fix: support comments on extracted literals

.vscode/settings.json

@@ -11,7 +11,7 @@
   "editor.tabSize": 4,
   "editor.formatOnSave": true,
   "editor.codeActionsOnSave": {
-    "source.fixAll.eslint": true
+    "source.fixAll.eslint": "explicit"
   },
   "jest.autoRun": "off"
 }

src/Utils/extractLiterals.ts

@@ -6,31 +6,35 @@ import { DefinitionType } from "../Type/DefinitionType";
 import { EnumType } from "../Type/EnumType";
 import { LiteralType } from "../Type/LiteralType";
 import { UnionType } from "../Type/UnionType";
+import { derefAnnotatedType } from "./derefType";
 
 function* _extractLiterals(type: BaseType): Iterable<string> {
     if (!type) {
         return;
     }
-    if (type instanceof LiteralType) {
-        yield type.getValue().toString();
+
+    const dereffedType = derefAnnotatedType(type);
+
+    if (dereffedType instanceof LiteralType) {
+        yield dereffedType.getValue().toString();
         return;
     }
-    if (type instanceof UnionType || type instanceof EnumType) {
-        for (const t of type.getTypes()) {
+    if (dereffedType instanceof UnionType || dereffedType instanceof EnumType) {
+        for (const t of dereffedType.getTypes()) {
             yield* _extractLiterals(t);
         }
         return;
     }
-    if (type instanceof AliasType || type instanceof DefinitionType) {
-        yield* _extractLiterals(type.getType());
+    if (dereffedType instanceof AliasType || dereffedType instanceof DefinitionType) {
+        yield* _extractLiterals(dereffedType.getType());
         return;
     }
-    if (type instanceof BooleanType) {
+    if (dereffedType instanceof BooleanType) {
         yield* _extractLiterals(new UnionType([new LiteralType("true"), new LiteralType("false")]));
         return;
     }
 
-    throw new UnknownTypeError(type);
+    throw new UnknownTypeError(dereffedType);
 }
 
 export function extractLiterals(type: BaseType): string[] {

test/valid-data-type.test.ts

@@ -148,4 +148,6 @@ describe("valid-data-type", () => {
     it("type-satisfies", assertValidSchema("type-satisfies", "MyType"));
 
     it("ignore-export", assertValidSchema("ignore-export", "*"));
+
+    it("lowercase", assertValidSchema("lowercase", "MyType"));
 });

test/valid-data/lowercase/main.ts

@@ -0,0 +1,4 @@
+/** The built-in color schemes, cased. */
+type Foo = "Accent";
+
+export type MyType = Lowercase<Foo>;

test/valid-data/lowercase/schema.json

@@ -0,0 +1,10 @@
+{
+    "$ref": "#/definitions/MyType",
+    "$schema": "http://json-schema.org/draft-07/schema#",
+    "definitions": {
+      "MyType": {
+        "const": "accent",
+        "type": "string"
+      }
+    }
+  }