feat: add FunctionDefinition::visibility

compiler/noirc_frontend/src/hir/comptime/interpreter/builtin.rs

@@ -154,6 +154,7 @@ impl Interpreter<'_, '_> {
             "function_def_set_unconstrained" => {
                 function_def_set_unconstrained(self, arguments, location)
             }
+            "function_def_visibility" => function_def_visibility(interner, arguments, location),
             "module_add_item" => module_add_item(self, arguments, location),
             "module_eq" => module_eq(arguments, location),
             "module_functions" => module_functions(self, arguments, location),
@@ -2830,6 +2831,18 @@ fn function_def_set_unconstrained(
     Ok(Value::Unit)
 }
 
+// fn visibility(self) -> Quoted
+fn function_def_visibility(
+    interner: &NodeInterner,
+    arguments: Vec<(Value, Location)>,
+    location: Location,
+) -> IResult<Value> {
+    let self_argument = check_one_argument(arguments, location)?;
+    let func_id = get_function_def(self_argument)?;
+    let visibility = interner.function_visibility(func_id);
+    Ok(visibility_to_quoted(visibility, location))
+}
+
 // fn add_item(self, item: Quoted)
 fn module_add_item(
     interpreter: &mut Interpreter,

docs/docs/noir/standard_library/meta/function_def.md

@@ -113,6 +113,15 @@ Mutates the function to be unconstrained (if `true` is given) or not (if `false`
 This is only valid on functions in the current crate which have not yet been resolved.
 This means any functions called at compile-time are invalid targets for this method.
 
+### visibility
+
+#include_code visibility noir_stdlib/src/meta/function_def.nr rust
+
+Returns the function's visibility as a `Quoted` value, which will be one of:
+- `quote { }`: the function is private
+- `quote { pub }`: the function is `pub`
+- `quote { pub(crate) }`: the function is `pub(crate)`
+
 ## Trait Implementations
 
 ```rust

noir_stdlib/src/meta/function_def.nr

@@ -71,6 +71,11 @@ impl FunctionDefinition {
     // docs:start:set_unconstrained
     pub comptime fn set_unconstrained(self, value: bool) {}
     // docs:end:set_unconstrained
+
+    #[builtin(function_def_visibility)]
+    // docs:start:visibility
+    pub comptime fn visibility(self) -> Quoted {}
+    // docs:end:visibility
 }
 
 impl crate::hash::Hash for FunctionDefinition {

test_programs/compile_success_empty/comptime_function_definition/src/main.nr

@@ -22,6 +22,9 @@ pub fn foo(
 #[check_named_attribute]
 fn some_test() {}
 
+#[check_visibility]
+pub(crate) fn pub_crate_fn() {}
+
 comptime fn function_attr(f: FunctionDefinition) {
     // Check FunctionDefinition::parameters
     let parameters = f.parameters();
@@ -48,11 +51,18 @@ comptime fn function_attr(f: FunctionDefinition) {
     assert_eq(f.name(), quote { foo });
 
     assert(f.has_named_attribute("function_attr"));
+
+    assert_eq(f.visibility(), quote { pub })
 }
 
 comptime fn check_named_attribute(f: FunctionDefinition) {
     assert(f.has_named_attribute("test"));
     assert(f.has_named_attribute("deprecated"));
+    assert_eq(f.visibility(), quote { })
+}
+
+comptime fn check_visibility(f: FunctionDefinition) {
+    assert_eq(f.visibility(), quote { pub(crate) })
 }
 
 #[mutate_add_one]
@@ -75,6 +85,7 @@ comptime fn mutate_add_one(f: FunctionDefinition) {
 
 fn main() {
     assert_eq(add_one(41), 42);
+    pub_crate_fn();
 }
 
 contract some_contract {