paths-plugin.js

"use strict";
/**
 * @license
 * Copyright Google LLC All Rights Reserved.
 *
 * Use of this source code is governed by an MIT-style license that can be
 * found in the LICENSE file at https://angular.dev/license
 */
var __createBinding = (this && this.__createBinding) || (Object.create ? (function(o, m, k, k2) {
    if (k2 === undefined) k2 = k;
    var desc = Object.getOwnPropertyDescriptor(m, k);
    if (!desc || ("get" in desc ? !m.__esModule : desc.writable || desc.configurable)) {
      desc = { enumerable: true, get: function() { return m[k]; } };
    }
    Object.defineProperty(o, k2, desc);
}) : (function(o, m, k, k2) {
    if (k2 === undefined) k2 = k;
    o[k2] = m[k];
}));
var __setModuleDefault = (this && this.__setModuleDefault) || (Object.create ? (function(o, v) {
    Object.defineProperty(o, "default", { enumerable: true, value: v });
}) : function(o, v) {
    o["default"] = v;
});
var __importStar = (this && this.__importStar) || (function () {
    var ownKeys = function(o) {
        ownKeys = Object.getOwnPropertyNames || function (o) {
            var ar = [];
            for (var k in o) if (Object.prototype.hasOwnProperty.call(o, k)) ar[ar.length] = k;
            return ar;
        };
        return ownKeys(o);
    };
    return function (mod) {
        if (mod && mod.__esModule) return mod;
        var result = {};
        if (mod != null) for (var k = ownKeys(mod), i = 0; i < k.length; i++) if (k[i] !== "default") __createBinding(result, mod, k[i]);
        __setModuleDefault(result, mod);
        return result;
    };
})();
Object.defineProperty(exports, "__esModule", { value: true });
exports.TypeScriptPathsPlugin = void 0;
const path = __importStar(require("node:path"));
class TypeScriptPathsPlugin {
    baseUrl;
    patterns;
    constructor(options) {
        if (options) {
            this.update(options);
        }
    }
    /**
     * Update the plugin with new path mapping option values.
     * The options will also be preprocessed to reduce the overhead of individual resolve actions
     * during a build.
     *
     * @param options The `paths` and `baseUrl` options from TypeScript's `CompilerOptions`.
     */
    update(options) {
        this.baseUrl = options.baseUrl;
        this.patterns = undefined;
        if (options.paths) {
            for (const [pattern, potentials] of Object.entries(options.paths)) {
                // Ignore any entries that would not result in a new mapping
                if (potentials.length === 0 || potentials.every((potential) => potential === '*')) {
                    continue;
                }
                const starIndex = pattern.indexOf('*');
                let prefix = pattern;
                let suffix;
                if (starIndex > -1) {
                    prefix = pattern.slice(0, starIndex);
                    if (starIndex < pattern.length - 1) {
                        suffix = pattern.slice(starIndex + 1);
                    }
                }
                this.patterns ??= [];
                this.patterns.push({
                    starIndex,
                    prefix,
                    suffix,
                    potentials: potentials.map((potential) => {
                        const potentialStarIndex = potential.indexOf('*');
                        if (potentialStarIndex === -1) {
                            return { hasStar: false, prefix: potential };
                        }
                        return {
                            hasStar: true,
                            prefix: potential.slice(0, potentialStarIndex),
                            suffix: potentialStarIndex < potential.length - 1
                                ? potential.slice(potentialStarIndex + 1)
                                : undefined,
                        };
                    }),
                });
            }
            // Sort patterns so that exact matches take priority then largest prefix match
            this.patterns?.sort((a, b) => {
                if (a.starIndex === -1) {
                    return -1;
                }
                else if (b.starIndex === -1) {
                    return 1;
                }
                else {
                    return b.starIndex - a.starIndex;
                }
            });
        }
    }
    apply(resolver) {
        const target = resolver.ensureHook('resolve');
        // To support synchronous resolvers this hook cannot be promise based.
        // Webpack supports synchronous resolution with `tap` and `tapAsync` hooks.
        resolver
            .getHook('described-resolve')
            .tapAsync('TypeScriptPathsPlugin', (request, resolveContext, callback) => {
            // Preprocessing of the options will ensure that `patterns` is either undefined or has elements to check
            if (!this.patterns) {
                callback();
                return;
            }
            if (!request || request.typescriptPathMapped) {
                callback();
                return;
            }
            const originalRequest = request.request || request.path;
            if (!originalRequest) {
                callback();
                return;
            }
            // Only work on Javascript/TypeScript issuers.
            if (!request?.context?.issuer?.match(/\.[cm]?[jt]sx?$/)) {
                callback();
                return;
            }
            // Absolute requests are not mapped
            if (path.isAbsolute(originalRequest)) {
                callback();
                return;
            }
            switch (originalRequest[0]) {
                case '.':
                    // Relative requests are not mapped
                    callback();
                    return;
                case '!':
                    // Ignore all webpack special requests
                    if (originalRequest.length > 1 && originalRequest[1] === '!') {
                        callback();
                        return;
                    }
                    break;
            }
            // A generator is used to limit the amount of replacements requests that need to be created.
            // For example, if the first one resolves, any others are not needed and do not need
            // to be created.
            const requests = this.createReplacementRequests(request, originalRequest);
            const tryResolve = () => {
                const next = requests.next();
                if (next.done) {
                    callback();
                    return;
                }
                resolver.doResolve(target, next.value, '', resolveContext, (error, result) => {
                    if (error) {
                        callback(error);
                    }
                    else if (result) {
                        callback(undefined, result);
                    }
                    else {
                        tryResolve();
                    }
                });
            };
            tryResolve();
        });
    }
    *findReplacements(originalRequest) {
        if (!this.patterns) {
            return;
        }
        // check if any path mapping rules are relevant
        for (const { starIndex, prefix, suffix, potentials } of this.patterns) {
            let partial;
            if (starIndex === -1) {
                // No star means an exact match is required
                if (prefix === originalRequest) {
                    partial = '';
                }
            }
            else if (starIndex === 0 && !suffix) {
                // Everything matches a single wildcard pattern ("*")
                partial = originalRequest;
            }
            else if (!suffix) {
                // No suffix means the star is at the end of the pattern
                if (originalRequest.startsWith(prefix)) {
                    partial = originalRequest.slice(prefix.length);
                }
            }
            else {
                // Star was in the middle of the pattern
                if (originalRequest.startsWith(prefix) && originalRequest.endsWith(suffix)) {
                    partial = originalRequest.substring(prefix.length, originalRequest.length - suffix.length);
                }
            }
            // If request was not matched, move on to the next pattern
            if (partial === undefined) {
                continue;
            }
            // Create the full replacement values based on the original request and the potentials
            // for the successfully matched pattern.
            for (const { hasStar, prefix, suffix } of potentials) {
                let replacement = prefix;
                if (hasStar) {
                    replacement += partial;
                    if (suffix) {
                        replacement += suffix;
                    }
                }
                yield replacement;
            }
        }
    }
    *createReplacementRequests(request, originalRequest) {
        for (const replacement of this.findReplacements(originalRequest)) {
            const targetPath = path.resolve(this.baseUrl ?? '', replacement);
            // Resolution in the original callee location, but with the updated request
            // to point to the mapped target location.
            yield {
                ...request,
                request: targetPath,
                typescriptPathMapped: true,
            };
            // If there is no extension. i.e. the target does not refer to an explicit
            // file, then this is a candidate for module/package resolution.
            const canBeModule = path.extname(targetPath) === '';
            if (canBeModule) {
                // Resolution in the target location, preserving the original request.
                // This will work with the `resolve-in-package` resolution hook, supporting
                // package exports for e.g. locally-built APF libraries.
                yield {
                    ...request,
                    path: targetPath,
                    typescriptPathMapped: true,
                };
            }
        }
    }
}
exports.TypeScriptPathsPlugin = TypeScriptPathsPlugin;