From b7af715f6b4e46ddb5c2a574ceedf28e2e3ba46e Mon Sep 17 00:00:00 2001
From: Wind <WindSoilder@outlook.com>
Date: Thu, 7 Nov 2024 13:35:00 +0800
Subject: [PATCH] IR: Don't generate instructions for `def` and `export def`.
 (#14114)

# Description
Fixes: #14110
Fixes: #14087

I think it's ok to not generating instruction to `def` and `export def`
call. Because they just return `PipelineData::Empty` without doing
anything.

If nushell generates instructions for `def` and `export def`, nushell
will try to capture variables for these block. It's not the time to do
this.

# User-Facing Changes
```
nu -c "
def bar [] {
    let x = 1
    ($x | foo)
}
def foo [] {
    foo
}
"
```
Will no longer raise error.

# Tests + Formatting
Added 4 tests
---
 crates/nu-command/tests/commands/def.rs | 34 +++++++++++++++++++++++++
 crates/nu-engine/src/compile/call.rs    |  3 +++
 2 files changed, 37 insertions(+)

diff --git a/crates/nu-command/tests/commands/def.rs b/crates/nu-command/tests/commands/def.rs
index 0ec13c0511..c66869b479 100644
--- a/crates/nu-command/tests/commands/def.rs
+++ b/crates/nu-command/tests/commands/def.rs
@@ -292,3 +292,37 @@ fn def_env_wrapped_no_help() {
     let actual = nu!("def --wrapped foo [...rest] { echo $rest }; foo -h | to json --raw");
     assert_eq!(actual.out, r#"["-h"]"#);
 }
+
+#[test]
+fn def_recursive_func_should_work() {
+    let actual = nu!("def bar [] { let x = 1; ($x | foo) }; def foo [] { foo }");
+    assert!(actual.err.is_empty());
+
+    let actual = nu!(r#"
+def recursive [c: int] {
+    if ($c == 0) { return }
+    if ($c mod 2 > 0) {
+        $in | recursive ($c - 1)
+    } else {
+        recursive ($c - 1)
+    }
+}"#);
+    assert!(actual.err.is_empty());
+}
+
+#[test]
+fn export_def_recursive_func_should_work() {
+    let actual = nu!("export def bar [] { let x = 1; ($x | foo) }; export def foo [] { foo }");
+    assert!(actual.err.is_empty());
+
+    let actual = nu!(r#"
+export def recursive [c: int] {
+    if ($c == 0) { return }
+    if ($c mod 2 > 0) {
+        $in | recursive ($c - 1)
+    } else {
+        recursive ($c - 1)
+    }
+}"#);
+    assert!(actual.err.is_empty());
+}
diff --git a/crates/nu-engine/src/compile/call.rs b/crates/nu-engine/src/compile/call.rs
index e928b63826..4112e889b1 100644
--- a/crates/nu-engine/src/compile/call.rs
+++ b/crates/nu-engine/src/compile/call.rs
@@ -71,6 +71,9 @@ pub(crate) fn compile_call(
             "return" => {
                 return compile_return(working_set, builder, call, redirect_modes, io_reg);
             }
+            "def" | "export def" => {
+                return builder.load_empty(io_reg);
+            }
             _ => (),
         }
     }