Drop requirements for resource handler impls

Do not require that these impls be send, sync or debug.

pulldown-cmark-mdcat/src/resources.rs

@@ -46,7 +46,7 @@ impl MimeData {
 ///
 /// For remote URLs, see e.g. [mdcat-http-reqwest](https://docs.rs/mdcat-http-reqwest)
 /// for an implementation which fetches HTTP resources with the `reqwest` library.
-pub trait ResourceUrlHandler: Send + Sync + Debug {
+pub trait ResourceUrlHandler {
     /// Read a resource.
     ///
     /// Read data from the given `url`, and return the data and its associated mime type if known,
@@ -80,7 +80,6 @@ pub fn filter_schemes<'a>(schemes: &[&str], url: &'a Url) -> Result<&'a Url> {
 }
 
 /// A resource handler which dispatches reading among a list of inner handlers.
-#[derive(Debug)]
 pub struct DispatchingResourceHandler {
     /// Inner handlers.
     handlers: Vec<Box<dyn ResourceUrlHandler>>,

pulldown-cmark-mdcat/src/terminal/capabilities/iterm2.rs

@@ -40,7 +40,7 @@ impl ITerm2Protocol {
 /// supported by macOS, this may yield false positives, i.e. this implementation might not return
 /// an error even though iTerm2 cannot actually display the image.
 impl InlineImageProtocol for ITerm2Protocol {
-    #[instrument(skip(self, writer, _terminal_size), fields(url = %url))]
+    #[instrument(skip(self, writer, _terminal_size, resource_handler), fields(url = %url))]
     fn write_inline_image(
         &self,
         writer: &mut dyn Write,

pulldown-cmark-mdcat/src/terminal/capabilities/kitty.rs

@@ -307,7 +307,7 @@ impl KittyGraphicsProtocol {
 /// See <https://sw.kovidgoyal.net/kitty/graphics-protocol.html#control-data-reference>
 /// for reference.
 impl InlineImageProtocol for KittyGraphicsProtocol {
-    #[instrument(skip(self, writer, terminal_size))]
+    #[instrument(skip(self, writer, resource_handler, terminal_size))]
     fn write_inline_image(
         &self,
         writer: &mut dyn Write,

pulldown-cmark-mdcat/tests/render.rs

@@ -33,22 +33,18 @@ fn syntax_set() -> &'static SyntaxSet {
     SYNTAX_SET.get_or_init(SyntaxSet::load_defaults_newlines)
 }
 
-static RESOURCE_HANDLER: OnceLock<DispatchingResourceHandler> = OnceLock::new();
-
-fn resource_handler() -> &'static DispatchingResourceHandler {
-    RESOURCE_HANDLER.get_or_init(|| {
-        let handlers: Vec<Box<dyn ResourceUrlHandler>> = vec![
-            Box::new(FileResourceHandler::new(TEST_READ_LIMIT)),
-            Box::new(
-                HttpResourceHandler::with_user_agent(
-                    TEST_READ_LIMIT,
-                    concat!(env!("CARGO_PKG_NAME"), "/", env!("CARGO_PKG_VERSION")),
-                )
-                .unwrap(),
-            ),
-        ];
-        DispatchingResourceHandler::new(handlers)
-    })
+fn resource_handler() -> DispatchingResourceHandler {
+    let handlers: Vec<Box<dyn ResourceUrlHandler>> = vec![
+        Box::new(FileResourceHandler::new(TEST_READ_LIMIT)),
+        Box::new(
+            HttpResourceHandler::with_user_agent(
+                TEST_READ_LIMIT,
+                concat!(env!("CARGO_PKG_NAME"), "/", env!("CARGO_PKG_VERSION")),
+            )
+            .unwrap(),
+        ),
+    ];
+    DispatchingResourceHandler::new(handlers)
 }
 
 fn render_to_string<P: AsRef<Path>>(markdown_file: P, settings: &Settings) -> String {
@@ -66,7 +62,7 @@ fn render_to_string<P: AsRef<Path>>(markdown_file: P, settings: &Settings) -> St
         hostname: "HOSTNAME".to_string(),
         ..Environment::for_local_directory(&base_dir).unwrap()
     };
-    pulldown_cmark_mdcat::push_tty(settings, &env, resource_handler(), &mut sink, parser).unwrap();
+    pulldown_cmark_mdcat::push_tty(settings, &env, &resource_handler(), &mut sink, parser).unwrap();
     String::from_utf8(sink).unwrap()
 }