A set of Detekt rules to help prevent common errors in projects using Jetpack Compose.

Here are some highlights of rules in this rule set:

• ReusedModifierInstance finds usages of modifier parameter on non-top-level children of a composable function. This tends to happen during refactorings and often leads to incorrect rendering of a composable

• UnnecessaryEventHandlerParameter suggests hoisting event argument passing to the upper level which often simplifies individual composable components

• ModifierHeightWithText suggests using Modifier.heightIn() instead of Modifier.height() on a layouts which have Text children, so that if the text turns out to be long and would wrap, layout will not cut it off

• ComposableEventParameterNaming ensures that all event handler parameters of composable functions are named in the same Compose-like style, i.e. they have on prefix and do not use past tense

• ComposableParametersOrdering suggests separating required an optional parameters of the composable function into groups

• ModifierParameterPosition ensures that modifier is declared as a first parameter

• ModifierDefaultValue ensures that modifier parameter has a correct default value

• MissingModifierDefaultValue checks if modifier default value is specified

• PublicComposablePreview finds and reports composable previews which are not marked as private

• TopLevelComposableFunctions ensures that all composable functions are top-level functions (disabled by default)

• ComposeFunctionName ensures that Composable functions which return Unit should start with upper-case while the ones that return a value should start with lower case

• and others...

Rules can be individually turned on or off in the configuration file.
More detailed rule descriptions with code snippets can be found in the Wiki.

Add detekt rules plugin in your build.gradle (or use any other supported method):

dependencies {
  detektPlugins("ru.kode:detekt-rules-compose:1.2.2")
}

and then add this configuration section to your detekt-config.yml to activate the rules:

compose:
  ReusedModifierInstance:
    active: true
  UnnecessaryEventHandlerParameter:
    active: true
  ComposableEventParameterNaming:
    active: true
  ComposableParametersOrdering:
    active: true
  ModifierHeightWithText:
    active: true
  ModifierParameterPosition:
    active: true
  ModifierDefaultValue:
    active: true
  MissingModifierDefaultValue:
    active: true
  PublicComposablePreview:
    active: true
  TopLevelComposableFunctions:
    active: true
  ComposeFunctionName:
    active: true

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