;;; eww-tests.el --- tests for eww.el -*- lexical-binding: t; -*-
;; Copyright (C) 2024-2025 Free Software Foundation, Inc.
;; This file is part of GNU Emacs.
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;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation, either version 3 of the License, or
;; (at your option) any later version.
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;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
;; GNU General Public License for more details.
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;;; Commentary:
;;; Code:
(require 'ert)
(require 'eww)
(defvar eww-test--response-function (lambda (url) (concat "\n" url))
"A function for returning a mock response for URL.
The default just returns an empty list of headers and the URL as the
body.")
(defmacro eww-test--with-mock-retrieve (&rest body)
"Evaluate BODY with a mock implementation of `eww-retrieve'.
This avoids network requests during our tests. Additionally, prepare a
temporary EWW buffer for our tests."
(declare (indent 0))
`(cl-letf (((symbol-function 'eww-retrieve)
(lambda (url callback args)
(with-temp-buffer
(insert (funcall eww-test--response-function url))
(apply callback nil args)))))
(with-temp-buffer
(eww-mode)
,@body)))
(defun eww-test--history-urls ()
(mapcar (lambda (elem) (plist-get elem :url)) eww-history))
;;; Tests:
(ert-deftest eww-test/display/html ()
"Test displaying a simple HTML page."
(skip-unless (libxml-available-p))
(eww-test--with-mock-retrieve
(let ((eww-test--response-function
(lambda (url)
(concat "Content-Type: text/html\n\n"
(format "Hello
%s"
url)))))
(eww "example.invalid")
;; Check that the buffer contains the rendered HTML.
(should (equal (buffer-string) "Hello\n\n\nhttp://example.invalid/\n"))
(should (equal (get-text-property (point-min) 'face)
'(shr-text shr-h1)))
;; Check that the DOM includes the `base'.
(should (equal (pcase (plist-get eww-data :dom)
(`(base ((href . ,url)) ,_) url))
"http://example.invalid/")))))
(ert-deftest eww-test/history/new-page ()
"Test that when visiting a new page, the previous one goes into the history."
(eww-test--with-mock-retrieve
(eww "one.invalid")
(eww "two.invalid")
(should (equal (eww-test--history-urls)
'("http://one.invalid/")))
(eww "three.invalid")
(should (equal (eww-test--history-urls)
'("http://two.invalid/"
"http://one.invalid/")))))
(ert-deftest eww-test/history/back-forward ()
"Test that navigating through history just changes our history position.
See bug#69232."
(eww-test--with-mock-retrieve
(eww "one.invalid")
(eww "two.invalid")
(eww "three.invalid")
(let ((url-history '("http://three.invalid/"
"http://two.invalid/"
"http://one.invalid/")))
;; Go back one page. This should add "three.invalid" to the
;; history, making our position in the list 2.
(eww-back-url)
(should (equal (eww-test--history-urls) url-history))
(should (= eww-history-position 2))
;; Go back again.
(eww-back-url)
(should (equal (eww-test--history-urls) url-history))
(should (= eww-history-position 3))
;; At the beginning of the history, so trying to go back should
;; signal an error.
(should-error (eww-back-url))
;; Go forward once.
(eww-forward-url)
(should (equal (eww-test--history-urls) url-history))
(should (= eww-history-position 2))
;; Go forward again.
(eww-forward-url)
(should (equal (eww-test--history-urls) url-history))
(should (= eww-history-position 1))
;; At the end of the history, so trying to go forward should
;; signal an error.
(should-error (eww-forward-url)))))
(ert-deftest eww-test/history/reload-in-place ()
"Test that reloading historical pages updates their history entry in-place.
See bug#69232."
(eww-test--with-mock-retrieve
(eww "one.invalid")
(eww "two.invalid")
(eww "three.invalid")
(eww-back-url)
;; Make sure our history has the original page text.
(should (equal (plist-get (nth 1 eww-history) :text)
"http://two.invalid/"))
(should (= eww-history-position 2))
;; Reload the page.
(let ((eww-test--response-function
(lambda (url) (concat "\nreloaded " url))))
(eww-reload)
(should (= eww-history-position 2)))
;; Go to another page, and make sure the history is correct,
;; including the reloaded page text.
(eww "four.invalid")
(should (equal (eww-test--history-urls) '("http://two.invalid/"
"http://one.invalid/")))
(should (equal (plist-get (nth 0 eww-history) :text)
"reloaded http://two.invalid/"))
(should (= eww-history-position 0))))
(ert-deftest eww-test/history/before-navigate/delete-future-history ()
"Test that going to a new page from a historical one deletes future history.
See bug#69232."
(eww-test--with-mock-retrieve
(eww "one.invalid")
(eww "two.invalid")
(eww "three.invalid")
(eww-back-url)
(eww "four.invalid")
(eww "five.invalid")
(should (equal (eww-test--history-urls) '("http://four.invalid/"
"http://two.invalid/"
"http://one.invalid/")))
(should (= eww-history-position 0))))
(ert-deftest eww-test/history/before-navigate/ignore-history ()
"Test that going to a new page from a historical one preserves history.
This sets `eww-before-browse-history-function' to `ignore' to preserve
history. See bug#69232."
(let ((eww-before-browse-history-function #'ignore))
(eww-test--with-mock-retrieve
(eww "one.invalid")
(eww "two.invalid")
(eww "three.invalid")
(eww-back-url)
(eww "four.invalid")
(eww "five.invalid")
(should (equal (eww-test--history-urls) '("http://four.invalid/"
"http://three.invalid/"
"http://two.invalid/"
"http://one.invalid/")))
(should (= eww-history-position 0)))))
(ert-deftest eww-test/history/before-navigate/clone-previous ()
"Test that going to a new page from a historical one clones prior history.
This sets `eww-before-browse-history-function' to
`eww-clone-previous-history' to clone the history. See bug#69232."
(let ((eww-before-browse-history-function #'eww-clone-previous-history))
(eww-test--with-mock-retrieve
(eww "one.invalid")
(eww "two.invalid")
(eww "three.invalid")
(eww-back-url)
(eww "four.invalid")
(eww "five.invalid")
(should (equal (eww-test--history-urls)
'(;; New page and cloned history.
"http://four.invalid/"
"http://two.invalid/"
"http://one.invalid/"
;; Original history.
"http://three.invalid/"
"http://two.invalid/"
"http://one.invalid/")))
(should (= eww-history-position 0)))))
(ert-deftest eww-test/readable/toggle-display ()
"Test toggling the display of the \"readable\" parts of a web page."
(skip-unless (libxml-available-p))
(eww-test--with-mock-retrieve
(let* ((shr-width most-positive-fixnum)
(shr-use-fonts nil)
(words (string-join
(make-list
20 "All work and no play makes Jack a dull boy.")
" "))
(eww-test--response-function
(lambda (_url)
(concat "Content-Type: text/html\n\n"
""
"This is an uninteresting sentence."
""
words
"
"
""))))
(eww "example.invalid")
;; Make sure EWW renders the whole document.
(should-not (plist-get eww-data :readable))
(should (string-prefix-p
"This is an uninteresting sentence."
(buffer-substring-no-properties (point-min) (point-max))))
(eww-readable 'toggle)
;; Now, EWW should render just the "readable" parts.
(should (plist-get eww-data :readable))
(should (string-match-p
(concat "\\`" (regexp-quote words) "\n*\\'")
(buffer-substring-no-properties (point-min) (point-max))))
(eww-readable 'toggle)
;; Finally, EWW should render the whole document again.
(should-not (plist-get eww-data :readable))
(should (string-prefix-p
"This is an uninteresting sentence."
(buffer-substring-no-properties (point-min) (point-max)))))))
(ert-deftest eww-test/readable/default-readable ()
"Test that EWW displays readable parts of pages by default when applicable."
(skip-unless (libxml-available-p))
(eww-test--with-mock-retrieve
(let* ((eww-test--response-function
(lambda (_url)
(concat "Content-Type: text/html\n\n"
"Hello there")))
(eww-readable-urls '("://example\\.invalid/")))
(eww "example.invalid")
;; Make sure EWW uses "readable" mode.
(should (plist-get eww-data :readable)))))
(provide 'eww-tests)
;; eww-tests.el ends here