Re-work filtering and caching

* sx-auth.el
  - Use new symbolic cache access

* sx-cache.el
  - Implement symbolic cache access

* sx-filter.el
  - Use symbolic cache access
  - Compile and save filters on-demand
    (more work to be done to this end)

* sx-question.el
  - Symbolic filters

* sx-request.el
  - Protection against infinitely recursing when compiling a filter
    This will be re-worked into requests (a front-end function) and
    'raw' requests (a back-end function).  The front-end will add
    convenience to the back-end.

* test/tests.el
  Remove outdated tests

6 files changed, 36 insertions, 67 deletions

diff --git a/sx-auth.el b/sx-auth.el
index b23b448..049827d 100644
--- a/sx-auth.el
+++ b/sx-auth.el
@@ -65,7 +65,7 @@ questions)."
   (if (string-equal "" sx-auth-access-token)
       (progn (setq sx-auth-access-token nil)
              (error "You must enter this code to use this client fully"))
-    (sx-cache-set "auth.el" `((access-token . ,sx-auth-access-token)))))
+    (sx-cache-set 'auth `((access-token . ,sx-auth-access-token)))))
 
 (provide 'sx-auth)
 ;;; sx-auth.el ends here
diff --git a/sx-cache.el b/sx-cache.el
index a090982..54ae94f 100644
--- a/sx-cache.el
+++ b/sx-cache.el
@@ -20,7 +20,12 @@
 
 ;;; Commentary:
 
+;; All caches are retrieved and set using symbols.  The symbol should
+;; be the sub-subpackage that is using the cache.  For example,
+;; `sx-pkg' would use `(sx-cache-get 'pkg)'.
 ;;
+;; This symbol is then converted into a filename within
+;; `sx-cache-directory'.
 
 ;;; Code:
 
@@ -30,7 +35,9 @@
 
 (defun sx-cache-get-file-name (filename)
   "Expands FILENAME in the context of `sx-cache-directory'."
-  (expand-file-name filename sx-cache-directory))
+  (expand-file-name
+   (concat (symbol-name filename) ".el")
+   sx-cache-directory))
 
 (defun sx-cache-get (cache)
   "Return the data within CACHE.
diff --git a/sx-filter.el b/sx-filter.el
index 7178259..0ba8186 100644
--- a/sx-filter.el
+++ b/sx-filter.el
@@ -32,17 +32,9 @@
 
 ;;; Customizations
 
-(defconst sx-filter-cache-file
-  "filters.el")
-
-(defvar sx-filter
-  'default
-  "The current filter.
-To customize the filter for the next call to `sx-request-make',
-let-bind this variable to the output of a call to
-`sx-filter-compile'.  Be careful!  If you're going to be using
-this new filter a lot, create a variable for it.  Creation
-requests count against `sx-request-remaining-api-requests'!")
+(defvar sx--filter-alist
+  (sx-cache-get 'filter)
+  "")
 
 
 ;;; Compilation
@@ -67,32 +59,20 @@ or string."
 
 ;;; Storage and Retrieval
 
-(defun sx-filter-get (filter)
-  "Retrieve named FILTER from `sx-filter-cache-file'."
-  (cdr (assoc filter (sx-cache-get sx-filter-cache-file))))
-
-(defun sx-filter-store (name &optional filter)
-  "Store NAME as FILTER in `sx-filter-cache-file'.
-
-NAME should be a symbol and FILTER is a string as compiled by
-`sx-filter-compile'.
-
-If NAME is a cons cell, (car NAME) is taken to be the actual NAME
-and (cdr NAME) is taken to be the actual FILTER.  In this case,
-the second argument is simply ignored."
-  (let ((name   (if (consp name) (car name) name))
-        (filter (if (consp name) (cdr name) filter)))
-    (unless (symbolp name)
-      (error "Name must be a symbol: %S" name))
-    (let* ((dict (sx-cache-get sx-filter-cache-file))
-           (entry (assoc name dict)))
-      (if entry (setcdr entry filter)
-        (setq dict (cons (cons name filter) dict)))
-
-      (sx-cache-set sx-filter-cache-file dict))))
-
-(defun sx-filter-store-all (name-filter-alist)
-  (mapc #'sx-filter-store name-filter-alist))
+(defun sx-filter-get-var (filter-variable)
+  "Return the string representation of FILTER-VARIABLE."
+  (apply #'sx-filter-get filter-variable))
+
+(defun sx-filter-get (&optional include exclude base)
+  "Return the string representation of the given filter."
+  ;; Maybe we alreay have this filter
+  (or (cdr (assoc (list include exclude base) sx--filter-alist))
+      ;; If we don't, build it, save it, and return it.
+      (let ((filter (sx-filter-compile include exclude base)))
+        (when filter
+          (push (cons (list include exclude base) filter) sx--filter-alist)
+          (sx-cache-set 'filter sx--filter-alist)
+          filter))))
 
 (provide 'sx-filter)
 ;;; sx-filter.el ends here
diff --git a/sx-question.el b/sx-question.el
index 0ce5413..8957e6f 100644
--- a/sx-question.el
+++ b/sx-question.el
@@ -30,12 +30,9 @@
 (require 'sx-request)
 
 ;; I don't know why this is here, but it was causing an API request on require.
-(defvar sx-question-browse-filter nil)
-(sx-init-variable
- sx-question-browse-filter
- (sx-filter-compile nil '(user.profile_image shallow_user.profile_image)))
-
-;; (stack-filter-store 'question-browse sx-question-browse-filter)
+(defvar sx-question-browse-filter
+  ;; Remember: INCLUDE EXCLUDE BASE
+  '(nil (user.profile_image shallow_user.profile_image)))
 
 (defun sx-question-get-questions (site &optional page)
   "Get the page PAGE of questions from SITE."
diff --git a/sx-request.el b/sx-request.el
index a62ee0e..8ca0314 100644
--- a/sx-request.el
+++ b/sx-request.el
@@ -26,6 +26,7 @@
 (require 'json)
 (require 'url)
 (require 'sx)
+(require 'sx-filter)
 
 (defcustom sx-request-silent-p
   t
@@ -95,8 +96,11 @@ entire response as a complex alist."
 	(call
 	 (sx-request--build
 	  method
-	  (append `((filter . ,(cond (filter filter)
-                                     ((boundp 'stack-filter) stack-filter)))
+	  (append `((filter . ,(unless (string-equal method "filter/create")
+                                 (sx-filter-get-var
+                                  (cond (filter filter)
+                                        ((boundp 'stack-filter)
+                                         stack-filter)))))
                     (key . ,sx-request-api-key))
 		(if keyword-arguments keyword-arguments
 		  (sx-request--get-default-keyword-arguments method))))))
diff --git a/test/tests.el b/test/tests.el
index c7861d8..7915ac0 100644
--- a/test/tests.el
+++ b/test/tests.el
@@ -9,8 +9,7 @@
 (defvar sx-test-data-dir
   (expand-file-name
    "data-samples/"
-   (or (file-name-directory load-file-name) "./"))
-  "")
+   (or (file-name-directory load-file-name) "./")))
 
 (defun sx-test-sample-data (method &optional directory)
   (let ((file (concat (when directory (concat directory "/"))
@@ -89,24 +88,6 @@
                       ((1 . alpha) (2 . beta))]
                      '(1 2 3)))))
 
-(ert-deftest test-filters ()
-  (let ((stack-cache-directory (make-temp-file "stack-test" t)))
-    (should-error (sx-filter-store "names must be symbols"
-                                   "this is a filter"))
-    ;; basic use
-    (should (equal '((test . "filter"))
-                   (sx-filter-store 'test "filter")))
-    ;; aggregation
-    (should (equal '((test2 . "filter2") (test . "filter"))
-                   (sx-filter-store 'test2 "filter2")))
-    ;; mutation
-    (should (equal '((test2 . "filter2") (test . "filter-test"))
-                   (sx-filter-store 'test "filter-test")))
-    ;; clean up (note: the file should exist)
-    (delete-file
-     (sx-cache-get-file-name
-      sx-filter-cache-file))))
-
 (defmacro line-should-match (regexp)
   ""
   `(let ((line (buffer-substring-no-properties