13 files changed, 365 insertions, 205 deletions

diff --git a/crates/hir_def/src/body.rs b/crates/hir_def/src/body.rs
index 9a432f7d1..ff4b4a0cf 100644
--- a/crates/hir_def/src/body.rs
+++ b/crates/hir_def/src/body.rs
@@ -123,7 +123,7 @@ impl Expander {
             Some(it) => it,
             None => {
                 if err.is_none() {
-                    eprintln!("no error despite `as_call_id_with_errors` returning `None`");
+                    log::warn!("no error despite `as_call_id_with_errors` returning `None`");
                 }
                 return ExpandResult { value: None, err };
             }
diff --git a/crates/hir_def/src/body/lower.rs b/crates/hir_def/src/body/lower.rs
index c18001e15..40beb2f7a 100644
--- a/crates/hir_def/src/body/lower.rs
+++ b/crates/hir_def/src/body/lower.rs
@@ -24,7 +24,7 @@ use test_utils::mark;
 use crate::{
     adt::StructKind,
     body::{Body, BodySourceMap, Expander, LabelSource, PatPtr, SyntheticSyntax},
-    builtin_type::{BuiltinFloat, BuiltinInt},
+    builtin_type::{BuiltinFloat, BuiltinInt, BuiltinUint},
     db::DefDatabase,
     diagnostics::{InactiveCode, MacroError, UnresolvedProcMacro},
     expr::{
@@ -1065,11 +1065,16 @@ impl From<ast::LiteralKind> for Literal {
     fn from(ast_lit_kind: ast::LiteralKind) -> Self {
         match ast_lit_kind {
             LiteralKind::IntNumber(lit) => {
-                if let Some(float_suffix) = lit.suffix().and_then(BuiltinFloat::from_suffix) {
-                    return Literal::Float(Default::default(), Some(float_suffix));
+                if let builtin @ Some(_) = lit.suffix().and_then(BuiltinFloat::from_suffix) {
+                    return Literal::Float(Default::default(), builtin);
+                } else if let builtin @ Some(_) =
+                    lit.suffix().and_then(|it| BuiltinInt::from_suffix(&it))
+                {
+                    Literal::Int(Default::default(), builtin)
+                } else {
+                    let builtin = lit.suffix().and_then(|it| BuiltinUint::from_suffix(&it));
+                    Literal::Uint(Default::default(), builtin)
                 }
-                let ty = lit.suffix().and_then(|it| BuiltinInt::from_suffix(&it));
-                Literal::Int(Default::default(), ty)
             }
             LiteralKind::FloatNumber(lit) => {
                 let ty = lit.suffix().and_then(|it| BuiltinFloat::from_suffix(&it));
@@ -1077,7 +1082,7 @@ impl From<ast::LiteralKind> for Literal {
             }
             LiteralKind::ByteString(_) => Literal::ByteString(Default::default()),
             LiteralKind::String(_) => Literal::String(Default::default()),
-            LiteralKind::Byte => Literal::Int(Default::default(), Some(BuiltinInt::U8)),
+            LiteralKind::Byte => Literal::Uint(Default::default(), Some(BuiltinUint::U8)),
             LiteralKind::Bool(val) => Literal::Bool(val),
             LiteralKind::Char => Literal::Char(Default::default()),
         }
diff --git a/crates/hir_def/src/body/tests/block.rs b/crates/hir_def/src/body/tests/block.rs
index a5ec0883f..8bca72a17 100644
--- a/crates/hir_def/src/body/tests/block.rs
+++ b/crates/hir_def/src/body/tests/block.rs
@@ -259,3 +259,32 @@ fn main() {
     "#]],
     );
 }
+
+#[test]
+fn underscore_import() {
+    // This used to panic, because the default (private) visibility inside block expressions would
+    // point into the containing `DefMap`, which visibilities should never be able to do.
+    mark::check!(adjust_vis_in_block_def_map);
+    check_at(
+        r#"
+mod m {
+    fn main() {
+        use Tr as _;
+        trait Tr {}
+        $0
+    }
+}
+    "#,
+        expect![[r#"
+        block scope
+        _: t
+        Tr: t
+
+        crate
+        m: t
+
+        crate::m
+        main: v
+    "#]],
+    );
+}
diff --git a/crates/hir_def/src/builtin_type.rs b/crates/hir_def/src/builtin_type.rs
index 0f872b5c0..7cbaf30b8 100644
--- a/crates/hir_def/src/builtin_type.rs
+++ b/crates/hir_def/src/builtin_type.rs
@@ -6,38 +6,32 @@
 use std::fmt;
 
 use hir_expand::name::{name, AsName, Name};
-
-#[derive(Debug, Copy, Clone, Eq, PartialEq, Hash)]
-pub enum Signedness {
-    Signed,
-    Unsigned,
-}
-
-#[derive(Debug, Copy, Clone, Eq, PartialEq, Hash)]
-pub enum IntBitness {
-    Xsize,
-    X8,
-    X16,
-    X32,
-    X64,
-    X128,
-}
-
-#[derive(Debug, Copy, Clone, Eq, PartialEq, Hash)]
-pub enum FloatBitness {
-    X32,
-    X64,
+/// Different signed int types.
+#[derive(Copy, Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
+pub enum BuiltinInt {
+    Isize,
+    I8,
+    I16,
+    I32,
+    I64,
+    I128,
 }
 
-#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
-pub struct BuiltinInt {
-    pub signedness: Signedness,
-    pub bitness: IntBitness,
+/// Different unsigned int types.
+#[derive(Copy, Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
+pub enum BuiltinUint {
+    Usize,
+    U8,
+    U16,
+    U32,
+    U64,
+    U128,
 }
 
-#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
-pub struct BuiltinFloat {
-    pub bitness: FloatBitness,
+#[derive(Copy, Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
+pub enum BuiltinFloat {
+    F32,
+    F64,
 }
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
@@ -46,6 +40,7 @@ pub enum BuiltinType {
     Bool,
     Str,
     Int(BuiltinInt),
+    Uint(BuiltinUint),
     Float(BuiltinFloat),
 }
 
@@ -56,19 +51,19 @@ impl BuiltinType {
         (name![bool], BuiltinType::Bool),
         (name![str],  BuiltinType::Str),
 
-        (name![isize], BuiltinType::Int(BuiltinInt::ISIZE)),
+        (name![isize], BuiltinType::Int(BuiltinInt::Isize)),
         (name![i8],    BuiltinType::Int(BuiltinInt::I8)),
         (name![i16],   BuiltinType::Int(BuiltinInt::I16)),
         (name![i32],   BuiltinType::Int(BuiltinInt::I32)),
         (name![i64],   BuiltinType::Int(BuiltinInt::I64)),
         (name![i128],  BuiltinType::Int(BuiltinInt::I128)),
 
-        (name![usize], BuiltinType::Int(BuiltinInt::USIZE)),
-        (name![u8],    BuiltinType::Int(BuiltinInt::U8)),
-        (name![u16],   BuiltinType::Int(BuiltinInt::U16)),
-        (name![u32],   BuiltinType::Int(BuiltinInt::U32)),
-        (name![u64],   BuiltinType::Int(BuiltinInt::U64)),
-        (name![u128],  BuiltinType::Int(BuiltinInt::U128)),
+        (name![usize], BuiltinType::Uint(BuiltinUint::Usize)),
+        (name![u8],    BuiltinType::Uint(BuiltinUint::U8)),
+        (name![u16],   BuiltinType::Uint(BuiltinUint::U16)),
+        (name![u32],   BuiltinType::Uint(BuiltinUint::U32)),
+        (name![u64],   BuiltinType::Uint(BuiltinUint::U64)),
+        (name![u128],  BuiltinType::Uint(BuiltinUint::U128)),
 
         (name![f32], BuiltinType::Float(BuiltinFloat::F32)),
         (name![f64], BuiltinType::Float(BuiltinFloat::F64)),
@@ -81,24 +76,25 @@ impl AsName for BuiltinType {
             BuiltinType::Char => name![char],
             BuiltinType::Bool => name![bool],
             BuiltinType::Str => name![str],
-            BuiltinType::Int(BuiltinInt { signedness, bitness }) => match (signedness, bitness) {
-                (Signedness::Signed, IntBitness::Xsize) => name![isize],
-                (Signedness::Signed, IntBitness::X8) => name![i8],
-                (Signedness::Signed, IntBitness::X16) => name![i16],
-                (Signedness::Signed, IntBitness::X32) => name![i32],
-                (Signedness::Signed, IntBitness::X64) => name![i64],
-                (Signedness::Signed, IntBitness::X128) => name![i128],
-
-                (Signedness::Unsigned, IntBitness::Xsize) => name![usize],
-                (Signedness::Unsigned, IntBitness::X8) => name![u8],
-                (Signedness::Unsigned, IntBitness::X16) => name![u16],
-                (Signedness::Unsigned, IntBitness::X32) => name![u32],
-                (Signedness::Unsigned, IntBitness::X64) => name![u64],
-                (Signedness::Unsigned, IntBitness::X128) => name![u128],
+            BuiltinType::Int(it) => match it {
+                BuiltinInt::Isize => name![isize],
+                BuiltinInt::I8 => name![i8],
+                BuiltinInt::I16 => name![i16],
+                BuiltinInt::I32 => name![i32],
+                BuiltinInt::I64 => name![i64],
+                BuiltinInt::I128 => name![i128],
+            },
+            BuiltinType::Uint(it) => match it {
+                BuiltinUint::Usize => name![usize],
+                BuiltinUint::U8 => name![u8],
+                BuiltinUint::U16 => name![u16],
+                BuiltinUint::U32 => name![u32],
+                BuiltinUint::U64 => name![u64],
+                BuiltinUint::U128 => name![u128],
             },
-            BuiltinType::Float(BuiltinFloat { bitness }) => match bitness {
-                FloatBitness::X32 => name![f32],
-                FloatBitness::X64 => name![f64],
+            BuiltinType::Float(it) => match it {
+                BuiltinFloat::F32 => name![f32],
+                BuiltinFloat::F64 => name![f64],
             },
         }
     }
@@ -113,31 +109,26 @@ impl fmt::Display for BuiltinType {
 
 #[rustfmt::skip]
 impl BuiltinInt {
-    pub const ISIZE: BuiltinInt = BuiltinInt { signedness: Signedness::Signed, bitness: IntBitness::Xsize   };
-    pub const I8   : BuiltinInt = BuiltinInt { signedness: Signedness::Signed, bitness: IntBitness::X8      };
-    pub const I16  : BuiltinInt = BuiltinInt { signedness: Signedness::Signed, bitness: IntBitness::X16     };
-    pub const I32  : BuiltinInt = BuiltinInt { signedness: Signedness::Signed, bitness: IntBitness::X32     };
-    pub const I64  : BuiltinInt = BuiltinInt { signedness: Signedness::Signed, bitness: IntBitness::X64     };
-    pub const I128 : BuiltinInt = BuiltinInt { signedness: Signedness::Signed, bitness: IntBitness::X128    };
-
-    pub const USIZE: BuiltinInt = BuiltinInt { signedness: Signedness::Unsigned, bitness: IntBitness::Xsize };
-    pub const U8   : BuiltinInt = BuiltinInt { signedness: Signedness::Unsigned, bitness: IntBitness::X8    };
-    pub const U16  : BuiltinInt = BuiltinInt { signedness: Signedness::Unsigned, bitness: IntBitness::X16   };
-    pub const U32  : BuiltinInt = BuiltinInt { signedness: Signedness::Unsigned, bitness: IntBitness::X32   };
-    pub const U64  : BuiltinInt = BuiltinInt { signedness: Signedness::Unsigned, bitness: IntBitness::X64   };
-    pub const U128 : BuiltinInt = BuiltinInt { signedness: Signedness::Unsigned, bitness: IntBitness::X128  };
-
-
     pub fn from_suffix(suffix: &str) -> Option<BuiltinInt> {
         let res = match suffix {
-            "isize" => Self::ISIZE,
+            "isize" => Self::Isize,
             "i8"    => Self::I8,
             "i16"   => Self::I16,
             "i32"   => Self::I32,
             "i64"   => Self::I64,
             "i128"  => Self::I128,
 
-            "usize" => Self::USIZE,
+            _ => return None,
+        };
+        Some(res)
+    }
+}
+
+#[rustfmt::skip]
+impl BuiltinUint {
+    pub fn from_suffix(suffix: &str) -> Option<BuiltinUint> {
+        let res = match suffix {
+            "usize" => Self::Usize,
             "u8"    => Self::U8,
             "u16"   => Self::U16,
             "u32"   => Self::U32,
@@ -152,9 +143,6 @@ impl BuiltinInt {
 
 #[rustfmt::skip]
 impl BuiltinFloat {
-    pub const F32: BuiltinFloat = BuiltinFloat { bitness: FloatBitness::X32 };
-    pub const F64: BuiltinFloat = BuiltinFloat { bitness: FloatBitness::X64 };
-
     pub fn from_suffix(suffix: &str) -> Option<BuiltinFloat> {
         let res = match suffix {
             "f32" => BuiltinFloat::F32,
diff --git a/crates/hir_def/src/diagnostics.rs b/crates/hir_def/src/diagnostics.rs
index ab3f059ce..ac7474f63 100644
--- a/crates/hir_def/src/diagnostics.rs
+++ b/crates/hir_def/src/diagnostics.rs
@@ -95,6 +95,34 @@ impl Diagnostic for UnresolvedImport {
     }
 }
 
+// Diagnostic: unresolved-macro-call
+//
+// This diagnostic is triggered if rust-analyzer is unable to resolove path to a
+// macro in a macro invocation.
+#[derive(Debug)]
+pub struct UnresolvedMacroCall {
+    pub file: HirFileId,
+    pub node: AstPtr<ast::MacroCall>,
+}
+
+impl Diagnostic for UnresolvedMacroCall {
+    fn code(&self) -> DiagnosticCode {
+        DiagnosticCode("unresolved-macro-call")
+    }
+    fn message(&self) -> String {
+        "unresolved macro call".to_string()
+    }
+    fn display_source(&self) -> InFile<SyntaxNodePtr> {
+        InFile::new(self.file, self.node.clone().into())
+    }
+    fn as_any(&self) -> &(dyn Any + Send + 'static) {
+        self
+    }
+    fn is_experimental(&self) -> bool {
+        true
+    }
+}
+
 // Diagnostic: inactive-code
 //
 // This diagnostic is shown for code with inactive `#[cfg]` attributes.
diff --git a/crates/hir_def/src/expr.rs b/crates/hir_def/src/expr.rs
index 4d72eaeaf..24be93773 100644
--- a/crates/hir_def/src/expr.rs
+++ b/crates/hir_def/src/expr.rs
@@ -17,7 +17,7 @@ use la_arena::{Idx, RawIdx};
 use syntax::ast::RangeOp;
 
 use crate::{
-    builtin_type::{BuiltinFloat, BuiltinInt},
+    builtin_type::{BuiltinFloat, BuiltinInt, BuiltinUint},
     path::{GenericArgs, Path},
     type_ref::{Mutability, Rawness, TypeRef},
     BlockId,
@@ -43,6 +43,7 @@ pub enum Literal {
     Char(char),
     Bool(bool),
     Int(u64, Option<BuiltinInt>),
+    Uint(u64, Option<BuiltinUint>),
     Float(u64, Option<BuiltinFloat>), // FIXME: f64 is not Eq
 }
 
diff --git a/crates/hir_def/src/find_path.rs b/crates/hir_def/src/find_path.rs
index 5e2a711b8..3e19a7702 100644
--- a/crates/hir_def/src/find_path.rs
+++ b/crates/hir_def/src/find_path.rs
@@ -1,5 +1,7 @@
 //! An algorithm to find a path to refer to a certain item.
 
+use std::iter;
+
 use hir_expand::name::{known, AsName, Name};
 use rustc_hash::FxHashSet;
 use test_utils::mark;
@@ -95,7 +97,7 @@ fn find_path_inner(
     item: ItemInNs,
     from: ModuleId,
     max_len: usize,
-    prefixed: Option<PrefixKind>,
+    mut prefixed: Option<PrefixKind>,
 ) -> Option<ModPath> {
     if max_len == 0 {
         return None;
@@ -114,8 +116,9 @@ fn find_path_inner(
     }
 
     // - if the item is the crate root, return `crate`
-    let root = def_map.module_id(def_map.root());
+    let root = def_map.crate_root(db);
     if item == ItemInNs::Types(ModuleDefId::ModuleId(root)) && def_map.block_id().is_none() {
+        // FIXME: the `block_id()` check should be unnecessary, but affects the result
         return Some(ModPath::from_segments(PathKind::Crate, Vec::new()));
     }
 
@@ -165,7 +168,7 @@ fn find_path_inner(
 
     // - otherwise, look for modules containing (reexporting) it and import it from one of those
 
-    let crate_root = def_map.module_id(def_map.root());
+    let crate_root = def_map.crate_root(db);
     let crate_attrs = db.attrs(crate_root.into());
     let prefer_no_std = crate_attrs.by_key("no_std").exists();
     let mut best_path = None;
@@ -228,12 +231,16 @@ fn find_path_inner(
         }
     }
 
-    if let Some(mut prefix) = prefixed.map(PrefixKind::prefix) {
-        if matches!(prefix, PathKind::Crate | PathKind::Super(0)) && def_map.block_id().is_some() {
-            // Inner items cannot be referred to via `crate::` or `self::` paths.
-            prefix = PathKind::Plain;
+    // If the item is declared inside a block expression, don't use a prefix, as we don't handle
+    // that correctly (FIXME).
+    if let Some(item_module) = item.as_module_def_id().and_then(|did| did.module(db)) {
+        if item_module.def_map(db).block_id().is_some() && prefixed.is_some() {
+            mark::hit!(prefixed_in_block_expression);
+            prefixed = Some(PrefixKind::Plain);
         }
+    }
 
+    if let Some(prefix) = prefixed.map(PrefixKind::prefix) {
         best_path.or_else(|| {
             scope_name.map(|scope_name| ModPath::from_segments(prefix, vec![scope_name]))
         })
@@ -285,12 +292,12 @@ fn find_local_import_locations(
     let data = &def_map[from.local_id];
     let mut worklist =
         data.children.values().map(|child| def_map.module_id(*child)).collect::<Vec<_>>();
-    let mut parent = data.parent;
-    while let Some(p) = parent {
-        worklist.push(def_map.module_id(p));
-        parent = def_map[p].parent;
+    for ancestor in iter::successors(from.containing_module(db), |m| m.containing_module(db)) {
+        worklist.push(ancestor);
     }
 
+    let def_map = def_map.crate_root(db).def_map(db);
+
     let mut seen: FxHashSet<_> = FxHashSet::default();
 
     let mut locations = Vec::new();
@@ -301,7 +308,14 @@ fn find_local_import_locations(
 
         let ext_def_map;
         let data = if module.krate == from.krate {
-            &def_map[module.local_id]
+            if module.block.is_some() {
+                // Re-query the block's DefMap
+                ext_def_map = module.def_map(db);
+                &ext_def_map[module.local_id]
+            } else {
+                // Reuse the root DefMap
+                &def_map[module.local_id]
+            }
         } else {
             // The crate might reexport a module defined in another crate.
             ext_def_map = module.def_map(db);
@@ -828,6 +842,7 @@ mod tests {
 
     #[test]
     fn inner_items_from_inner_module() {
+        mark::check!(prefixed_in_block_expression);
         check_found_path(
             r#"
             fn main() {
@@ -869,4 +884,24 @@ mod tests {
             "super::Struct",
         );
     }
+
+    #[test]
+    fn outer_items_with_inner_items_present() {
+        check_found_path(
+            r#"
+            mod module {
+                pub struct CompleteMe;
+            }
+
+            fn main() {
+                fn inner() {}
+                $0
+            }
+            "#,
+            "module::CompleteMe",
+            "module::CompleteMe",
+            "crate::module::CompleteMe",
+            "self::module::CompleteMe",
+        )
+    }
 }
diff --git a/crates/hir_def/src/item_scope.rs b/crates/hir_def/src/item_scope.rs
index ee46c3330..4e5daa2ff 100644
--- a/crates/hir_def/src/item_scope.rs
+++ b/crates/hir_def/src/item_scope.rs
@@ -12,8 +12,8 @@ use stdx::format_to;
 use test_utils::mark;
 
 use crate::{
-    db::DefDatabase, per_ns::PerNs, visibility::Visibility, AdtId, BuiltinType, HasModule, ImplId,
-    LocalModuleId, Lookup, MacroDefId, ModuleDefId, ModuleId, TraitId,
+    db::DefDatabase, per_ns::PerNs, visibility::Visibility, AdtId, BuiltinType, ImplId,
+    LocalModuleId, MacroDefId, ModuleDefId, ModuleId, TraitId,
 };
 
 #[derive(Copy, Clone)]
@@ -375,19 +375,9 @@ impl ItemInNs {
 
     /// Returns the crate defining this item (or `None` if `self` is built-in).
     pub fn krate(&self, db: &dyn DefDatabase) -> Option<CrateId> {
-        Some(match self {
-            ItemInNs::Types(did) | ItemInNs::Values(did) => match did {
-                ModuleDefId::ModuleId(id) => id.krate,
-                ModuleDefId::FunctionId(id) => id.lookup(db).module(db).krate,
-                ModuleDefId::AdtId(id) => id.module(db).krate,
-                ModuleDefId::EnumVariantId(id) => id.parent.lookup(db).container.module(db).krate,
-                ModuleDefId::ConstId(id) => id.lookup(db).container.module(db).krate,
-                ModuleDefId::StaticId(id) => id.lookup(db).container.module(db).krate,
-                ModuleDefId::TraitId(id) => id.lookup(db).container.module(db).krate,
-                ModuleDefId::TypeAliasId(id) => id.lookup(db).module(db).krate,
-                ModuleDefId::BuiltinType(_) => return None,
-            },
-            ItemInNs::Macros(id) => return Some(id.krate),
-        })
+        match self {
+            ItemInNs::Types(did) | ItemInNs::Values(did) => did.module(db).map(|m| m.krate),
+            ItemInNs::Macros(id) => Some(id.krate),
+        }
     }
 }
diff --git a/crates/hir_def/src/lib.rs b/crates/hir_def/src/lib.rs
index b50923747..4498d94bb 100644
--- a/crates/hir_def/src/lib.rs
+++ b/crates/hir_def/src/lib.rs
@@ -57,8 +57,10 @@ use std::{
 
 use base_db::{impl_intern_key, salsa, CrateId};
 use hir_expand::{
-    ast_id_map::FileAstId, eager::expand_eager_macro, hygiene::Hygiene, AstId, HirFileId, InFile,
-    MacroCallId, MacroCallKind, MacroDefId, MacroDefKind,
+    ast_id_map::FileAstId,
+    eager::{expand_eager_macro, ErrorEmitted},
+    hygiene::Hygiene,
+    AstId, HirFileId, InFile, MacroCallId, MacroCallKind, MacroDefId, MacroDefKind,
 };
 use la_arena::Idx;
 use nameres::DefMap;
@@ -95,6 +97,10 @@ impl ModuleId {
     pub fn krate(&self) -> CrateId {
         self.krate
     }
+
+    pub fn containing_module(&self, db: &dyn db::DefDatabase) -> Option<ModuleId> {
+        self.def_map(db).containing_module(self.local_id)
+    }
 }
 
 /// An ID of a module, **local** to a specific crate
@@ -527,6 +533,25 @@ impl HasModule for StaticLoc {
     }
 }
 
+impl ModuleDefId {
+    /// Returns the module containing `self` (or `self`, if `self` is itself a module).
+    ///
+    /// Returns `None` if `self` refers to a primitive type.
+    pub fn module(&self, db: &dyn db::DefDatabase) -> Option<ModuleId> {
+        Some(match self {
+            ModuleDefId::ModuleId(id) => *id,
+            ModuleDefId::FunctionId(id) => id.lookup(db).module(db),
+            ModuleDefId::AdtId(id) => id.module(db),
+            ModuleDefId::EnumVariantId(id) => id.parent.lookup(db).container.module(db),
+            ModuleDefId::ConstId(id) => id.lookup(db).container.module(db),
+            ModuleDefId::StaticId(id) => id.lookup(db).container.module(db),
+            ModuleDefId::TraitId(id) => id.lookup(db).container.module(db),
+            ModuleDefId::TypeAliasId(id) => id.lookup(db).module(db),
+            ModuleDefId::BuiltinType(_) => return None,
+        })
+    }
+}
+
 impl AttrDefId {
     pub fn krate(&self, db: &dyn db::DefDatabase) -> CrateId {
         match self {
@@ -592,8 +617,15 @@ impl AsMacroCall for InFile<&ast::MacroCall> {
             error_sink(mbe::ExpandError::Other("malformed macro invocation".into()));
         }
 
-        AstIdWithPath::new(ast_id.file_id, ast_id.value, path?)
-            .as_call_id_with_errors(db, krate, resolver, error_sink)
+        macro_call_as_call_id(
+            &AstIdWithPath::new(ast_id.file_id, ast_id.value, path?),
+            db,
+            krate,
+            resolver,
+            error_sink,
+        )
+        .ok()?
+        .ok()
     }
 }
 
@@ -610,61 +642,50 @@ impl<T: ast::AstNode> AstIdWithPath<T> {
     }
 }
 
-impl AsMacroCall for AstIdWithPath<ast::MacroCall> {
-    fn as_call_id_with_errors(
-        &self,
-        db: &dyn db::DefDatabase,
-        krate: CrateId,
-        resolver: impl Fn(path::ModPath) -> Option<MacroDefId>,
-        error_sink: &mut dyn FnMut(mbe::ExpandError),
-    ) -> Option<MacroCallId> {
-        let def: MacroDefId = resolver(self.path.clone()).or_else(|| {
-            error_sink(mbe::ExpandError::Other(format!("could not resolve macro `{}`", self.path)));
-            None
-        })?;
-
-        if let MacroDefKind::BuiltInEager(_) = def.kind {
-            let macro_call = InFile::new(self.ast_id.file_id, self.ast_id.to_node(db.upcast()));
-            let hygiene = Hygiene::new(db.upcast(), self.ast_id.file_id);
-
-            Some(
-                expand_eager_macro(
-                    db.upcast(),
-                    krate,
-                    macro_call,
-                    def,
-                    &|path: ast::Path| resolver(path::ModPath::from_src(path, &hygiene)?),
-                    error_sink,
-                )
-                .ok()?
-                .into(),
-            )
-        } else {
-            Some(def.as_lazy_macro(db.upcast(), krate, MacroCallKind::FnLike(self.ast_id)).into())
-        }
-    }
+struct UnresolvedMacro;
+
+fn macro_call_as_call_id(
+    call: &AstIdWithPath<ast::MacroCall>,
+    db: &dyn db::DefDatabase,
+    krate: CrateId,
+    resolver: impl Fn(path::ModPath) -> Option<MacroDefId>,
+    error_sink: &mut dyn FnMut(mbe::ExpandError),
+) -> Result<Result<MacroCallId, ErrorEmitted>, UnresolvedMacro> {
+    let def: MacroDefId = resolver(call.path.clone()).ok_or(UnresolvedMacro)?;
+
+    let res = if let MacroDefKind::BuiltInEager(_) = def.kind {
+        let macro_call = InFile::new(call.ast_id.file_id, call.ast_id.to_node(db.upcast()));
+        let hygiene = Hygiene::new(db.upcast(), call.ast_id.file_id);
+
+        expand_eager_macro(
+            db.upcast(),
+            krate,
+            macro_call,
+            def,
+            &|path: ast::Path| resolver(path::ModPath::from_src(path, &hygiene)?),
+            error_sink,
+        )
+        .map(MacroCallId::from)
+    } else {
+        Ok(def.as_lazy_macro(db.upcast(), krate, MacroCallKind::FnLike(call.ast_id)).into())
+    };
+    Ok(res)
 }
 
-impl AsMacroCall for AstIdWithPath<ast::Item> {
-    fn as_call_id_with_errors(
-        &self,
-        db: &dyn db::DefDatabase,
-        krate: CrateId,
-        resolver: impl Fn(path::ModPath) -> Option<MacroDefId>,
-        error_sink: &mut dyn FnMut(mbe::ExpandError),
-    ) -> Option<MacroCallId> {
-        let def: MacroDefId = resolver(self.path.clone()).or_else(|| {
-            error_sink(mbe::ExpandError::Other(format!("could not resolve macro `{}`", self.path)));
-            None
-        })?;
-
-        Some(
-            def.as_lazy_macro(
-                db.upcast(),
-                krate,
-                MacroCallKind::Attr(self.ast_id, self.path.segments().last()?.to_string()),
-            )
-            .into(),
+fn item_attr_as_call_id(
+    item_attr: &AstIdWithPath<ast::Item>,
+    db: &dyn db::DefDatabase,
+    krate: CrateId,
+    resolver: impl Fn(path::ModPath) -> Option<MacroDefId>,
+) -> Result<MacroCallId, UnresolvedMacro> {
+    let def: MacroDefId = resolver(item_attr.path.clone()).ok_or(UnresolvedMacro)?;
+    let last_segment = item_attr.path.segments().last().ok_or(UnresolvedMacro)?;
+    let res = def
+        .as_lazy_macro(
+            db.upcast(),
+            krate,
+            MacroCallKind::Attr(item_attr.ast_id, last_segment.to_string()),
         )
-    }
+        .into();
+    Ok(res)
 }
diff --git a/crates/hir_def/src/nameres.rs b/crates/hir_def/src/nameres.rs
index f92232eb3..003d668ca 100644
--- a/crates/hir_def/src/nameres.rs
+++ b/crates/hir_def/src/nameres.rs
@@ -343,6 +343,18 @@ impl DefMap {
         Some(self.block?.parent)
     }
 
+    /// Returns the module containing `local_mod`, either the parent `mod`, or the module containing
+    /// the block, if `self` corresponds to a block expression.
+    pub fn containing_module(&self, local_mod: LocalModuleId) -> Option<ModuleId> {
+        match &self[local_mod].parent {
+            Some(parent) => Some(self.module_id(*parent)),
+            None => match &self.block {
+                Some(block) => Some(block.parent),
+                None => None,
+            },
+        }
+    }
+
     // FIXME: this can use some more human-readable format (ideally, an IR
     // even), as this should be a great debugging aid.
     pub fn dump(&self, db: &dyn DefDatabase) -> String {
@@ -417,6 +429,8 @@ mod diagnostics {
 
         UnresolvedProcMacro { ast: MacroCallKind },
 
+        UnresolvedMacroCall { ast: AstId<ast::MacroCall> },
+
         MacroError { ast: MacroCallKind, message: String },
     }
 
@@ -477,6 +491,13 @@ mod diagnostics {
             Self { in_module: container, kind: DiagnosticKind::MacroError { ast, message } }
         }
 
+        pub(super) fn unresolved_macro_call(
+            container: LocalModuleId,
+            ast: AstId<ast::MacroCall>,
+        ) -> Self {
+            Self { in_module: container, kind: DiagnosticKind::UnresolvedMacroCall { ast } }
+        }
+
         pub(super) fn add_to(
             &self,
             db: &dyn DefDatabase,
@@ -589,6 +610,11 @@ mod diagnostics {
                     });
                 }
 
+                DiagnosticKind::UnresolvedMacroCall { ast } => {
+                    let node = ast.to_node(db.upcast());
+                    sink.push(UnresolvedMacroCall { file: ast.file_id, node: AstPtr::new(&node) });
+                }
+
                 DiagnosticKind::MacroError { ast, message } => {
                     let (file, ast) = match ast {
                         MacroCallKind::FnLike(ast) => {
diff --git a/crates/hir_def/src/nameres/collector.rs b/crates/hir_def/src/nameres/collector.rs
index 9996a0807..e51d89b43 100644
--- a/crates/hir_def/src/nameres/collector.rs
+++ b/crates/hir_def/src/nameres/collector.rs
@@ -13,7 +13,7 @@ use hir_expand::{
     builtin_macro::find_builtin_macro,
     name::{AsName, Name},
     proc_macro::ProcMacroExpander,
-    HirFileId, MacroCallId, MacroCallKind, MacroDefId, MacroDefKind,
+    HirFileId, MacroCallId, MacroDefId, MacroDefKind,
 };
 use hir_expand::{InFile, MacroCallLoc};
 use rustc_hash::{FxHashMap, FxHashSet};
@@ -24,11 +24,13 @@ use tt::{Leaf, TokenTree};
 use crate::{
     attr::Attrs,
     db::DefDatabase,
+    item_attr_as_call_id,
     item_scope::{ImportType, PerNsGlobImports},
     item_tree::{
         self, FileItemTreeId, ItemTree, ItemTreeId, MacroCall, MacroRules, Mod, ModItem, ModKind,
         StructDefKind,
     },
+    macro_call_as_call_id,
     nameres::{
         diagnostics::DefDiagnostic, mod_resolution::ModDir, path_resolution::ReachedFixedPoint,
         BuiltinShadowMode, DefMap, ModuleData, ModuleOrigin, ResolveMode,
@@ -36,9 +38,9 @@ use crate::{
     path::{ImportAlias, ModPath, PathKind},
     per_ns::PerNs,
     visibility::{RawVisibility, Visibility},
-    AdtId, AsMacroCall, AstId, AstIdWithPath, ConstLoc, ContainerId, EnumLoc, EnumVariantId,
-    FunctionLoc, ImplLoc, Intern, LocalModuleId, ModuleDefId, StaticLoc, StructLoc, TraitLoc,
-    TypeAliasLoc, UnionLoc,
+    AdtId, AstId, AstIdWithPath, ConstLoc, ContainerId, EnumLoc, EnumVariantId, FunctionLoc,
+    ImplLoc, Intern, LocalModuleId, ModuleDefId, StaticLoc, StructLoc, TraitLoc, TypeAliasLoc,
+    UnionLoc, UnresolvedMacro,
 };
 
 const GLOB_RECURSION_LIMIT: usize = 100;
@@ -790,8 +792,11 @@ impl DefCollector<'_> {
                 return false;
             }
 
-            if let Some(call_id) =
-                directive.ast_id.as_call_id(self.db, self.def_map.krate, |path| {
+            match macro_call_as_call_id(
+                &directive.ast_id,
+                self.db,
+                self.def_map.krate,
+                |path| {
                     let resolved_res = self.def_map.resolve_path_fp_with_macro(
                         self.db,
                         ResolveMode::Other,
@@ -800,24 +805,29 @@ impl DefCollector<'_> {
                         BuiltinShadowMode::Module,
                     );
                     resolved_res.resolved_def.take_macros()
-                })
-            {
-                resolved.push((directive.module_id, call_id, directive.depth));
-                res = ReachedFixedPoint::No;
-                return false;
+                },
+                &mut |_err| (),
+            ) {
+                Ok(Ok(call_id)) => {
+                    resolved.push((directive.module_id, call_id, directive.depth));
+                    res = ReachedFixedPoint::No;
+                    return false;
+                }
+                Err(UnresolvedMacro) | Ok(Err(_)) => {}
             }
 
             true
         });
         attribute_macros.retain(|directive| {
-            if let Some(call_id) =
-                directive.ast_id.as_call_id(self.db, self.def_map.krate, |path| {
-                    self.resolve_attribute_macro(&directive, &path)
-                })
-            {
-                resolved.push((directive.module_id, call_id, 0));
-                res = ReachedFixedPoint::No;
-                return false;
+            match item_attr_as_call_id(&directive.ast_id, self.db, self.def_map.krate, |path| {
+                self.resolve_attribute_macro(&directive, &path)
+            }) {
+                Ok(call_id) => {
+                    resolved.push((directive.module_id, call_id, 0));
+                    res = ReachedFixedPoint::No;
+                    return false;
+                }
+                Err(UnresolvedMacro) => (),
             }
 
             true
@@ -902,7 +912,8 @@ impl DefCollector<'_> {
 
         for directive in &self.unexpanded_macros {
             let mut error = None;
-            directive.ast_id.as_call_id_with_errors(
+            match macro_call_as_call_id(
+                &directive.ast_id,
                 self.db,
                 self.def_map.krate,
                 |path| {
@@ -918,15 +929,15 @@ impl DefCollector<'_> {
                 &mut |e| {
                     error.get_or_insert(e);
                 },
-            );
-
-            if let Some(err) = error {
-                self.def_map.diagnostics.push(DefDiagnostic::macro_error(
-                    directive.module_id,
-                    MacroCallKind::FnLike(directive.ast_id.ast_id),
-                    err.to_string(),
-                ));
-            }
+            ) {
+                Ok(_) => (),
+                Err(UnresolvedMacro) => {
+                    self.def_map.diagnostics.push(DefDiagnostic::unresolved_macro_call(
+                        directive.module_id,
+                        directive.ast_id.ast_id,
+                    ));
+                }
+            };
         }
 
         // Emit diagnostics for all remaining unresolved imports.
@@ -1446,8 +1457,11 @@ impl ModCollector<'_, '_> {
         let mut ast_id = AstIdWithPath::new(self.file_id, mac.ast_id, mac.path.clone());
 
         // Case 1: try to resolve in legacy scope and expand macro_rules
-        if let Some(macro_call_id) =
-            ast_id.as_call_id(self.def_collector.db, self.def_collector.def_map.krate, |path| {
+        if let Ok(Ok(macro_call_id)) = macro_call_as_call_id(
+            &ast_id,
+            self.def_collector.db,
+            self.def_collector.def_map.krate,
+            |path| {
                 path.as_ident().and_then(|name| {
                     self.def_collector.def_map.with_ancestor_maps(
                         self.def_collector.db,
@@ -1455,8 +1469,9 @@ impl ModCollector<'_, '_> {
                         &mut |map, module| map[module].scope.get_legacy_macro(&name),
                     )
                 })
-            })
-        {
+            },
+            &mut |_err| (),
+        ) {
             self.def_collector.unexpanded_macros.push(MacroDirective {
                 module_id: self.module_id,
                 ast_id,
diff --git a/crates/hir_def/src/nameres/path_resolution.rs b/crates/hir_def/src/nameres/path_resolution.rs
index fdcdc23ae..dd1db0094 100644
--- a/crates/hir_def/src/nameres/path_resolution.rs
+++ b/crates/hir_def/src/nameres/path_resolution.rs
@@ -77,7 +77,7 @@ impl DefMap {
         original_module: LocalModuleId,
         visibility: &RawVisibility,
     ) -> Option<Visibility> {
-        match visibility {
+        let mut vis = match visibility {
             RawVisibility::Module(path) => {
                 let (result, remaining) =
                     self.resolve_path(db, original_module, &path, BuiltinShadowMode::Module);
@@ -86,15 +86,28 @@ impl DefMap {
                 }
                 let types = result.take_types()?;
                 match types {
-                    ModuleDefId::ModuleId(m) => Some(Visibility::Module(m)),
+                    ModuleDefId::ModuleId(m) => Visibility::Module(m),
                     _ => {
                         // error: visibility needs to refer to module
-                        None
+                        return None;
                     }
                 }
             }
-            RawVisibility::Public => Some(Visibility::Public),
+            RawVisibility::Public => Visibility::Public,
+        };
+
+        // In block expressions, `self` normally refers to the containing non-block module, and
+        // `super` to its parent (etc.). However, visibilities must only refer to a module in the
+        // DefMap they're written in, so we restrict them when that happens.
+        if let Visibility::Module(m) = vis {
+            if self.block_id() != m.block {
+                mark::hit!(adjust_vis_in_block_def_map);
+                vis = Visibility::Module(self.module_id(self.root()));
+                log::debug!("visibility {:?} points outside DefMap, adjusting to {:?}", m, vis);
+            }
         }
+
+        Some(vis)
     }
 
     // Returns Yes if we are sure that additions to `ItemMap` wouldn't change
diff --git a/crates/hir_def/src/path/lower.rs b/crates/hir_def/src/path/lower.rs
index a469546c1..505493a74 100644
--- a/crates/hir_def/src/path/lower.rs
+++ b/crates/hir_def/src/path/lower.rs
@@ -101,8 +101,12 @@ pub(super) fn lower_path(mut path: ast::Path, hygiene: &Hygiene) -> Option<Path>
                 break;
             }
             ast::PathSegmentKind::SelfKw => {
-                kind = PathKind::Super(0);
-                break;
+                // don't break out if `self` is the last segment of a path, this mean we got an
+                // use tree like `foo::{self}` which we want to resolve as `foo`
+                if !segments.is_empty() {
+                    kind = PathKind::Super(0);
+                    break;
+                }
             }
             ast::PathSegmentKind::SuperKw => {
                 let nested_super_count = if let PathKind::Super(n) = kind { n } else { 0 };
@@ -117,6 +121,11 @@ pub(super) fn lower_path(mut path: ast::Path, hygiene: &Hygiene) -> Option<Path>
     segments.reverse();
     generic_args.reverse();
 
+    if segments.is_empty() && kind == PathKind::Plain && type_anchor.is_none() {
+        // plain empty paths don't exist, this means we got a single `self` segment as our path
+        kind = PathKind::Super(0);
+    }
+
     // handle local_inner_macros :
     // Basically, even in rustc it is quite hacky:
     // https://github.com/rust-lang/rust/blob/614f273e9388ddd7804d5cbc80b8865068a3744e/src/librustc_resolve/macros.rs#L456