[#23019867] At this point, a supporter can change the pledge amount to a smaller amount (no new PayPal transaction required) or a larger amount (a new PayPal transaction is required and the old transaction is canceled.)

I've not implemented the storage of the premium yet -- that's coming next.
I've not implemented straight out cancellation of a pledge yet.
More UI refinement needed, especially around encouraging supporters not to decrease (or cancel) a pledge and refinements to help people know that they have made a modification.

payment/tests.py

@@ -90,10 +90,12 @@ def paySandbox(test, selenium, url, authorize=False, already_at_url=False, sleep
 
         email_element = WebDriverWait(selenium, 60).until(lambda d : d.find_element_by_id("login_email"))
         email_element.click()
+        email_element.clear()
         email_element.send_keys(settings.PAYPAL_BUYER_LOGIN)
         
         password_element = WebDriverWait(selenium, 60).until(lambda d : d.find_element_by_id("login_password"))
         password_element.click()
+        password_element.clear()
         password_element.send_keys(settings.PAYPAL_BUYER_PASSWORD)
 
         submit_button = WebDriverWait(selenium, 60).until(lambda d : d.find_element_by_id("submitLogin"))

test/campaigntest.py

@@ -246,14 +246,28 @@ def support_campaign():
     change_pledge_button = WebDriverWait(sel,20).until(lambda d: d.find_element_by_css_selector("input[value*='Change Pledge']"))
     change_pledge_button.click()
     
-    # enter a new pledge
+    # enter a new pledge, which is less than the previous amount and therefore doesn't require a new PayPal transaction
     preapproval_amount_input = WebDriverWait(sel,20).until(lambda d: d.find_element_by_css_selector("input#id_preapproval_amount"))
     preapproval_amount_input.clear()  # get rid of existing pledge
     preapproval_amount_input.send_keys("5")
     pledge_button = WebDriverWait(sel,20).until(lambda d: d.find_element_by_css_selector("input[value*='Modify Pledge']"))
     pledge_button.click()
     
-    # 
+    # return to the Work page again
+    work_url = WebDriverWait(sel,20).until(lambda d: d.find_element_by_css_selector('p > a[href*="/work/"]'))
+    work_url.click()
+    change_pledge_button = WebDriverWait(sel,20).until(lambda d: d.find_element_by_css_selector("input[value*='Change Pledge']"))
+    change_pledge_button.click()
+
+    # enter a new pledge, which is less than the previous amount and therefore doesn't require a new PayPal transaction
+    preapproval_amount_input = WebDriverWait(sel,20).until(lambda d: d.find_element_by_css_selector("input#id_preapproval_amount"))
+    preapproval_amount_input.clear()  # get rid of existing pledge
+    preapproval_amount_input.send_keys("25")
+    pledge_button = WebDriverWait(sel,20).until(lambda d: d.find_element_by_css_selector("input[value*='Modify Pledge']"))
+    pledge_button.click()
+    paySandbox(None, sel, sel.current_url, authorize=True, already_at_url=True, sleep_time=5)
+    
+    print pm.checkStatus()
     
     return sel
     #sel.quit()