refactor: Migrate command summaries and delete legacy task paths

crates/turborepo-engine/src/builder.rs

@@ -210,19 +210,18 @@ impl<'a, L: TurboJsonLoader> EngineBuilder<'a, L> {
 
             // Collect tasks from each workspace and its extends chain
             for workspace in self.workspaces.iter() {
-                let implicit_tasks = if let Some(context) =
-                    self.package_graph.package_task_context(workspace)
-                    && let Some(toolchain_id) = context.toolchain()
-                    && let Some(toolchain) = self.package_graph.toolchains().get(toolchain_id)
-                {
-                    toolchain
-                        .registered_tasks(&context)
-                        .into_iter()
-                        .map(TaskName::from)
-                        .collect()
-                } else {
-                    HashSet::new()
-                };
+                let implicit_tasks =
+                    if let Some(context) = self.package_graph.package_task_context(workspace) {
+                        context
+                            .native_tasks()
+                            .tasks()
+                            .iter()
+                            .filter(|task| task.registered())
+                            .map(|task| TaskName::from(task.name().to_string()))
+                            .collect()
+                    } else {
+                        HashSet::new()
+                    };
                 let workspace_tasks = TaskInheritanceResolver::new(turbo_json_loader)
                     .with_implicit_tasks(implicit_tasks)
                     .resolve(workspace)?;

crates/turborepo-engine/src/builder/test.rs

@@ -143,35 +143,6 @@ impl Toolchain for AggregateToolchain {
         })
     }
 
-    fn task_command(
-        &self,
-        _context: &turborepo_repository::package_graph::PackageTaskContext<'_>,
-        _task: &str,
-        _pass_through_args: Option<&[String]>,
-        _override_command: Option<&[String]>,
-    ) -> Result<
-        Option<turborepo_repository::toolchain::TaskCommand>,
-        turborepo_repository::toolchain::Error,
-    > {
-        Ok(None)
-    }
-
-    fn task_display_command(
-        &self,
-        _context: &turborepo_repository::package_graph::PackageTaskContext<'_>,
-        _task: &str,
-    ) -> Option<String> {
-        None
-    }
-
-    fn defines_task(
-        &self,
-        _context: &turborepo_repository::package_graph::PackageTaskContext<'_>,
-        _task: &str,
-    ) -> bool {
-        false
-    }
-
     fn watch_spec(&self) -> turborepo_repository::toolchain::WatchSpec {
         turborepo_repository::toolchain::WatchSpec::default()
     }
@@ -241,35 +212,6 @@ impl Toolchain for StubIOToolchain {
         })
     }
 
-    fn task_command(
-        &self,
-        _context: &turborepo_repository::package_graph::PackageTaskContext<'_>,
-        _task: &str,
-        _pass_through_args: Option<&[String]>,
-        _override_command: Option<&[String]>,
-    ) -> Result<
-        Option<turborepo_repository::toolchain::TaskCommand>,
-        turborepo_repository::toolchain::Error,
-    > {
-        Ok(None)
-    }
-
-    fn task_display_command(
-        &self,
-        _context: &turborepo_repository::package_graph::PackageTaskContext<'_>,
-        _task: &str,
-    ) -> Option<String> {
-        None
-    }
-
-    fn defines_task(
-        &self,
-        _package: &turborepo_repository::package_graph::PackageTaskContext<'_>,
-        task: &str,
-    ) -> bool {
-        matches!(task, "build" | "test")
-    }
-
     fn watch_spec(&self) -> turborepo_repository::toolchain::WatchSpec {
         turborepo_repository::toolchain::WatchSpec::default()
     }
@@ -286,10 +228,10 @@ impl Toolchain for StubIOToolchain {
 
     fn derives_task_io(
         &self,
-        package: &turborepo_repository::package_graph::PackageTaskContext<'_>,
-        task: &str,
+        _package: &turborepo_repository::package_graph::PackageTaskContext<'_>,
+        _task: &str,
     ) -> bool {
-        self.defines_task(package, task)
+        true
     }
 
     fn task_io_env_vars(&self) -> &[&str] {

crates/turborepo-lib/src/run/builder.rs

@@ -1554,35 +1554,6 @@ mod task_io_context_tests {
             Box::pin(async { Ok(DiscoveredPackages::default()) })
         }
 
-        fn task_command(
-            &self,
-            _context: &turborepo_repository::package_graph::PackageTaskContext<'_>,
-            _task: &str,
-            _pass_through_args: Option<&[String]>,
-            _override_command: Option<&[String]>,
-        ) -> Result<
-            Option<turborepo_repository::toolchain::TaskCommand>,
-            turborepo_repository::toolchain::Error,
-        > {
-            Ok(None)
-        }
-
-        fn task_display_command(
-            &self,
-            _context: &turborepo_repository::package_graph::PackageTaskContext<'_>,
-            _task: &str,
-        ) -> Option<String> {
-            None
-        }
-
-        fn defines_task(
-            &self,
-            _context: &turborepo_repository::package_graph::PackageTaskContext<'_>,
-            _task: &str,
-        ) -> bool {
-            false
-        }
-
         fn watch_spec(&self) -> turborepo_repository::toolchain::WatchSpec {
             turborepo_repository::toolchain::WatchSpec::default()
         }

crates/turborepo-lib/src/run/task_access.rs

@@ -70,19 +70,23 @@ fn task_access_trace_enabled(repo_root: &AbsoluteSystemPathBuf) -> Result<bool,
         return Ok(false);
     }
 
-    // read package.json at root
+    // read package.json at root through the same observation vocabulary as
+    // the native-task catalog — do not read scripts for task identity directly.
     let package_json_path = repo_root.join_components(&["package.json"]);
     let package_json_content = fs::read_to_string(package_json_path)?;
     let package: PackageJson = serde_json::from_str(&package_json_content)?;
-
-    if let Some(scripts) = package.scripts {
-        return match scripts.get("build") {
-            Some(script) => Ok(script == "next build"),
-            _ => Ok(false),
-        };
-    }
-
-    Ok(false)
+    let scripts = package.scripts.unwrap_or_default();
+    let scripts: std::collections::BTreeMap<_, _> = scripts
+        .into_iter()
+        .map(|(name, value)| (name, turborepo_errors::Spanned::new(value)))
+        .collect();
+    let observation = turborepo_repository::native_tasks::observation_from_scripts("//", &scripts);
+    Ok(observation.tasks.iter().any(|task| {
+        task.name() == "build"
+            && task
+                .script()
+                .is_some_and(|script| script.as_inner() == "next build")
+    }))
 }
 
 impl TaskAccessTraceFile {