Merge pull request #1739 from fzyzcjy/feat/11840

Improve hints when using non-meaningful `&mut`

frb_codegen/src/library/codegen/parser/function_parser/argument.rs

@@ -2,6 +2,7 @@ use crate::codegen::ir::field::{IrField, IrFieldSettings};
 use crate::codegen::ir::func::{IrFuncMode, IrFuncOwnerInfo};
 use crate::codegen::ir::ident::IrIdent;
 use crate::codegen::ir::ty::boxed::IrTypeBoxed;
+use crate::codegen::ir::ty::rust_auto_opaque::OwnershipMode;
 use crate::codegen::ir::ty::IrType;
 use crate::codegen::ir::ty::IrType::Boxed;
 use crate::codegen::parser::attribute_parser::FrbAttributes;
@@ -11,7 +12,7 @@ use crate::codegen::parser::function_parser::{
 use crate::codegen::parser::type_parser::misc::parse_comments;
 use crate::codegen::parser::type_parser::TypeParserParsingContext;
 use crate::if_then_some;
-use anyhow::{bail, Context};
+use anyhow::{bail, ensure, Context};
 use syn::*;
 
 impl<'a, 'b> FunctionParser<'a, 'b> {
@@ -76,6 +77,11 @@ impl<'a, 'b> FunctionParser<'a, 'b> {
                     ..Default::default()
                 });
             }
+
+            ensure!(
+                parse_receiver_ownership_mode(receiver) == OwnershipMode::Ref,
+                "If you want to use `self`/`&mut self`, please make the struct opaque (by adding `#[frb(opaque)]` on the struct)."
+            );
         }
 
         partial_info_for_normal_type_raw(ty, &receiver.attrs, name)
@@ -184,13 +190,21 @@ fn parse_name_from_pat_type(pat_type: &PatType) -> anyhow::Result<String> {
 }
 
 fn generate_ref_type_considering_reference(raw: &str, receiver: &Receiver) -> String {
+    match parse_receiver_ownership_mode(receiver) {
+        OwnershipMode::Owned => raw.to_owned(),
+        OwnershipMode::RefMut => format!("&mut {raw}"),
+        OwnershipMode::Ref => format!("&{raw}"),
+    }
+}
+
+fn parse_receiver_ownership_mode(receiver: &Receiver) -> OwnershipMode {
     if receiver.reference.is_some() {
         if receiver.mutability.is_some() {
-            format!("&mut {raw}")
+            OwnershipMode::RefMut
         } else {
-            format!("&{raw}")
+            OwnershipMode::Ref
         }
     } else {
-        raw.to_owned()
+        OwnershipMode::Owned
     }
 }

frb_codegen/src/library/codegen/parser/mod.rs

@@ -145,13 +145,14 @@ mod tests {
     use crate::codegen::parser::parse;
     use crate::codegen::parser::reader::CachedRustReader;
     use crate::codegen::parser::source_graph::crates::Crate;
+    use crate::codegen::parser::IrPack;
     use crate::utils::logs::configure_opinionated_test_logging;
     use crate::utils::test_utils::{
         create_path_sanitizers, get_test_fixture_dir, json_golden_test,
     };
     use log::info;
     use serial_test::serial;
-    use std::path::Path;
+    use std::path::{Path, PathBuf};
 
     #[test]
     #[serial]
@@ -204,11 +205,35 @@ mod tests {
         body("library/codegen/parser/mod/generics", None)
     }
 
+    #[test]
+    #[serial]
+    fn test_error_non_opaque_mut() -> anyhow::Result<()> {
+        let result = execute_parse("library/codegen/parser/mod/error_non_opaque_mut", None);
+        assert!(format!("{:#?}", result.err().unwrap())
+            .contains("If you want to use `self`/`&mut self`"));
+        Ok(())
+    }
+
     #[allow(clippy::type_complexity)]
     fn body(
         fixture_name: &str,
         rust_input_path_pack: Option<Box<dyn Fn(&Path) -> RustInputPathPack>>,
     ) -> anyhow::Result<()> {
+        let (actual_ir, rust_crate_dir) = execute_parse(fixture_name, rust_input_path_pack)?;
+        json_golden_test(
+            &serde_json::to_value(actual_ir)?,
+            &rust_crate_dir.join("expect_ir.json"),
+            &[],
+        )?;
+
+        Ok(())
+    }
+
+    #[allow(clippy::type_complexity)]
+    fn execute_parse(
+        fixture_name: &str,
+        rust_input_path_pack: Option<Box<dyn Fn(&Path) -> RustInputPathPack>>,
+    ) -> anyhow::Result<(IrPack, PathBuf)> {
         configure_opinionated_test_logging();
         let test_fixture_dir = get_test_fixture_dir(fixture_name);
         let rust_crate_dir = test_fixture_dir.clone();
@@ -223,9 +248,10 @@ mod tests {
             &serde_json::to_value(crate_map)?,
             &rust_crate_dir.join("expect_source_graph.json"),
             &create_path_sanitizers(&test_fixture_dir),
-        )?;
+        )
+        .unwrap();
 
-        let actual_ir = parse(
+        let pack = parse(
             &ParserInternalConfig {
                 rust_input_path_pack: rust_input_path_pack.map(|f| f(&rust_crate_dir)).unwrap_or(
                     RustInputPathPack {
@@ -240,12 +266,7 @@ mod tests {
             &Dumper(&Default::default()),
             &GeneratorProgressBarPack::new(),
         )?;
-        json_golden_test(
-            &serde_json::to_value(actual_ir)?,
-            &rust_crate_dir.join("expect_ir.json"),
-            &[],
-        )?;
 
-        Ok(())
+        Ok((pack, rust_crate_dir))
     }
 }

frb_codegen/test_fixtures/library/codegen/parser/mod/error_non_opaque_mut/Cargo.toml

@@ -0,0 +1,10 @@
+[package]
+name = "example"
+version = "0.1.0"
+edition = "2018"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+
+[workspace]

frb_codegen/test_fixtures/library/codegen/parser/mod/error_non_opaque_mut/expect_source_graph.json

@@ -0,0 +1,47 @@
+{
+  "manifest_path": "{the-working-directory}/Cargo.toml",
+  "name": "example",
+  "root_module": {
+    "info": {
+      "file_path": "{the-working-directory}/src/lib.rs",
+      "module_path": [
+        "crate"
+      ],
+      "visibility": "Public"
+    },
+    "scope": {
+      "enums": [],
+      "modules": [
+        {
+          "info": {
+            "file_path": "{the-working-directory}/src/api.rs",
+            "module_path": [
+              "crate",
+              "api"
+            ],
+            "visibility": "Inherited"
+          },
+          "scope": {
+            "enums": [],
+            "modules": [],
+            "structs": [
+              {
+                "ident": "MyStruct",
+                "mirror": false,
+                "path": [
+                  "crate",
+                  "api",
+                  "MyStruct"
+                ],
+                "visibility": "Public"
+              }
+            ],
+            "type_alias": []
+          }
+        }
+      ],
+      "structs": [],
+      "type_alias": []
+    }
+  }
+}

frb_codegen/test_fixtures/library/codegen/parser/mod/error_non_opaque_mut/src/api.rs

@@ -0,0 +1,7 @@
+pub struct MyStruct {
+    my_field: String,
+}
+
+impl MyStruct {
+    pub fn my_mut_method(&mut self) {}
+}

frb_codegen/test_fixtures/library/codegen/parser/mod/error_non_opaque_mut/src/lib.rs

@@ -0,0 +1 @@
+mod api;