Prevent namespaces being used as variables

src/DiagnosticMessages.ts

@@ -696,7 +696,7 @@ export let DiagnosticMessages = {
         severity: DiagnosticSeverity.Error
     }),
     detectedTooDeepFileSource: (numberOfParentDirectories: number) => ({
-        message: `Expected directory depth no larger than 7, but found ${numberOfParentDirectories}.`,
+        message: `Expected directory depth no larger than 7, but found ${numberOfParentDirectories}`,
         code: 1134,
         severity: DiagnosticSeverity.Error
     }),
@@ -709,6 +709,11 @@ export let DiagnosticMessages = {
         message: `${keyword} must be declared at the root level or within a namespace`,
         code: 1136,
         severity: DiagnosticSeverity.Error
+    }),
+    namespaceCannotBeReferencedDirectly: () => ({
+        message: `Namespace cannot be referenced directly`,
+        code: 1137,
+        severity: DiagnosticSeverity.Error
     })
 };
 

src/Scope.spec.ts

@@ -119,7 +119,8 @@ describe('Scope', () => {
         program.validate();
         expectDiagnostics(program, [
             DiagnosticMessages.variableMayNotHaveSameNameAsNamespace('namea'),
-            DiagnosticMessages.variableMayNotHaveSameNameAsNamespace('NAMEA')
+            DiagnosticMessages.variableMayNotHaveSameNameAsNamespace('NAMEA'),
+            DiagnosticMessages.namespaceCannotBeReferencedDirectly()
         ]);
     });
 

src/bscPlugin/validation/ScopeValidator.ts

@@ -108,12 +108,12 @@ export class ScopeValidator {
                 continue;
             }
             //catch unknown namespace items
-            const processedNames: string[] = [firstNamespacePart];
+            let entityName = firstNamespacePart;
+            let entityNameLower = firstNamespacePart.toLowerCase();
             for (let i = 1; i < info.parts.length; i++) {
                 const part = info.parts[i];
-                processedNames.push(part.name.text);
-                const entityName = processedNames.join('.');
-                const entityNameLower = entityName.toLowerCase();
+                entityName += '.' + part.name.text;
+                entityNameLower += '.' + part.name.text.toLowerCase();
 
                 //if this is an enum member, stop validating here to prevent errors further down the chain
                 if (scope.getEnumMemberMap().has(entityNameLower)) {
@@ -153,6 +153,14 @@ export class ScopeValidator {
                     continue outer;
                 }
             }
+            //if the full expression is a namespace path, this is an illegal statement because namespaces don't exist at runtme
+            if (scope.namespaceLookup.has(entityNameLower)) {
+                this.addMultiScopeDiagnostic({
+                    ...DiagnosticMessages.namespaceCannotBeReferencedDirectly(),
+                    range: info.expression.range,
+                    file: file
+                }, 'When used in scope');
+            }
         }
     }
 

src/files/BrsFile.spec.ts

@@ -68,6 +68,37 @@ describe('BrsFile', () => {
         });
     });
 
+    it('flags namespaces used as variables', () => {
+        program.setFile('source/main.bs', `
+            sub main()
+                alpha.beta.charlie.test()
+                print alpha
+                print alpha.beta
+                print alpha.beta.charlie
+            end sub
+
+            namespace alpha
+                namespace beta
+                    namespace charlie
+                        sub test()
+                        end sub
+                    end namespace
+                end namespace
+            end namespace
+        `);
+        program.validate();
+        expectDiagnostics(program, [{
+            ...DiagnosticMessages.namespaceCannotBeReferencedDirectly(),
+            range: util.createRange(3, 22, 3, 27)
+        }, {
+            ...DiagnosticMessages.namespaceCannotBeReferencedDirectly(),
+            range: util.createRange(4, 22, 4, 32)
+        }, {
+            ...DiagnosticMessages.namespaceCannotBeReferencedDirectly(),
+            range: util.createRange(5, 22, 5, 40)
+        }]);
+    });
+
     it('supports the third parameter in CreateObject', () => {
         program.setFile('source/main.brs', `
             sub main()