Move script to nu engine (#3092)

* Move run_script to engine

* Add which dep and feature to engine

* Change unwrap to expect

* Add wasm specification

* Remove which from default, add specification correctly

* Add nu-platform-specifics

* Move is_external_cmd to platform_specifics

* Add is_external_cmd to host and use it instead of nu_platform directly

* Clean up if else logic in is_external_cmd

* Bump nu-platform-specifics version

* Pass context to print_err

* Commit cargo.lock

* Move print functions to own module inside nu-engine

* Hypocratic change to run windows-nightly again

* Add import for Ordering

* Move printing of error to host

* Move platform specific which functionality to basic host

* Allow no use of cmd_name

* Fix windows compile issue

crates/nu-command/src/commands/classified/external.rs

@@ -28,7 +28,7 @@ pub(crate) async fn run_external_command(
 ) -> Result<InputStream, ShellError> {
     trace!(target: "nu::run::external", "-> {}", command.name);
 
-    if !did_find_command(&command.name) {
+    if !context.host.lock().is_external_cmd(&command.name) {
         return Err(ShellError::labeled_error(
             "Command not found",
             "command not found",
@@ -443,35 +443,6 @@ fn spawn(
     }
 }
 
-pub fn did_find_command(#[allow(unused)] name: &str) -> bool {
-    #[cfg(not(feature = "which"))]
-    {
-        // we can't perform this check, so just assume it can be found
-        true
-    }
-
-    #[cfg(all(feature = "which", unix))]
-    {
-        which::which(name).is_ok()
-    }
-
-    #[cfg(all(feature = "which", windows))]
-    {
-        if which::which(name).is_ok() {
-            true
-        } else {
-            // Reference: https://ss64.com/nt/syntax-internal.html
-            let cmd_builtins = [
-                "assoc", "break", "color", "copy", "date", "del", "dir", "dpath", "echo", "erase",
-                "for", "ftype", "md", "mkdir", "mklink", "move", "path", "ren", "rename", "rd",
-                "rmdir", "start", "time", "title", "type", "ver", "verify", "vol",
-            ];
-
-            cmd_builtins.contains(&name)
-        }
-    }
-}
-
 fn expand_tilde<SI: ?Sized, P, HD>(input: &SI, home_dir: HD) -> std::borrow::Cow<str>
 where
     SI: AsRef<str>,

crates/nu-command/src/commands/command.rs

@@ -1,21 +0,0 @@
-use crate::prelude::*;
-use nu_engine::Command;
-use nu_errors::ShellError;
-use parking_lot::Mutex;
-use std::sync::atomic::AtomicBool;
-
-pub struct RunnableContext {
-    pub input: InputStream,
-    pub shell_manager: ShellManager,
-    pub host: Arc<parking_lot::Mutex<Box<dyn Host>>>,
-    pub ctrl_c: Arc<AtomicBool>,
-    pub current_errors: Arc<Mutex<Vec<ShellError>>>,
-    pub scope: Scope,
-    pub name: Tag,
-}
-
-impl RunnableContext {
-    pub fn get_command(&self, name: &str) -> Option<Command> {
-        self.scope.get_command(name)
-    }
-}

crates/nu-command/src/commands/run_external.rs

@@ -147,7 +147,7 @@ async fn maybe_autocd_dir<'a>(
         || (cmd.args.is_empty()
             && PathBuf::from(name).is_dir()
             && dunce::canonicalize(name).is_ok()
-            && !crate::commands::classified::external::did_find_command(&name))
+            && !ctx.host.lock().is_external_cmd(&name))
     {
         Some(name)
     } else {

crates/nu-command/src/commands/source.rs

@@ -1,5 +1,5 @@
 use crate::prelude::*;
-use nu_engine::WholeStreamCommand;
+use nu_engine::{script, WholeStreamCommand};
 
 use nu_errors::ShellError;
 use nu_parser::expand_path;
@@ -50,7 +50,7 @@ pub async fn source(args: CommandArgs) -> Result<OutputStream, ShellError> {
     let contents = std::fs::read_to_string(expand_path(&filename.item).into_owned());
     match contents {
         Ok(contents) => {
-            let result = crate::script::run_script_standalone(contents, true, &ctx, false).await;
+            let result = script::run_script_standalone(contents, true, &ctx, false).await;
 
             if let Err(err) = result {
                 ctx.error(err.into());

crates/nu-command/src/commands/table/command.rs

@@ -7,7 +7,9 @@ use nu_errors::ShellError;
 use nu_protocol::{Primitive, Signature, SyntaxShape, UntaggedValue, Value};
 use nu_table::{draw_table, Alignment, StyledString, TextStyle};
 use std::collections::HashMap;
+use std::sync::atomic::Ordering;
 use std::time::Instant;
+
 #[cfg(feature = "table-pager")]
 use {
     futures::future::join,