Add support for external resolution on @link tags

Half of #2030 complete! externalSymbolLinkMappings tomorrow.

.config/typedoc.json

@@ -8,7 +8,8 @@
         "SORT_STRATEGIES",
         "_ModelToObject",
         "EventHooksMomento",
-        "MarkedPlugin"
+        "MarkedPlugin",
+        "MeaningKeywords"
     ],
     "sort": ["kind", "instance-first", "required-first", "alphabetical"],
     "entryPoints": ["../src"],

CHANGELOG.md

@@ -1,5 +1,14 @@
 # Unreleased
 
+### Features
+
+-   External link resolvers defined with `addUnknownSymbolResolver` will now be checked when resolving `@link` tags, #2030.
+    Note: To support this, resolution will now happen during conversion, and as such, `Renderer.addUnknownSymbolResolver` has been
+    soft deprecated in favor of `Converter.addUnknownSymbolResolver`. Plugins should update to use the method on `Converter`.
+    `DefaultThemeRenderContext.attemptExternalResolution` has also been deprecated since it will repeat work done during conversion,
+    use `ReferenceType.externalUrl` instead.
+-   Added `Converter.addUnknownSymbolResolver` for use by plugins supporting external links.
+
 ### Bug Fixes
 
 -   Fixed conversion of object literal types containing construct signatures, #2036.

internal-docs/third-party-symbols.md

@@ -9,17 +9,42 @@ and no link will be rendered unless provided by another resolver.
 The following plugin will resolve a few types from React to links on the official React documentation site.
 
 ```ts
-import { Application } from "typedoc";
+import { Application, type DeclarationReference } from "typedoc";
 
 const knownSymbols = {
     Component: "https://reactjs.org/docs/react-component.html",
     PureComponent: "https://reactjs.org/docs/react-api.html#reactpurecomponent",
 };
 
 export function load(app: Application) {
-    app.renderer.addUnknownSymbolResolver("@types/react", (name: string) => {
-        if (knownSymbols.hasOwnProperty(name)) {
-            return knownSymbols[name as never];
+    app.converter.addUnknownSymbolResolver((ref: DeclarationReference) => {
+        if (
+            ref.moduleSource !== "@types/react" &&
+            ref.moduleSource !== "react"
+        ) {
+            return;
+        }
+
+        // If someone did {@link react!}, link them directly to the home page.
+        if (!ref.symbolReference) {
+            return "https://reactjs.org/";
+        }
+
+        // Otherwise, we need to navigate through the symbol reference to
+        // determine where they meant to link to. Since the symbols we know
+        // about are all a single "level" deep, this is pretty simple.
+
+        if (!ref.symbolReference.path) {
+            // Someone included a meaning, but not a path.
+            // https://typedoc.org/guides/declaration-references/#meaning
+            return;
+        }
+
+        if (ref.symbolReference.path.length === 1) {
+            const name = ref.symbolReference.path[0].path;
+            if (knownSymbols.hasOwnProperty(name)) {
+                return knownSymbols[name as never];
+            }
         }
     });
 }

src/index.ts

@@ -4,7 +4,16 @@ export { EventDispatcher, Event } from "./lib/utils/events";
 export { resetReflectionID } from "./lib/models/reflections/abstract";
 export { normalizePath } from "./lib/utils/fs";
 export * from "./lib/models";
-export { Converter, Context, type CommentParserConfig } from "./lib/converter";
+export {
+    Converter,
+    Context,
+    type CommentParserConfig,
+    type DeclarationReference,
+    type SymbolReference,
+    type ComponentPath,
+    type Meaning,
+    type MeaningKeyword,
+} from "./lib/converter";
 
 export {
     Renderer,

src/lib/converter/comments/linkResolver.ts

@@ -7,7 +7,10 @@ import {
     Reflection,
 } from "../../models";
 import type { Logger, ValidationOptions } from "../../utils";
-import { parseDeclarationReference } from "./declarationReference";
+import {
+    DeclarationReference,
+    parseDeclarationReference,
+} from "./declarationReference";
 import { resolveDeclarationReference } from "./declarationReferenceResolver";
 
 const urlPrefix = /^(http|ftp)s?:\/\//;
@@ -17,7 +20,8 @@ export function resolveLinks(
     comment: Comment,
     reflection: Reflection,
     validation: ValidationOptions,
-    logger: Logger
+    logger: Logger,
+    attemptExternalResolve: (ref: DeclarationReference) => string | undefined
 ) {
     let warned = false;
     const warn = () => {
@@ -34,15 +38,17 @@ export function resolveLinks(
         comment.summary,
         warn,
         validation,
-        logger
+        logger,
+        attemptExternalResolve
     );
     for (const tag of comment.blockTags) {
         tag.content = resolvePartLinks(
             reflection,
             tag.content,
             warn,
             validation,
-            logger
+            logger,
+            attemptExternalResolve
         );
     }
 
@@ -52,7 +58,8 @@ export function resolveLinks(
             reflection.readme,
             warn,
             validation,
-            logger
+            logger,
+            attemptExternalResolve
         );
     }
 }
@@ -62,10 +69,18 @@ export function resolvePartLinks(
     parts: readonly CommentDisplayPart[],
     warn: () => void,
     validation: ValidationOptions,
-    logger: Logger
+    logger: Logger,
+    attemptExternalResolve: (ref: DeclarationReference) => string | undefined
 ): CommentDisplayPart[] {
     return parts.flatMap((part) =>
-        processPart(reflection, part, warn, validation, logger)
+        processPart(
+            reflection,
+            part,
+            warn,
+            validation,
+            logger,
+            attemptExternalResolve
+        )
     );
 }
 
@@ -74,7 +89,8 @@ function processPart(
     part: CommentDisplayPart,
     warn: () => void,
     validation: ValidationOptions,
-    logger: Logger
+    logger: Logger,
+    attemptExternalResolve: (ref: DeclarationReference) => string | undefined
 ): CommentDisplayPart | CommentDisplayPart[] {
     if (part.kind === "text" && brackets.test(part.text)) {
         warn();
@@ -87,11 +103,16 @@ function processPart(
             part.tag === "@linkcode" ||
             part.tag === "@linkplain"
         ) {
-            return resolveLinkTag(reflection, part, (msg: string) => {
-                if (validation.invalidLink) {
-                    logger.warn(msg);
+            return resolveLinkTag(
+                reflection,
+                part,
+                attemptExternalResolve,
+                (msg: string) => {
+                    if (validation.invalidLink) {
+                        logger.warn(msg);
+                    }
                 }
-            });
+            );
         }
     }
 
@@ -101,6 +122,7 @@ function processPart(
 function resolveLinkTag(
     reflection: Reflection,
     part: InlineTagDisplayPart,
+    attemptExternalResolve: (ref: DeclarationReference) => string | undefined,
     warn: (message: string) => void
 ) {
     let pos = 0;
@@ -118,6 +140,11 @@ function resolveLinkTag(
         // Got one, great! Try to resolve the link
         target = resolveDeclarationReference(reflection, declRef[0]);
         pos = declRef[1];
+
+        // If we didn't find a link, it might be a @link tag to an external symbol, check that next.
+        if (!target) {
+            target = attemptExternalResolve(declRef[0]);
+        }
     }
 
     if (!target) {
@@ -133,7 +160,7 @@ function resolveLinkTag(
     // method... this should go away in 0.24, once people have had a chance to migrate any failing links.
     if (!target) {
         const resolved = legacyResolveLinkTag(reflection, part);
-        if (resolved) {
+        if (resolved.target) {
             warn(
                 `Failed to resolve {@link ${origText}} in ${reflection.getFriendlyFullName()} with declaration references. This link will break in v0.24.`
             );

src/lib/converter/converter.ts

@@ -28,6 +28,7 @@ import type {
 import { parseComment } from "./comments/parser";
 import { lexCommentString } from "./comments/rawLexer";
 import { resolvePartLinks, resolveLinks } from "./comments/linkResolver";
+import type { DeclarationReference } from "./comments/declarationReference";
 
 /**
  * Compiles source files using TypeScript and converts compiler symbols to reflections.
@@ -41,29 +42,29 @@ export class Converter extends ChildableComponent<
     Application,
     ConverterComponent
 > {
-    /**
-     * The human readable name of the project. Used within the templates to set the title of the document.
-     */
-    @BindOption("name")
-    name!: string;
-
+    /** @internal */
     @BindOption("externalPattern")
     externalPattern!: string[];
     private externalPatternCache?: Minimatch[];
     private excludeCache?: Minimatch[];
 
+    /** @internal */
     @BindOption("excludeExternals")
     excludeExternals!: boolean;
 
+    /** @internal */
     @BindOption("excludeNotDocumented")
     excludeNotDocumented!: boolean;
 
+    /** @internal */
     @BindOption("excludePrivate")
     excludePrivate!: boolean;
 
+    /** @internal */
     @BindOption("excludeProtected")
     excludeProtected!: boolean;
 
+    /** @internal */
     @BindOption("commentStyle")
     commentStyle!: CommentStyle;
 
@@ -72,6 +73,9 @@ export class Converter extends ChildableComponent<
     validation!: ValidationOptions;
 
     private _config?: CommentParserConfig;
+    private _externalSymbolResolvers: Array<
+        (ref: DeclarationReference) => string | undefined
+    > = [];
 
     get config(): CommentParserConfig {
         return this._config || this._buildCommentParserConfig();
@@ -164,7 +168,9 @@ export class Converter extends ChildableComponent<
         const programs = entryPoints.map((e) => e.program);
         this.externalPatternCache = void 0;
 
-        const project = new ProjectReflection(this.name);
+        const project = new ProjectReflection(
+            this.application.options.getValue("name")
+        );
         const context = new Context(this, programs, project);
 
         this.trigger(Converter.EVENT_BEGIN, context);
@@ -211,6 +217,32 @@ export class Converter extends ChildableComponent<
         );
     }
 
+    /**
+     * Adds a new resolver that the theme can use to try to figure out how to link to a symbol declared
+     * by a third-party library which is not included in the documentation.
+     *
+     * The resolver function will be passed a declaration reference which it can attempt to resolve. If
+     * resolution fails, the function should return undefined.
+     *
+     * Note: This will be used for both references to types declared in node_modules (in which case the
+     * reference passed will have the `moduleSource` set and the `symbolReference` will navigate via `.`)
+     * and user defined \{\@link\} tags which cannot be resolved.
+     * @since 0.22.14
+     */
+    addUnknownSymbolResolver(
+        resolver: (ref: DeclarationReference) => string | undefined
+    ): void {
+        this._externalSymbolResolvers.push(resolver);
+    }
+
+    /** @internal */
+    resolveExternalLink(ref: DeclarationReference): string | undefined {
+        for (const resolver of this._externalSymbolResolvers) {
+            const resolved = resolver(ref);
+            if (resolved) return resolved;
+        }
+    }
+
     resolveLinks(comment: Comment, owner: Reflection): void;
     resolveLinks(
         parts: readonly CommentDisplayPart[],
@@ -221,7 +253,13 @@ export class Converter extends ChildableComponent<
         owner: Reflection
     ): CommentDisplayPart[] | undefined {
         if (comment instanceof Comment) {
-            resolveLinks(comment, owner, this.validation, this.owner.logger);
+            resolveLinks(
+                comment,
+                owner,
+                this.validation,
+                this.owner.logger,
+                (ref) => this.resolveExternalLink(ref)
+            );
         } else {
             let warned = false;
             const warn = () => {
@@ -238,7 +276,8 @@ export class Converter extends ChildableComponent<
                 comment,
                 warn,
                 this.validation,
-                this.owner.logger
+                this.owner.logger,
+                (ref) => this.resolveExternalLink(ref)
             );
         }
     }

src/lib/converter/index.ts

@@ -2,5 +2,12 @@ export { Context } from "./context";
 export { Converter } from "./converter";
 export type { CommentParserConfig } from "./comments/index";
 export { convertDefaultValue, convertExpression } from "./convert-expression";
+export type {
+    DeclarationReference,
+    SymbolReference,
+    ComponentPath,
+    Meaning,
+    MeaningKeyword,
+} from "./comments/declarationReference";
 
 import "./plugins/index";

src/lib/converter/plugins/LinkResolverPlugin.ts

@@ -3,6 +3,7 @@ import type { Context } from "../../converter";
 import { ConverterEvents } from "../converter-events";
 import { BindOption, ValidationOptions } from "../../utils";
 import { DeclarationReflection } from "../../models";
+import { discoverAllReferenceTypes } from "../../utils/reflections";
 
 /**
  * A plugin that resolves `{@link Foo}` tags.
@@ -43,5 +44,16 @@ export class LinkResolverPlugin extends ConverterComponent {
                 context.project
             );
         }
+
+        for (const { type } of discoverAllReferenceTypes(
+            context.project,
+            false
+        )) {
+            if (!type.reflection) {
+                type.externalUrl = context.converter.resolveExternalLink(
+                    type.toDeclarationReference()
+                );
+            }
+        }
     }
 }