtk4"]
 use_serde = ["serde", "gobject-macros/serde"]
@@ -23,8 +24,10 @@ glib = { git = "https://github.com/gtk-rs/gtk-rs-core", version = "0.16", featur
 graphene = { git = "https://github.com/gtk-rs/gtk-rs-core", version = "0.16", package = "graphene-rs", optional = true }
 gsk4 = { git = "https://github.com/gtk-rs/gtk4-rs", version = "0.5", optional = true }
 gtk4 = { git = "https://github.com/gtk-rs/gtk4-rs", version = "0.5", optional = true }
+gst = { git="https://gitlab.freedesktop.org/gstreamer/gstreamer-rs", package = "gstreamer", optional = true }
 gobject-macros = { path = "macros" }
 serde = { version = "1", features = ["derive"], optional = true }
+once_cell = { version = "1.0", optional = true }
 
 [dev-dependencies]
 futures-channel = "0.3"

README.md

@@ -10,6 +10,7 @@ mod obj {
         #[property(get, set)]
         my_prop: std::cell::Cell<u64>,
     }
+
     impl MyObj {
         #[signal]
         fn abc(&self) {}

core/Cargo.toml

@@ -6,10 +6,14 @@ edition = "2021"
 [lib]
 path = "lib.rs"
 
+[features]
+use_gst = ["gst"]
+
 [dependencies]
 bitflags = "1.3.2"
 darling = "0.13.1"
 heck = "0.4.0"
 proc-macro2 = "1.0.36"
 quote = "1.0.16"
 syn = { version = "1.0.89", features = ["full", "visit-mut"], default-features = false }
+gst = { git="https://gitlab.freedesktop.org/gstreamer/gstreamer-rs", package = "gstreamer", optional = true }

core/class.rs

@@ -11,9 +11,9 @@ use proc_macro2::{Span, TokenStream};
 use quote::{format_ident, quote, quote_spanned, ToTokens};
 use syn::{parse_quote, parse_quote_spanned, spanned::Spanned};
 
-#[derive(Debug, Default, FromMeta)]
+#[derive(Debug, Default, FromMeta, Clone)]
 #[darling(default)]
-struct Attrs {
+pub struct ClassAttrs {
     pub name: Option<syn::Ident>,
     pub ns: Option<syn::Ident>,
     pub class: Option<syn::Ident>,
@@ -32,7 +32,7 @@ struct Attrs {
     pub sync: Flag,
 }
 
-impl Attrs {
+impl ClassAttrs {
     fn validate(&self, errors: &Errors) {
         use crate::validations::*;
         let abstract_ = ("abstract", check_flag(&self.abstract_));
@@ -42,7 +42,7 @@ impl Attrs {
 }
 
 #[derive(Debug)]
-pub struct ClassOptions(Attrs);
+pub struct ClassOptions(pub ClassAttrs);
 
 impl ClassOptions {
     pub fn parse(tokens: TokenStream, errors: &Errors) -> Self {
@@ -380,7 +380,6 @@ impl ClassDefinition {
             quote_spanned! { Span::mixed_site() =>
                 let generated_prop_id = id as i64;
             }
-
         }
     }
     #[inline]

core/closures.rs

@@ -79,6 +79,7 @@ impl Capture {
         Some(match self {
             Self::Strong { ident, from, .. } => {
                 let target = format_ident!("____strong{}", index, span = Span::mixed_site());
+
                 let input = from
                     .as_ref()
                     .map(|f| f.to_token_stream())