Switching to a specific layout interferes with cycling over layouts

[qsmodo]

awesome v4.3 (Too long)
 • Compiled against Lua 5.1.5 (running with Lua 5.1)
 • D-Bus support: ✘
 • execinfo support: ✔
 • xcb-randr version: 1.6
 • LGI version: 0.9.2

How to reproduce the issue:

Modify lua.rc to only cycle over a subset of the available layouts with Mod+Space. Then assign a keybinding to a layout that is not in that subset. Example:

awful.layout.layouts = {
    awful.layout.suit.tile,
    awful.layout.suit.max,
}

-- Keys section
    awful.key({ modkey, }, "space", function () awful.layout.inc( 1) end,
              {description = "select next", group = "layout"}),
    awful.key({ modkey, }, "s", function () awful.layout.set(awful.layout.suit.tile.bottom) end,
              {description = "select previous", group = "layout"}),

Actual result:

Once you switch to the outsider layout with Mod+S, Mod+Space cycles over that layout too. If, on the other hand, you use awful.layout.inc( 1, nil, awful.layout.layouts) for Mod+Space, once you switch to the outsider layout with Mod+S, Mod+Space no longer cycles over any layout.

Expected result:

Mod+Space cycles over only layouts in awful.layout.layouts, always.

[Aire-One]

When setting the tag layout to a layout that is not in the tag's layouts table, the new layout is pushed to this tag layouts table.

awesome/lib/awful/layout/init.lua

Lines 143 to 144 in 13cd207

	local newindex = gmath.cycle(#layouts, cur_idx + i)
	layout.set(layouts[newindex], t)

So at the next call of layout.inc, the t.layout table contains the newly added layout, and the function will eventually iterate over it:

awesome/lib/awful/layout/init.lua

Line 119 in 13cd207

layouts = layouts or t.layouts or {}

This is an old behavior (> 3 years), so I wouldn't consider that as a bug, and I don't think any change should be applied. Maybe we can add a note about that in the documentation, tho?

So, I'm sorry to tell you that, but from my point of view, we shouldn't change any behavior. Instead, you have to adapt your code with the solution you proposed awful.layout.inc( 1, nil, awful.layout.layouts).

[actionless]

1. get current layout index: file:///usr/share/doc/awesome/doc/libraries/awful.layout.html#awful.layout.get_tag_layout_index
2. find index of desired layout: file:///usr/share/doc/awesome/doc/libraries/awful.layout.html#awful.layout.layouts
3. apply the difference between these two values: file:///usr/share/doc/awesome/doc/libraries/awful.layout.html#awful.layout.inc