Allow exporting extern-wrapped (#10025)

crates/nu-cmd-lang/src/core_commands/export_extern_wrapped.rs

@@ -0,0 +1,56 @@
+use nu_protocol::ast::Call;
+use nu_protocol::engine::{Command, EngineState, Stack};
+use nu_protocol::{Category, Example, PipelineData, ShellError, Signature, SyntaxShape, Type};
+
+#[derive(Clone)]
+pub struct ExportExternWrapped;
+
+impl Command for ExportExternWrapped {
+    fn name(&self) -> &str {
+        "export extern-wrapped"
+    }
+
+    fn usage(&self) -> &str {
+        "Define an extern with a custom code block and export it from a module."
+    }
+
+    fn signature(&self) -> nu_protocol::Signature {
+        Signature::build("export extern-wrapped")
+            .input_output_types(vec![(Type::Nothing, Type::Nothing)])
+            .required("def_name", SyntaxShape::String, "definition name")
+            .required("params", SyntaxShape::Signature, "parameters")
+            .required("body", SyntaxShape::Block, "wrapper code block")
+            .category(Category::Core)
+    }
+
+    fn extra_usage(&self) -> &str {
+        r#"This command is a parser keyword. For details, check:
+  https://www.nushell.sh/book/thinking_in_nu.html"#
+    }
+
+    fn is_parser_keyword(&self) -> bool {
+        true
+    }
+
+    fn run(
+        &self,
+        _engine_state: &EngineState,
+        _stack: &mut Stack,
+        _call: &Call,
+        _input: PipelineData,
+    ) -> Result<PipelineData, ShellError> {
+        Ok(PipelineData::empty())
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![Example {
+            description: "Export the signature for an external command",
+            example: r#"export extern-wrapped my-echo [...rest] { echo $rest }"#,
+            result: None,
+        }]
+    }
+
+    fn search_terms(&self) -> Vec<&str> {
+        vec!["signature", "module", "declare"]
+    }
+}

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

@@ -15,6 +15,7 @@ mod export_const;
 mod export_def;
 mod export_def_env;
 mod export_extern;
+mod export_extern_wrapped;
 mod export_module;
 mod export_use;
 mod extern_;
@@ -55,6 +56,7 @@ pub use export_const::ExportConst;
 pub use export_def::ExportDef;
 pub use export_def_env::ExportDefEnv;
 pub use export_extern::ExportExtern;
+pub use export_extern_wrapped::ExportExternWrapped;
 pub use export_module::ExportModule;
 pub use export_use::ExportUse;
 pub use extern_::Extern;

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

@@ -33,6 +33,7 @@ pub fn create_default_context() -> EngineState {
             ExportDef,
             ExportDefEnv,
             ExportExtern,
+            ExportExternWrapped,
             ExportUse,
             ExportModule,
             Extern,

crates/nu-parser/src/parse_keywords.rs

@@ -49,6 +49,7 @@ pub const UNALIASABLE_PARSER_KEYWORDS: &[&[u8]] = &[
     b"extern",
     b"extern-wrapped",
     b"export extern",
+    b"export extern-wrapped",
     b"alias",
     b"export alias",
     b"export-env",
@@ -211,7 +212,7 @@ pub fn parse_def_predecl(working_set: &mut StateWorkingSet, spans: &[Span]) {
             }
 
             signature.name = name.clone();
-            //let decl = signature.predeclare();
+
             let decl = KnownExternal {
                 name,
                 usage: "run external command".into(),
@@ -536,10 +537,8 @@ pub fn parse_extern(
     // Checking that the function is used with the correct name
     // Maybe this is not necessary but it is a sanity check
 
-    let (name_span, split_id) = if spans.len() > 1
+    let (name_span, split_id) =
-        && (working_set.get_span_contents(spans[0]) == b"export"
+        if spans.len() > 1 && (working_set.get_span_contents(spans[0]) == b"export") {
-            || working_set.get_span_contents(spans[0]) == b"export-wrapped")
-    {
             (spans[1], 2)
         } else {
             (spans[0], 1)
@@ -548,7 +547,7 @@ pub fn parse_extern(
     let extern_call = working_set.get_span_contents(name_span).to_vec();
     if extern_call != b"extern" && extern_call != b"extern-wrapped" {
         working_set.error(ParseError::UnknownState(
-            "internal error: Wrong call name for extern function".into(),
+            "internal error: Wrong call name for extern or extern-wrapped command".into(),
             span(spans),
         ));
         return garbage_pipeline(spans);
@@ -1011,6 +1010,7 @@ pub fn parse_export_in_block(
         }
         b"export module" => parse_module(working_set, lite_command, None).0,
         b"export extern" => parse_extern(working_set, lite_command, None),
+        b"export extern-wrapped" => parse_extern(working_set, lite_command, None),
         _ => {
             working_set.error(ParseError::UnexpectedKeyword(
                 String::from_utf8_lossy(&full_name).to_string(),
@@ -1193,13 +1193,15 @@ pub fn parse_export_in_module(
                     comments: lite_command.comments.clone(),
                     parts: spans[1..].to_vec(),
                 };
+                let extern_name = [b"export ", kw_name].concat();
+
                 let pipeline = parse_extern(working_set, &lite_command, Some(module_name));
 
-                let export_def_decl_id = if let Some(id) = working_set.find_decl(b"export extern") {
+                let export_def_decl_id = if let Some(id) = working_set.find_decl(&extern_name) {
                     id
                 } else {
                     working_set.error(ParseError::InternalError(
-                        "missing 'export extern' command".into(),
+                        "missing 'export extern' or 'export extern-wrapped' command".into(),
                         export_span,
                     ));
                     return (garbage_pipeline(spans), vec![]);
@@ -1460,7 +1462,7 @@ pub fn parse_export_in_module(
             }
             _ => {
                 working_set.error(ParseError::Expected(
-                    "def, def-env, alias, use, module, or extern keyword",
+                    "def, def-env, alias, use, module, const, extern or extern-wrapped keyword",
                     spans[1],
                 ));
 
@@ -1469,9 +1471,9 @@ pub fn parse_export_in_module(
         }
     } else {
         working_set.error(ParseError::MissingPositional(
-            "def, def-env, extern, alias, use, or module keyword".into(),
+            "def, def-env, alias, use, module, const, extern or extern-wrapped keyword".to_string(),
             Span::new(export_span.end, export_span.end),
-            "def, def-env, extern, alias, use, or module keyword.".to_string(),
+            "def, def-env, alias, use, module, const, extern or extern-wrapped keyword".to_string(),
         ));
 
         vec![]
@@ -1794,7 +1796,7 @@ pub fn parse_module_block(
                         }
                         _ => {
                             working_set.error(ParseError::ExpectedKeyword(
-                                "def, const, def-env, extern, alias, use, module, export or export-env keyword".into(),
+                                "def, const, def-env, extern, extern-wrapped, alias, use, module, export or export-env keyword".into(),
                                 command.parts[0],
                             ));
 

src/tests/test_known_external.rs

@@ -39,6 +39,34 @@ fn known_external_complex_unknown_args() -> TestResult {
     )
 }
 
+#[test]
+fn known_external_from_module() -> TestResult {
+    run_test_contains(
+        r#"module spam {
+            export extern echo []
+        }
+
+        use spam echo
+        echo foo -b -as -9 --abc -- -Dxmy=AKOO - bar
+        "#,
+        "foo -b -as -9 --abc -- -Dxmy=AKOO - bar",
+    )
+}
+
+#[test]
+fn known_external_wrapped_from_module() -> TestResult {
+    run_test_contains(
+        r#"module spam {
+            export extern-wrapped my-echo [...rest] { ^echo $rest }
+        }
+
+        use spam
+        spam my-echo foo -b -as -9 --abc -- -Dxmy=AKOO - bar
+        "#,
+        "foo -b -as -9 --abc -- -Dxmy=AKOO - bar",
+    )
+}
+
 #[test]
 fn known_external_short_flag_batch_arg_allowed() -> TestResult {
     run_test_contains("extern echo [-a, -b: int]; echo -ab 10", "-b 10")

tests/shell/pipeline/commands/external.rs

@@ -121,7 +121,7 @@ fn command_not_found_error_suggests_typo_fix() {
 }
 
 #[test]
-fn command_not_found_error_shows_not_found() {
+fn command_not_found_error_shows_not_found_1() {
     let actual = nu!(r#"
             export extern "foo" [];
             foo
@@ -129,6 +129,15 @@ fn command_not_found_error_shows_not_found() {
     assert!(actual.err.contains("'foo' was not found"));
 }
 
+#[test]
+fn command_not_found_error_shows_not_found_2() {
+    let actual = nu!(r#"
+            export extern-wrapped my-foo [...rest] { foo };
+            my-foo
+        "#);
+    assert!(actual.err.contains("did you mean"));
+}
+
 #[test]
 fn command_substitution_wont_output_extra_newline() {
     let actual = nu!(r#"