---
title: July 2023
---

:::caution
This release contains **breaking changes**
:::

## New Features

### `@typespec/compiler` and core language

- New built-in linter system. Typespec libraries are able to define linting rules which can be configured in `tspconfig.yaml`. See documentation for [configuring a linter](https://typespec.io/docs/handbook/configuration#linter---configuring-linters) and [writing a linter](https://typespec.io/docs/extending-typespec/linters)
- Allow decorators, directives and doc comments to be specified in any order
- Format doc comments above decorators and directives
- Improve formatting for properties with comments and decorators
- Support for new Unicode 15.0 identifier characters

### Emitter framework

- Add `writeOutput` to TypeEmitter for additional customization in writing generated files
- Add `meta` property to source files and declarations to store arbitrary metadata
- Add support for emitting enum member references
- Add new `TypeEmitter` methods for scalar instantiation

### `@typespec/http` library

- Add documentation on automatic header name resolution from property name for `@header` decorator

### `@typespec/json-schema` emitter

- Support `@extension` for adding arbitrary vendor extensions into the output
- Add support for `Record<T>`
- Support templates instantiated with intrinsic types and type expressions
- Export emitter and related types from the npm package
- By default, types that are not marked with `@jsonSchema` or are within a namespace with `@jsonSchema` are bundled into the schemas that reference them. Set the `emitAllRefs` option to true to get the previous behavior of emitting all types referenced as JSON Schema

### `@typespec/openapi3` emitter

- Omit `x-typespec-name` extension by default from openapi3 output. A new configuration and command line option `include-x-typespec-name: \"inline-only\" | \"never\"` has been added to get previous behavior

### `@typespec/rest` library

- Add `isListOperation` function migrated from `@typespec/compiler`

## Bug Fixes

### `@typespec/compiler` and core language bug fixes

- Add support for `UTF-8 with bom` for other files loaded by TypeSpec compiler. `.tsp` files already had support, this make it more available for any library/emitter using the compiler api to load a file.
- Fix signature help after comment with no closing parenthesis or angle bracket
- Doc comment `/** */` should override base type doc in `model is` or `op is`
- Formatter incorrectly formatting `::` to `.`
- Fix formatting issue with comment between decorator and scalar or interface
- Fix stack overflow when a circular reference with `op is` exists inside an interface.
- Clean up handling of non-standard entrypoints in language server
- Fix stack overflow when referencing decorator target in checker and projections

### `@typespec/openapi3` emitter bug fixes

- OpenAPI emitters: treat union namespaces like namespaces for other types

### Emitter framework bug fixes

- Fix that some context methods were not being passed the expected parameters
- Fix that context was set incorrectly for some `TypeEmitter` methods, and add missing context methods for model properties, enum members, and union variants

### `@typespec/json-schema` emitter bug fixes

- Fix a bug that could result in a schema being bundled more than once

## Breaking Changes

### For Specification Authors

- Update tsp init template schema for future extensibility. Older tsp version will fail validation when trying to initialize a project with a new template definition.
- Json Schema Emitter: the namespace has been corrected to TypeSpec.JsonSchema. Update any using statements from `JsonSchema` to `TypeSpec.JsonSchema`, and any references from `JsonSchema.[Type]` to `TypeSpec.JsonSchema.[Type]`.

### For Emitters and Libraries

- Minimum version of TypeScript updated to 5.0. TypeSpec is using new features available in TypeScript 5.0 which result in a definition file not parsable by older version. Note that this only affect compiling TypeScript code and is not breaking any JS or TypeSpec code. [See more information on typescript 5.0](https://devblogs.microsoft.com/typescript/announcing-typescript-5-0/)
- Emitter Framework: Add support for templates instantiated with types without declared names. In such cases, `TypeEmitter`'s declarationName method may return `undefined`, and so the various `*Instantiation` methods might be called with an undefined name, and `AssetEmitter`'s `emitDeclarationName` method might return undefined.
- Make internal `@resourceTypeForKeyParam` decorator in `@typespec/rest` library private

## Deprecations

- `@list` decorator from TypeSpec core is deprecated. Use `@listsResource` from `@typespec/http` instead
- `isListOperation` function from TypeSpec core is deprecated. Use `isListOperation` from `@typespec/http` instead
- `getListOperationType` from TypeSpec core is deprecated
- `@typespec/linter` Package is deprecated in favor of built-in linter system
