fix: relative root (by default) yields LookupError, fixes #419, #424, also related to #395

src/fs/loader.ts

@@ -16,14 +16,21 @@ export enum LookupType {
   Root = 'root'
 }
 export class Loader {
+  public shouldLoadRelative: (referencedFile: string) => boolean
   private options: LoaderOptions
-  private sep: string
-  private rRelativePath: RegExp
+  private contains: (root: string, file: string) => boolean
 
   constructor (options: LoaderOptions) {
     this.options = options
-    this.sep = this.options.fs.sep || '/'
-    this.rRelativePath = new RegExp(['.' + this.sep, '..' + this.sep].map(prefix => escapeRegex(prefix)).join('|'))
+    if (options.relativeReference) {
+      const sep = options.fs.sep
+      assert(sep, '`fs.sep` is required for relative reference')
+      const rRelativePath = new RegExp(['.' + sep, '..' + sep].map(prefix => escapeRegex(prefix)).join('|'))
+      this.shouldLoadRelative = (referencedFile: string) => rRelativePath.test(referencedFile)
+    } else {
+      this.shouldLoadRelative = (referencedFile: string) => false
+    }
+    this.contains = this.options.fs.contains || (() => true)
   }
 
   public * lookup (file: string, type: LookupType, sync?: boolean, currentFile?: string) {
@@ -35,16 +42,12 @@ export class Loader {
     throw this.lookupError(file, dirs)
   }
 
-  public shouldLoadRelative (referencedFile: string) {
-    return this.options.relativeReference && this.rRelativePath.test(referencedFile)
-  }
-
   public * candidates (file: string, dirs: string[], currentFile?: string, enforceRoot?: boolean) {
     const { fs, extname } = this.options
     if (this.shouldLoadRelative(file) && currentFile) {
       const referenced = fs.resolve(this.dirname(currentFile), file, extname)
       for (const dir of dirs) {
-        if (!enforceRoot || this.withinDir(referenced, dir)) {
+        if (!enforceRoot || this.contains(dir, referenced)) {
           // the relatively referenced file is within one of root dirs
           yield referenced
           break
@@ -53,7 +56,7 @@ export class Loader {
     }
     for (const dir of dirs) {
       const referenced = fs.resolve(dir, file, extname)
-      if (!enforceRoot || this.withinDir(referenced, dir)) {
+      if (!enforceRoot || this.contains(dir, referenced)) {
         yield referenced
       }
     }
@@ -63,11 +66,6 @@ export class Loader {
     }
   }
 
-  private withinDir (file: string, dir: string) {
-    dir = dir.endsWith(this.sep) ? dir : dir + this.sep
-    return file.startsWith(dir)
-  }
-
   private dirname (path: string) {
     const fs = this.options.fs
     assert(fs.dirname, '`fs.dirname` is required for relative reference')