add hw2

node_modules/bare-fs/lib/errors.js

@@ -0,0 +1,61 @@
+const os = require('bare-os')
+
+module.exports = class FileError extends Error {
+  constructor(msg, opts = {}) {
+    const {
+      code,
+      operation = null,
+      path = null,
+      destination = null,
+      fd = -1
+    } = opts
+
+    if (operation !== null) msg += describe(operation, opts)
+
+    super(`${code}: ${msg}`)
+
+    this.code = code
+
+    if (operation !== null) this.operation = operation
+    if (path !== null) this.path = path
+    if (destination !== null) this.destination = destination
+    if (fd !== -1) this.fd = fd
+  }
+
+  get name() {
+    return 'FileError'
+  }
+
+  // For Node.js compatibility
+  get errno() {
+    return os.constants.errnos[this.code]
+  }
+
+  // For Node.js compatibility
+  get syscall() {
+    return this.operation
+  }
+
+  // For Node.js compatibility
+  get dest() {
+    return this.destination
+  }
+}
+
+function describe(operation, opts) {
+  const { path = null, destination = null, fd = -1 } = opts
+
+  let result = `, ${operation}`
+
+  if (path !== null) {
+    result += ` ${JSON.stringify(path)}`
+
+    if (destination !== null) {
+      result += ` -> ${JSON.stringify(destination)}`
+    }
+  } else if (fd !== -1) {
+    result += ` ${fd}`
+  }
+
+  return result
+}