Refactor scope commands (#10023)

crates/nu-cmd-lang/src/core_commands/scope/aliases.rs

@@ -35,7 +35,7 @@ impl Command for ScopeAliases {
         let ctrlc = engine_state.ctrlc.clone();
 
         let mut scope_data = ScopeData::new(engine_state, stack);
-        scope_data.populate_all();
+        scope_data.populate_decls();
 
         Ok(scope_data.collect_aliases(span).into_pipeline_data(ctrlc))
     }

crates/nu-cmd-lang/src/core_commands/scope/commands.rs

@@ -35,7 +35,7 @@ impl Command for ScopeCommands {
         let ctrlc = engine_state.ctrlc.clone();
 
         let mut scope_data = ScopeData::new(engine_state, stack);
-        scope_data.populate_all();
+        scope_data.populate_decls();
 
         Ok(scope_data.collect_commands(span).into_pipeline_data(ctrlc))
     }

crates/nu-cmd-lang/src/core_commands/scope/engine_stats.rs

@@ -31,8 +31,7 @@ impl Command for ScopeEngineStats {
     ) -> Result<PipelineData, ShellError> {
         let span = call.head;
 
-        let mut scope_data = ScopeData::new(engine_state, stack);
-        scope_data.populate_all();
+        let scope_data = ScopeData::new(engine_state, stack);
 
         Ok(scope_data.collect_engine_state(span).into_pipeline_data())
     }

crates/nu-cmd-lang/src/core_commands/scope/externs.rs

@@ -0,0 +1,62 @@
+use nu_engine::scope::ScopeData;
+use nu_protocol::ast::Call;
+use nu_protocol::engine::{Command, EngineState, Stack};
+use nu_protocol::{
+    Category, Example, IntoInterruptiblePipelineData, PipelineData, ShellError, Signature, Type,
+};
+
+#[derive(Clone)]
+pub struct ScopeExterns;
+
+impl Command for ScopeExterns {
+    fn name(&self) -> &str {
+        "scope externs"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("scope externs")
+            .input_output_types(vec![(Type::Nothing, Type::Any)])
+            .allow_variants_without_examples(true)
+            .category(Category::Filters)
+    }
+
+    fn usage(&self) -> &str {
+        "Output info on the known externals in the current scope."
+    }
+
+    fn run(
+        &self,
+        engine_state: &EngineState,
+        stack: &mut Stack,
+        call: &Call,
+        _input: PipelineData,
+    ) -> Result<PipelineData, ShellError> {
+        let span = call.head;
+        let ctrlc = engine_state.ctrlc.clone();
+
+        let mut scope_data = ScopeData::new(engine_state, stack);
+        scope_data.populate_decls();
+
+        Ok(scope_data.collect_externs(span).into_pipeline_data(ctrlc))
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![Example {
+            description: "Show the known externals in the current scope",
+            example: "scope externs",
+            result: None,
+        }]
+    }
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+
+    #[test]
+    fn test_examples() {
+        use crate::test_examples;
+
+        test_examples(ScopeExterns {})
+    }
+}

crates/nu-cmd-lang/src/core_commands/scope/mod.rs

@@ -2,6 +2,7 @@ mod aliases;
 mod command;
 mod commands;
 mod engine_stats;
+mod externs;
 mod modules;
 mod variables;
 
@@ -9,5 +10,6 @@ pub use aliases::*;
 pub use command::*;
 pub use commands::*;
 pub use engine_stats::*;
+pub use externs::*;
 pub use modules::*;
 pub use variables::*;

crates/nu-cmd-lang/src/core_commands/scope/variables.rs

@@ -35,7 +35,7 @@ impl Command for ScopeVariables {
         let ctrlc = engine_state.ctrlc.clone();
 
         let mut scope_data = ScopeData::new(engine_state, stack);
-        scope_data.populate_all();
+        scope_data.populate_vars();
 
         Ok(scope_data.collect_vars(span).into_pipeline_data(ctrlc))
     }

crates/nu-cmd-lang/src/default_context.rs

@@ -58,6 +58,7 @@ pub fn create_default_context() -> EngineState {
             ScopeAliases,
             ScopeCommands,
             ScopeEngineStats,
+            ScopeExterns,
             ScopeModules,
             ScopeVariables,
             Try,

crates/nu-command/src/help/help_aliases.rs

@@ -169,7 +169,7 @@ pub fn help_aliases(
 
 fn build_help_aliases(engine_state: &EngineState, stack: &Stack, span: Span) -> Vec<Value> {
     let mut scope_data = ScopeData::new(engine_state, stack);
-    scope_data.populate_all();
+    scope_data.populate_decls();
 
     scope_data.collect_aliases(span)
 }

crates/nu-command/src/help/help_externs.rs

@@ -144,7 +144,7 @@ pub fn help_externs(
 
 fn build_help_externs(engine_state: &EngineState, stack: &Stack, span: Span) -> Vec<Value> {
     let mut scope = ScopeData::new(engine_state, stack);
-    scope.populate_all();
+    scope.populate_decls();
     scope.collect_externs(span)
 }
 

crates/nu-command/tests/commands/help.rs

@@ -2,6 +2,8 @@ use nu_test_support::fs::Stub::FileWithContent;
 use nu_test_support::playground::Playground;
 use nu_test_support::{nu, nu_repl_code, pipeline};
 
+// Note: These tests might slightly overlap with tests/scope/mod.rs
+
 #[test]
 fn help_commands_length() {
     let actual = nu!("help commands | length");
@@ -22,7 +24,6 @@ fn help_shows_signature() {
     assert!(!actual.out.contains("Input/output types"));
 }
 
-#[ignore = "TODO: Need to decide how to do help messages of new aliases"]
 #[test]
 fn help_aliases() {
     let code = &[
@@ -34,7 +35,6 @@ fn help_aliases() {
     assert_eq!(actual.out, "1");
 }
 
-#[ignore = "TODO: Need to decide how to do help messages of new aliases"]
 #[test]
 fn help_alias_usage_1() {
     Playground::setup("help_alias_usage_1", |dirs, sandbox| {
@@ -56,7 +56,6 @@ fn help_alias_usage_1() {
     })
 }
 
-#[ignore = "TODO: Need to decide how to do help messages of new aliases"]
 #[test]
 fn help_alias_usage_2() {
     let code = &[
@@ -68,7 +67,6 @@ fn help_alias_usage_2() {
     assert_eq!(actual.out, "line2");
 }
 
-#[ignore = "TODO: Need to decide how to do help messages of new aliases"]
 #[test]
 fn help_alias_usage_3() {
     Playground::setup("help_alias_usage_3", |dirs, sandbox| {
@@ -91,7 +89,6 @@ fn help_alias_usage_3() {
     })
 }
 
-#[ignore = "TODO: Need to decide how to do help messages of new aliases"]
 #[test]
 fn help_alias_name() {
     Playground::setup("help_alias_name", |dirs, sandbox| {
@@ -113,7 +110,6 @@ fn help_alias_name() {
     })
 }
 
-#[ignore = "TODO: Need to decide how to do help messages of new aliases"]
 #[test]
 fn help_alias_name_f() {
     Playground::setup("help_alias_name_f", |dirs, sandbox| {
@@ -133,7 +129,6 @@ fn help_alias_name_f() {
     })
 }
 
-#[ignore = "TODO: Need to decide how to do help messages of new aliases"]
 #[test]
 fn help_export_alias_name_single_word() {
     Playground::setup("help_export_alias_name_single_word", |dirs, sandbox| {
@@ -155,7 +150,6 @@ fn help_export_alias_name_single_word() {
     })
 }
 
-#[ignore = "TODO: Need to decide how to do help messages of new aliases"]
 #[test]
 fn help_export_alias_name_multi_word() {
     Playground::setup("help_export_alias_name_multi_word", |dirs, sandbox| {
@@ -302,7 +296,6 @@ fn help_usage_extra_usage_command() {
     })
 }
 
-#[ignore = "TODO: Need to decide how to do help messages of new aliases"]
 #[test]
 fn help_usage_extra_usage_alias() {
     Playground::setup("help_usage_extra_usage_alias", |dirs, sandbox| {
@@ -360,7 +353,7 @@ fn help_modules_main_2() {
         r#"module spam {
             export def main [] { 'foo' };
         }"#,
-        "help modules | where name == spam | get 0.commands.0",
+        "help modules | where name == spam | get 0.commands.0.name",
     ];
 
     let actual = nu!(pipeline(&inp.join("; ")));
@@ -368,19 +361,6 @@ fn help_modules_main_2() {
     assert_eq!(actual.out, "spam");
 }
 
-#[ignore = "TODO: Can't have alias with the same name as command"]
-#[test]
-fn help_alias_before_command() {
-    let code = &[
-        "alias SPAM = echo 'spam'",
-        "def SPAM [] { 'spam' }",
-        "help SPAM",
-    ];
-    let actual = nu!(nu_repl_code(code));
-
-    assert!(actual.out.contains("Alias"));
-}
-
 #[test]
 fn nothing_type_annotation() {
     let actual = nu!(pipeline(

crates/nu-engine/src/scope.rs

@@ -1,53 +1,10 @@
 use nu_protocol::{
     engine::{Command, EngineState, Stack, Visibility},
-    ShellError, Signature, Span, SyntaxShape, Type, Value,
+    ModuleId, Signature, Span, SyntaxShape, Type, Value,
 };
-use std::borrow::Borrow;
 use std::cmp::Ordering;
 use std::collections::HashMap;
 
-pub fn create_scope(
-    engine_state: &EngineState,
-    stack: &Stack,
-    span: Span,
-) -> Result<Value, ShellError> {
-    let mut scope_data = ScopeData::new(engine_state, stack);
-
-    scope_data.populate_all();
-
-    let mut cols = vec![];
-    let mut vals = vec![];
-
-    cols.push("vars".to_string());
-    vals.push(Value::List {
-        vals: scope_data.collect_vars(span),
-        span,
-    });
-
-    cols.push("commands".to_string());
-    vals.push(Value::List {
-        vals: scope_data.collect_commands(span),
-        span,
-    });
-
-    cols.push("aliases".to_string());
-    vals.push(Value::List {
-        vals: scope_data.collect_aliases(span),
-        span,
-    });
-
-    cols.push("modules".to_string());
-    vals.push(Value::List {
-        vals: scope_data.collect_modules(span),
-        span,
-    });
-
-    cols.push("engine_state".to_string());
-    vals.push(scope_data.collect_engine_state(span));
-
-    Ok(Value::Record { cols, vals, span })
-}
-
 pub struct ScopeData<'e, 's> {
     engine_state: &'e EngineState,
     stack: &'s Stack,
@@ -69,11 +26,16 @@ impl<'e, 's> ScopeData<'e, 's> {
         }
     }
 
-    pub fn populate_all(&mut self) {
+    pub fn populate_vars(&mut self) {
         for overlay_frame in self.engine_state.active_overlays(&[]) {
             self.vars_map.extend(&overlay_frame.vars);
+        }
+    }
+
+    // decls include all commands, i.e., normal commands, aliases, and externals
+    pub fn populate_decls(&mut self) {
+        for overlay_frame in self.engine_state.active_overlays(&[]) {
             self.decls_map.extend(&overlay_frame.decls);
-            self.modules_map.extend(&overlay_frame.modules);
             self.visibility.merge_with(overlay_frame.visibility.clone());
         }
     }
@@ -86,20 +48,28 @@ impl<'e, 's> ScopeData<'e, 's> {
 
     pub fn collect_vars(&self, span: Span) -> Vec<Value> {
         let mut vars = vec![];
-        for var in &self.vars_map {
-            let var_name = Value::string(String::from_utf8_lossy(var.0).to_string(), span);
 
-            let var_type = Value::string(self.engine_state.get_var(**var.1).ty.to_string(), span);
+        for (var_name, var_id) in &self.vars_map {
+            let var_name = Value::string(String::from_utf8_lossy(var_name).to_string(), span);
 
-            let var_value = if let Ok(val) = self.stack.get_var(**var.1, span) {
+            let var_type = Value::string(self.engine_state.get_var(**var_id).ty.to_string(), span);
+
+            let var_value = if let Ok(val) = self.stack.get_var(**var_id, span) {
                 val
             } else {
                 Value::nothing(span)
             };
 
+            let var_id_val = Value::int(**var_id as i64, span);
+
             vars.push(Value::Record {
-                cols: vec!["name".to_string(), "type".to_string(), "value".to_string()],
-                vals: vec![var_name, var_type, var_value],
+                cols: vec![
+                    "name".to_string(),
+                    "type".to_string(),
+                    "value".to_string(),
+                    "var_id".to_string(),
+                ],
+                vals: vec![var_name, var_type, var_value, var_id_val],
                 span,
             })
         }
@@ -108,6 +78,7 @@ impl<'e, 's> ScopeData<'e, 's> {
 
     pub fn collect_commands(&self, span: Span) -> Vec<Value> {
         let mut commands = vec![];
+
         for (command_name, decl_id) in &self.decls_map {
             if self.visibility.is_decl_id_visible(decl_id)
                 && !self.engine_state.get_decl(**decl_id).is_alias()
@@ -115,27 +86,12 @@ impl<'e, 's> ScopeData<'e, 's> {
                 let mut cols = vec![];
                 let mut vals = vec![];
 
-                let mut module_commands = vec![];
-                for module in &self.modules_map {
-                    let module_name = String::from_utf8_lossy(module.0).to_string();
-                    let module_id = self.engine_state.find_module(module.0, &[]);
-                    if let Some(module_id) = module_id {
-                        let module = self.engine_state.get_module(module_id);
-                        if module.has_decl(command_name) {
-                            module_commands.push(module_name);
-                        }
-                    }
-                }
-
                 cols.push("name".into());
                 vals.push(Value::String {
                     val: String::from_utf8_lossy(command_name).to_string(),
                     span,
                 });
 
-                cols.push("module_name".into());
-                vals.push(Value::string(module_commands.join(", "), span));
-
                 let decl = self.engine_state.get_decl(**decl_id);
                 let signature = decl.signature();
 
@@ -238,6 +194,9 @@ impl<'e, 's> ScopeData<'e, 's> {
                     span,
                 });
 
+                cols.push("decl_id".into());
+                vals.push(Value::int(**decl_id as i64, span));
+
                 commands.push(Value::Record { cols, vals, span })
             }
         }
@@ -488,6 +447,7 @@ impl<'e, 's> ScopeData<'e, 's> {
 
     pub fn collect_externs(&self, span: Span) -> Vec<Value> {
         let mut externals = vec![];
+
         for (command_name, decl_id) in &self.decls_map {
             let decl = self.engine_state.get_decl(**decl_id);
 
@@ -495,36 +455,21 @@ impl<'e, 's> ScopeData<'e, 's> {
                 let mut cols = vec![];
                 let mut vals = vec![];
 
-                let mut module_commands = vec![];
-                for module in &self.modules_map {
-                    let module_name = String::from_utf8_lossy(module.0).to_string();
-                    let module_id = self.engine_state.find_module(module.0, &[]);
-                    if let Some(module_id) = module_id {
-                        let module = self.engine_state.get_module(module_id);
-                        if module.has_decl(command_name) {
-                            module_commands.push(module_name);
-                        }
-                    }
-                }
-
                 cols.push("name".into());
                 vals.push(Value::String {
                     val: String::from_utf8_lossy(command_name).to_string(),
                     span,
                 });
 
-                cols.push("module_name".into());
-                vals.push(Value::String {
-                    val: module_commands.join(", "),
-                    span,
-                });
-
                 cols.push("usage".to_string());
                 vals.push(Value::String {
                     val: decl.usage().into(),
                     span,
                 });
 
+                cols.push("decl_id".into());
+                vals.push(Value::int(**decl_id as i64, span));
+
                 externals.push(Value::Record { cols, vals, span })
             }
         }
@@ -534,17 +479,23 @@ impl<'e, 's> ScopeData<'e, 's> {
 
     pub fn collect_aliases(&self, span: Span) -> Vec<Value> {
         let mut aliases = vec![];
-        for (_, decl_id) in self.engine_state.get_decls_sorted(false) {
+
+        for (decl_name, decl_id) in self.engine_state.get_decls_sorted(false) {
             if self.visibility.is_decl_id_visible(&decl_id) {
                 let decl = self.engine_state.get_decl(decl_id);
                 if let Some(alias) = decl.as_alias() {
-                    let sig = decl.signature().update_from_command(decl.borrow());
-                    let key = sig.name;
-
                     aliases.push(Value::Record {
-                        cols: vec!["name".into(), "expansion".into(), "usage".into()],
+                        cols: vec![
+                            "name".into(),
+                            "expansion".into(),
+                            "usage".into(),
+                            "decl_id".into(),
+                        ],
                         vals: vec![
-                            Value::String { val: key, span },
+                            Value::String {
+                                val: String::from_utf8_lossy(&decl_name).to_string(),
+                                span,
+                            },
                             Value::String {
                                 val: String::from_utf8_lossy(
                                     self.engine_state.get_span_contents(alias.wrapped_call.span),
@@ -553,7 +504,11 @@ impl<'e, 's> ScopeData<'e, 's> {
                                 span,
                             },
                             Value::String {
-                                val: alias.signature().usage,
+                                val: alias.usage().to_string(),
+                                span,
+                            },
+                            Value::Int {
+                                val: decl_id as i64,
                                 span,
                             },
                         ],
@@ -567,70 +522,156 @@ impl<'e, 's> ScopeData<'e, 's> {
         aliases
     }
 
+    fn collect_module(&self, module_name: &[u8], module_id: &ModuleId, span: Span) -> Value {
+        let module = self.engine_state.get_module(*module_id);
+
+        let all_decls = module.decls();
+
+        let export_commands: Vec<Value> = all_decls
+            .iter()
+            .filter_map(|(name_bytes, decl_id)| {
+                let decl = self.engine_state.get_decl(*decl_id);
+
+                if !decl.is_alias() && !decl.is_known_external() {
+                    Some(Value::record(
+                        vec!["name".into(), "decl_id".into()],
+                        vec![
+                            Value::string(String::from_utf8_lossy(name_bytes), span),
+                            Value::int(*decl_id as i64, span),
+                        ],
+                        span,
+                    ))
+                } else {
+                    None
+                }
+            })
+            .collect();
+
+        let export_aliases: Vec<Value> = all_decls
+            .iter()
+            .filter_map(|(name_bytes, decl_id)| {
+                let decl = self.engine_state.get_decl(*decl_id);
+
+                if decl.is_alias() {
+                    Some(Value::record(
+                        vec!["name".into(), "decl_id".into()],
+                        vec![
+                            Value::string(String::from_utf8_lossy(name_bytes), span),
+                            Value::int(*decl_id as i64, span),
+                        ],
+                        span,
+                    ))
+                } else {
+                    None
+                }
+            })
+            .collect();
+
+        let export_externs: Vec<Value> = all_decls
+            .iter()
+            .filter_map(|(name_bytes, decl_id)| {
+                let decl = self.engine_state.get_decl(*decl_id);
+
+                if decl.is_known_external() {
+                    Some(Value::record(
+                        vec!["name".into(), "decl_id".into()],
+                        vec![
+                            Value::string(String::from_utf8_lossy(name_bytes), span),
+                            Value::int(*decl_id as i64, span),
+                        ],
+                        span,
+                    ))
+                } else {
+                    None
+                }
+            })
+            .collect();
+
+        let export_submodules: Vec<Value> = module
+            .submodules()
+            .iter()
+            .map(|(name_bytes, submodule_id)| self.collect_module(name_bytes, submodule_id, span))
+            .collect();
+
+        let export_consts: Vec<Value> = module
+            .vars()
+            .iter()
+            .map(|(name_bytes, var_id)| {
+                Value::record(
+                    vec!["name".into(), "type".into(), "var_id".into()],
+                    vec![
+                        Value::string(String::from_utf8_lossy(name_bytes), span),
+                        Value::string(self.engine_state.get_var(*var_id).ty.to_string(), span),
+                        Value::int(*var_id as i64, span),
+                    ],
+                    span,
+                )
+            })
+            .collect();
+
+        let export_env_block = module.env_block.map_or_else(
+            || Value::nothing(span),
+            |block_id| Value::Block {
+                val: block_id,
+                span,
+            },
+        );
+
+        let module_usage = self
+            .engine_state
+            .build_module_usage(*module_id)
+            .map(|(usage, _)| usage)
+            .unwrap_or_default();
+
+        Value::Record {
+            cols: vec![
+                "name".into(),
+                "commands".into(),
+                "aliases".into(),
+                "externs".into(),
+                "submodules".into(),
+                "constants".into(),
+                "env_block".into(),
+                "usage".into(),
+                "module_id".into(),
+            ],
+            vals: vec![
+                Value::string(String::from_utf8_lossy(module_name), span),
+                Value::List {
+                    vals: export_commands,
+                    span,
+                },
+                Value::List {
+                    vals: export_aliases,
+                    span,
+                },
+                Value::List {
+                    vals: export_externs,
+                    span,
+                },
+                Value::List {
+                    vals: export_submodules,
+                    span,
+                },
+                Value::List {
+                    vals: export_consts,
+                    span,
+                },
+                export_env_block,
+                Value::string(module_usage, span),
+                Value::int(*module_id as i64, span),
+            ],
+            span,
+        }
+    }
+
     pub fn collect_modules(&self, span: Span) -> Vec<Value> {
         let mut modules = vec![];
 
         for (module_name, module_id) in &self.modules_map {
-            let module = self.engine_state.get_module(**module_id);
-
-            let export_commands: Vec<Value> = module
-                .decls()
-                .iter()
-                .filter(|(_, id)| {
-                    self.visibility.is_decl_id_visible(id)
-                        && !self.engine_state.get_decl(*id).is_alias()
-                })
-                .map(|(bytes, _)| Value::string(String::from_utf8_lossy(bytes), span))
-                .collect();
-
-            let export_aliases: Vec<Value> = module
-                .decls()
-                .iter()
-                .filter(|(_, id)| {
-                    self.visibility.is_decl_id_visible(id)
-                        && self.engine_state.get_decl(*id).is_alias()
-                })
-                .map(|(bytes, _)| Value::string(String::from_utf8_lossy(bytes), span))
-                .collect();
-
-            let export_env_block = module.env_block.map_or_else(
-                || Value::nothing(span),
-                |block_id| Value::Block {
-                    val: block_id,
-                    span,
-                },
-            );
-
-            let module_usage = self
-                .engine_state
-                .build_module_usage(**module_id)
-                .map(|(usage, _)| usage)
-                .unwrap_or_default();
-
-            modules.push(Value::Record {
-                cols: vec![
-                    "name".into(),
-                    "commands".into(),
-                    "aliases".into(),
-                    "env_block".into(),
-                    "usage".into(),
-                ],
-                vals: vec![
-                    Value::string(String::from_utf8_lossy(module_name), span),
-                    Value::List {
-                        vals: export_commands,
-                        span,
-                    },
-                    Value::List {
-                        vals: export_aliases,
-                        span,
-                    },
-                    export_env_block,
-                    Value::string(module_usage, span),
-                ],
-                span,
-            });
+            modules.push(self.collect_module(module_name, module_id, span));
         }
+
         modules.sort_by(|a, b| a.partial_cmp(b).unwrap_or(Ordering::Equal));
         modules
     }
@@ -660,6 +701,7 @@ impl<'e, 's> ScopeData<'e, 's> {
                 span,
             ),
         ];
+
         Value::Record {
             cols: engine_state_cols,
             vals: engine_state_vals,

crates/nu-parser/src/parse_keywords.rs

@@ -749,6 +749,7 @@ pub fn parse_alias(
 
     if let Some(decl_id) = working_set.find_decl(b"alias") {
         let (command_spans, rest_spans) = spans.split_at(split_id);
+        let (usage, extra_usage) = working_set.build_usage(&lite_command.comments);
 
         let original_starting_error_count = working_set.parse_errors.len();
 
@@ -906,6 +907,8 @@ pub fn parse_alias(
                 name: alias_name,
                 command,
                 wrapped_call,
+                usage,
+                extra_usage,
             };
 
             working_set.add_decl(Box::new(decl));

crates/nu-protocol/src/alias.rs

@@ -3,15 +3,16 @@ use crate::PipelineData;
 use crate::{
     ast::{Call, Expression},
     engine::Command,
-    BlockId, Example, ShellError, Signature,
+    ShellError, Signature,
 };
-use std::path::PathBuf;
 
 #[derive(Clone)]
 pub struct Alias {
     pub name: String,
     pub command: Option<Box<dyn Command>>, // None if external call
     pub wrapped_call: Expression,
+    pub usage: String,
+    pub extra_usage: String,
 }
 
 impl Command for Alias {
@@ -28,19 +29,11 @@ impl Command for Alias {
     }
 
     fn usage(&self) -> &str {
-        if let Some(cmd) = &self.command {
-            cmd.usage()
-        } else {
-            "This alias wraps an unknown external command."
-        }
+        &self.usage
     }
 
     fn extra_usage(&self) -> &str {
-        if let Some(cmd) = &self.command {
-            cmd.extra_usage()
-        } else {
-            ""
-        }
+        &self.extra_usage
     }
 
     fn run(
@@ -57,30 +50,6 @@ impl Command for Alias {
         })
     }
 
-    fn examples(&self) -> Vec<Example> {
-        if let Some(cmd) = &self.command {
-            cmd.examples()
-        } else {
-            vec![]
-        }
-    }
-
-    fn is_builtin(&self) -> bool {
-        if let Some(cmd) = &self.command {
-            cmd.is_builtin()
-        } else {
-            false
-        }
-    }
-
-    fn is_known_external(&self) -> bool {
-        if let Some(cmd) = &self.command {
-            cmd.is_known_external()
-        } else {
-            false
-        }
-    }
-
     fn is_alias(&self) -> bool {
         true
     }
@@ -88,54 +57,4 @@ impl Command for Alias {
     fn as_alias(&self) -> Option<&Alias> {
         Some(self)
     }
-
-    fn is_custom_command(&self) -> bool {
-        if let Some(cmd) = &self.command {
-            cmd.is_custom_command()
-        } else if self.get_block_id().is_some() {
-            true
-        } else {
-            self.is_known_external()
-        }
-    }
-
-    fn is_sub(&self) -> bool {
-        if let Some(cmd) = &self.command {
-            cmd.is_sub()
-        } else {
-            self.name().contains(' ')
-        }
-    }
-
-    fn is_parser_keyword(&self) -> bool {
-        if let Some(cmd) = &self.command {
-            cmd.is_parser_keyword()
-        } else {
-            false
-        }
-    }
-
-    fn is_plugin(&self) -> Option<(&PathBuf, &Option<PathBuf>)> {
-        if let Some(cmd) = &self.command {
-            cmd.is_plugin()
-        } else {
-            None
-        }
-    }
-
-    fn get_block_id(&self) -> Option<BlockId> {
-        if let Some(cmd) = &self.command {
-            cmd.get_block_id()
-        } else {
-            None
-        }
-    }
-
-    fn search_terms(&self) -> Vec<&str> {
-        if let Some(cmd) = &self.command {
-            cmd.search_terms()
-        } else {
-            vec![]
-        }
-    }
 }

tests/scope/mod.rs

@@ -1,7 +1,10 @@
+use nu_test_support::fs::Stub::FileWithContent;
 use nu_test_support::nu;
+use nu_test_support::playground::Playground;
 use pretty_assertions::assert_eq;
 
-#[ignore = "TODO: This shows old-style aliases. New aliases are under commands"]
+// Note: These tests might slightly overlap with crates/nu-command/tests/commands/help.rs
+
 #[test]
 fn scope_shows_alias() {
     let actual = nu!("alias xaz = echo alias1
@@ -71,7 +74,7 @@ fn scope_doesnt_show_hidden_command() {
 }
 
 // same problem as 'which' command
-#[ignore]
+#[ignore = "See https://github.com/nushell/nushell/issues/4837"]
 #[test]
 fn correctly_report_of_shadowed_alias() {
     let actual = nu!("alias xaz = echo alias1
@@ -83,3 +86,163 @@ fn correctly_report_of_shadowed_alias() {
 
     assert_eq!(actual.out, "echo alias2");
 }
+
+#[test]
+fn correct_scope_modules_fields() {
+    let module_setup = r#"
+        # nice spam
+
+        export module eggs {
+            export module bacon {
+                export def sausage [] { 'sausage' }
+            }
+        }
+
+        export def main [] { 'foo' };
+        export alias xaz = print
+        export extern git []
+        export const X = 4
+
+        export-env { $env.SPAM = 'spam' }
+    "#;
+
+    Playground::setup("correct_scope_modules_fields", |dirs, sandbox| {
+        sandbox.with_files(vec![FileWithContent("spam.nu", module_setup)]);
+
+        let inp = &[
+            "use spam.nu",
+            "scope modules | where name == spam | get 0.name",
+        ];
+        let actual = nu!(cwd: dirs.test(), &inp.join("; "));
+        assert_eq!(actual.out, "spam");
+
+        let inp = &[
+            "use spam.nu",
+            "scope modules | where name == spam | get 0.usage",
+        ];
+        let actual = nu!(cwd: dirs.test(), &inp.join("; "));
+        assert_eq!(actual.out, "nice spam");
+
+        let inp = &[
+            "use spam.nu",
+            "scope modules | where name == spam | get 0.env_block | is-empty",
+        ];
+        let actual = nu!(cwd: dirs.test(), &inp.join("; "));
+        assert_eq!(actual.out, "false");
+
+        let inp = &[
+            "use spam.nu",
+            "scope modules | where name == spam | get 0.commands.0.name",
+        ];
+        let actual = nu!(cwd: dirs.test(), &inp.join("; "));
+        assert_eq!(actual.out, "spam");
+
+        let inp = &[
+            "use spam.nu",
+            "scope modules | where name == spam | get 0.aliases.0.name",
+        ];
+        let actual = nu!(cwd: dirs.test(), &inp.join("; "));
+        assert_eq!(actual.out, "xaz");
+
+        let inp = &[
+            "use spam.nu",
+            "scope modules | where name == spam | get 0.externs.0.name",
+        ];
+        let actual = nu!(cwd: dirs.test(), &inp.join("; "));
+        assert_eq!(actual.out, "git");
+
+        let inp = &[
+            "use spam.nu",
+            "scope modules | where name == spam | get 0.constants.0.name",
+        ];
+        let actual = nu!(cwd: dirs.test(), &inp.join("; "));
+        assert_eq!(actual.out, "X");
+
+        let inp = &[
+            "use spam.nu",
+            "scope modules | where name == spam | get 0.submodules.0.submodules.0.name",
+        ];
+        let actual = nu!(cwd: dirs.test(), &inp.join("; "));
+        assert_eq!(actual.out, "bacon");
+
+        let inp = &[
+            "use spam.nu",
+            "scope modules | where name == spam | get 0.submodules.0.submodules.0.commands.0.name",
+        ];
+        let actual = nu!(cwd: dirs.test(), &inp.join("; "));
+        assert_eq!(actual.out, "sausage");
+    })
+}
+
+#[test]
+fn correct_scope_aliases_fields() {
+    let module_setup = r#"
+        # nice alias
+        export alias xaz = print
+    "#;
+
+    Playground::setup("correct_scope_aliases_fields", |dirs, sandbox| {
+        sandbox.with_files(vec![FileWithContent("spam.nu", module_setup)]);
+
+        let inp = &[
+            "use spam.nu",
+            "scope aliases | where name == 'spam xaz' | get 0.name",
+        ];
+        let actual = nu!(cwd: dirs.test(), &inp.join("; "));
+        assert_eq!(actual.out, "spam xaz");
+
+        let inp = &[
+            "use spam.nu",
+            "scope aliases | where name == 'spam xaz' | get 0.expansion",
+        ];
+        let actual = nu!(cwd: dirs.test(), &inp.join("; "));
+        assert_eq!(actual.out, "print");
+
+        let inp = &[
+            "use spam.nu",
+            "scope aliases | where name == 'spam xaz' | get 0.usage",
+        ];
+        let actual = nu!(cwd: dirs.test(), &inp.join("; "));
+        assert_eq!(actual.out, "nice alias");
+
+        let inp = &[
+            "use spam.nu",
+            "scope aliases | where name == 'spam xaz' | get 0.decl_id | is-empty",
+        ];
+        let actual = nu!(cwd: dirs.test(), &inp.join("; "));
+        assert_eq!(actual.out, "false");
+    })
+}
+
+#[test]
+fn correct_scope_externs_fields() {
+    let module_setup = r#"
+        # nice extern
+        export extern git []
+    "#;
+
+    Playground::setup("correct_scope_aliases_fields", |dirs, sandbox| {
+        sandbox.with_files(vec![FileWithContent("spam.nu", module_setup)]);
+
+        let inp = &[
+            "use spam.nu",
+            "scope externs | where name == 'spam git' | get 0.name",
+        ];
+        let actual = nu!(cwd: dirs.test(), &inp.join("; "));
+        assert_eq!(actual.out, "spam git");
+
+        let inp = &[
+            "use spam.nu",
+            "scope externs | where name == 'spam git' | get 0.usage",
+        ];
+        let actual = nu!(cwd: dirs.test(), &inp.join("; "));
+        assert_eq!(actual.out, "nice extern");
+
+        let inp = &[
+            "use spam.nu",
+            "scope externs | where name == 'spam git' | get 0.decl_id | is-empty",
+        ];
+        let actual = nu!(cwd: dirs.test(), &inp.join("; "));
+        assert_eq!(actual.out, "false");
+    })
+}