knip/dist/graph-explorer/walk-down.js

Find and fix unused dependencies, exports and files in your TypeScript and JavaScript projects

import { STOP } from "./constants.js";
import { getAliasReExportMap, getPassThroughReExportSources, getStarReExportSources } from "./visitors.js";
export const walkDown = (graph, filePath, identifier, visitor, entryPaths, visited = new Set()) => {
    const key = `${filePath}:${identifier}`;
    if (visited.has(key))
        return false;
    visited.add(key);
    const file = graph.get(filePath);
    if (!file?.importedBy)
        return false;
    const restIds = identifier.split('.');
    const id = restIds.shift();
    if (!id)
        return false;
    const imported = file.importedBy;
    const importedByFiles = imported.import.get(id);
    if (importedByFiles) {
        for (const importingFile of importedByFiles) {
            const isEntry = entryPaths.has(importingFile);
            if (visitor(filePath, id, importingFile, id, isEntry, 'import') === STOP)
                return true;
        }
    }
    const importAsAliases = imported.importAs.get(id);
    if (importAsAliases) {
        for (const [alias, byFilePaths] of importAsAliases) {
            for (const importingFile of byFilePaths) {
                const isEntry = entryPaths.has(importingFile);
                if (visitor(filePath, id, importingFile, alias, isEntry, 'importAs') === STOP)
                    return true;
            }
        }
    }
    for (const [namespace, byFilePaths] of imported.importNs) {
        for (const importingFile of byFilePaths) {
            const isEntry = entryPaths.has(importingFile);
            if (visitor(filePath, identifier, importingFile, `${namespace}.${identifier}`, isEntry, 'importNS') === STOP) {
                return true;
            }
        }
    }
    let done = false;
    if (!done) {
        const passThroughSources = getPassThroughReExportSources(imported, id);
        if (passThroughSources) {
            for (const reExportingFile of passThroughSources) {
                const isEntry = entryPaths.has(reExportingFile);
                if (visitor(filePath, id, reExportingFile, id, isEntry, 'reExport') === STOP) {
                    done = true;
                    break;
                }
                if (walkDown(graph, reExportingFile, identifier, visitor, entryPaths, visited)) {
                    done = true;
                    break;
                }
            }
        }
    }
    if (!done) {
        const aliasReExportMap = getAliasReExportMap(imported, id);
        if (aliasReExportMap) {
            for (const [alias, sources] of aliasReExportMap) {
                for (const reExportingFile of sources) {
                    const isEntry = entryPaths.has(reExportingFile);
                    if (visitor(filePath, id, reExportingFile, alias, isEntry, 'reExportAs') === STOP) {
                        done = true;
                        break;
                    }
                    if (walkDown(graph, reExportingFile, [alias, ...restIds].join('.'), visitor, entryPaths, visited)) {
                        done = true;
                        break;
                    }
                }
                if (done)
                    break;
            }
        }
    }
    if (!done) {
        for (const [namespace, sources] of imported.reExportNs) {
            for (const reExportingFile of sources) {
                const isEntry = entryPaths.has(reExportingFile);
                if (visitor(filePath, identifier, reExportingFile, `${namespace}.${identifier}`, isEntry, 'reExportNS') === STOP) {
                    done = true;
                    break;
                }
                if (walkDown(graph, reExportingFile, `${namespace}.${identifier}`, visitor, entryPaths, visited)) {
                    done = true;
                    break;
                }
            }
            if (done)
                break;
        }
    }
    if (!done) {
        const starSources = getStarReExportSources(imported);
        if (starSources) {
            for (const reExportingFile of starSources) {
                const isEntry = entryPaths.has(reExportingFile);
                if (visitor(filePath, id, reExportingFile, id, isEntry, 'reExportStar') === STOP) {
                    done = true;
                    break;
                }
                if (walkDown(graph, reExportingFile, identifier, visitor, entryPaths, visited)) {
                    done = true;
                    break;
                }
            }
        }
    }
    return done;
};