[cl-selenium-devel] Problems with cl-selenium, Drakma, and nasty JavaScript

[Robin Lee Powell]

I just moved over from Scheme, and am trying to get my project,
which is TDD-via-Selenium based, ported over.  Mostly going well;
thank you for saving me the trouble of creating a Selenium port.
Again.

The problem I'm having is with a function I wrote to retrieve CSS
properties of page elements; I like to be able to check that things
are being rendered properly.  As far as I know, there's nothing for
this in the Selenium API.

Here's the function.  It's horrible; I apologize.

- ------------------

; Takes an element locator and a CSS property name, and returns the
; value for that property on that locator.
;
; Example:
;
; (expect-string= "And: the ephemeral bit is bolded."
;                 "bold"
;                 (element-attribute hpv "Num Ratings Text Ephemera" "font-weight"))
;
; The Javascript here is a bit scary.
(defun element-css-raw (elem prop)
  (let* (
         ; Some browsers want font-family; some want fontFamily.
         ;
         ; *sigh*
         (prop-lis (cl-ppcre:split "[-]" prop))
         (camel-prop (apply #'concatenate 'string
                            (cons (car prop-lis) (mapcar #'(lambda (x) (string-capitalize x)) (cdr prop-lis)))))
         ; The actual javascript
         (js
           (format
             nil
             (concatenate 'string
               "element = this.page().findElement(\"~A\"); "
               "if( element.currentStyle ) "
               "{ element.currentStyle.~A } "
               "else { this.browserbot.getCurrentWindow()."
               "getComputedStyle( element, null )."
               "getPropertyValue('~A') }")
             elem
             camel-prop
             prop))
         ; Running the javascript
         (js-out (do-get-eval js))
         ; Some browers think colours look like rgb( rrr, ggg, bbb )
         ; (where all are decimal numbers), but we prefer #rrggbb,
         ; so we make it that way
         (color-normalized-js-out
           (cond
             ((cl-ppcre:scan "^\\s*rgb\\(" js-out)
              (apply format nil "#~2,'0X~2,'0X~2,'0X"
                     (map
                       (lambda (num-str) (parse-integer num-str))
                       (cl-ppcre:split
                         ", *"
                         (cl-ppcre:regex-replace
                           "\\)$"
                           (cl-ppcre:regex-replace "^\\s*rgb\\(" js-out "")
                           "")))))
             (t js-out)))
         )
    ;(format #t "element-css: ~A, ~A, ~A, ~A, ~A\n" elem prop camel-prop js color-normalized-js-out)
    color-normalized-js-out))

- ------------------

The problem is with "element = this.page().findElement(\"~A\"); "

Specifically, the embedded ".

Drakma simply won't accept them:

  Parse error:URI "http://localhost:4444/selenium-server/driver/?cmd=getEval&1=element%20%3D%20this.page().findElement(\"id%3Dhome\")%3B%20if(%20element.currentStyle%20)%20%7B%20element.currentStyle.textDecoration%20%7D%20else%20%7B%20this.browserbot.getCurrentWindow().getComputedStyle(%20element,%20null%20).getPropertyValue('text-decoration')%20%7D&sessionId=821656" contains illegal character #\" at position 100.

The obvious solution of replacing them with ' doesn't work, because
some of my xpaths have ' in them, so that fails entirely.  I can't
just replace the ' in the xpaths with " to make up for *that*,
because if I do, the " still end up in the Drakma request, and again
Drakma refuses.

I haven't started hacking source for cl-selenium for Drakma yet; any
help would be appreciated.

-Robin

-- 
Lojban Reason #17: http://en.wikipedia.org/wiki/Buffalo_buffalo
Proud Supporter of the Singularity Institute - http://singinst.org/
http://www.digitalkingdom.org/~rlpowell/ *** http://www.lojban.org/