cue-lang/cue v0.16.0-alpha.1

on GitHub

Changes which may break some users are marked below with: ⚠️

Language

As a reminder, we have two ongoing language experiments since v0.15; a replacement for struct embedding and a rework of aliases. Please give these a try and report any issues or feedback!

⚠️ The cmdreferencepkg global experiment is now stable, meaning that CUE_EXPERIMENT=cmdreferencepkg is always enabled.

#"""# is now accepted as a string literal quoting a double quote, ".

Multiline string literals now require a trailing newline, matching the language spec.

Evaluator

Performance

Further improve the use of caching in the typochecker algorithm; this provides speed-ups of up to 80% on some large projects.

Very large structs (tested with 20,000 fields) are up to 80% faster now, as we were repeating some work unnecessarily.

A great deal of effort has gone into reducing the allocations and memory usage across a number of projects. For some of these, memory usage is down by as much as 60%.

These improvements were possible thanks to our Unity service, letting us analyze CUE's performance and test for regressions on third party projects. Contact @mvdan on Discord, Slack, or via the Unity page to ensure that your project is included or you are running into slowness.

Other changes

Fix a regression introduced in v0.13 where the or built-in with literal arguments could stop behaving like a disjunction.

A number of panics and other bugs in the evaluator which were reported since v0.15.0 have been fixed; thank you to all who reported these.

cmd/cue

Add support for $DOCKER_AUTH_CONFIG to directly provide the contents of $DOCKER_CONFIG/config.json to authenticate with module registries, matching Docker's current behavior.

The --outfile flag now works when given non-regular files such as named pipes or sockets.

⚠️ cue mod publish no longer ignores sub-directories containing a go.mod file as if they were nested CUE modules; those are already skipped based on the presence of cue.mod.

⚠️ Using cue inside the cue.mod directory now fails consistently with a clear error message to not place CUE code there. Previously, some commands worked while others failed with confusing errors.

LSP server

Completions: a complete overhaul of how the LSP server suggests code completions. This solves the previous naïve implementation which would only make suggestions after a field name or path had been started. Now completions are available from within whitespace.

Embedded paths with mutual dependencies: embedded paths with multiple components (e.g. a.b.c) can in some cases only be fully resolved after the resolution of other embedded paths. The LSP server can now correctly handle these dependencies.

Document Symbols: the CUE LSP server now implements LSP "Document Symbols" functionality. This is often used by editors to provide light-weight breadcrumb navigation within a file.

Diagnostics: some preliminary diagnostics are now sent from the LSP server back to the editor. Initially this mainly indicates syntax errors in CUE files, but this can be extended in the future.

Bug fixes: many smaller bug fixes, addressing issues around imports, path resolution, formatting of standalone CUE files, amongst others.

See our Getting Started wiki page for instructions on how to set it up with your editor.

Please report any bugs or missing features you encounter via the Issue tracker or via the #lsp channels on Discord or Slack.

Encodings

cue get go now detects which Go packages use Kubernetes type semantics via // +k8s:openapi-gen=true and obeys the field annotations // +optional and // +nullable.

cue get go gains a --codec flag to configure the use and priority of Go struct field tags like json or yaml.

Fix a bug where cue get go could skip over fields whose type implements one of the supported marshaling interfaces.

Fix a few bugs where cue get go could result in invalid or failing CUE code.

JSON Schema's Config.OpenOnlyWhenExplicit option is now exposed for the CLI via the filetype tag jsonschema+openOnlyWhenExplicit.

JSON Schema now properly encodes hash references for better compatibility with other tools.

Standard library

The strconv package adds ParseNumber, like ParseInt or ParseFloat but allowing other CUE number strings such as 1Ki.

The net package adds InCIDR to test whether an IP is contained by a CIDR string.

The net package adds ParseCIDR to extract useful information from a CIDR string.

Go API

cue.Value.Decode now supports the new cue.Unmarshaler interface, allowing Go types to implement their own CUE value decoding logic via an UnmarshalCUE(cue.Value) error method.

The new cue.IsIncomplete function reports whether the given value is a CUE incomplete error.

⚠️ cue.Value.Decode now uses cue.IsIncomplete to not treat incomplete errors as fatal, allowing the decoding to continue.

Fix a bug where cue.Value.Decode could behave incorrectly when decoding a CUE null or incomplete value.

⚠️ The long-deprecated cue/ast.Node.Comments and cue/ast.Node.AddComment interface methods are now removed; use cue/ast.Comments and cue/ast.AddComment respectively.

⚠️ The long-deprecated and unused cue/parser.FromVersion and cue/parser.DeprecationError APIs are now removed.