1 files changed, 607 insertions, 0 deletions

diff --git a/crates/assists/src/handlers/fix_visibility.rs b/crates/assists/src/handlers/fix_visibility.rs
new file mode 100644
index 000000000..7cd76ea06
--- /dev/null
+++ b/crates/assists/src/handlers/fix_visibility.rs
@@ -0,0 +1,607 @@
+use base_db::FileId;
+use hir::{db::HirDatabase, HasSource, HasVisibility, PathResolution};
+use syntax::{ast, AstNode, TextRange, TextSize};
+
+use crate::{utils::vis_offset, AssistContext, AssistId, AssistKind, Assists};
+use ast::VisibilityOwner;
+
+// FIXME: this really should be a fix for diagnostic, rather than an assist.
+
+// Assist: fix_visibility
+//
+// Makes inaccessible item public.
+//
+// ```
+// mod m {
+//     fn frobnicate() {}
+// }
+// fn main() {
+//     m::frobnicate<|>() {}
+// }
+// ```
+// ->
+// ```
+// mod m {
+//     $0pub(crate) fn frobnicate() {}
+// }
+// fn main() {
+//     m::frobnicate() {}
+// }
+// ```
+pub(crate) fn fix_visibility(acc: &mut Assists, ctx: &AssistContext) -> Option<()> {
+    add_vis_to_referenced_module_def(acc, ctx)
+        .or_else(|| add_vis_to_referenced_record_field(acc, ctx))
+}
+
+fn add_vis_to_referenced_module_def(acc: &mut Assists, ctx: &AssistContext) -> Option<()> {
+    let path: ast::Path = ctx.find_node_at_offset()?;
+    let path_res = ctx.sema.resolve_path(&path)?;
+    let def = match path_res {
+        PathResolution::Def(def) => def,
+        _ => return None,
+    };
+
+    let current_module = ctx.sema.scope(&path.syntax()).module()?;
+    let target_module = def.module(ctx.db())?;
+
+    let vis = target_module.visibility_of(ctx.db(), &def)?;
+    if vis.is_visible_from(ctx.db(), current_module.into()) {
+        return None;
+    };
+
+    let (offset, current_visibility, target, target_file, target_name) =
+        target_data_for_def(ctx.db(), def)?;
+
+    let missing_visibility =
+        if current_module.krate() == target_module.krate() { "pub(crate)" } else { "pub" };
+
+    let assist_label = match target_name {
+        None => format!("Change visibility to {}", missing_visibility),
+        Some(name) => format!("Change visibility of {} to {}", name, missing_visibility),
+    };
+
+    acc.add(AssistId("fix_visibility", AssistKind::QuickFix), assist_label, target, |builder| {
+        builder.edit_file(target_file);
+        match ctx.config.snippet_cap {
+            Some(cap) => match current_visibility {
+                Some(current_visibility) => builder.replace_snippet(
+                    cap,
+                    current_visibility.syntax().text_range(),
+                    format!("$0{}", missing_visibility),
+                ),
+                None => builder.insert_snippet(cap, offset, format!("$0{} ", missing_visibility)),
+            },
+            None => match current_visibility {
+                Some(current_visibility) => {
+                    builder.replace(current_visibility.syntax().text_range(), missing_visibility)
+                }
+                None => builder.insert(offset, format!("{} ", missing_visibility)),
+            },
+        }
+    })
+}
+
+fn add_vis_to_referenced_record_field(acc: &mut Assists, ctx: &AssistContext) -> Option<()> {
+    let record_field: ast::RecordExprField = ctx.find_node_at_offset()?;
+    let (record_field_def, _) = ctx.sema.resolve_record_field(&record_field)?;
+
+    let current_module = ctx.sema.scope(record_field.syntax()).module()?;
+    let visibility = record_field_def.visibility(ctx.db());
+    if visibility.is_visible_from(ctx.db(), current_module.into()) {
+        return None;
+    }
+
+    let parent = record_field_def.parent_def(ctx.db());
+    let parent_name = parent.name(ctx.db());
+    let target_module = parent.module(ctx.db());
+
+    let in_file_source = record_field_def.source(ctx.db());
+    let (offset, current_visibility, target) = match in_file_source.value {
+        hir::FieldSource::Named(it) => {
+            let s = it.syntax();
+            (vis_offset(s), it.visibility(), s.text_range())
+        }
+        hir::FieldSource::Pos(it) => {
+            let s = it.syntax();
+            (vis_offset(s), it.visibility(), s.text_range())
+        }
+    };
+
+    let missing_visibility =
+        if current_module.krate() == target_module.krate() { "pub(crate)" } else { "pub" };
+    let target_file = in_file_source.file_id.original_file(ctx.db());
+
+    let target_name = record_field_def.name(ctx.db());
+    let assist_label =
+        format!("Change visibility of {}.{} to {}", parent_name, target_name, missing_visibility);
+
+    acc.add(AssistId("fix_visibility", AssistKind::QuickFix), assist_label, target, |builder| {
+        builder.edit_file(target_file);
+        match ctx.config.snippet_cap {
+            Some(cap) => match current_visibility {
+                Some(current_visibility) => builder.replace_snippet(
+                    cap,
+                    current_visibility.syntax().text_range(),
+                    format!("$0{}", missing_visibility),
+                ),
+                None => builder.insert_snippet(cap, offset, format!("$0{} ", missing_visibility)),
+            },
+            None => match current_visibility {
+                Some(current_visibility) => {
+                    builder.replace(current_visibility.syntax().text_range(), missing_visibility)
+                }
+                None => builder.insert(offset, format!("{} ", missing_visibility)),
+            },
+        }
+    })
+}
+
+fn target_data_for_def(
+    db: &dyn HirDatabase,
+    def: hir::ModuleDef,
+) -> Option<(TextSize, Option<ast::Visibility>, TextRange, FileId, Option<hir::Name>)> {
+    fn offset_target_and_file_id<S, Ast>(
+        db: &dyn HirDatabase,
+        x: S,
+    ) -> (TextSize, Option<ast::Visibility>, TextRange, FileId)
+    where
+        S: HasSource<Ast = Ast>,
+        Ast: AstNode + ast::VisibilityOwner,
+    {
+        let source = x.source(db);
+        let in_file_syntax = source.syntax();
+        let file_id = in_file_syntax.file_id;
+        let syntax = in_file_syntax.value;
+        let current_visibility = source.value.visibility();
+        (
+            vis_offset(syntax),
+            current_visibility,
+            syntax.text_range(),
+            file_id.original_file(db.upcast()),
+        )
+    }
+
+    let target_name;
+    let (offset, current_visibility, target, target_file) = match def {
+        hir::ModuleDef::Function(f) => {
+            target_name = Some(f.name(db));
+            offset_target_and_file_id(db, f)
+        }
+        hir::ModuleDef::Adt(adt) => {
+            target_name = Some(adt.name(db));
+            match adt {
+                hir::Adt::Struct(s) => offset_target_and_file_id(db, s),
+                hir::Adt::Union(u) => offset_target_and_file_id(db, u),
+                hir::Adt::Enum(e) => offset_target_and_file_id(db, e),
+            }
+        }
+        hir::ModuleDef::Const(c) => {
+            target_name = c.name(db);
+            offset_target_and_file_id(db, c)
+        }
+        hir::ModuleDef::Static(s) => {
+            target_name = s.name(db);
+            offset_target_and_file_id(db, s)
+        }
+        hir::ModuleDef::Trait(t) => {
+            target_name = Some(t.name(db));
+            offset_target_and_file_id(db, t)
+        }
+        hir::ModuleDef::TypeAlias(t) => {
+            target_name = Some(t.name(db));
+            offset_target_and_file_id(db, t)
+        }
+        hir::ModuleDef::Module(m) => {
+            target_name = m.name(db);
+            let in_file_source = m.declaration_source(db)?;
+            let file_id = in_file_source.file_id.original_file(db.upcast());
+            let syntax = in_file_source.value.syntax();
+            (vis_offset(syntax), in_file_source.value.visibility(), syntax.text_range(), file_id)
+        }
+        // Enum variants can't be private, we can't modify builtin types
+        hir::ModuleDef::EnumVariant(_) | hir::ModuleDef::BuiltinType(_) => return None,
+    };
+
+    Some((offset, current_visibility, target, target_file, target_name))
+}
+
+#[cfg(test)]
+mod tests {
+    use crate::tests::{check_assist, check_assist_not_applicable};
+
+    use super::*;
+
+    #[test]
+    fn fix_visibility_of_fn() {
+        check_assist(
+            fix_visibility,
+            r"mod foo { fn foo() {} }
+              fn main() { foo::foo<|>() } ",
+            r"mod foo { $0pub(crate) fn foo() {} }
+              fn main() { foo::foo() } ",
+        );
+        check_assist_not_applicable(
+            fix_visibility,
+            r"mod foo { pub fn foo() {} }
+              fn main() { foo::foo<|>() } ",
+        )
+    }
+
+    #[test]
+    fn fix_visibility_of_adt_in_submodule() {
+        check_assist(
+            fix_visibility,
+            r"mod foo { struct Foo; }
+              fn main() { foo::Foo<|> } ",
+            r"mod foo { $0pub(crate) struct Foo; }
+              fn main() { foo::Foo } ",
+        );
+        check_assist_not_applicable(
+            fix_visibility,
+            r"mod foo { pub struct Foo; }
+              fn main() { foo::Foo<|> } ",
+        );
+        check_assist(
+            fix_visibility,
+            r"mod foo { enum Foo; }
+              fn main() { foo::Foo<|> } ",
+            r"mod foo { $0pub(crate) enum Foo; }
+              fn main() { foo::Foo } ",
+        );
+        check_assist_not_applicable(
+            fix_visibility,
+            r"mod foo { pub enum Foo; }
+              fn main() { foo::Foo<|> } ",
+        );
+        check_assist(
+            fix_visibility,
+            r"mod foo { union Foo; }
+              fn main() { foo::Foo<|> } ",
+            r"mod foo { $0pub(crate) union Foo; }
+              fn main() { foo::Foo } ",
+        );
+        check_assist_not_applicable(
+            fix_visibility,
+            r"mod foo { pub union Foo; }
+              fn main() { foo::Foo<|> } ",
+        );
+    }
+
+    #[test]
+    fn fix_visibility_of_adt_in_other_file() {
+        check_assist(
+            fix_visibility,
+            r"
+//- /main.rs
+mod foo;
+fn main() { foo::Foo<|> }
+
+//- /foo.rs
+struct Foo;
+",
+            r"$0pub(crate) struct Foo;
+",
+        );
+    }
+
+    #[test]
+    fn fix_visibility_of_struct_field() {
+        check_assist(
+            fix_visibility,
+            r"mod foo { pub struct Foo { bar: (), } }
+              fn main() { foo::Foo { <|>bar: () }; } ",
+            r"mod foo { pub struct Foo { $0pub(crate) bar: (), } }
+              fn main() { foo::Foo { bar: () }; } ",
+        );
+        check_assist(
+            fix_visibility,
+            r"
+//- /lib.rs
+mod foo;
+fn main() { foo::Foo { <|>bar: () }; }
+//- /foo.rs
+pub struct Foo { bar: () }
+",
+            r"pub struct Foo { $0pub(crate) bar: () }
+",
+        );
+        check_assist_not_applicable(
+            fix_visibility,
+            r"mod foo { pub struct Foo { pub bar: (), } }
+              fn main() { foo::Foo { <|>bar: () }; } ",
+        );
+        check_assist_not_applicable(
+            fix_visibility,
+            r"
+//- /lib.rs
+mod foo;
+fn main() { foo::Foo { <|>bar: () }; }
+//- /foo.rs
+pub struct Foo { pub bar: () }
+",
+        );
+    }
+
+    #[test]
+    fn fix_visibility_of_enum_variant_field() {
+        check_assist(
+            fix_visibility,
+            r"mod foo { pub enum Foo { Bar { bar: () } } }
+              fn main() { foo::Foo::Bar { <|>bar: () }; } ",
+            r"mod foo { pub enum Foo { Bar { $0pub(crate) bar: () } } }
+              fn main() { foo::Foo::Bar { bar: () }; } ",
+        );
+        check_assist(
+            fix_visibility,
+            r"
+//- /lib.rs
+mod foo;
+fn main() { foo::Foo::Bar { <|>bar: () }; }
+//- /foo.rs
+pub enum Foo { Bar { bar: () } }
+",
+            r"pub enum Foo { Bar { $0pub(crate) bar: () } }
+",
+        );
+        check_assist_not_applicable(
+            fix_visibility,
+            r"mod foo { pub struct Foo { pub bar: (), } }
+              fn main() { foo::Foo { <|>bar: () }; } ",
+        );
+        check_assist_not_applicable(
+            fix_visibility,
+            r"
+//- /lib.rs
+mod foo;
+fn main() { foo::Foo { <|>bar: () }; }
+//- /foo.rs
+pub struct Foo { pub bar: () }
+",
+        );
+    }
+
+    #[test]
+    #[ignore]
+    // FIXME reenable this test when `Semantics::resolve_record_field` works with union fields
+    fn fix_visibility_of_union_field() {
+        check_assist(
+            fix_visibility,
+            r"mod foo { pub union Foo { bar: (), } }
+              fn main() { foo::Foo { <|>bar: () }; } ",
+            r"mod foo { pub union Foo { $0pub(crate) bar: (), } }
+              fn main() { foo::Foo { bar: () }; } ",
+        );
+        check_assist(
+            fix_visibility,
+            r"
+//- /lib.rs
+mod foo;
+fn main() { foo::Foo { <|>bar: () }; }
+//- /foo.rs
+pub union Foo { bar: () }
+",
+            r"pub union Foo { $0pub(crate) bar: () }
+",
+        );
+        check_assist_not_applicable(
+            fix_visibility,
+            r"mod foo { pub union Foo { pub bar: (), } }
+              fn main() { foo::Foo { <|>bar: () }; } ",
+        );
+        check_assist_not_applicable(
+            fix_visibility,
+            r"
+//- /lib.rs
+mod foo;
+fn main() { foo::Foo { <|>bar: () }; }
+//- /foo.rs
+pub union Foo { pub bar: () }
+",
+        );
+    }
+
+    #[test]
+    fn fix_visibility_of_const() {
+        check_assist(
+            fix_visibility,
+            r"mod foo { const FOO: () = (); }
+              fn main() { foo::FOO<|> } ",
+            r"mod foo { $0pub(crate) const FOO: () = (); }
+              fn main() { foo::FOO } ",
+        );
+        check_assist_not_applicable(
+            fix_visibility,
+            r"mod foo { pub const FOO: () = (); }
+              fn main() { foo::FOO<|> } ",
+        );
+    }
+
+    #[test]
+    fn fix_visibility_of_static() {
+        check_assist(
+            fix_visibility,
+            r"mod foo { static FOO: () = (); }
+              fn main() { foo::FOO<|> } ",
+            r"mod foo { $0pub(crate) static FOO: () = (); }
+              fn main() { foo::FOO } ",
+        );
+        check_assist_not_applicable(
+            fix_visibility,
+            r"mod foo { pub static FOO: () = (); }
+              fn main() { foo::FOO<|> } ",
+        );
+    }
+
+    #[test]
+    fn fix_visibility_of_trait() {
+        check_assist(
+            fix_visibility,
+            r"mod foo { trait Foo { fn foo(&self) {} } }
+              fn main() { let x: &dyn foo::<|>Foo; } ",
+            r"mod foo { $0pub(crate) trait Foo { fn foo(&self) {} } }
+              fn main() { let x: &dyn foo::Foo; } ",
+        );
+        check_assist_not_applicable(
+            fix_visibility,
+            r"mod foo { pub trait Foo { fn foo(&self) {} } }
+              fn main() { let x: &dyn foo::Foo<|>; } ",
+        );
+    }
+
+    #[test]
+    fn fix_visibility_of_type_alias() {
+        check_assist(
+            fix_visibility,
+            r"mod foo { type Foo = (); }
+              fn main() { let x: foo::Foo<|>; } ",
+            r"mod foo { $0pub(crate) type Foo = (); }
+              fn main() { let x: foo::Foo; } ",
+        );
+        check_assist_not_applicable(
+            fix_visibility,
+            r"mod foo { pub type Foo = (); }
+              fn main() { let x: foo::Foo<|>; } ",
+        );
+    }
+
+    #[test]
+    fn fix_visibility_of_module() {
+        check_assist(
+            fix_visibility,
+            r"mod foo { mod bar { fn bar() {} } }
+              fn main() { foo::bar<|>::bar(); } ",
+            r"mod foo { $0pub(crate) mod bar { fn bar() {} } }
+              fn main() { foo::bar::bar(); } ",
+        );
+
+        check_assist(
+            fix_visibility,
+            r"
+//- /main.rs
+mod foo;
+fn main() { foo::bar<|>::baz(); }
+
+//- /foo.rs
+mod bar {
+    pub fn baz() {}
+}
+",
+            r"$0pub(crate) mod bar {
+    pub fn baz() {}
+}
+",
+        );
+
+        check_assist_not_applicable(
+            fix_visibility,
+            r"mod foo { pub mod bar { pub fn bar() {} } }
+              fn main() { foo::bar<|>::bar(); } ",
+        );
+    }
+
+    #[test]
+    fn fix_visibility_of_inline_module_in_other_file() {
+        check_assist(
+            fix_visibility,
+            r"
+//- /main.rs
+mod foo;
+fn main() { foo::bar<|>::baz(); }
+
+//- /foo.rs
+mod bar;
+//- /foo/bar.rs
+pub fn baz() {}
+",
+            r"$0pub(crate) mod bar;
+",
+        );
+    }
+
+    #[test]
+    fn fix_visibility_of_module_declaration_in_other_file() {
+        check_assist(
+            fix_visibility,
+            r"
+//- /main.rs
+mod foo;
+fn main() { foo::bar<|>>::baz(); }
+
+//- /foo.rs
+mod bar {
+    pub fn baz() {}
+}
+",
+            r"$0pub(crate) mod bar {
+    pub fn baz() {}
+}
+",
+        );
+    }
+
+    #[test]
+    fn adds_pub_when_target_is_in_another_crate() {
+        check_assist(
+            fix_visibility,
+            r"
+//- /main.rs crate:a deps:foo
+foo::Bar<|>
+//- /lib.rs crate:foo
+struct Bar;
+",
+            r"$0pub struct Bar;
+",
+        )
+    }
+
+    #[test]
+    fn replaces_pub_crate_with_pub() {
+        check_assist(
+            fix_visibility,
+            r"
+//- /main.rs crate:a deps:foo
+foo::Bar<|>
+//- /lib.rs crate:foo
+pub(crate) struct Bar;
+",
+            r"$0pub struct Bar;
+",
+        );
+        check_assist(
+            fix_visibility,
+            r"
+//- /main.rs crate:a deps:foo
+fn main() {
+    foo::Foo { <|>bar: () };
+}
+//- /lib.rs crate:foo
+pub struct Foo { pub(crate) bar: () }
+",
+            r"pub struct Foo { $0pub bar: () }
+",
+        );
+    }
+
+    #[test]
+    #[ignore]
+    // FIXME handle reexports properly
+    fn fix_visibility_of_reexport() {
+        check_assist(
+            fix_visibility,
+            r"
+            mod foo {
+                use bar::Baz;
+                mod bar { pub(super) struct Baz; }
+            }
+            foo::Baz<|>
+            ",
+            r"
+            mod foo {
+                $0pub(crate) use bar::Baz;
+                mod bar { pub(super) struct Baz; }
+            }
+            foo::Baz
+            ",
+        )
+    }
+}