add support for multiple tsconfigs

Author: teoxoy

Diff for: index.js

@@ -7,11 +7,17 @@ const debug = require('debug');
 
 const log = debug('eslint-import-resolver-typescript');
 
+const extensions = Object.keys(require.extensions).concat(
+  '.ts',
+  '.tsx',
+  '.d.ts',
+);
+
 /**
  * @param {string} source the module to resolve; i.e './some-module'
  * @param {string} file the importing file's full path; i.e. '/usr/local/bin/file.js'
  */
-function resolveFile(source, file, config) {
+function resolveFile(source, file, options = {}) {
   log('looking for:', source);
 
   // don't worry about core node modules
@@ -24,38 +30,16 @@ function resolveFile(source, file, config) {
     };
   }
 
-  let foundTsPath = null;
-  const extensions = Object.keys(require.extensions).concat(
-    '.ts',
-    '.tsx',
-    '.d.ts',
-  );
-
-  // setup tsconfig-paths
-  const searchStart = config.directory || process.cwd();
-  const configLoaderResult = tsconfigPaths.loadConfig(searchStart);
-  if (configLoaderResult.resultType === 'success') {
-    const matchPath = tsconfigPaths.createMatchPath(
-      configLoaderResult.absoluteBaseUrl,
-      configLoaderResult.paths,
-    );
-
-    // look for files based on setup tsconfig "paths"
-    foundTsPath = matchPath(source, undefined, undefined, extensions);
-
-    if (foundTsPath) {
-      log('matched ts path:', foundTsPath);
-    }
-  } else {
-    log('failed to init tsconfig-paths:', configLoaderResult.message);
-    // this can happen if the user has problems with their tsconfig
-    // or if it's valid, but they don't have baseUrl set
+  initMappers(options);
+  const mappedPath = getMappedPath(source, file);
+  if (mappedPath) {
+    log('matched ts path:', mappedPath);
   }
 
-  // note that even if we match via tsconfig-paths, we still need to do a final resolve
+  // note that even if we map the path, we still need to do a final resolve
   let foundNodePath;
   try {
-    foundNodePath = resolve.sync(foundTsPath || source, {
+    foundNodePath = resolve.sync(mappedPath || source, {
       extensions,
       basedir: path.dirname(path.resolve(file)),
       packageFilter,
@@ -79,13 +63,76 @@ function resolveFile(source, file, config) {
     found: false,
   };
 }
+
 function packageFilter(pkg) {
   if (pkg['jsnext:main']) {
     pkg['main'] = pkg['jsnext:main'];
   }
   return pkg;
 }
 
+/**
+ * @param {string} source the module to resolve; i.e './some-module'
+ * @param {string} file the importing file's full path; i.e. '/usr/local/bin/file.js'
+ * @returns The mapped path of the module or undefined
+ */
+function getMappedPath(source, file) {
+  const paths = mappers
+    .map(mapper => mapper(source, file))
+    .filter(path => !!path);
+
+  if (paths.length > 1) {
+    log('found multiple matching ts paths:', paths);
+  }
+
+  return paths[0];
+}
+
+let mappers;
+function initMappers(options) {
+  if (mappers) {
+    return;
+  }
+
+  const isArrayOfStrings = array =>
+    Array.isArray(array) && array.every(o => typeof o === 'string');
+
+  const configPaths =
+    typeof options.directory === 'string'
+      ? [options.directory]
+      : isArrayOfStrings(options.directory)
+      ? options.directory
+      : [process.cwd()];
+
+  mappers = configPaths
+    .map(path => tsconfigPaths.loadConfig(path))
+    .filter(configLoaderResult => {
+      const success = configLoaderResult.resultType === 'success';
+      if (!success) {
+        // this can happen if the user has problems with their tsconfig
+        // or if it's valid, but they don't have baseUrl set
+        log('failed to init tsconfig-paths:', configLoaderResult.message);
+      }
+      return success;
+    })
+    .map(configLoaderResult => {
+      const matchPath = tsconfigPaths.createMatchPath(
+        configLoaderResult.absoluteBaseUrl,
+        configLoaderResult.paths,
+      );
+
+      return (source, file) => {
+        // exclude files that are not part of the config base url
+        if (!file.includes(configLoaderResult.absoluteBaseUrl)) {
+          return undefined;
+        }
+
+        // look for files based on setup tsconfig "paths"
+        return matchPath(source, undefined, undefined, extensions);
+      };
+    });
+}
+
 module.exports = {
   interfaceVersion: 2,
   resolve: resolveFile,