feat: scoping for named types (#563)

Closes partially #540

### Summary of Changes

* Implement scoping for named types

---------

Co-authored-by: megalinter-bot <[email protected]>

Author: lars-reimann

src/language/scoping/safe-ds-scope-computation.ts

@@ -8,33 +8,82 @@ import {
 } from 'langium';
 import {
     isSdsClass,
+    isSdsDeclaration,
+    isSdsEnum,
     isSdsEnumVariant,
     isSdsFunction,
+    isSdsModule,
     isSdsTypeParameter,
     isSdsTypeParameterList,
+    SdsClass,
+    SdsEnum,
     SdsTypeParameter,
 } from '../generated/ast.js';
 
 export class SafeDsScopeComputation extends DefaultScopeComputation {
     override processNode(node: AstNode, document: LangiumDocument, scopes: PrecomputedScopes): void {
-        if (isSdsTypeParameter(node)) {
+        if (isSdsClass(node)) {
+            this.processSdsClass(node, document, scopes);
+        } else if (isSdsEnum(node)) {
+            this.processSdsEnum(node, document, scopes);
+        } else if (isSdsTypeParameter(node)) {
             this.processSdsTypeParameter(node, document, scopes);
         } else {
             super.processNode(node, document, scopes);
         }
     }
 
+    private processSdsClass(node: SdsClass, document: LangiumDocument, scopes: PrecomputedScopes): void {
+        const name = this.nameProvider.getName(node);
+        if (!name) {
+            return;
+        }
+
+        const description = this.descriptions.createDescription(node, name, document);
+
+        this.addToScopesIfKeyIsDefined(scopes, node.parameterList, description);
+        this.addToScopesIfKeyIsDefined(scopes, node.constraintList, description);
+        this.addToScopesIfKeyIsDefined(scopes, node.body, description);
+
+        const containingDeclaration = getContainerOfType(node.$container, isSdsDeclaration);
+        if (isSdsModule(containingDeclaration)) {
+            this.addToScopesIfKeyIsDefined(scopes, containingDeclaration, description);
+        }
+    }
+
+    private processSdsEnum(node: SdsEnum, document: LangiumDocument, scopes: PrecomputedScopes): void {
+        const name = this.nameProvider.getName(node);
+        if (!name) {
+            return;
+        }
+
+        const description = this.descriptions.createDescription(node, name, document);
+
+        this.addToScopesIfKeyIsDefined(scopes, node.body, description);
+
+        const containingDeclaration = getContainerOfType(node.$container, isSdsDeclaration);
+        if (isSdsModule(containingDeclaration)) {
+            this.addToScopesIfKeyIsDefined(scopes, containingDeclaration, description);
+        }
+    }
+
     private processSdsTypeParameter(
         node: SdsTypeParameter,
         document: LangiumDocument,
         scopes: PrecomputedScopes,
     ): void {
         const containingDeclaration = getContainerOfType(node, isSdsTypeParameterList)?.$container;
         if (!containingDeclaration) {
+            /* c8 ignore next 2 */
             return;
         }
 
         const name = this.nameProvider.getName(node);
+        if (!name) {
+            /* c8 ignore next 2 */
+            return;
+        }
+
         const description = this.descriptions.createDescription(node, name, document);
 
         if (isSdsClass(containingDeclaration)) {

src/language/scoping/safe-ds-scope-provider.ts

@@ -1,18 +1,72 @@
 import { DefaultScopeProvider, EMPTY_SCOPE, getContainerOfType, ReferenceInfo, Scope } from 'langium';
-import { isSdsSegment, isSdsYield } from '../generated/ast.js';
+import {
+    isSdsClass,
+    isSdsEnum,
+    isSdsMemberType,
+    isSdsNamedType,
+    isSdsNamedTypeDeclaration,
+    isSdsSegment,
+    isSdsYield,
+    SdsMemberType,
+    SdsNamedTypeDeclaration,
+    SdsType,
+    SdsYield,
+} from '../generated/ast.js';
 import { resultsOrEmpty } from '../helpers/astShortcuts.js';
 
 export class SafeDsScopeProvider extends DefaultScopeProvider {
     override getScope(context: ReferenceInfo): Scope {
-        if (isSdsYield(context.container) && context.property === 'result') {
-            return this.getScopeForYieldResult(context);
+        if (isSdsNamedType(context.container) && context.property === 'declaration') {
+            const node = context.container;
+
+            if (isSdsMemberType(node.$container) && node.$containerProperty === 'member') {
+                return this.getScopeForMemberTypeMember(node.$container);
+            } else {
+                return super.getScope(context);
+            }
+        } else if (isSdsYield(context.container) && context.property === 'result') {
+            return this.getScopeForYieldResult(context.container);
         } else {
             return super.getScope(context);
         }
     }
 
-    getScopeForYieldResult(context: ReferenceInfo): Scope {
-        const containingSegment = getContainerOfType(context.container, isSdsSegment);
+    private getScopeForMemberTypeMember(node: SdsMemberType): Scope {
+        const declaration = this.getUniqueReferencedDeclarationForType(node.receiver);
+        if (!declaration) {
+            return EMPTY_SCOPE;
+        }
+
+        if (isSdsClass(declaration)) {
+            const members = declaration.body?.members ?? [];
+            return this.createScopeForNodes(members.filter(isSdsNamedTypeDeclaration));
+        } else if (isSdsEnum(declaration)) {
+            const variants = declaration.body?.variants ?? [];
+            return this.createScopeForNodes(variants);
+        } else {
+            return EMPTY_SCOPE;
+        }
+    }
+
+    /**
+     * Returns the unique declaration that is referenced by this type. If the type references none or multiple
+     * declarations, undefined is returned.
+     *
+     * @param type The type to get the referenced declaration for.
+     * @returns The referenced declaration or undefined.
+     */
+    private getUniqueReferencedDeclarationForType(type: SdsType): SdsNamedTypeDeclaration | undefined {
+        if (isSdsNamedType(type)) {
+            return type.declaration.ref;
+        } else if (isSdsMemberType(type)) {
+            return type.member.declaration.ref;
+        } else {
+            return undefined;
+        }
+    }
+
+    private getScopeForYieldResult(node: SdsYield): Scope {
+        const containingSegment = getContainerOfType(node, isSdsSegment);
         if (!containingSegment) {
             return EMPTY_SCOPE;
         }

tests/resources/scoping/annotation calls/on annotation/main.sdstest

@@ -8,8 +8,12 @@ annotation »Before«
 // $TEST$ references after
 @»After«
 // $TEST$ unresolved
+@»NotAnAnnotation«
+// $TEST$ unresolved
 @»Unresolved«
 annotation MyAnnotation
 
 // $TEST$ target after
 annotation »After«
+
+class NotAnAnnotation

tests/resources/scoping/annotation calls/on attribute/main.sdstest

@@ -9,9 +9,13 @@ class MyClass {
     // $TEST$ references after
     @»After«
     // $TEST$ unresolved
+    @»NotAnAnnotation«
+    // $TEST$ unresolved
     @»Unresolved«
     attr myAttribute: Int
 }
 
 // $TEST$ target after
 annotation »After«
+
+class NotAnAnnotation

tests/resources/scoping/annotation calls/on class/main.sdstest

@@ -8,8 +8,12 @@ annotation »Before«
 // $TEST$ references after
 @»After«
 // $TEST$ unresolved
+@»NotAnAnnotation«
+// $TEST$ unresolved
 @»Unresolved«
 class MyClass
 
 // $TEST$ target after
 annotation »After«
+
+class NotAnAnnotation

tests/resources/scoping/annotation calls/on enum variant/main.sdstest

@@ -9,9 +9,13 @@ enum MyEnum {
     // $TEST$ references after
     @»After«
     // $TEST$ unresolved
+    @»NotAnAnnotation«
+    // $TEST$ unresolved
     @»Unresolved«
     MyEnumVariant
 }
 
 // $TEST$ target after
 annotation »After«
+
+class NotAnAnnotation

tests/resources/scoping/annotation calls/on enum/main.sdstest

@@ -8,8 +8,12 @@ annotation »Before«
 // $TEST$ references after
 @»After«
 // $TEST$ unresolved
+@»NotAnAnnotation«
+// $TEST$ unresolved
 @»Unresolved«
 enum MyEnum
 
 // $TEST$ target after
 annotation »After«
+
+class NotAnAnnotation

tests/resources/scoping/annotation calls/on function/main.sdstest

@@ -8,8 +8,12 @@ annotation »Before«
 // $TEST$ references after
 @»After«
 // $TEST$ unresolved
+@»NotAnAnnotation«
+// $TEST$ unresolved
 @»Unresolved«
 fun myFunction()
 
 // $TEST$ target after
 annotation »After«
+
+class NotAnAnnotation

tests/resources/scoping/annotation calls/on module/main.sdstest

@@ -1,9 +1,13 @@
 // $TEST$ references annotation
 @»MyAnnotation«
 // $TEST$ unresolved
+@»NotAnAnnotation«
+// $TEST$ unresolved
 @»Unresolved«
 
 package test.scoping.annotationCalls.onModule
 
 // $TEST$ target annotation 
 annotation »MyAnnotation«
+
+class NotAnAnnotation

tests/resources/scoping/annotation calls/on parameter/main.sdstest

@@ -9,9 +9,13 @@ fun myFunction(
     // $TEST$ references after
     @»After«
     // $TEST$ unresolved
+    @»NotAnAnnotation«
+    // $TEST$ unresolved
     @»Unresolved«
     myParameter: Int
 )
 
 // $TEST$ target after
 annotation »After«
+
+class NotAnAnnotation