Use list_find in more places and refactor/fix workspace prev_next functions

The original purpose of this commit is to replace some for loops with
list_find. But while doing this I found the workspace_prev_next_impl
functions to be difficult to read and also contained a bug, so I
refactored them and fixed the bug.

To reproduce the bug:

* Have two outputs, where the left output has workspaces 1, 2, 3 and the
right output has workspaces 4, 5, 6. Make workspace 2 focused_inactive
and workspace 4 focused.
* Run `workspace prev`.
* Previously it would visit the left output, then apply `workspace prev`
to workspace 2, which focuses workspace 1.
* Now it will focus the rightmost workspace on the left output
(workspace 3).

The refactoring I made to the workspace functions are:

* Added the static keyword.
* They now accept an int dir rather than bool, to avoid an unnecessary
conversion.
* Rather than preparing start and end variables for the purpose of
iterating, just iterate everything.
* Replace for loops with list_find.
* Don't call workspace_output_prev_next_impl (this fixes the bug).

1 files changed, 3 insertions, 5 deletions

diff --git a/sway/tree/root.c b/sway/tree/root.c
index 79f2194e..a974a461 100644
--- a/sway/tree/root.c
+++ b/sway/tree/root.c
@@ -84,11 +84,9 @@ void root_scratchpad_remove_container(struct sway_container *con) {
                 return;
         }
         con->scratchpad = false;
-        for (int i = 0; i < root_container.sway_root->scratchpad->length; ++i) {
-                if (root_container.sway_root->scratchpad->items[i] == con) {
-                        list_del(root_container.sway_root->scratchpad, i);
-                        break;
-                }
+        int index = list_find(root_container.sway_root->scratchpad, con);
+        if (index != -1) {
+                list_del(root_container.sway_root->scratchpad, index);
         }
 }