TSUHelpers: add states:Replace() and states:Get() functions, + bug fixes

new functions:
states:Replace(key, newState) works like the Update function but set to nil fields missing in the new table
states:Get:(key, field?) returns a state table, or one of it's fields if the parameter "field" is set, returns nil if it doesn't exists

bug fixes:
recurseUpdate should copy content of new tables instead of it's address
don't copy the fields trigger & triggernum into allStates (this needs to be properly addressed)

Author: mrbuds

Diff for: WeakAuras/TSUHelpers.lua

@@ -43,30 +43,52 @@ local removeAll = function(states)
   return changed
 end
 
-local function recurseUpdate(t1, t2)
+local skipKeys = {
+  trigger = true,
+  triggernum = true
+}
+
+local function recurseReplaceOrUpdate(t1, t2, isRoot, replace)
   local changed = false
-  for k, v in pairs(t2) do
-    if type(v) == "table" and type(t1[k]) == "table" then
-      if recurseUpdate(t1[k], v) then
+  if replace then
+    -- Remove keys in t1 that are not in t2
+    for k in pairs(t1) do
+      if t2[k] == nil then
+        t1[k] = nil
         changed = true
       end
+    end
+  end
+  for k, v in pairs(t2) do
+    if isRoot and skipKeys[k] then
+      -- skip this key
     else
-      if t1[k] ~= v then
-        t1[k] = v
-        changed = true
+      if type(v) == "table" then
+        if type(t1[k]) ~= "table" then
+          t1[k] = {}
+          changed = true
+        end
+        if recurseReplaceOrUpdate(t1[k], v, false, replace) then
+          changed = true
+        end
+      else
+        if t1[k] ~= v then
+          t1[k] = v
+          changed = true
+        end
       end
     end
   end
   return changed
 end
 
 ---@type fun(states: states, key: key, newState: state): boolean
-local update = function(states, key, newState)
+local replaceOrUpdate = function(states, key, newState, replace)
   local changed = false
   local state = states[key]
   if state then
     fixMissingFields(newState)
-    changed = recurseUpdate(state, newState)
+    changed = recurseReplaceOrUpdate(state, newState, true, replace)
     if changed then
       state.changed = true
       states.__changed = true
@@ -88,7 +110,31 @@ end
 local createOrUpdate = function(states, key, newState)
   key = key or ""
   if states[key] then
-    return update(states, key, newState)
+    return replaceOrUpdate(states, key, newState, false)
+  else
+    return create(states, key, newState)
+  end
+end
+
+---@type fun(states: states, key: key, field: any?): any
+---return a state for a key, or a field of a state for a key/field
+local get = function(states, key, field)
+  key = key or ""
+  local state = states[key]
+  if state then
+    if field == nil then
+      return state
+    end
+    return state[field] or nil
+  end
+  return nil
+end
+
+---@type fun(states: states, key: key?, newState: state): boolean
+local createOrReplace = function(states, key, newState)
+  key = key or ""
+  if states[key] then
+    return replaceOrUpdate(states, key, newState, true)
   else
     return create(states, key, newState)
   end
@@ -97,7 +143,9 @@ end
 Private.allstatesMetatable = {
   __index = {
     Update = createOrUpdate,
+    Replace = createOrReplace,
     Remove = remove,
-    RemoveAll = removeAll
+    RemoveAll = removeAll,
+    Get = get
   }
 }