Remove Option<...> from result of Crate::root_module

There doesn't seem to be any need for it, and removing it simplies
several paths of code that depend on it.

crates/ra_assists/src/utils.rs

@@ -257,7 +257,7 @@ pub use prelude::*;
             .find(|dep| &dep.name.to_string() == std_crate)?
             .krate;
 
-        let mut module = std_crate.root_module(db)?;
+        let mut module = std_crate.root_module(db);
         for segment in path {
             module = module.children(db).find_map(|child| {
                 let name = child.name(db)?;

crates/ra_hir/src/code_model.rs

@@ -83,9 +83,9 @@ impl Crate {
             .collect()
     }
 
-    pub fn root_module(self, db: &dyn HirDatabase) -> Option<Module> {
+    pub fn root_module(self, db: &dyn HirDatabase) -> Module {
         let module_id = db.crate_def_map(self.id).root;
-        Some(Module::new(self, module_id))
+        Module::new(self, module_id)
     }
 
     pub fn root_file(self, db: &dyn HirDatabase) -> FileId {

crates/ra_ide/src/goto_definition.rs

@@ -40,7 +40,7 @@ pub(crate) fn goto_definition(
                 reference_definition(&sema, &name_ref).to_vec()
             },
             ast::Name(name) => {
-                let def = classify_name(&sema, &name)?.definition(sema.db)?;
+                let def = classify_name(&sema, &name)?.definition(sema.db);
                 let nav = def.try_to_nav(sema.db)?;
                 vec![nav]
             },
@@ -82,7 +82,8 @@ pub(crate) fn reference_definition(
     name_ref: &ast::NameRef,
 ) -> ReferenceResult {
     let name_kind = classify_name_ref(sema, name_ref);
-    if let Some(def) = name_kind.and_then(|def| def.definition(sema.db)) {
+    if let Some(def) = name_kind {
+        let def = def.definition(sema.db);
         return match def.try_to_nav(sema.db) {
             Some(nav) => ReferenceResult::Exact(nav),
             None => ReferenceResult::Approximate(Vec::new()),

crates/ra_ide/src/hover.rs

@@ -85,8 +85,8 @@ pub(crate) fn hover(db: &RootDatabase, position: FilePosition) -> Option<RangeIn
     let node = token.parent();
     let definition = match_ast! {
         match node {
-            ast::NameRef(name_ref) => classify_name_ref(&sema, &name_ref).and_then(|d| d.definition(sema.db)),
+            ast::NameRef(name_ref) => classify_name_ref(&sema, &name_ref).map(|d| d.definition(sema.db)),
-            ast::Name(name) => classify_name(&sema, &name).and_then(|d| d.definition(sema.db)),
+            ast::Name(name) => classify_name(&sema, &name).map(|d| d.definition(sema.db)),
             _ => None,
         }
     };

crates/ra_ide/src/references.rs

@@ -130,13 +130,13 @@ fn find_name(
     opt_name: Option<ast::Name>,
 ) -> Option<RangeInfo<Definition>> {
     if let Some(name) = opt_name {
-        let def = classify_name(sema, &name)?.definition(sema.db)?;
+        let def = classify_name(sema, &name)?.definition(sema.db);
         let range = name.syntax().text_range();
         return Some(RangeInfo::new(range, def));
     }
     let name_ref =
         sema.find_node_at_offset_with_descend::<ast::NameRef>(&syntax, position.offset)?;
-    let def = classify_name_ref(sema, &name_ref)?.definition(sema.db)?;
+    let def = classify_name_ref(sema, &name_ref)?.definition(sema.db);
     let range = name_ref.syntax().text_range();
     Some(RangeInfo::new(range, def))
 }

crates/ra_ide_db/src/defs.rs

@@ -93,19 +93,19 @@ pub enum NameClass {
 impl NameClass {
     pub fn into_definition(self, db: &dyn HirDatabase) -> Option<Definition> {
         Some(match self {
-            NameClass::ExternCrate(krate) => Definition::ModuleDef(krate.root_module(db)?.into()),
+            NameClass::ExternCrate(krate) => Definition::ModuleDef(krate.root_module(db).into()),
             NameClass::Definition(it) => it,
             NameClass::ConstReference(_) => return None,
             NameClass::FieldShorthand { local, field: _ } => Definition::Local(local),
         })
     }
 
-    pub fn definition(self, db: &dyn HirDatabase) -> Option<Definition> {
+    pub fn definition(self, db: &dyn HirDatabase) -> Definition {
-        Some(match self {
+        match self {
-            NameClass::ExternCrate(krate) => Definition::ModuleDef(krate.root_module(db)?.into()),
+            NameClass::ExternCrate(krate) => Definition::ModuleDef(krate.root_module(db).into()),
             NameClass::Definition(it) | NameClass::ConstReference(it) => it,
             NameClass::FieldShorthand { local: _, field } => field,
-        })
+        }
     }
 }
 
@@ -148,7 +148,7 @@ pub fn classify_name(sema: &Semantics<RootDatabase>, name: &ast::Name) -> Option
                         })
                         .and_then(|name_ref| classify_name_ref(sema, &name_ref))?;
 
-                    Some(NameClass::Definition(name_ref_class.definition(sema.db)?))
+                    Some(NameClass::Definition(name_ref_class.definition(sema.db)))
                 } else {
                     let extern_crate = it.syntax().parent().and_then(ast::ExternCrate::cast)?;
                     let resolved = sema.resolve_extern_crate(&extern_crate)?;
@@ -234,14 +234,12 @@ pub enum NameRefClass {
 }
 
 impl NameRefClass {
-    pub fn definition(self, db: &dyn HirDatabase) -> Option<Definition> {
+    pub fn definition(self, db: &dyn HirDatabase) -> Definition {
-        Some(match self {
+        match self {
-            NameRefClass::ExternCrate(krate) => {
+            NameRefClass::ExternCrate(krate) => Definition::ModuleDef(krate.root_module(db).into()),
-                Definition::ModuleDef(krate.root_module(db)?.into())
-            }
             NameRefClass::Definition(def) => def,
             NameRefClass::FieldShorthand { local, field: _ } => Definition::Local(local),
-        })
+        }
     }
 }
 

crates/rust-analyzer/src/cli/analysis_stats.rs

@@ -72,7 +72,7 @@ impl AnalysisStatsCmd {
             shuffle(&mut rng, &mut krates);
         }
         for krate in krates {
-            let module = krate.root_module(db).expect("crate without root module");
+            let module = krate.root_module(db);
             let file_id = module.definition_source(db).file_id;
             let file_id = file_id.original_file(db);
             let source_root = db.file_source_root(file_id);

crates/rust-analyzer/src/cli/diagnostics.rs

@@ -28,7 +28,7 @@ pub fn diagnostics(
     let mut work = Vec::new();
     let krates = Crate::all(db);
     for krate in krates {
-        let module = krate.root_module(db).expect("crate without root module");
+        let module = krate.root_module(db);
         let file_id = module.definition_source(db).file_id;
         let file_id = file_id.original_file(db);
         let source_root = db.file_source_root(file_id);