blackify explicit waits chap

Author: hjwp

chapter_explicit_waits_1.asciidoc

@@ -132,12 +132,10 @@ class to make it use `LiveServerTestCase`:
 ----
 from django.test import LiveServerTestCase
 from selenium import webdriver
-from selenium.webdriver.common.keys import Keys
-import time
+[...]
 
 
 class NewVisitorTest(LiveServerTestCase):
-
     def setUp(self):
         [...]
 ----
@@ -177,9 +175,9 @@ FAIL: test_can_start_a_list_and_retrieve_it_later (functional_tests.tests.NewVi
 sitorTest.test_can_start_a_list_and_retrieve_it_later)
  ---------------------------------------------------------------------
 Traceback (most recent call last):
-  File "...python-tdd-book/functional_tests/tests.py", line 66, in
+  File "...python-tdd-book/functional_tests/tests.py", line 59, in
 test_can_start_a_list_and_retrieve_it_later
-    self.fail('Finish the test!')
+    self.fail("Finish the test!")
 AssertionError: Finish the test!
 
  ---------------------------------------------------------------------
@@ -334,7 +332,7 @@ talk about the `time.sleep` in our FT:
         inputbox.send_keys(Keys.ENTER)
         time.sleep(1)
 
-        self.check_for_row_in_list_table('1: Buy peacock feathers')
+        self.check_for_row_in_list_table("1: Buy peacock feathers")
 ----
 ====
 
@@ -382,30 +380,32 @@ polling/retry logic to it:
 ====
 [source,python]
 ----
+[...]
 from selenium.common.exceptions import WebDriverException
+import time
 
-MAX_WAIT = 10  #<1>
+MAX_WAIT = 5  # <1>
 [...]
 
     def wait_for_row_in_list_table(self, row_text):
         start_time = time.time()
-        while True:  #<2>
+        while True:  # <2>
             try:
-                table = self.browser.find_element(By.ID, 'id_list_table')  #<3>
-                rows = table.find_elements(By.TAG_NAME, 'tr')
+                table = self.browser.find_element(By.ID, "id_list_table")  # <3>
+                rows = table.find_elements(By.TAG_NAME, "tr")
                 self.assertIn(row_text, [row.text for row in rows])
-                return  #<4>
-            except (AssertionError, WebDriverException) as e:  #<5>
-                if time.time() - start_time > MAX_WAIT:  #<6>
-                    raise e  #<6>
-                time.sleep(0.5)  #<5>
+                return  # <4>
+            except (AssertionError, WebDriverException) as e:  # <5>
+                if time.time() - start_time > MAX_WAIT:  # <6>
+                    raise e  # <6>
+                time.sleep(0.5)  # <5>
 ----
 ====
 
 
-<1> We'll use a constant called `MAX_WAIT` to set the maximum
-    amount of time we're prepared to wait.  10 seconds should be more than
-    enough to catch any glitches or random slowness.
+<1> We'll use a constant called `MAX_WAIT`
+    to set the maximum amount of time we're prepared to wait.
+    5 seconds should be enough to catch any glitches or random slowness.
 
 <2> Here's the loop, which will keep going forever, unless we get to
     one of two possible exit routes.
@@ -429,8 +429,6 @@ MAX_WAIT = 10  #<1>
     our test, and most likely end up in our traceback, telling us why the test
     failed.
 
-//TODO: see if we can't reduce this down to eg 5s and still have reliable CI
-
 Are you thinking this code is a little ugly, and makes it a bit harder to see
 exactly what we're doing?  I agree. <<self.wait-for,Later on>>, we'll refactor
 out a general `wait_for` helper, to separate the timing and re-raising logic
@@ -456,18 +454,18 @@ Now we can rename our method calls, and remove the voodoo ++time.sleep++s:
     # When she hits enter, the page updates, and now the page lists
     # "1: Buy peacock feathers" as an item in a to-do list table
     inputbox.send_keys(Keys.ENTER)
-    self.wait_for_row_in_list_table('1: Buy peacock feathers')
+    self.wait_for_row_in_list_table("1: Buy peacock feathers")
 
-    # There is still a text box inviting her to add another item. She
-    # enters "Use peacock feathers to make a fly" (Edith is very
-    # methodical)
-    inputbox = self.browser.find_element(By.ID, 'id_new_item')
-    inputbox.send_keys('Use peacock feathers to make a fly')
+    # There is still a text box inviting her to add another item.
+    # She enters "Use peacock feathers to make a fly"
+    # (Edith is very methodical)
+    inputbox = self.browser.find_element(By.ID, "id_new_item")
+    inputbox.send_keys("Use peacock feathers to make a fly")
     inputbox.send_keys(Keys.ENTER)
 
     # The page updates again, and now shows both items on her list
-    self.wait_for_row_in_list_table('2: Use peacock feathers to make a fly')
-    self.wait_for_row_in_list_table('1: Buy peacock feathers')
+    self.wait_for_row_in_list_table("1: Buy peacock feathers")
+    self.wait_for_row_in_list_table("2: Use peacock feathers to make a fly")
     [...]
 ----
 ====
@@ -487,9 +485,9 @@ FAIL: test_can_start_a_list_and_retrieve_it_later (functional_tests.tests.NewVi
 sitorTest.test_can_start_a_list_and_retrieve_it_later)
  ---------------------------------------------------------------------
 Traceback (most recent call last):
-  File "...python-tdd-book/functional_tests/tests.py", line 74, in
+  File "...python-tdd-book/functional_tests/tests.py", line 68, in
 test_can_start_a_list_and_retrieve_it_later
-    self.fail('Finish the test!')
+    self.fail("Finish the test!")
 AssertionError: Finish the test!
 
  ---------------------------------------------------------------------
@@ -513,17 +511,17 @@ look for some row text that will never appear, we get the right error:
 ====
 [source,python]
 ----
-        rows = table.find_elements(By.TAG_NAME, 'tr')
-        self.assertIn('foo', [row.text for row in rows])
-        return
+    rows = table.find_elements(By.TAG_NAME, "tr")
+    self.assertIn("foo", [row.text for row in rows])
+    return
 ----
 ====
 
 We see we still get a nice self-explanatory test failure message:
 
 [subs="specialcharacters,macros"]
 ----
-    self.assertIn('foo', [row.text for row in rows])
+    self.assertIn("foo", [row.text for row in rows])
 AssertionError: 'foo' not found in ['1: Buy peacock feathers']
 ----
 
@@ -537,8 +535,8 @@ Let's put that back the way it was and break something else:
 [source,python]
 ----
     try:
-        table = self.browser.find_element(By.ID, 'id_nothing')
-        rows = table.find_elements(By.TAG_NAME, 'tr')
+        table = self.browser.find_element(By.ID, "id_nothing")
+        rows = table.find_elements(By.TAG_NAME, "tr")
         self.assertIn(row_text, [row.text for row in rows])
         return
     [...]