model: default field to editable if its compute function returns nil

2 files changed, 21 insertions, 14 deletions

diff --git a/acf2/model/field.lua b/acf2/model/field.lua
index 5a699f6..ebe35ab 100644
--- a/acf2/model/field.lua
+++ b/acf2/model/field.lua
@@ -56,13 +56,8 @@ M.Field = class(M.Member)
 
 function M.Field:init(params)
    if not params then params = {} end
-   params = setdefaults(
-      params,
-      {
-	 addr=params.compute and node.null_addr or nil,
-	 editable=(params.store or not params.compute) and true or false,
-	 visible=true
-      }
+   setdefaults(
+      params, {addr=params.compute and node.null_addr or nil, visible=true}
    )
 
    super(self, M.Field):init(params)
@@ -74,10 +69,6 @@ function M.Field:init(params)
       end
    end
 
-   if type(self.editable) ~= 'function' then
-      function self.editable(obj) return params.editable end
-   end
-
    self.condition = M.conv_filter(self.condition)
 
    if self.choice then
@@ -105,7 +96,19 @@ function M.Field:init(params)
    end
 end
 
-function M.Field:_editable(context) return self:editable(context.parent) end
+function M.Field:_editable(context)
+   if self.editable == nil then
+      if self.store or not self.compute then return true end
+      if self.compute then return self:_compute(context) == nil end
+      return false
+   end
+
+   if type(self.editable) == 'function' then
+      return self:editable(context.parent) and true or false
+   end
+
+   return self.editable
+end
 
 function M.Field:_choice(context) return self.choice end
 
@@ -135,12 +138,16 @@ end
 function M.Field:load(context)
    if not context.txn then return setmetatable({}, context) end
    local value
-   if self.compute then value = self:compute(context.parent, context.txn) end
+   if self.compute then value = self:_compute(context) end
    if value == nil then value = self:_load(context) end
    if value == nil then return self.default end
    return value
 end
 
+function M.Field:_compute(context)
+   return self:compute(context.parent, context.txn)
+end
+
 function M.Field:_load(context) return context.txn:get(context.addr) end
 
 function M.Field:_validate(context, value)
diff --git a/acf2/model/init.lua b/acf2/model/init.lua
index 31f4dd6..0e89bc6 100644
--- a/acf2/model/init.lua
+++ b/acf2/model/init.lua
@@ -189,7 +189,7 @@ function M.Collection:init(params, itype)
    self.itype = itype or node.Collection
    self.iparams = {
       destroy=self.destroy,
-      editable=self:editable(),
+      editable=self:_editable(),
       layout=self.layout,
       required=self.required,
       ui_member=self.ui_member