Allow overriding tsconfig options from within tsconfig.json

src/lib/utils/options/declaration.ts

@@ -110,6 +110,7 @@ export interface TypeDocOptionMap {
     logger: unknown; // string | Function
     logLevel: typeof LogLevel;
     markedOptions: unknown;
+    compilerOptions: unknown;
 
     // Validation
     treatWarningsAsErrors: boolean;

src/lib/utils/options/options.ts

@@ -328,8 +328,13 @@ export class Options {
     fixCompilerOptions(
         options: Readonly<ts.CompilerOptions>
     ): ts.CompilerOptions {
+        const overrides = this.getValue("compilerOptions");
         const result = { ...options };
 
+        if (overrides) {
+            Object.assign(result, overrides);
+        }
+
         if (
             this.getValue("emit") !== "both" &&
             this.getValue("emit") !== true

src/lib/utils/options/sources/typedoc.ts

@@ -327,6 +327,22 @@ export function addTypeDocOptions(options: Pick<Options, "addDeclaration">) {
             }
         },
     });
+    options.addDeclaration({
+        name: "compilerOptions",
+        help: "Selectively override the TypeScript compiler options used by TypeDoc.",
+        type: ParameterType.Mixed,
+        validate(value) {
+            if (
+                typeof value !== "object" ||
+                Array.isArray(value) ||
+                value == null
+            ) {
+                throw new Error(
+                    "The 'compilerOptions' option must be a non-array object."
+                );
+            }
+        },
+    });
 
     options.addDeclaration({
         name: "treatWarningsAsErrors",

src/test/utils/options/default-options.test.ts

@@ -55,6 +55,14 @@ describe("Default Options", () => {
         });
     });
 
+    describe("compilerOptions", () => {
+        it("Errors if given a non-object", () => {
+            throws(() => opts.setValue("markedOptions", null));
+            throws(() => opts.setValue("markedOptions", "bad"));
+            throws(() => opts.setValue("markedOptions", []));
+        });
+    });
+
     describe("requiredToBeDocumented", () => {
         it("Works with valid values", () => {
             doesNotThrow(() =>