Adds visibility check for fully qualified function (FuelLabs#4241)

## Description
The issue was that it was possible to call private methods in another
module by calling them with fully qualified paths.

The fix was to use resolve_call_path_with_visibility_check instead of
resolve_call_path.

Closes FuelLabs#4231.

## Checklist

- [x] I have linked to any relevant issues.
- [x] I have commented my code, particularly in hard-to-understand
areas.
- [ ] I have updated the documentation where relevant (API docs, the
reference, and the Sway book).
- [x] I have added tests that prove my fix is effective or that my
feature works.
- [x] I have added (or requested a maintainer to add) the necessary
`Breaking*` or `New Feature` labels where relevant.
- [x] I have done my best to ensure that my PR adheres to [the Fuel Labs
Code Review
Standards](https://github.com/FuelLabs/rfcs/blob/master/text/code-standards/external-contributors.md).
- [x] I have requested a review from the relevant team or maintainers.

---------

Co-authored-by: Mohammad Fawaz <[email protected]>

sway-core/src/semantic_analysis/namespace/namespace.rs

@@ -105,6 +105,16 @@ impl Namespace {
         self.root.resolve_call_path(&self.mod_path, call_path)
     }
 
+    /// Short-hand for calling [Root::resolve_call_path_with_visibility_check] on `root` with the `mod_path`.
+    pub(crate) fn resolve_call_path_with_visibility_check(
+        &self,
+        engines: Engines<'_>,
+        call_path: &CallPath,
+    ) -> CompileResult<&ty::TyDeclaration> {
+        self.root
+            .resolve_call_path_with_visibility_check(engines, &self.mod_path, call_path)
+    }
+
     /// Short-hand for calling [Root::resolve_type_with_self] on `root` with the `mod_path`.
     pub(crate) fn resolve_type_with_self(
         &mut self,

sway-core/src/semantic_analysis/namespace/root.rs

@@ -78,7 +78,9 @@ impl Root {
                     name: call_path.suffix.clone(),
                     span: call_path.suffix.span(),
                 });
-                return err(warnings, errors);
+                // Returns ok with error, this allows functions which call this to
+                // also access the returned TyDeclaration and throw more suitable errors.
+                return ok(decl, warnings, errors);
             }
         }
 

sway-core/src/type_system/binding.rs

@@ -219,7 +219,9 @@ impl TypeBinding<CallPath> {
 
         // grab the declaration
         let unknown_decl = check!(
-            ctx.namespace.resolve_call_path(&self.inner).cloned(),
+            ctx.namespace
+                .resolve_call_path_with_visibility_check(engines, &self.inner)
+                .cloned(),
             return err(warnings, errors),
             warnings,
             errors

test/src/e2e_vm_tests/test_programs/should_fail/generics_not_supported/src/inner_lib.sw

@@ -1,6 +1,6 @@
 library inner_lib;
 
-const C = 42;
+pub const C = 42;
 
 pub fn func() -> bool {
     true

test/src/e2e_vm_tests/test_programs/should_fail/private_function_fully_qualified/Forc.lock

@@ -0,0 +1,3 @@
+[[package]]
+name = 'private_function_fully_qualified'
+source = 'member'

test/src/e2e_vm_tests/test_programs/should_fail/private_function_fully_qualified/Forc.toml

@@ -0,0 +1,6 @@
+[project]
+authors = ["Fuel Labs <[email protected]>"]
+license = "Apache-2.0"
+name = "private_function_fully_qualified"
+entry = "main.sw"
+implicit-std = false

test/src/e2e_vm_tests/test_programs/should_fail/private_function_fully_qualified/src/main.sw

@@ -0,0 +1,7 @@
+script;
+
+dep pkga;
+
+fn main() {
+    pkga::foo();
+}

test/src/e2e_vm_tests/test_programs/should_fail/private_function_fully_qualified/src/pkga.sw

@@ -0,0 +1,3 @@
+library pkga;
+
+fn foo() { }

test/src/e2e_vm_tests/test_programs/should_fail/private_function_fully_qualified/test.toml

@@ -0,0 +1,3 @@
+category = "fail"
+
+# check: $()Symbol "foo" is private.

test/src/e2e_vm_tests/test_programs/should_pass/language/use_full_path_names/src/b_dependency.sw

@@ -1,5 +1,5 @@
 library bar;
 
-enum Bar {
+pub enum Bar {
     Baz: bool,
 }

test/src/e2e_vm_tests/test_programs/should_pass/language/use_full_path_names/src/c_dependency.sw

@@ -1,5 +1,5 @@
 library baz;
 
-fn return_1() -> u32 {
+pub fn return_1() -> u32 {
     1u32
 }

test/src/e2e_vm_tests/test_programs/should_pass/test_contracts/multiple_impl/src/testlib.sw

@@ -1,5 +1,5 @@
 library testlib;
 
-fn foo() {
+pub fn foo() {
     log(1);
 }