Diagnostics Configuration - GLua Language Server

Overview

The diagnostics section controls which checks run and how severe they appear. You can enable, disable, or re-level each diagnostic code.

Top-level options

Option	Type	Default	Description
`diagnostics.enable`	`boolean`	`true`	Enable diagnostics globally
`diagnostics.disable`	`string[]`	`[]`	Codes to disable entirely
`diagnostics.enables`	`string[]`	`[]`	Codes to explicitly enable (for codes that are Off by default)
`diagnostics.globals`	`string[]`	`[]`	Global variable names to whitelist (suppress `undefined-global`)
`diagnostics.globalsRegex`	`string[]`	`[]`	Regex patterns matching global names to whitelist
`diagnostics.severity`	`object`	`{}`	Map of code → severity level
`diagnostics.diagnosticInterval`	`integer`	`500`	Delay in milliseconds between a file change and diagnostics scan

Severity levels

Level	Appearance
`"error"`	Red error indicator, blocks type resolution display
`"warning"`	Yellow warning indicator
`"information"`	Blue information indicator
`"hint"`	Subtle underline hint

Full diagnostic reference

Codes marked Off start disabled. Add them to enables to turn them on.

Syntax & annotations

Code	Default	Severity	Description
`syntax-error`	On	Error	Lua syntax errors
`doc-syntax-error`	On	Error	Annotation syntax errors
`annotation-usage-error`	On	Error	Incorrect annotation usage (e.g. `@class` inside a function)
`unknown-doc-tag`	Off	Warning	Unrecognised annotation tag
`incomplete-signature-doc`	Off	Warning	Function missing `@param` or `@return` documentation
`missing-global-doc`	Off	Warning	Global function/class with no documentation

Type checking

Code	Default	Severity	Description
`type-not-found`	On	Warning	Referenced type not found in scope
`param-type-mismatch`	On	Warning	Argument type doesn’t match declared `@param` type
`missing-parameter`	On	Warning	Required parameter not passed
`redundant-parameter`	On	Information	Extra argument passed beyond declared parameters
`assign-type-mismatch`	On	Hint	Assignment value type doesn’t match declared type
`return-type-mismatch`	Off	Warning	Returned type doesn’t match declared `@return` type
`missing-return`	Off	Warning	Function with `@return` annotation missing a return statement
`missing-return-value`	On	Warning	`return` statement missing a required value
`redundant-return-value`	Off	Warning	`return` statement has extra value(s)
`cast-type-mismatch`	On	Warning	`@cast` target type is incompatible
`generic-constraint-mismatch`	On	Information	Generic type argument violates constraint
`enum-value-mismatch`	On	Warning	Value not part of the declared enum
`need-check-nil`	On	Hint	Potential nil dereference (try `if x then ... end`)
`unchecked-nil-access`	On	Warning	Chained access or call through an opaque table member that may be nil
`infer-unknown`	On	Hint	An otherwise unknown value was stabilized from usage context and may be incorrect
`infer-unguarded-child`	On	Warning	A child value was inferred from an unguarded parent relationship and may be incorrect

Nil diagnostics understand validity guards such as IsValid and annotated guard wrappers. See Guard metadata for custom wrappers.

Fields & access

Code	Default	Severity	Description
`undefined-field`	On	Warning	Field doesn’t exist on the type
`undefined-method`	On	Error	Method called with `:` doesn’t exist on the type or an inferred child type
`missing-fields`	On	Warning	Required fields not initialised in a table literal
`inject-field`	Off	Warning	Field assigned to a type outside its definition
`duplicate-doc-field`	On	Warning	Same field documented multiple times in a class
`undefined-doc-param`	On	Warning	`@param` names a parameter that doesn’t exist in the function signature
`access-invisible`	On	Warning	Accessing a `private` or `protected` member from outside its class
`read-only`	On	Warning	Writing to a read-only value

Variables & scoping

Code	Default	Severity	Description
`undefined-global`	On	Error	Global variable not defined or whitelisted
`undefined-global-assignment`	On	Warning	Undefined global used as a function argument or assigned to a variable / table field (alias: `undefined-global-argument`)
`unused`	On	Hint	Variable or function is declared but never used
`unused-self`	Off	Hint	`self` parameter is never used
`redefined-local`	On	Hint	Local variable redefined in the same scope
`redefined-label`	On	Warning	`::label::` defined multiple times
`local-const-reassign`	On	Error	Reassigning a `<const>`-attributed local

Control flow

Code	Default	Severity	Description
`unreachable-code`	On	Hint	Code after a `return`, `break`, or `error()` call
`unnecessary-assert`	Off	Warning	`assert` that can never fail
`unnecessary-if`	Off	Warning	`if` condition that is always true or false
`invert-if`	Off	Warning	`if` block that could be simplified by inverting the condition

Modules & requires

Code	Default	Severity	Description
`duplicate-require`	On	Hint	Module required more than once in the same file
`require-module-not-visible`	On	Warning	`require()` path target is not visible in the workspace

Documentation

Code	Default	Severity	Description
`deprecated`	On	Hint	Using a function, field, or class marked `@deprecated`
`discard-returns`	On	Warning	Return value of a `@nodiscard` function is discarded
`circle-doc-class`	On	Warning	Circular class inheritance detected

Code style

Code	Default	Severity	Description
`code-style-check`	Off	Warning	Code style violations
`duplicate-index`	On	Warning	Same table key used more than once
`duplicate-set-field`	Off	Warning	Same field set multiple times
`non-literal-expressions-in-assert`	Off	Warning	Non-literal values inside `assert()`
`unbalanced-assignments`	On	Warning	Different number of values and variables in a multi-assignment
`preferred-local-alias`	On	Hint	Suggest caching a global in a local variable
`await-in-sync`	On	Warning	Using `---@async` function result in a synchronous context

Type definitions

Code	Default	Severity	Description
`duplicate-type`	Off	Warning	Type defined more than once
`global-in-non-module`	Off	Warning	Global defined in a non-module file scope
`attribute-param-type-mismatch`	On	Warning	Attribute parameter type mismatch
`attribute-missing-parameter`	On	Warning	Required attribute parameter missing
`attribute-redundant-parameter`	On	Warning	Extra attribute parameter
`call-non-callable`	Off	Warning	Calling a value that is not callable

Garry’s Mod Lua

Code	Default	Severity	Description
`gmod-invalid-hook-name`	On	Warning	Invalid or unknown GMod hook name
`gmod-realm-mismatch`	On	Error	Client-only code used on the server, or server-only code used on the client
`gmod-realm-mismatch-heuristic`	On	Error	Likely realm mismatch when the file realm is not certain
`gmod-unknown-realm`	On	Hint	Realm could not be determined for a realm-sensitive call
`gmod-net-missing-network-counterpart`	On	Warning	`net.Start` block with no `net.Receive` in the opposite realm (or vice versa)
`gmod-net-read-write-order-mismatch`	On	Warning	`net.Read` order doesn’t match `net.Write` order
`gmod-net-read-write-type-mismatch`	On	Warning	`net.Read` type doesn’t match corresponding `net.Write` type
`gmod-net-read-write-bits-mismatch`	On	Warning	Literal bit-width differs between a matched write/read pair (e.g. `WriteUInt(8)` vs `ReadUInt(16)`)
`gmod-unknown-net-message`	On	Warning	Unregistered net message identifier
`gmod-duplicate-system-registration`	On	Hint	Duplicate registration for `net.Receive`, `concommand.Add`, `timer.Create`, etc.
`gmod-null-check`	On	Warning	Entity validity checked with truthiness or `nil` instead of `IsValid`

VS Code extension settings

You can also configure these settings in VS Code settings with the gluals.* prefix:

VS Code setting	.gluarc.json key	Type	Default	Description
`gluals.diagnostics.diagnosticInterval`	`diagnostics.diagnosticInterval`	`integer`	`500`	Scan delay in milliseconds
`gluals.strict.inferredTypeMismatch`	`strict.inferredTypeMismatch`	`boolean`	`false`	Stricter type checking for inferred values
`gluals.codeAction.insertSpace`	`codeAction.insertSpace`	`boolean`	`false`	Space after --- in diagnostic comments

Example configuration

.gluarc.json

{
  "diagnostics": {
    "enable": true,
    "diagnosticInterval": 500,
    "globals": ["GAMEMODE", "PLUGIN", "GM"],
    "globalsRegex": ["^PLUGIN_"],
    "enables": ["missing-return", "return-type-mismatch"],
    "disable": ["call-non-callable"],
    "severity": {
      "unused": "hint",
      "param-type-mismatch": "information",
      "need-check-nil": "hint",
      "undefined-field": "information"
    }
  }
}

​Overview

​Top-level options

​Severity levels

​Full diagnostic reference

​Syntax & annotations

​Type checking

​Fields & access

​Variables & scoping

​Control flow

​Modules & requires

​Documentation

​Code style

​Type definitions

​Garry’s Mod Lua

​VS Code extension settings

​Example configuration