cue-lang/cue v0.17.0-alpha.3

on GitHub

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

Evaluator

Several long-standing cycle-detection bugs have been fixed, such as self-referential uses of matchN and matchIf, self-feeding disjunctions, and comprehensions that read a let binding which refers back to the comprehension's own fields.

Fixed a bug where the same package imported via different qualified import paths (e.g. foo.com/bar@v0 or foo.com/bar:baz) did not share the same hidden field namespace.

Fix a data race which could occur when concurrently loading the same imported packages.

cmd/cue

Module replace directives

cue now supports replace directives, letting you substitute a module dependency with a local directory or a different remote module during development - for example while testing a fix to a dependency before it is published, or to replace a dependency with a fork including improvements.

This configuration lives in cue.mod/local-module.cue, which is excluded when publishing to registries. cue mod edit and cue mod tidy gain support for maintaining this file.

We have also published a how-to guide on replacing a dependency with a local module.

Read the full design and provide feedback in the proposal, or read the cue.mod/local-module.cue reference docs.

Other changes

Resolving an unversioned import from a dependency module now respects that module's own default major version, instead of always using the main module's default.

Fix a bug where the flag cue export --path was ignored when the inputs were pure CUE.

cue import --with-context now ensures that data represents the original raw input data, and not its interpretation like JSON Schema.
Command input parsing is improved so that CUE packages can come after data files, such as cue vet -c data.yaml ./schema.

A $CUE_CACHE_DIR directory is no longer required when loading CUE without external dependencies.

Standard library

Add time.ToUnix and time.ToUnixNano, which convert an RFC3339Nano time value into seconds or nanoseconds since the Unix epoch, complementing the existing Unix builtin.

Go API

⚠️ The modconfig.Registry interface is changed to report default major versions, which is required for resolving unversioned imports against each dependency module's own defaults. Clients that implement or wrap the interface will need to update. The new interface is future-proofed for upcoming modules changes.