[Fix #2294] simplify stacktrace filter mechanism

previously there were two separate lists of positive and negative
filters and complicated logic spread throughout of how these
interacted. Now there is a single list that you can toggle flags on or
off and their interaction is dictated inside of a single function
`cider-stacktrace-apply-filters`. Since their interaction is here we
no longer need to remember previous flags as they are just toggled on
and off.

Positive filters are 'all or 'project. These dictate that all frames
should be shown or only any frame from a project namespace should be
shown, despite other filters. Also, these two cannot exist at the same
time, so we need to check which is most "recent". Since if 'project is
selected, it hides all but project frames and if 'all is selected it
must show all. We do what was most recently selected in this case
then.

So the frame filtering is quite simply a list of tags you want to
filter by: '(java clj tooling repl dup project all). These are toggled
on and off as desired.

1 files changed, 46 insertions, 45 deletions

diff --git a/cider-stacktrace.el b/cider-stacktrace.el
index c8ebb7ee..929f54b3 100644
--- a/cider-stacktrace.el
+++ b/cider-stacktrace.el
@@ -89,7 +89,6 @@ cyclical data structures."
 
 (defvar-local cider-stacktrace-hidden-frame-count 0)
 (defvar-local cider-stacktrace-filters nil)
-(defvar-local cider-stacktrace-prior-filters nil)
 (defvar-local cider-stacktrace-cause-visibility nil)
 (defvar-local cider-stacktrace-positive-filters nil)
 
@@ -225,7 +224,7 @@ The error types are represented as strings."
         ["Show/hide REPL frames" cider-stacktrace-toggle-repl]
         ["Show/hide tooling frames" cider-stacktrace-toggle-tooling]
         ["Show/hide duplicate frames" cider-stacktrace-toggle-duplicates]
-        ["Show only project frames" cider-stacktrace-show-only-project]
+        ["Toggle only project frames" cider-stacktrace-show-only-project]
         ["Show/hide all frames" cider-stacktrace-toggle-all]))
     map))
 
@@ -236,7 +235,6 @@ The error types are represented as strings."
   (when cider-special-mode-truncate-lines
     (setq-local truncate-lines t))
   (setq-local electric-indent-chars nil)
-  (setq-local cider-stacktrace-prior-filters nil)
   (setq-local cider-stacktrace-hidden-frame-count 0)
   (setq-local cider-stacktrace-filters cider-stacktrace-default-filters)
   (setq-local cider-stacktrace-cause-visibility (make-vector 10 0)))
@@ -249,7 +247,7 @@ The error types are represented as strings."
   "Filters that remove stackframes.")
 
 (defvar cider-stacktrace--all-positive-filters
-  '(project)
+  '(project all)
   "Filters that ensure stackframes are shown.")
 
 (defun cider-stacktrace--face-for-filter (filter neg-filters pos-filters)
@@ -266,10 +264,6 @@ override this and ensure that those frames are shown."
         ((member filter cider-stacktrace--all-positive-filters)
          (if (member filter pos-filters)
              'cider-stacktrace-filter-active-face
-           'cider-stacktrace-filter-inactive-face))
-        ((null filter)                               ; "all" filter
-         (if (null neg-filters)
-             'cider-stacktrace-filter-active-face
            'cider-stacktrace-filter-inactive-face))))
 
 (defun cider-stacktrace-indicate-filters (filters pos-filters)
@@ -315,18 +309,22 @@ NEG-FILTERS dictate which frames should be hidden while POS-FILTERS can
 override this and ensure that those frames are shown.
 Argument FLAGS are the flags set on the stackframe, ie: clj dup, etc."
   (let ((neg (seq-intersection neg-filters flags))
-        (pos (seq-intersection pos-filters flags)))
-    (cond ((and pos neg) nil)
+        (pos (seq-intersection pos-filters flags))
+        (all (memq 'all pos-filters)))
+    (cond (all nil) ;; if all filter is on then we should not hide
+          ((and pos neg) nil) ;; if hidden and "resurrected" we should not hide
           (pos nil)
           (neg t)
           (t nil))))
 
-(defun cider-stacktrace-apply-filters (neg-filters pos-filters)
+(defun cider-stacktrace--apply-filters (neg-filters pos-filters)
   "Set visibility on stack frames.
-Update `cider-stacktrace-hidden-frame-count' and indicate filters applied.
-Currently collapsed stacktraces are ignored, and do not contribute to the
-hidden count.  NEG-FILTERS remove frames with the flag in that list and
-POS-FILTERS ensure that frames with flag is shown."
+Should be called by `cider-stacktrace-apply-filters' which has the logic of
+how to interpret the combinations of the positive and negative filters.
+For instance, the presence of the positive filter `project' requires all of
+the other negative filters to be applied so that only project frames are
+shown.  NEG-FILTERS are the tags that should be hidden.  POS-FILTERS are
+the tags that must be shown."
   (with-current-buffer cider-error-buffer
     (save-excursion
       (goto-char (point-min))
@@ -346,6 +344,29 @@ POS-FILTERS ensure that frames with flag is shown."
         (setq cider-stacktrace-hidden-frame-count hidden)))
     (cider-stacktrace-indicate-filters neg-filters pos-filters)))
 
+(defun cider-stacktrace-apply-filters (filters)
+  "Takes a single list of filters and applies them.
+Update `cider-stacktrace-hidden-frame-count' and indicate
+filters applied.  Currently collapsed stacktraces are ignored, and do not
+contribute to the hidden count.  FILTERS is the list of filters to be
+applied, positive and negative all together.  This function defines how
+those choices interact and separates them into positive and negative
+filters for the resulting machinery."
+  (let ((neg-filters (seq-intersection filters cider-stacktrace--all-negative-filters))
+        (pos-filters (seq-intersection filters cider-stacktrace--all-positive-filters)))
+    ;; project and all are mutually exclusive. when both are present we check to
+    ;; see the most recent one (as cons onto the list would put it) and use that
+    ;; interaction.
+    (cond
+     ((memq 'all (memq 'project pos-filters)) ;; project is most recent
+      (cider-stacktrace--apply-filters cider-stacktrace--all-negative-filters '(project)))
+     ((memq 'project (memq 'all pos-filters)) ;; all is most recent
+      (cider-stacktrace--apply-filters nil '(all)))
+     ((memq 'all pos-filters) (cider-stacktrace--apply-filters nil '(all)))
+     ((memq 'project pos-filters) (cider-stacktrace--apply-filters cider-stacktrace--all-negative-filters
+                                                                   pos-filters))
+     (t (cider-stacktrace--apply-filters neg-filters pos-filters)))))
+
 (defun cider-stacktrace-apply-cause-visibility ()
   "Apply `cider-stacktrace-cause-visibility' to causes and reapply filters."
   (with-current-buffer cider-error-buffer
@@ -369,8 +390,7 @@ POS-FILTERS ensure that frames with flag is shown."
                   (add-text-properties (point) detail-end
                                        (list 'invisible hide
                                              'collapsed hide))))))))
-      (cider-stacktrace-apply-filters cider-stacktrace-filters
-                                      cider-stacktrace-positive-filters))))
+      (cider-stacktrace-apply-filters cider-stacktrace-filters))))
 
 ;;; Internal/Middleware error suppression
 
@@ -469,42 +489,23 @@ When it reaches 3, it wraps to 0."
   (interactive)
   (cider-stacktrace-cycle-cause 5))
 
-(defun cider-stacktrace-toggle-all ()
-  "Reset `cider-stacktrace-filters' if present; otherwise restore prior filters."
-  (interactive)
-  (when cider-stacktrace-filters
-    (setq-local cider-stacktrace-prior-filters
-                cider-stacktrace-filters))
-  (cider-stacktrace-apply-filters
-   (setq cider-stacktrace-filters
-         (unless cider-stacktrace-filters      ; when current filters are nil,
-           cider-stacktrace-prior-filters))    ; reenable prior filter set
-   cider-stacktrace-positive-filters))
-
 (defun cider-stacktrace-toggle (flag)
   "Update `cider-stacktrace-filters' to add or remove FLAG, and apply filters."
   (cider-stacktrace-apply-filters
    (setq cider-stacktrace-filters
          (if (memq flag cider-stacktrace-filters)
              (remq flag cider-stacktrace-filters)
-           (cons flag cider-stacktrace-filters)))
-   cider-stacktrace-positive-filters))
+           (cons flag cider-stacktrace-filters)))))
+
+(defun cider-stacktrace-toggle-all ()
+  "Toggle `all' in filter list."
+  (interactive)
+  (cider-stacktrace-toggle 'all))
 
 (defun cider-stacktrace-show-only-project ()
-  "Display only the stackframes from the project.
-BUTTON is the button at the top of the error buffer as the button calls
-with the button."
+  "Display only the stackframes from the project."
   (interactive)
-  (if (null cider-stacktrace-positive-filters)
-      (progn
-        (setq-local cider-stacktrace-prior-filters cider-stacktrace-filters)
-        (setq-local cider-stacktrace-filters cider-stacktrace--all-negative-filters)
-        (setq-local cider-stacktrace-positive-filters '(project)))
-    (progn
-      (setq-local cider-stacktrace-filters cider-stacktrace-prior-filters)
-      (setq-local cider-stacktrace-positive-filters nil)))
-  (cider-stacktrace-apply-filters cider-stacktrace-filters
-                                  cider-stacktrace-positive-filters))
+  (cider-stacktrace-toggle 'project))
 
 (defun cider-stacktrace-toggle-java ()
   "Toggle display of Java stack frames."
@@ -874,7 +875,7 @@ through the `cider-stacktrace-suppressed-errors' variable."
       ;; Stacktrace filters
       (cider-stacktrace-render-filters
        buffer
-       `(("Project-Only" project) ("All" ,nil))
+       `(("Project-Only" project) ("All" all))
        `(("Clojure" clj) ("Java" java) ("REPL" repl)
          ("Tooling" tooling) ("Duplicates" dup)))
       (insert "\n")