debugger: Add extensions support (#30625)

Closes #ISSUE

Release Notes:

- N/A

---------

Co-authored-by: Anthony <anthony@zed.dev>

crates/extension_api/src/extension_api.rs

@@ -187,6 +187,16 @@ pub trait Extension: Send + Sync {
     ) -> Result<(), String> {
         Err("`index_docs` not implemented".to_string())
     }
+
+    /// Returns the debug adapter binary for the specified adapter name and configuration.
+    fn get_dap_binary(
+        &mut self,
+        _adapter_name: String,
+        _config: DebugTaskDefinition,
+        _user_provided_path: Option<String>,
+    ) -> Result<DebugAdapterBinary, String> {
+        Err("`get_dap_binary` not implemented".to_string())
+    }
 }
 
 /// Registers the provided type as a Zed extension.
@@ -371,6 +381,14 @@ impl wit::Guest for Component {
     ) -> Result<(), String> {
         extension().index_docs(provider, package, database)
     }
+
+    fn get_dap_binary(
+        adapter_name: String,
+        config: DebugTaskDefinition,
+        user_installed_path: Option<String>,
+    ) -> Result<DebugAdapterBinary, String> {
+        extension().get_dap_binary(adapter_name, config, user_installed_path)
+    }
 }
 
 /// The ID of a language server.

crates/extension_api/wit/since_v0.6.0/dap.wit

@@ -0,0 +1,56 @@
+interface dap {
+    use common.{env-vars};
+    record launch-request {
+        program: string,
+        cwd: option<string>,
+        args: list<string>,
+        envs: env-vars,
+    }
+
+    record attach-request {
+        process-id: option<u32>,
+    }
+
+    variant debug-request {
+        launch(launch-request),
+        attach(attach-request)
+    }
+
+    record tcp-arguments {
+        port: u16,
+        host: u32,
+        timeout: option<u64>,
+    }
+
+    record tcp-arguments-template {
+        port: option<u16>,
+        host: option<u32>,
+        timeout: option<u64>,
+    }
+    record debug-task-definition {
+        label: string,
+        adapter: string,
+        request: debug-request,
+        initialize-args: option<string>,
+        stop-on-entry: option<bool>,
+        tcp-connection: option<tcp-arguments-template>,
+    }
+
+    enum start-debugging-request-arguments-request {
+        launch,
+        attach,
+    }
+    record start-debugging-request-arguments {
+        configuration: string,
+        request: start-debugging-request-arguments-request,
+
+    }
+    record debug-adapter-binary {
+        command: string,
+        arguments: list<string>,
+        envs: env-vars,
+        cwd: option<string>,
+        connection: option<tcp-arguments>,
+        request-args: start-debugging-request-arguments
+    }
+}

crates/extension_api/wit/since_v0.6.0/extension.wit

@@ -2,6 +2,7 @@ package zed:extension;
 
 world extension {
     import context-server;
+    import dap;
     import github;
     import http-client;
     import platform;
@@ -10,6 +11,7 @@ world extension {
 
     use common.{env-vars, range};
     use context-server.{context-server-configuration};
+    use dap.{debug-adapter-binary, debug-task-definition};
     use lsp.{completion, symbol};
     use process.{command};
     use slash-command.{slash-command, slash-command-argument-completion, slash-command-output};
@@ -153,4 +155,7 @@ world extension {
 
     /// Indexes the docs for the specified package.
     export index-docs: func(provider-name: string, package-name: string, database: borrow<key-value-store>) -> result<_, string>;
+
+    /// Returns a configured debug adapter binary for a given debug task.
+    export get-dap-binary: func(adapter-name: string, config: debug-task-definition, user-installed-path: option<string>) -> result<debug-adapter-binary, string>;
 }