fix: handle unicode filename and website uploads (#491)

* fix: print meaningful error message for invalid filenames

* fix: handle unicode dirnames and filenames

* chore: revert custom error message

ui-test/test-case/UnicodeWebsiteUpload.js

@@ -0,0 +1,16 @@
+const puppeteer = require('puppeteer')
+const { selectStampAndUpload, assertUploadedContentAtPath } = require('../helpers')
+const { Click } = require('../library')
+
+/**
+ * @param {puppeteer.Page} page Puppeteer Page object returned by `browser.newPage()`
+ */
+async function testUnicodeWebsiteUpload(page) {
+  await Click.elementWithText(page, 'a', 'Files')
+  await Click.elementWithTextAndUpload(page, 'button', 'Add Website', 'test-data/test-unicode-website—𝖆𝖆🙇\\𝖈𝖈')
+  const swarmHash = await selectStampAndUpload(page)
+  await assertUploadedContentAtPath(swarmHash, 'index.html', 'text/html; charset=utf-8')
+  await assertUploadedContentAtPath(swarmHash, '—𝖆𝖆🙇/𝖈𝖈.txt', 'text/plain; charset=utf-8')
+}
+
+module.exports = { testUnicodeWebsiteUpload }