new diagnostic: `missing-fields`

5 files changed, 223 insertions, 2 deletions

diff --git a/changelog.md b/changelog.md
index 0d4ec8a6..10aa311a 100644
--- a/changelog.md
+++ b/changelog.md
@@ -1,6 +1,7 @@
 # changelog
 
 ## 3.6.24
+* `NEW` diagnostic: `missing-fields`
 * `FIX` shake of `codeLens`
 * `FIX` [#2145]
 
diff --git a/script/core/diagnostics/missing-fields.lua b/script/core/diagnostics/missing-fields.lua
new file mode 100644
index 00000000..e23352bc
--- /dev/null
+++ b/script/core/diagnostics/missing-fields.lua
@@ -0,0 +1,72 @@
+local vm    = require 'vm'
+local files = require 'files'
+local guide = require 'parser.guide'
+local await = require 'await'
+
+---@async
+return function (uri, callback)
+    local state = files.getState(uri)
+    if not state then
+        return
+    end
+
+    ---@async
+    guide.eachSourceType(state.ast, 'table', function (src)
+        await.delay()
+
+        local defs = vm.getDefs(src)
+        local requiresKeys = {}
+        for _, def in ipairs(defs) do
+            if def.type == 'doc.class' then
+                if not def.fields then
+                    goto continue
+                end
+                if def.bindSource then
+                    if guide.isInRange(def.bindSource, src.start) then
+                        goto continue
+                    end
+                end
+                for _, field in ipairs(def.fields) do
+                    if  not field.optional
+                    and not vm.compileNode(field):isNullable() then
+                        local key = vm.getKeyName(field)
+                        if key and not requiresKeys[key] then
+                            requiresKeys[key] = true
+                            requiresKeys[#requiresKeys+1] = key
+                        end
+                    end
+                end
+            end
+            ::continue::
+        end
+
+        if #requiresKeys == 0 then
+            return
+        end
+
+        local myKeys = {}
+        for _, field in ipairs(src) do
+            local key = vm.getKeyName(field)
+            if key then
+                myKeys[key] = true
+            end
+        end
+
+        local missedKeys = {}
+        for _, key in ipairs(requiresKeys) do
+            if not myKeys[key] then
+                missedKeys[#missedKeys+1] = ('`%s`'):format(key)
+            end
+        end
+
+        if #missedKeys == 0 then
+            return
+        end
+
+        callback {
+            start   = src.start,
+            finish  = src.finish,
+            message = string.format('Missing fields: %s', table.concat(missedKeys, ', ')),
+        }
+    end)
+end
diff --git a/script/proto/diagnostic.lua b/script/proto/diagnostic.lua
index 8175a2c5..9c095531 100644
--- a/script/proto/diagnostic.lua
+++ b/script/proto/diagnostic.lua
@@ -62,6 +62,7 @@ m.register {
     'missing-return-value',
     'redundant-return-value',
     'missing-return',
+    'missing-fields',
 } {
     group    = 'unbalanced',
     severity = 'Warning',
diff --git a/test/diagnostics/common.lua b/test/diagnostics/common.lua
index a1dbe819..d061b4e4 100644
--- a/test/diagnostics/common.lua
+++ b/test/diagnostics/common.lua
@@ -156,13 +156,13 @@ print(A) -- no warning
 
 TEST [[
 ---@type iolib
-_ENV = {}
+_ENV = io
 <!print!>(stderr) -- `print` is warning but `stderr` is not
 ]]
 
 TEST [[
 ---@type iolib
-local _ENV = {}
+local _ENV = io
 <!print!>(stderr) -- `print` is warning but `stderr` is not
 ]]
 
@@ -2206,6 +2206,7 @@ end
 
 TEST [[
 ---@diagnostic disable: unused-local
+---@diagnostic disable: missing-fields
 ---@class A
 ---@field private x number
 local mt = {}
@@ -2220,6 +2221,7 @@ end
 
 TEST [[
 ---@diagnostic disable: unused-local
+---@diagnostic disable: missing-fields
 ---@class A
 ---@field private x number
 local mt = {}
@@ -2268,3 +2270,147 @@ local function foo(_ENV)
     Joe = "human"
 end
 ]]
+
+TEST [[
+---@diagnostic disable: unused-local
+---@class A
+---@field x number
+---@field y? number
+---@field z number
+
+---@type A
+local t = <!{}!>
+]]
+
+TEST [[
+---@diagnostic disable: unused-local
+---@class A
+---@field x number
+---@field y? number
+---@field z number
+
+---@type A
+local t = <!{
+    x = 1,
+}!>
+]]
+
+TEST [[
+---@diagnostic disable: unused-local
+---@class A
+---@field x number
+---@field y? number
+---@field z number
+
+---@type A
+local t = <!{
+    x = 1,
+    y = 2,
+}!>
+]]
+
+TEST [[
+---@diagnostic disable: unused-local
+---@class A
+---@field x number
+---@field y? number
+---@field z number
+
+---@type A
+local t = {
+    x = 1,
+    y = 2,
+    z = 3,
+}
+]]
+
+TEST [[
+---@diagnostic disable: unused-local
+---@class A
+---@field x number
+---@field y? number
+---@field z number
+
+---@type A
+local t = {
+    x = 1,
+    z = 3,
+}
+]]
+
+TEST [[
+---@diagnostic disable: unused-local
+---@class A
+---@field x number
+---@field y? number
+---@field z number
+
+---@param a A
+local function f(a) end
+
+f <!{}!>
+]]
+
+TEST [[
+---@diagnostic disable: unused-local
+---@class A
+---@field x number
+---@field y? number
+---@field z number
+
+---@param a A
+local function f(a) end
+
+f <!{
+    x = 1,
+}!>
+]]
+
+TEST [[
+---@diagnostic disable: unused-local
+---@class A
+---@field x number
+---@field y? number
+---@field z number
+
+---@param a A
+local function f(a) end
+
+f <!{
+    x = 1,
+    y = 2,
+}!>
+]]
+
+TEST [[
+---@diagnostic disable: unused-local
+---@class A
+---@field x number
+---@field y? number
+---@field z number
+
+---@param a A
+local function f(a) end
+
+f {
+    x = 1,
+    y = 2,
+    z = 3,
+}
+]]
+
+TEST [[
+---@diagnostic disable: unused-local
+---@class A
+---@field x number
+---@field y? number
+---@field z number
+
+---@param a A
+local function f(a) end
+
+f {
+    x = 1,
+    z = 3,
+}
+]]
diff --git a/test/diagnostics/type-check.lua b/test/diagnostics/type-check.lua
index dd9d1198..adfef561 100644
--- a/test/diagnostics/type-check.lua
+++ b/test/diagnostics/type-check.lua
@@ -174,6 +174,7 @@ m.ints = {}
 ]]
 
 TEST [[
+---@diagnostic disable: missing-fields
 ---@class A
 ---@field x A