add ability to get strcut field source

crates/ra_hir/src/adt.rs

@@ -11,7 +11,7 @@ use ra_syntax::{
 
 use crate::{
     Name, AsName, Struct, Enum, EnumVariant, Crate,
-    HirDatabase, HirFileId,
+    HirDatabase, HirFileId, StructField, FieldSource,
     type_ref::TypeRef,
 };
 
@@ -150,7 +150,7 @@ impl VariantData {
 impl VariantData {
     fn new(flavor: StructFlavor) -> Self {
         let inner = match flavor {
-            StructFlavor::Tuple(fl) => {
+            ast::StructFlavor::Tuple(fl) => {
                 let fields = fl
                     .fields()
                     .enumerate()
@@ -161,7 +161,7 @@ impl VariantData {
                     .collect();
                 VariantDataInner::Tuple(fields)
             }
-            StructFlavor::Named(fl) => {
+            ast::StructFlavor::Named(fl) => {
                 let fields = fl
                     .fields()
                     .map(|fd| StructFieldData {
@@ -171,8 +171,70 @@ impl VariantData {
                     .collect();
                 VariantDataInner::Struct(fields)
             }
-            StructFlavor::Unit => VariantDataInner::Unit,
+            ast::StructFlavor::Unit => VariantDataInner::Unit,
         };
         VariantData(inner)
     }
 }
+
+#[derive(Clone, Copy, Debug, PartialEq, Eq, Hash)]
+pub enum VariantDef {
+    Struct(Struct),
+    EnumVariant(EnumVariant),
+}
+impl_froms!(VariantDef: Struct, EnumVariant);
+
+impl VariantDef {
+    pub(crate) fn field(self, db: &impl HirDatabase, name: &Name) -> Option<StructField> {
+        match self {
+            VariantDef::Struct(it) => it.field(db, name),
+            VariantDef::EnumVariant(it) => it.field(db, name),
+        }
+    }
+    pub(crate) fn variant_data(self, db: &impl HirDatabase) -> Arc<VariantData> {
+        match self {
+            VariantDef::Struct(it) => it.variant_data(db),
+            VariantDef::EnumVariant(it) => it.variant_data(db),
+        }
+    }
+}
+
+impl StructField {
+    pub(crate) fn source_impl(&self, db: &impl HirDatabase) -> (HirFileId, FieldSource) {
+        let var_data = self.parent.variant_data(db);
+        let fields = var_data.fields().unwrap();
+        let ss;
+        let es;
+        let (file_id, struct_flavor) = match self.parent {
+            VariantDef::Struct(s) => {
+                let (file_id, source) = s.source(db);
+                ss = source;
+                (file_id, ss.flavor())
+            }
+            VariantDef::EnumVariant(e) => {
+                let (file_id, source) = e.source(db);
+                es = source;
+                (file_id, es.flavor())
+            }
+        };
+
+        let field_sources = match struct_flavor {
+            ast::StructFlavor::Tuple(fl) => fl
+                .fields()
+                .map(|it| FieldSource::Pos(it.to_owned()))
+                .collect(),
+            ast::StructFlavor::Named(fl) => fl
+                .fields()
+                .map(|it| FieldSource::Named(it.to_owned()))
+                .collect(),
+            ast::StructFlavor::Unit => Vec::new(),
+        };
+        let field = field_sources
+            .into_iter()
+            .zip(fields.iter())
+            .find(|(_syntax, (id, _))| *id == self.id)
+            .unwrap()
+            .0;
+        (file_id, field)
+    }
+}

crates/ra_hir/src/code_model_api.rs

@@ -10,8 +10,8 @@ use crate::{
     nameres::{ModuleScope, lower::ImportId},
     db::HirDatabase,
     expr::BodySyntaxMapping,
-    ty::{InferenceResult, VariantDef},
-    adt::{EnumVariantId, StructFieldId},
+    ty::InferenceResult,
+    adt::{EnumVariantId, StructFieldId, VariantDef},
     generics::GenericParams,
     docs::{Documentation, Docs, docs_from_ast},
     module_tree::ModuleId,
@@ -179,10 +179,16 @@ impl Module {
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
 pub struct StructField {
-    parent: VariantDef,
+    pub(crate) parent: VariantDef,
     pub(crate) id: StructFieldId,
 }
 
+#[derive(Debug)]
+pub enum FieldSource {
+    Named(TreeArc<ast::NamedFieldDef>),
+    Pos(TreeArc<ast::PosField>),
+}
+
 impl StructField {
     pub fn name(&self, db: &impl HirDatabase) -> Name {
         self.parent.variant_data(db).fields().unwrap()[self.id]
@@ -190,6 +196,10 @@ impl StructField {
             .clone()
     }
 
+    pub fn source(&self, db: &impl HirDatabase) -> (HirFileId, FieldSource) {
+        self.source_impl(db)
+    }
+
     pub fn ty(&self, db: &impl HirDatabase) -> Ty {
         db.type_for_field(*self)
     }

crates/ra_hir/src/lib.rs

@@ -68,7 +68,7 @@ pub use self::code_model_api::{
     Module, ModuleDef, ModuleSource, Problem,
     Struct, Enum, EnumVariant,
     Function, FnSignature, ScopeEntryWithSyntax,
-    StructField,
+    StructField, FieldSource,
     Static, Const,
     Trait, Type,
 };

crates/ra_hir/src/ty.rs

@@ -38,7 +38,7 @@ use crate::{
     expr::{Body, Expr, BindingAnnotation, Literal, ExprId, Pat, PatId, UnaryOp, BinaryOp, Statement, FieldPat},
     generics::GenericParams,
     path::GenericArg,
-    adt::VariantData,
+    adt::VariantDef,
 };
 
 /// The ID of a type variable.
@@ -696,28 +696,6 @@ pub(super) fn type_for_def(db: &impl HirDatabase, def: TypableDef) -> Ty {
     }
 }
 
-#[derive(Clone, Copy, Debug, PartialEq, Eq, Hash)]
-pub enum VariantDef {
-    Struct(Struct),
-    EnumVariant(EnumVariant),
-}
-impl_froms!(VariantDef: Struct, EnumVariant);
-
-impl VariantDef {
-    pub(crate) fn field(self, db: &impl HirDatabase, name: &Name) -> Option<StructField> {
-        match self {
-            VariantDef::Struct(it) => it.field(db, name),
-            VariantDef::EnumVariant(it) => it.field(db, name),
-        }
-    }
-    pub(crate) fn variant_data(self, db: &impl HirDatabase) -> Arc<VariantData> {
-        match self {
-            VariantDef::Struct(it) => it.variant_data(db),
-            VariantDef::EnumVariant(it) => it.variant_data(db),
-        }
-    }
-}
-
 pub(super) fn type_for_field(db: &impl HirDatabase, field: StructField) -> Ty {
     let parent_def = field.parent_def(db);
     let (generics, module) = match parent_def {
@@ -744,6 +722,9 @@ impl InferenceResult {
     pub fn method_resolution(&self, expr: ExprId) -> Option<Function> {
         self.method_resolutions.get(&expr).map(|it| *it)
     }
+    pub fn field_resolution(&self, expr: ExprId) -> Option<StructField> {
+        self.field_resolutions.get(&expr).map(|it| *it)
+    }
 }
 
 impl Index<ExprId> for InferenceResult {

crates/ra_ide_api/src/goto_definition.rs

@@ -3,6 +3,7 @@ use ra_syntax::{
     AstNode, ast,
     algo::find_node_at_offset,
 };
+use test_utils::tested_by;
 
 use crate::{FilePosition, NavigationTarget, db::RootDatabase, RangeInfo};
 
@@ -60,6 +61,7 @@ pub(crate) fn reference_definition(
             .parent()
             .and_then(ast::MethodCallExpr::cast)
         {
+            tested_by!(goto_definition_works_for_methods);
             let infer_result = function.infer(db);
             let syntax_mapping = function.body_syntax_mapping(db);
             let expr = ast::Expr::cast(method_call.syntax()).unwrap();
@@ -70,6 +72,19 @@ pub(crate) fn reference_definition(
                 return Exact(NavigationTarget::from_function(db, func));
             };
         }
+        // It could also be a field access
+        if let Some(field_expr) = name_ref.syntax().parent().and_then(ast::FieldExpr::cast) {
+            tested_by!(goto_definition_works_for_fields);
+            let infer_result = function.infer(db);
+            let syntax_mapping = function.body_syntax_mapping(db);
+            let expr = ast::Expr::cast(field_expr.syntax()).unwrap();
+            if let Some(field) = syntax_mapping
+                .node_expr(expr)
+                .and_then(|it| infer_result.field_resolution(it))
+            {
+                return Exact(NavigationTarget::from_field(db, field));
+            };
+        }
     }
     // Then try module name resolution
     if let Some(module) = hir::source_binder::module_from_child_node(db, file_id, name_ref.syntax())
@@ -117,6 +132,8 @@ fn name_definition(
 
 #[cfg(test)]
 mod tests {
+    use test_utils::covers;
+
     use crate::mock_analysis::analysis_and_position;
 
     fn check_goto(fixuture: &str, expected: &str) {
@@ -183,6 +200,7 @@ mod tests {
 
     #[test]
     fn goto_definition_works_for_methods() {
+        covers!(goto_definition_works_for_methods);
         check_goto(
             "
             //- /lib.rs
@@ -197,15 +215,23 @@ mod tests {
             ",
             "frobnicate FN_DEF FileId(1) [27; 52) [30; 40)",
         );
+    }
 
+    #[test]
+    fn goto_definition_works_for_fields() {
+        covers!(goto_definition_works_for_fields);
         check_goto(
             "
             //- /lib.rs
-            mod <|>foo;
-            //- /foo/mod.rs
-            // empty
+            struct Foo {
+                spam: u32,
+            }
+
+            fn bar(foo: &Foo) {
+                foo.spam<|>;
+            }
             ",
-            "foo SOURCE_FILE FileId(2) [0; 10)",
+            "spam NAMED_FIELD_DEF FileId(1) [17; 26) [17; 21)",
         );
     }
 }

crates/ra_ide_api/src/marks.rs

@@ -1 +1,5 @@
-test_utils::marks!(inserts_parens_for_function_calls);
+test_utils::marks!(
+    inserts_parens_for_function_calls
+    goto_definition_works_for_methods
+    goto_definition_works_for_fields
+);

crates/ra_ide_api/src/navigation_target.rs

@@ -3,7 +3,7 @@ use ra_syntax::{
     SyntaxNode, AstNode, SmolStr, TextRange, ast,
     SyntaxKind::{self, NAME},
 };
-use hir::{ModuleSource};
+use hir::{ModuleSource, FieldSource};
 
 use crate::{FileSymbol, db::RootDatabase};
 
@@ -101,6 +101,17 @@ impl NavigationTarget {
         NavigationTarget::from_named(file_id.original_file(db), &*fn_def)
     }
 
+    pub(crate) fn from_field(db: &RootDatabase, field: hir::StructField) -> NavigationTarget {
+        let (file_id, field) = field.source(db);
+        let file_id = file_id.original_file(db);
+        match field {
+            FieldSource::Named(it) => NavigationTarget::from_named(file_id, &*it),
+            FieldSource::Pos(it) => {
+                NavigationTarget::from_syntax(file_id, "".into(), None, it.syntax())
+            }
+        }
+    }
+
     // TODO once Def::Item is gone, this should be able to always return a NavigationTarget
     pub(crate) fn from_def(
         db: &RootDatabase,