Diagnostics for unnecessary assert

Author: ribru17

changelog.md

@@ -2,6 +2,8 @@
 
 ## Unreleased
 <!-- Add all new changes here. They will be moved under a version at release -->
+`2025-3-13`
+* `NEW` `unnecessary-assert` diagnostic warns when asserting values that are always truthy
 
 ## 3.13.9
 `2025-3-13`

locale/en-us/script.lua

@@ -36,6 +36,8 @@ DIAG_OVER_MAX_ARGS      =
 'This function expects a maximum of {:d} argument(s) but instead it is receiving {:d}.'
 DIAG_MISS_ARGS          =
 'This function requires {:d} argument(s) but instead it is receiving {:d}.'
+DIAG_UNNECESSARY_ASSERT =
+'Unnecessary assert: this expression is always truthy.'
 DIAG_OVER_MAX_VALUES    =
 'Only has {} variables, but you set {} values.'
 DIAG_AMBIGUITY_1        =

locale/en-us/setting.lua

@@ -406,6 +406,8 @@ config.diagnostics['missing-return-value']  =
 'Enable diagnostics for return statements without values although the containing function declares returns.'
 config.diagnostics['need-check-nil']        =
 'Enable diagnostics for variable usages if `nil` or an optional (potentially `nil`) value was assigned to the variable before.'
+config.diagnostics['unnecessary-assert']    =
+'Enable diagnostics for redundant assertions on truthy values.'
 config.diagnostics['no-unknown']            =
 'Enable diagnostics for cases in which the type cannot be inferred.'
 config.diagnostics['not-yieldable']         =

locale/ja-jp/script.lua

@@ -36,6 +36,8 @@ DIAG_OVER_MAX_ARGS      =
 'この関数は最大で {:d} 個の引数を受け取りますが、{:d} 個の引数が渡されています。'
 DIAG_MISS_ARGS          =
 'この関数は少なくとも {:d} 個の引数を必要としますが、{:d} 個しか渡されていません。'
+DIAG_UNNECESSARY_ASSERT =
+'不要なアサーション: この式は常に真です。'
 DIAG_OVER_MAX_VALUES    =
 '変数は {} 個しかありませんが、{} 個の値が設定されています。'
 DIAG_AMBIGUITY_1        =

locale/ja-jp/setting.lua

@@ -406,6 +406,8 @@ config.diagnostics['missing-return-value']  = -- TODO: need translate!
 'Enable diagnostics for return statements without values although the containing function declares returns.'
 config.diagnostics['need-check-nil']        = -- TODO: need translate!
 'Enable diagnostics for variable usages if `nil` or an optional (potentially `nil`) value was assigned to the variable before.'
+config.diagnostics['unnecessary-assert']    = -- TODO: need translate!
+'Enable diagnostics for redundant assertions on truthy values.'
 config.diagnostics['no-unknown']            = -- TODO: need translate!
 'Enable diagnostics for cases in which the type cannot be inferred.'
 config.diagnostics['not-yieldable']         = -- TODO: need translate!

locale/pt-br/script.lua

@@ -36,6 +36,8 @@ DIAG_OVER_MAX_ARGS      =
 'A função aceita apenas os parâmetros {:d}, mas você passou {:d}.'
 DIAG_MISS_ARGS          =
 'A função recebe pelo menos {:d} argumentos, mas há {:d}.'
+DIAG_UNNECESSARY_ASSERT =
+'Asserção desnecessária: esta expressão é sempre verdadeira.'
 DIAG_OVER_MAX_VALUES    =
 'Apenas há {} variáveis, mas você declarou {} valores.'
 DIAG_AMBIGUITY_1        =

locale/pt-br/setting.lua

@@ -406,6 +406,8 @@ config.diagnostics['missing-return-value']  = -- TODO: need translate!
 'Enable diagnostics for return statements without values although the containing function declares returns.'
 config.diagnostics['need-check-nil']        = -- TODO: need translate!
 'Enable diagnostics for variable usages if `nil` or an optional (potentially `nil`) value was assigned to the variable before.'
+config.diagnostics['unnecessary-assert']    = -- TODO: need translate!
+'Enable diagnostics for redundant assertions on truthy values.'
 config.diagnostics['no-unknown']            = -- TODO: need translate!
 'Enable diagnostics for cases in which the type cannot be inferred.'
 config.diagnostics['not-yieldable']         = -- TODO: need translate!

locale/zh-cn/script.lua

@@ -36,6 +36,8 @@ DIAG_OVER_MAX_ARGS      =
 '函数最多接收 {:d} 个参数，但获得了 {:d} 个。'
 DIAG_MISS_ARGS          =
 '函数最少接收 {:d} 个参数，但获得了 {:d} 个。'
+DIAG_UNNECESSARY_ASSERT =
+'不必要的断言：此表达式始终为真值。'
 DIAG_OVER_MAX_VALUES    =
 '只有 {} 个变量，但你设置了 {} 个值。'
 DIAG_AMBIGUITY_1        =

locale/zh-cn/setting.lua

@@ -404,6 +404,8 @@ config.diagnostics['missing-return-value']  =
 '函数无值返回但函数使用`@return`标记了返回值'
 config.diagnostics['need-check-nil']        =
 '变量之前被赋值为`nil`或可选值(可能为 `nil`)'
+config.diagnostics['unnecessary-assert']    =
+'启用对冗余断言(针对始终为真值的表达式)的诊断'
 config.diagnostics['no-unknown']            =
 '变量的未知类型无法推断'
 config.diagnostics['not-yieldable']         =

locale/zh-tw/script.lua

@@ -36,6 +36,8 @@ DIAG_OVER_MAX_ARGS      =
 '函式最多接收 {:d} 個引數，但獲得了 {:d} 個。'
 DIAG_MISS_ARGS          =
 '函式最少接收 {:d} 個引數，但獲得了 {:d} 個。'
+DIAG_UNNECESSARY_ASSERT =
+'不必要的斷言：此表達式始終為真值。'
 DIAG_OVER_MAX_VALUES    =
 '只有 {} 個變數，但你設定了 {} 個值。'
 DIAG_AMBIGUITY_1        =