inject_global_value

Parameters

This rule will find a global variable and replace it with a given value. The value can be defined in the rule configuration or taken from an environment variable.

To inject a static value, use the value property.

{
  rule: "inject_global_value",
  identifier: "GLOBAL",
  value: true,
}

If value is not specified, the env property can be defined to read an environment variable that will be read into a string.

{
  rule: "inject_global_value",
  identifier: "GLOBAL",
  env: "SOME_VARIABLE",
}

Alternatively, the env_json property allows you to read a JSON-encoded value (json5 is supported) from an environment variable. This is useful for injecting any data like booleans or structured data like arrays or objects.

{
  rule: "inject_global_value",
  identifier: "SETTINGS",
  env_json: "APP_SETTINGS",
}

When using the env or env_json property, the default_value property can be used to provide a fallback value when the environment variable is not defined. This prevents the rule from using nil as the default value.

{
  rule: "inject_global_value",
  identifier: "FEATURE_FLAG",
  env: "ENABLE_FEATURE",
  default_value: false,
}

This rule can be used in combination with the remove_unused_if_branch, compute_expression, and other rules, to eliminate dead branches. In addition to making your code smaller, it should make it faster (depending on how hot the code path is) since it is eliminating branch condition evaluations at client-side runtime.

Examples

if _G.AMOUNT > 10 or _G.CONSTANT ~= nil then
  --[[ ... ]]
end

if 11> 10 or 'Hello'~= nil then
  --[[ ... ]]
end

if _G.DEBUG then
  print('Debug information')
end

if true then
  print('Debug information')
end

if _G.AMOUNT > 10 or _G.CONSTANT ~= nil then
  --[[ ... ]]
end

if 11> 10 or 'Hello'~= nil then
  --[[ ... ]]
end

if _G.DEBUG then
  print('Debug information')
end

if true then
  print('Debug information')
end