Adjust the implements clause of IntX

[eernstg]

Adjust the implements clause of IntX.

See dart-lang/sdk#59776 for breaking change processing.

Currently, IntX implements Comparable<Object>. This causes the equation X extends Comparable<X> to have no solution which is a supertype of IntX (and, hence, Int64 and Int32). This is inconvenient because it causes invocations of methods like the extension method sortedBy to fail: There is no actual type argument that satisfies the constraints.

With this PR, IntX is a subtype of Comparable<IntX>, which means that said methods can now be invoked. Type inference fails when the language version is below 3.7.0 (so the type argument IntX must be provided explicitly), but from 3.7.0 and up the feature 'inference-using-bounds' is enabled by default, and type inference will then succeed.

[github-actions]

Package publishing

Package	Version	Status	Publish tag (post-merge)
package:args	2.6.1-wip	WIP (no publish necessary)
package:async	2.13.0	already published at pub.dev
package:characters	1.4.0	already published at pub.dev
package:collection	1.20.0-wip	WIP (no publish necessary)
package:convert	3.1.2	already published at pub.dev
package:crypto	3.0.6	already published at pub.dev
package:fixnum	1.2.0	ready to publish	fixnum-v1.2.0
package:lints	6.0.0-wip	WIP (no publish necessary)
package:logging	1.3.0	already published at pub.dev
package:os_detect	2.0.3	already published at pub.dev
package:path	1.9.2-wip	WIP (no publish necessary)
package:platform	3.1.6	already published at pub.dev
package:typed_data	1.4.0	already published at pub.dev

Documentation at https://github.com/dart-lang/ecosystem/wiki/Publishing-automation.

[github-actions]

PR Health

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pkgs/fixnum/lib/src/intx.dart	💔 Not covered

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// Copyright (c) 2025, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
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[github-actions]

PR Health

Changelog Entry ✔️

Package	Changed Files

Changes to files need to be accounted for in their respective changelogs.

Coverage ⚠️

File	Coverage
pkgs/fixnum/lib/src/intx.dart	💔 Not covered

This check for test coverage is informational (issues shown here will not fail the PR).

This check can be disabled by tagging the PR with skip-coverage-check.

API leaks ✔️

The following packages contain symbols visible in the public API, but not exported by the library. Export these symbols or remove them from your publicly visible API.

Package	Leaked API symbols

License Headers ✔️

// Copyright (c) 2025, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

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no missing headers

All source files should start with a license header.

[eernstg]

The test coverage check fails. The page about test coverage states that "Test coverage should not decrease by introducing a PR", but I can't see how this PR would have that effect. @devoncarew, can you say something about how is this usually handled?

[devoncarew]

The test coverage check fails. The page about test coverage states that "Test coverage should not decrease by introducing a PR", but I can't see how this PR would have that effect. @devoncarew, can you say something about how is this usually handled?

The coverage check is informational. It looks like the health check is failing, and likely due to a bug in the api check tool: https://github.com/dart-lang/core/actions/runs/13566672156/job/37921655020?pr=866#step:12:159.

That check is trying to diff this current change vs. the last published one, and determine what type of semver bump should be done (major? minor? service?). I'll add a label to skip the health check for this PR.

[devoncarew]

Will leave the approve to @lrhn -

[eernstg]

Thanks!

@lrhn, do you have further comments?

[github-actions]

PR Health

Changelog Entry ✔️

Package	Changed Files

Changes to files need to be accounted for in their respective changelogs.

Coverage ⚠️

File	Coverage
pkgs/fixnum/lib/src/intx.dart	💔 Not covered

This check for test coverage is informational (issues shown here will not fail the PR).

This check can be disabled by tagging the PR with skip-coverage-check.

API leaks ✔️

The following packages contain symbols visible in the public API, but not exported by the library. Export these symbols or remove them from your publicly visible API.

Package	Leaked API symbols

License Headers ✔️

// Copyright (c) 2025, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

Files
no missing headers

All source files should start with a license header.