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Change Log

Version 1.7.2


  • New: Detect expression bodies with return· and throw· prefixes.
  • Fix: Omit visibility modifiers on custom accessors.

Version 1.7.1


  • Fix: 1.7.0 was published using JDK 11 which set "org.gradle.jvm.version" to "11" in Gradle metadata, making it impossible to use the library on earlier Java versions (see #999). 1.7.1 is published with JDK 8, which fixes the problem.

Version 1.7.0


  • New: Kotlin 1.4.10.
  • New: Generated code is now compatible with the explicit API mode by default.
  • New: Escape soft and modifier keywords, in addition to hard keywords.
  • New: Improve enum constants generation for cleaner diffs.
  • New: Disallow setters on immutable properties.
  • New: Ensure trailing new lines in expression bodies.
  • New: Ensure trailing new lines after parameterless custom setters.
  • Fix: Don’t auto-convert properties with custom accessors to primary constructor properties.
  • Fix: Don’t allow parameterless setters with body.
  • Fix: Prevent auto-wrapping spaces inside escaped keywords.

Version 1.6.0


  • New: Deprecate Mirror API integrations.

Mirror API integrations, such as TypeElement.asClassName() and FunSpec.overriding(ExecutableElement), are being deprecated in this release. These KotlinPoet APIs are most often used in annotation processors. Since kapt runs annotation processors over stubs, which are Java files, a lot of the Kotlin-specific information gets lost in translation and cannot be accessed by KotlinPoet through the Mirror API integrations. Examples include:

  • Alias types, such as kotlin.String, get converted to their JVM representations, such as java.lang.String.
  • Type nullability information is not accessible.
  • suspend functions are seen as simple functions with an additional Continuation parameter.

The correct solution is to switch to KotlinPoet-metadata or KotlinPoet-metadata-specs API, which fetches Kotlin-specific information from the @Metadata annotation and produces correct KotlinPoet Specs. We may explore adding new metadata-based alternatives to the deprecated APIs in the future.

  • New: Kotlin 1.3.72.
  • New: Improve MemberName to support operator overloading.
  • New: Support generics in AnnotationSpec.
  • New: Add support for functional interfaces.
  • New: Make more FunSpec.Builder members public for easier mutation.
  • Fix: Properly propagate implicit type and function modifiers in nested declarations.
  • Fix: Properly escape type names containing $ character.
  • Fix: Don’t emit LambdaTypeName annotations twice.
  • Fix: Preserve tags in TypeName.copy().

Version 1.5.0


KotlinPoet now targets JDK8, which means that executing a build that includes KotlinPoet as a dependency on a machine with an older version of JDK installed won’t work. This has no effect on the code that KotlinPoet produces: the code can still be compiled against JDK6, as long as it doesn’t use any features that were introduced in newer releases.

  • New: Kotlin 1.3.61.
  • New: Add support for processing FileFacades in KotlinPoet-metadata.
  • New: Add support for inner nested and companion objects on annotation classes.
  • New: Improve error messages for mismatched open/close statement characters.
  • New: Tag AnnotationSpecs with the annotation mirror when available.
  • New: Include annotations on enum entries when creating TypeSpecs from metadata.
  • Fix: Fix metadata parsing for types.
  • Fix: Allow file names that are Kotlin keywords.
  • Fix: Properly escape type alias names with backticks.
  • Fix: Allow creating TypeSpecs with names that can be escaped with backticks.
  • Fix: Properly escape enum constant names with backticks.
  • Fix: Maintain proper ordering of properties and initializers when emitting a TypeSpec. Note: with this change, any properties declared after any initializer blocks will not be added to the primary constructor and will instead be emitted inside the TypeSpec body.
  • Fix: Don’t emit a leading new line if type KDoc is empty but parameter KDocs are present.
  • Fix: Ensure KotlinPoet-metadata resolves package names properly.

## Version 1.4.4


  • Fix: Support reified inline types in KotlinPoet-metadata.

Version 1.4.3


  • Fix: Don’t emit stubs for abstract functions in KotlinPoet-metadata.

Version 1.4.2


  • Fix: Properly handle abstract elements in KotlinPoet-metadata.
  • Fix: Properly handle typealiases in KotlinPoet-metadata.
  • Fix: Properly render % symbols at the end of KDocs.

Version 1.4.1


  • New: Add annotations support to TypeAliasSpec.
  • New: Read type annotations from Kotlin Metadata.
  • New: Introduce ImmutableKmDeclarationContainer.
  • Fix: Use full package name for shading auto-common.
  • Fix: Support reading self-type variables (e.g. Asset<A : Asset<A>>) from Kotlin Metadata.

Version 1.4.0


  • New: This release introduces the new KotlinPoet-metadata API that makes it easy to introspect Kotlin types and build KotlinPoet Specs based on that data.

The strategy for type introspection is driven by ClassInspector, which is a basic interface for looking up JVM information about a given Class. This optionally is used by the toTypeSpec()/toFileSpec() APIs in kotlinpoet-metadata-specs artifact to inform about Classes with information that isn’t present in metadata (overrides, JVM modifiers, etc). There are two batteries-included implementations available in ReflectiveClassInspector (for reflection) and ElementsClassInspector (for the javax Elements API in annotation processing). These implementations are available through their respective kotlinpoet-classinspector-* artifacts. For more information refer to the KotlinPoet-metadata-specs README.

At the time of this release the API is in experimental mode and has to be opted into via the KotlinPoetMetadataPreview annotation.

  • New: Kotlin 1.3.50.
  • New: A new constructor to simplify creation of ParameterSpec instances.
  • New: New ClassName constructors.
  • New: TypeName and subclasses can now store tags.
  • New: Optional parameters added to toBuilder() methods of most Specs.
  • New: List overrides for Spec methods that accept varargs.
  • New: CodeBlock.Builder.clear() helper method.
  • New: FunSpec.Builder.clearBody() helper method.
  • Fix: Properly escape enum constant names.
  • Fix: Ensure trailing newlines in KDoc and function bodies.
  • Fix: TypeVariableNames with empty bounds will now default to Any?.
  • Fix: Don’t emit parens for primary constructors.
  • Fix: ClassNames with empty simple names are not allowed anymore.
  • Fix: Throw if names contain illegal characters that can’t be escaped with backticks.

Version 1.3.0


  • New: Don’t inline annotations in the primary constructor.
  • New: Force new lines when emitting primary constructors.
  • New: Support using MemberNames as arguments to %N.
  • New: Add more ClassName constants: ClassName.STRING, ClassName.LIST, etc.
  • New: Add ClassName.constructorReference() and MemberName.reference().
  • New: Make %N accept MemberNames.
  • New: Escape spaces in import aliases.
  • New: Escape spaces in ClassNames.
  • New: Escape spaces in MemberNames.
  • New: Escape imports containing spaces.
  • New: Escape package name containing spaces.
  • New: Use 2-space indents.
  • New: Only indent one level on annotation values.
  • Fix: Pass only unique originating elements to Filer.
  • Fix: Fix bug with MemberNames in same package nested inside a class.

Version 1.2.0


  • New: Add writeTo(Filer) and originating element API.
  • New: Make *Spec types taggable.
  • New: Make FunSpec.Builder#addCode take vararg Any?.
  • Fix: Import members from default package.
  • Fix: Add non-wrapping spaces in control flow creation methods.
  • Fix: Named “value” argument being omitted in annotation array types.

Version 1.1.0


  • New: Kotlin 1.3.21.
  • New: Support referencing members using %M and MemberName type.
  • New: Add extensions for getting a MemberName from a ClassName, KClass and Class.
  • New: Allow passing CodeBlocks as arguments to %P.
  • New: Allow interface delegation for objects.
  • Fix: Don’t emit visible whitespace in toString().
  • Fix: Prevent line wrapping in weird places inside function signature.
  • Fix: No line wrapping between val and property name.
  • Fix: Allow passing line prefix into LineWrapper to enable proper line wrapping in KDoc.
  • Fix: Add newline for TypeSpec Kdoc with no tags.
  • Fix: Add newline for remaining Specs.
  • Fix: Fix kdoc formatting for property getter/setters.
  • Fix: Don’t wrap single line comments inside FunSpec.
  • Fix: Add non-wrapping package name.
  • Fix: Remove n^2 algorithm in CodeWriter.resolve() by precomputing all of the nested simple names of a TypeSpec.
  • Fix: Fix edge case with empty enum classes.
  • Fix: Fix Nullable Type Parameter handling in KType.asTypeName().
  • Fix: Fix incorrect long comment wrapping in FileSpec.
  • Fix: Attach primary constructor param/property KDoc to the element vs emitting it inside the type header.

Version 1.0.1


  • New: Allow enums without constants.
  • New: Improved formatting of TypeSpec KDoc.
  • New: Support @property and @param KDoc tags in TypeSpec.
  • Fix: Use pre-formatted strings for arguments to %P.

Version 1.0.0


  • New: Kotlin 1.3.11.
  • Fix: Prevent wrapping in import statements.

Version 1.0.0-RC3


  • New: Kotlin 1.3.10.
  • New: Add %P placeholder for string templates.
  • New: Add support for receiver kdoc.
  • New: Avoid emitting Unit as return type.
  • New: Add support for empty setters.
  • New: Add checks for inline classes.
  • New: Escape property and variable names if keywords.
  • New: Replace %>, %<, %[, %] placeholders with , , «, ».
  • New: Replace %W with space, and add · as a non-breaking space.
  • New: Change TypeName to sealed class.
  • New: Documentation improvements.
  • New: Replace TypeName modifier methods with copy().
  • New: Rename members of WildcardTypeName to match with the producer/consumer generics model.
  • New: Rename TypeName.nullable into TypeName.isNullable.
  • New: Rename LambdaTypeName.suspending into LambdaTypeName.isSuspending.
  • New: Rename TypeVariableName.reified into TypeVariableName.isReified.
  • Fix: Emit star-projection only for types with Any? upper bound.
  • Fix: Fold property with escaped name.

Version 1.0.0-RC2


  • New: Kotlin 1.2.71.
  • New: README improvements.
  • New: Allow opening braces and params in beginControlFlow().
  • New: Add KDoc to ParameterSpec, collapse into parent KDoc.
  • New: Support TypeVariables in PropertySpec.
  • New: Add parens for annotated types in LambdaTypeName.
  • New: Improve error messaging and documentation for inline properties.
  • New: Allow sealed classes to declare abstract properties.
  • New: Added buildCodeBlock() helper function.
  • New: Allow using CodeBlocks with statements as property initializers and default parameter values.
  • New: Rename NameAllocator.clone() into `NameAllocator.copy().
  • New: Rename TypeName.asNonNullable() to TypeName.asNonNull().
  • New: Remove PropertySpec.varBuilder() (use mutable() instead).
  • New: Allow importing top-level members in default package.
  • New: Add overloads to add KDoc to return type.
  • Fix: Distinguishing IntArray and Array<Int> when creating TypeName.
  • Fix: Use TypeName instead of ClassName as parameter type of plusParameter().
  • Fix: Keep type-parameter variance when constructing TypeName from KType.
  • Fix: Don’t validate modifiers when merging properties with primary constructor parameters.
  • Fix: Escape $ characters in formatted strings.
  • Fix: FileSpec.Builder blank package and subfolder fix.
  • Fix: Append new line at end of parameter KDoc.
  • Fix: Add parameter KDoc in toBuilder().

Version 1.0.0-RC1


  • New: Escape keywords in imports and canonical class names.
  • New: Improve external support.
  • New: Extensions for KType and KTypeParameter.
  • New: Add builder methods to simplify adding common kotlin.jvm annotations.
  • New: Enums are able to have companion objects.
  • New: Add missing primaryConstructor & companionObject to TypeSpec#toBuilder().
  • New: Make subtype checking vals inside Kind public.
  • New: Escape (class/property/function/variable) names automatically if they contain space, hyphen, or other symbols.
  • New: Improve ParameterizedTypeName API.
  • New: Add WildcardTypeName.STAR constant.
  • New: Expose mutable builder properties and move their validations to build-time.
  • Fix: Use regular indents for parameter lists.
  • Fix: Inline annotations on properties defined in primary constructor.
  • Fix: Use Any? as the default type variable bounds.
  • Fix: Fix importing annotated TypeName.
  • Fix: If any primary constructor property has KDoc, put properties on new lines.
  • Fix: Properly emit where block in type signature.
  • Fix: Avoid type name collisions in primary constructor.
  • Fix: Remove implicit TypeVariable bound when more bounds are added.
  • Fix: Combine annotations and modifiers from constructor params and properties.
  • Fix: Replace delegate constructor args along with the constructor.

Version 0.7.0


  • New: Increase indent to 4 spaces.
  • New: Delegate super interfaces as constructor parameters.
  • New: Support PropertySpecs as CodeBlock literals.
  • New: Support KDoc for TypeAliasSpec.
  • New: Allow for adding an initializer block inside a companion object.
  • New: Escape name in ParameterSpec which is also a keyword.
  • New: Escape names in statements.
  • New: Set com.squareup.kotlinpoet as automatic module name.
  • New: Support suspending lambda types.
  • New: Support named LambdaTypeName parameters.
  • New: Support dynamic type.
  • New: Disallow wildcard imports.
  • New: Depend on Kotlin 1.2.21.
  • Fix: Correct handling of super-classes/interfaces on anonymous classes.
  • Fix: Fix boundary filtering to Any?.
  • Fix: Wrap long property initializers.
  • Fix: Fix formatting and indentation of parameter lists.

Version 0.6.0


  • New: Support lambda extensions.
  • New: Support renames in imports like import bar.Bar as bBar.
  • New: Support extension and inline properties.
  • New: Support reified types.
  • New: Expose enclosed types inside LambdaTypeName.
  • New: Depend on Kotlin Kotlin 1.1.51.
  • New: Improved API and formatting of annotations.
  • New: Improved multiplatform support.
  • Fix: Escape function and package names if they are a Kotlin keyword.
  • Fix: Properly format WildcardTypeName’s class declaration.

Version 0.5.0


  • New: Rename addFun() to addFunction().
  • New: Rename KotlinFile to FileSpec.
  • New: Rename KotlinFile.addFileAnnotation() to addAnnotation().
  • New: Rename KotlinFile.addFileComment() to addComment().
  • New: Support cross-platform code, including HEADER and IMPL modifiers.
  • New: Support type variables for type aliases.
  • New: Support constructor delegation.
  • New: Support named companion objects.
  • New: Depend on Kotlin 1.1.4-3.
  • Fix: Format one parameter per line when there are more than two parameters.
  • Fix: Don’t emit braces when the constructor body is empty.
  • Fix: Do not invoke superclass constructor when no primary constructor.
  • Fix: Enforce the right modifiers on functions.

Version 0.4.0


  • New: Change KotlinPoet’s extensions like asClassName() to be top-level functions.
  • New: Add declaration-site variance support.
  • New: Improve handling of single expression bodies.
  • New: Support file annotations.
  • New: Support imports from the top-level file.
  • New: Accept superclass constructor parameters.
  • New: Support primary constructors using the constructor keyword.
  • Fix: Don’t emit setter parameter types.
  • Fix: Support Kotlin keywords in NameAllocator.
  • Fix: Emit the right default parameters for primary constructors.
  • Fix: Format annotations properly when used as parameters.
  • Fix: Recognize imports when emitting nullable types.
  • Fix: Call through to the superclass constructor when superclass has a no-args constructor.
  • Fix: Omit class braces if all properties are declared in primary constructor.
  • Fix: Don’t emit empty class bodies.
  • Fix: Emit the right syntax for declaring multiple generic type constraints.
  • Fix: Support properties on objects, companions and interfaces.
  • Fix: Use AnnotationSpec for throws.

Version 0.3.0


  • New: Objects and companion objects.
  • New: TypeAliasSpec to create type aliases.
  • New: LambdaTypeName to create lambda types.
  • New: Collapse property declarations into constructor params.
  • New: Extension and invoke functions for creating type names: Runnable::class.asClassName().
  • New: Basic support for expression bodies.
  • New: Basic support for custom accessors.
  • New: Remove Filer writing and originating elements concept. These stem from javac annotation processors.
  • Fix: Generate valid annotation classes.
  • Fix: Use KModifier for varargs.
  • Fix: Use ParameterizedTypeName for array types.
  • Fix: Extract Kotlin name from KClass instead of Java name.
  • Fix: Emit valid class literals: Double::class instead of Double.class.
  • Fix: Emit modifiers in the expected order.
  • Fix: Emit the correct syntax for enum classes and overridden members.

Version 0.2.0


  • New: Flip API signatures to be (name, type) instead of (type, name).
  • New: Support for nullable types.
  • New: Support delegated properties.
  • New: Extension functions.
  • New: Support top-level properties.
  • Fix: Inheritance should use : instead of extends and implements.
  • Fix: Make initializerBlock emit init {}.

Version 0.1.0


  • Initial public release.