diff --git a/tests/examples/awful/template.lua b/tests/examples/awful/template.lua
index 75c4feec..aa79ff09 100644
--- a/tests/examples/awful/template.lua
+++ b/tests/examples/awful/template.lua
@@ -35,8 +35,8 @@ local function draw_mouse(x, y)
 end
 
 -- Print an outline for the screens
-if not screen.no_outline then
-    for _, s in ipairs(screen) do
+if not rawget(screen, "no_outline") then
+    for s in screen do
         cr:save()
         -- Draw the screen outline
         cr:set_source(color("#00000044"))
diff --git a/tests/examples/shims/awesome.lua b/tests/examples/shims/awesome.lua
index 3e97847a..24272af5 100644
--- a/tests/examples/shims/awesome.lua
+++ b/tests/examples/shims/awesome.lua
@@ -75,6 +75,10 @@ function awesome.pixbuf_to_surface(_, path)
     return awesome.load_image(path)
 end
 
+function awesome.xrdb_get_value()
+    return nil
+end
+
 -- Always show deprecated messages
 awesome.version = "v9999"
 
diff --git a/tests/examples/shims/client.lua b/tests/examples/shims/client.lua
index bf76a426..c65e3d03 100644
--- a/tests/examples/shims/client.lua
+++ b/tests/examples/shims/client.lua
@@ -22,6 +22,45 @@ local function titlebar_meta(c)
     end
 end
 
+local properties = {}
+
+-- Emit the request::geometry signal to make immobilized and awful.ewmh work.
+for _, prop in ipairs {
+  "maximized", "maximized_horizontal", "maximized_vertical", "fullscreen" } do
+    properties["get_"..prop] = function(self)
+        return self.data[prop] or false
+    end
+
+    properties["set_"..prop] = function(self, value)
+        self.data[prop] = value or false
+
+        if value then
+            self:emit_signal("request::geometry", prop, nil)
+        end
+
+        self:emit_signal("property::"..prop, value)
+    end
+end
+
+function properties.get_screen(self)
+    return self.data.screen or screen[1]
+end
+
+function properties.set_screen(self, s)
+    s = screen[s]
+    self.data.screen = s
+
+    if self.x < s.geometry.x or self.x > s.geometry.x+s.geometry.width then
+        self:geometry { x = s.geometry.x }
+    end
+
+    if self.y < s.geometry.y or self.y > s.geometry.y+s.geometry.height then
+        self:geometry { y = s.geometry.y }
+    end
+
+    self:emit_signal("property::screen")
+end
+
 -- Create fake clients to move around
 function client.gen_fake(args)
     local ret = gears_obj()
@@ -34,6 +73,7 @@ function client.gen_fake(args)
     ret.border_width = 1
     ret.icon_sizes = {{16,16}}
     ret.name = "Example Client"
+    ret.data._struts = { top = 0, right = 0, left = 0, bottom = 0 }
 
     -- This is a hack because there's a `:is_transient_for(c2)` method
     -- and a `transient_for` property. It will cause a stack overflow
@@ -49,6 +89,7 @@ function client.gen_fake(args)
     -- Tests should always set a geometry, but just in case
     for _, v in ipairs{"x","y","width","height"} do
         ret[v] = ret[v] or 1
+        assert((not args[v]) or ret[v] == args[v])
     end
 
     -- Emulate capi.client.geometry
@@ -89,6 +130,10 @@ function client.gen_fake(args)
         return nil
     end
 
+    function ret:set_xproperty(prop, value)
+        ret[prop] = value
+    end
+
     function ret:get_icon(_)
         return require("beautiful").awesome_icon
     end
@@ -101,6 +146,32 @@ function client.gen_fake(args)
         --TODO
     end
 
+    function ret:apply_size_hints(w, h)
+        return w or ret.width, h or ret.height
+    end
+
+    function ret:kill()
+        local old_tags = ret:tags() or {}
+
+        for k, c in ipairs(clients) do
+            if c == ret then
+                ret:emit_signal("unmanaged", c)
+                ret.valid = false
+                table.remove(clients, k)
+                break
+            end
+        end
+
+        ret._tags = {}
+
+        for _, t in ipairs(old_tags) do
+            ret:emit_signal("untagged", t)
+            t:emit_signal("property::tags")
+        end
+
+        assert(not ret.valid)
+    end
+
     titlebar_meta(ret)
 
     function ret:tags(new) --FIXME
@@ -121,14 +192,55 @@ function client.gen_fake(args)
         return {}
     end
 
+    function ret:struts(new)
+        for k, v in pairs(new or {}) do
+            ret.data._struts[k] = v
+        end
+
+        return ret.data._struts
+    end
+
+    function ret:struts(new)
+        for k, v in pairs(new or {}) do
+            ret.data._struts[k] = v
+        end
+
+        return ret.data._struts
+    end
+
+    -- Set a dummy one for now since set_screen will corrupt it.
+    ret._old_geo = {}
+
+    -- Set the screen attributes.
+    local s = args.screen
+
+    -- Pick the screen from the geometry.
+    if not s then
+        for s2 in screen do
+            local geo = s2.geometry
+            if geo.x >= ret.x and geo.y >= ret.y and ret.x < geo.x+geo.width
+              and ret.y < geo.y+geo.height then
+                s = s2
+            end
+        end
+    end
+
+    -- This will happen if the screen coords are not {0,0} and the client had
+    -- an unspecified position.
+    s = s or screen[1]
+
+    properties.set_screen(ret, s)
+
+    -- Set the geometry *again* because the screen possibly overwrote it.
+    for _, v in ipairs{"x","y","width","height"} do
+        ret[v] = args[v] or ret[v]
+    end
+
     -- Record the geometry
     ret._old_geo = {}
     push_geometry(ret)
     ret._old_geo[1]._hide = args.hide_first
 
-    -- Set the attributes
-    ret.screen = args.screen or screen[1]
-
     -- Good enough for the geometry and border
     ret.drawin = ret
     ret.drawable = ret
@@ -138,10 +250,6 @@ function client.gen_fake(args)
     ret.below = false
     ret.above = false
     ret.sticky = false
-    ret.maximized = false
-    ret.fullscreen = false
-    ret.maximized_vertical = false
-    ret.maximized_horizontal = false
 
     -- Add to the client list
     table.insert(clients, ret)
@@ -149,8 +257,21 @@ function client.gen_fake(args)
     client.focus = ret
 
     setmetatable(ret, {
-        __index     = function(...) return meta.__index(...) end,
-        __newindex = function(...) return meta.__newindex(...) end
+        __index     = function(self, key)
+            if properties["get_"..key] then
+                return properties["get_"..key](self)
+            end
+
+            return meta.__index(self, key)
+        end,
+        __newindex = function(self, key, value)
+
+            if properties["set_"..key] then
+                return properties["set_"..key](self, value)
+            end
+
+            return meta.__newindex(self, key, value)
+        end
     })
 
     client.emit_signal("manage", ret)
diff --git a/tests/examples/shims/drawin.lua b/tests/examples/shims/drawin.lua
index 1f1e8436..2147b623 100644
--- a/tests/examples/shims/drawin.lua
+++ b/tests/examples/shims/drawin.lua
@@ -35,11 +35,20 @@ local function new_drawin(_, args)
     ret.data.drawable.surface  = cairo.ImageSurface(cairo.Format.ARGB32, 0, 0)
     ret.data.drawable.geometry = ret.geometry
     ret.data.drawable.refresh  = function() end
+    ret.data._struts           = { top = 0, right = 0, left = 0, bottom = 0 }
 
-    for _, k in pairs{ "buttons", "struts", "get_xproperty", "set_xproperty" } do
+    for _, k in pairs{ "buttons", "get_xproperty", "set_xproperty" } do
         ret[k] = function() end
     end
 
+    function ret:struts(new)
+        for k, v in pairs(new or {}) do
+            ret.data._struts[k] = v
+        end
+
+        return ret.data._struts
+    end
+
     local md = setmetatable(ret, {
                         __index     = function(...) return meta.__index(...) end,
                         __newindex = function(...) return meta.__newindex(...) end
diff --git a/tests/examples/shims/mouse.lua b/tests/examples/shims/mouse.lua
index 20c35f0d..128e49e6 100644
--- a/tests/examples/shims/mouse.lua
+++ b/tests/examples/shims/mouse.lua
@@ -53,20 +53,42 @@ function mouse.push_history()
     mouse.history = {}
 end
 
+local forced_screen = nil
+
 return setmetatable(mouse, {
     __index = function(self, key)
         if key == "screen" then
-            return screen[1]
+            if forced_screen and screen._deleted[forced_screen] then
+                forced_screen = nil
+            end
+
+            for s in screen do
+                if coords.x > s.geometry.x and coords.x < s.geometry.x +s.geometry.width
+                  and coords.y > s.geometry.y and coords.y < s.geometry.y +s.geometry.height then
+                    return s
+                end
+            end
+
+            -- Using capi.mouse.screen is *not* supported when there is zero
+            -- screen. Nearly all the code uses `mouse.screen` as its ultimate
+            -- fallback. Having no screens is tolerated during early
+            -- initialization and that's it.
+            return screen.count() > 0 and screen[1] or assert(
+                false, "Calling `mouse.screen` without screens isn't supported"
+            )
         end
         local h = rawget(mouse,"_i_handler")
         if h then
             return h(self, key)
         end
     end,
-    __newindex = function(...)
+    __newindex = function(_, k, v)
         local h = rawget(mouse,"_ni_handler")
-        if h then
-            h(...)
+        if k == "screen" then
+            -- This will assert if the screen is invalid
+            forced_screen = v and screen[v] or nil
+        elseif h then
+            h(_, k, v)
         end
     end,
 })
diff --git a/tests/examples/shims/root.lua b/tests/examples/shims/root.lua
index c85abe31..e79e9652 100644
--- a/tests/examples/shims/root.lua
+++ b/tests/examples/shims/root.lua
@@ -8,12 +8,22 @@ function root:tags()
     return root._tags
 end
 
-function root:size() --TODO use the screens
-    return 0, 0
+function root.size()
+    local geo = {x1 = math.huge, y1 = math.huge, x2 = 0, y2 = 0}
+
+    for s in screen do
+        geo.x1 = math.min( geo.x1, s.geometry.x                   )
+        geo.y1 = math.min( geo.y1, s.geometry.y                   )
+        geo.x2 = math.max( geo.x2, s.geometry.x+s.geometry.width  )
+        geo.y2 = math.max( geo.y2, s.geometry.y+s.geometry.height )
+    end
+
+    return math.max(0, geo.x2-geo.x1), math.max(0, geo.y2 - geo.y1)
 end
 
-function root:size_mm()
-    return 0, 0
+function root.size_mm()
+    local w, h = root.size()
+    return (w/96)*25.4, (h/96)*25.4
 end
 
 function root.cursor() end
diff --git a/tests/examples/shims/screen.lua b/tests/examples/shims/screen.lua
index bf7f119c..bc6c25d1 100644
--- a/tests/examples/shims/screen.lua
+++ b/tests/examples/shims/screen.lua
@@ -1,7 +1,31 @@
 local gears_obj = require("gears.object")
+local gears_tab = require("gears.table")
 
 local screen, meta = awesome._shim_fake_class()
-screen._count = 0
+screen._count, screen._deleted = 0, {}
+
+local function compute_workarea(s)
+    local struts = {top=0,bottom=0,left=0,right=0}
+
+    for _, c in ipairs(drawin.get()) do
+        for k,v in pairs(struts) do
+            struts[k] = v + (c:struts()[k] or 0)
+        end
+    end
+
+    for _, c in ipairs(client.get()) do
+        for k,v in pairs(struts) do
+            struts[k] = v + (c:struts()[k] or 0)
+        end
+    end
+
+    return {
+        x      = s.geometry.x      + struts.left,
+        y      = s.geometry.y      + struts.top ,
+        width  = s.geometry.width  - struts.left - struts.right ,
+        height = s.geometry.height - struts.top  - struts.bottom,
+    }
+end
 
 local function create_screen(args)
     local s = gears_obj()
@@ -19,7 +43,7 @@ local function create_screen(args)
     }
 
     function s._resize(args2)
-        local old  = s.geometry
+        local old  = gears_tab.clone(s.geometry)
         geo.x      = args2.x      or geo.x
         geo.y      = args2.y      or geo.y
         geo.width  = args2.width  or geo.width
@@ -27,39 +51,71 @@ local function create_screen(args)
         s:emit_signal("property::geometry", old)
     end
 
-    s.outputs = { ["LVDS1"] = {
-        mm_width  = 0,
-        mm_height = 0,
+    function s.fake_resize(self, x, y, width, height)
+        self._resize {
+            x=x,y=y,width=width,height=height
+        }
+    end
+
+    function s:fake_remove()
+        local i = s.index
+        table.remove(screen, i)
+        screen._deleted[s] = true
+        s:emit_signal("removed")
+        screen[screen[i]] = nil
+        s.valid = false
+    end
+
+    function s:swap(other_s)
+        local s1geo = gears_tab.clone(s.geometry)
+        local s2geo = gears_tab.clone(other_s.geometry)
+
+        s:fake_resize(
+            s2geo.x, s2geo.y, s2geo.width, s2geo.height
+        )
+        other_s:fake_resize(
+            s1geo.x, s1geo.y, s1geo.width, s1geo.height
+        )
+
+        s:emit_signal("swapped",other_s)
+        other_s:emit_signal("swapped",s)
+    end
+
+    s.outputs = { LVDS1 ={
+        name      = "LVDS1",
+        mm_width  = (geo.width /96)*25.4,
+        mm_height = (geo.height/96)*25.4,
     }}
 
     local wa = args.workarea_sides or 10
 
-    -- This will happen if `clear()` is called
-    if mouse and not mouse.screen then
-        mouse.screen = s
-    end
-
     return setmetatable(s,{ __index = function(_, key)
-        if key == "geometry" then
-            return {
-                x      = geo.x or 0,
-                y      = geo.y or 0,
-                width  = geo.width ,
-                height = geo.height,
-            }
-        elseif key == "workarea" then
-            return {
-                x      = (geo.x or 0) + wa  ,
-                y      = (geo.y or 0) + wa  ,
-                width  = geo.width    - 2*wa,
-                height = geo.height   - 2*wa,
-            }
-        else
-            return meta.__index(_, key)
-        end
-    end,
-    __newindex = function(...) return meta.__newindex(...) end
-})
+            assert(s.valid)
+
+            if key == "geometry" then
+                return {
+                    x      = geo.x or 0,
+                    y      = geo.y or 0,
+                    width  = geo.width ,
+                    height = geo.height,
+                }
+            elseif key == "workarea" then
+                if screen._track_workarea then
+                    return compute_workarea(s)
+                else
+                    return {
+                        x      = (geo.x or 0) + wa  ,
+                        y      = (geo.y or 0) + wa  ,
+                        width  = geo.width    - 2*wa,
+                        height = geo.height   - 2*wa,
+                    }
+                end
+            else
+                return meta.__index(_, key)
+            end
+        end,
+        __newindex = function(...) assert(s.valid); return meta.__newindex(...) end
+    })
 end
 
 local screens = {}
@@ -74,11 +130,13 @@ function screen._add_screen(args)
     screen[#screen+1] = s
     screen[s] = s
     screen._count = screen._count + 1
+
+    return s
 end
 
 function screen._get_extents()
     local xmax, ymax
-    for _, v in ipairs(screen) do
+    for v in screen do
         if not xmax or v.geometry.x+v.geometry.width > xmax.geometry.x+xmax.geometry.width then
             xmax = v
         end
@@ -90,8 +148,47 @@ function screen._get_extents()
     return xmax.geometry.x+xmax.geometry.width, ymax.geometry.y+ymax.geometry.height
 end
 
+-- The way the `screen` module is used to store both number and object is
+-- problematic since it can cause invalid screens to be "resurrected".
+local function catch_invalid(_, s)
+    -- The CAPI implementation allows `nil`
+    if s == nil then return end
+
+    -- Try to get the screens by output name.
+    if type(s) == "string" then
+        for s2 in screen do
+            for out in pairs(s2.outputs or {}) do
+                if out == s then
+                    return s2
+                end
+            end
+        end
+    end
+
+    assert(screen ~= s, "Some code tried (and failed) to shadow the global `screen`")
+
+    -- Valid numbers wont get this far.
+    assert(type(s) == "table", "Expected a table, but got a "..type(s))
+
+    if type(s) == "number" then return end
+
+    assert(s.geometry, "The object is not a screen")
+    assert(s.outputs, "The object is not a screen")
+
+    assert((not screen._deleted[s]) or (not s.valid), "The shims are broken")
+
+    assert(not screen._deleted[s], "The screen "..tostring(s).."has been deleted")
+
+    -- Other errors. If someone place an object in the `screen` module, it wont
+    -- get this far. So the remaining cases are probably bugs.
+    assert(false)
+end
+
 function screen._clear()
+    assert(#screen == screen._count)
     for i=1, #screen do
+        screen._deleted[screen[i]] = true
+        screen[i].valid = false
         screen[screen[i]] = nil
         screen[i] = nil
     end
@@ -126,11 +223,21 @@ local function iter_scr(_, _, s)
 
     local i = s.index
 
-    if i + 1 < #screen then
+    if i < #screen then
         return screen[i+1], i+1
     end
 end
 
+function screen._areas()
+    return {}
+end
+
+function screen.fake_add(x,y,width,height)
+    return screen._add_screen {
+        x=x,y=y,width=width,height=height
+    }
+end
+
 screen._add_screen {width=320, height=240}
 
 screen._grid_vertical_margin = 10
@@ -138,12 +245,15 @@ screen._grid_horizontal_margin = 10
 
 screen.primary = screen[1]
 
+screen._track_workarea = false
+
 function screen.count()
     return screen._count
 end
 
 return setmetatable(screen, {
-    __call = iter_scr
+    __call  = iter_scr,
+    __index = catch_invalid
 })
 
 -- vim: filetype=lua:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:textwidth=80
diff --git a/tests/examples/shims/tag.lua b/tests/examples/shims/tag.lua
index 60ef6b4a..5a4f3cf2 100644
--- a/tests/examples/shims/tag.lua
+++ b/tests/examples/shims/tag.lua
@@ -16,15 +16,19 @@ local function new_tag(_, args)
     awesome._forward_class(ret, tag)
 
     ret.data = {}
-    ret.name = args.name or "test"
+    ret.name = tostring(args.name) or "test"
     ret.activated = true
     ret.selected = not has_selected_tag(args.screen)
 
     function ret:clients(_) --TODO handle new
         local list = {}
         for _, c in ipairs(client.get()) do
-            if c.screen == (ret.screen or screen[1]) then
-                table.insert(list, c)
+            if #c:tags() > 0 then
+                for _, t in ipairs(c:tags()) do
+                    if t == ret then
+                        table.insert(list, c)
+                    end
+                end
             end
         end