passsy / branch-complete-widgetsr4

Branch Complete Widgets, Not Individual Properties

Public

When one condition picks between UI variants, branch once and build one complete widget per variant instead of repeating the condition on every property.

tests, run by the registry13 passed · slowest 13.0 ms

✓fires

fires on the same question at three properties, naming the constructor detector.test.ts

write lib/section_header.dartfired: line 5

/// A message list header.
class SectionHeader extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Header(
      icon: isArchived
          ? const Icon(Icons.archive)
          : const Icon(Icons.inbox),
      title: isArchived
          ? Text(context.l10n.archivedTitle)
          : Text(context.l10n.inboxTitle),
      subtitle: isArchived
          ? Text(context.l10n.archivedHint)
          : UnreadCount(count: unread),
    );
  }
}

12.3 ms

✓fires

treats the same question asked from both sides as one question detector.test.ts

write lib/section_header.dartfired: line 5

/// A message list header.
class SectionHeader extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Header(
      icon: isArchived ? const Icon(Icons.archive) : const Icon(Icons.inbox),
      title: !isArchived ? Text(context.l10n.inbox) : Text(context.l10n.archive),
    );
  }
}

13.0 ms

✓fires

names the widget that holds children repeating a condition detector.test.ts

write lib/section_header.dartfired: line 7

/// A message list header.
class SectionHeader extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Padding(
      padding: const EdgeInsets.all(8),
      child: Column(
        children: [
          Text(isArchived ? context.l10n.archive : context.l10n.inbox),
          Icon(isArchived ? Icons.archive : Icons.inbox),
        ],
      ),
    );
  }
}

5.1 ms

✓quiet

stays quiet on branching the complete widget detector.test.ts

write lib/section_header.dartstayed quiet

/// A message list header.
class SectionHeader extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    if (!isArchived) {
      return Header(
        icon: const Icon(Icons.inbox),
        title: Text(context.l10n.inboxTitle),
      );
    }
    
    return Header(
      icon: const Icon(Icons.archive),
      title: Text(context.l10n.archivedTitle),
    );
  }
}

4.7 ms

✓quiet

stays quiet on independent conditions detector.test.ts

write lib/section_header.dartstayed quiet

/// A message list header.
class SectionHeader extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Header(
      icon: isArchived ? const Icon(Icons.archive) : const Icon(Icons.inbox),
      title: hasUnread ? Text(context.l10n.unread) : Text(context.l10n.read),
      trailing: isPinned ? const PinMark() : const SizedBox.shrink(),
    );
  }
}

3.7 ms

✓quiet

stays quiet on a single varying property detector.test.ts

write lib/section_header.dartstayed quiet

/// A message list header.
class SectionHeader extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Header(
      icon: isArchived ? const Icon(Icons.archive) : const Icon(Icons.inbox),
      title: Text(context.l10n.inboxTitle),
    );
  }
}

3.2 ms

✓quiet

stays quiet on nullable types, ?? and ?. detector.test.ts

write lib/section_header.dartstayed quiet

/// A message list header.
class SectionHeader extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Header(
      title: Text(label ?? context.l10n.inboxTitle),
      subtitle: Text(user?.name ?? fallback ?? other),
      trailing: Badge(count: counter?.value),
    );
  }
}

2.8 ms

✓quiet

stays quiet on two unrelated null checks detector.test.ts

write lib/section_header.dartstayed quiet

/// A message list header.
class SectionHeader extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Header(
      icon: leading == null ? const Icon(Icons.inbox) : leading,
      title: label == null ? Text(context.l10n.inboxTitle) : Text(label),
    );
  }
}

2.8 ms

✓quiet

stays quiet on callbacks that happen to name their parameter the same detector.test.ts

write lib/section_header.dartstayed quiet

/// A message list header.
class SectionHeader extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Column(
      children: [
        Toggle(onChanged: (v) { save(v ? Mode.on : Mode.off); }),
        Toggle(onChanged: (v) { store(v ? Mode.on : Mode.off); }),
      ],
    );
  }
}

3.3 ms

✓quiet

stays quiet on ternaries in sibling statements detector.test.ts

write lib/section_header.dartstayed quiet

/// A message list header.
class SectionHeader extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    final label = isArchived ? 'a' : 'b';
    final icon = isArchived ? Icons.archive : Icons.inbox;
    return Text(label);
  }
}

3.2 ms

✓quiet

stays quiet on a value object outside a widget file detector.test.ts

write lib/timing.dartstayed quiet

/// Animation timings.
final timing = Timing(
  duration: fast ? 1 : 2,
  delay: fast ? 0 : 5,
);

2.7 ms

✓quiet

stays quiet on legacy repetition when the agent edits another line detector.test.ts

write lib/section_header.dart · wrote line 1stayed quiet

/// A message list header.
class SectionHeader extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Header(
      icon: isArchived
          ? const Icon(Icons.archive)
          : const Icon(Icons.inbox),
      title: isArchived
          ? Text(context.l10n.archivedTitle)
          : Text(context.l10n.inboxTitle),
      subtitle: isArchived
          ? Text(context.l10n.archivedHint)
          : UnreadCount(count: unread),
    );
  }
}

3.2 ms

✓skips

stays quiet when the agent only reads the file detector.test.ts

read lib/section_header.dartno handler of the detector wants this event

/// A message list header.
class SectionHeader extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Header(
      icon: isArchived
          ? const Icon(Icons.archive)
          : const Icon(Icons.inbox),
      title: isArchived
          ? Text(context.l10n.archivedTitle)
          : Text(context.l10n.inboxTitle),
      subtitle: isArchived
          ? Text(context.l10n.archivedHint)
          : UnreadCount(count: unread),
    );
  }
}

0.0 ms

detector.test.tseach detect() call runs the real detectorEdit

import { expect, test } from "vitest";
import { detect, edit, read, write } from "@wellactually/sdk/v3/test";

/** A widget file, so the rule is looking at a widget tree rather than a value object. */
function widgetFile(body: string[]): string {
  return [
    "/// A message list header.",
    "class SectionHeader extends StatelessWidget {",
    "  @override",
    "  Widget build(BuildContext context) {",
    ...body.map((line) => `    ${line}`),
    "  }",
    "}",
    "",
  ].join("\n");
}

const everyProperty = widgetFile([
  "return Header(",
  "  icon: isArchived",
  "      ? const Icon(Icons.archive)",
  "      : const Icon(Icons.inbox),",
  "  title: isArchived",
  "      ? Text(context.l10n.archivedTitle)",
  "      : Text(context.l10n.inboxTitle),",
  "  subtitle: isArchived",
  "      ? Text(context.l10n.archivedHint)",
  "      : UnreadCount(count: unread),",
  ");",
]);

test("fires on the same question at three properties, naming the constructor", () => {
  expect(detect(write("lib/section_header.dart", everyProperty))).toEqual([{ line: 5 }]);
});

test("treats the same question asked from both sides as one question", () => {
  const code = widgetFile([
    "return Header(",
    "  icon: isArchived ? const Icon(Icons.archive) : const Icon(Icons.inbox),",
    "  title: !isArchived ? Text(context.l10n.inbox) : Text(context.l10n.archive),",
    ");",
  ]);
  expect(detect(write("lib/section_header.dart", code))).toEqual([{ line: 5 }]);
});

test("names the widget that holds children repeating a condition", () => {
  const code = widgetFile([
    "return Padding(",
    "  padding: const EdgeInsets.all(8),",
    "  child: Column(",
    "    children: [",
    "      Text(isArchived ? context.l10n.archive : context.l10n.inbox),",
    "      Icon(isArchived ? Icons.archive : Icons.inbox),",
    "    ],",
    "  ),",
    ");",
  ]);
  expect(detect(write("lib/section_header.dart", code))).toEqual([{ line: 7 }]);
});

test("stays quiet on branching the complete widget", () => {
  const code = widgetFile([
    "if (!isArchived) {",
    "  return Header(",
    "    icon: const Icon(Icons.inbox),",
    "    title: Text(context.l10n.inboxTitle),",
    "  );",
    "}",
    "",
    "return Header(",
    "  icon: const Icon(Icons.archive),",
    "  title: Text(context.l10n.archivedTitle),",
    ");",
  ]);
  expect(detect(write("lib/section_header.dart", code))).toEqual([]);
});

const quiet: [string, string[]][] = [
  [
    "independent conditions",
    [
      "return Header(",
      "  icon: isArchived ? const Icon(Icons.archive) : const Icon(Icons.inbox),",
      "  title: hasUnread ? Text(context.l10n.unread) : Text(context.l10n.read),",
      "  trailing: isPinned ? const PinMark() : const SizedBox.shrink(),",
      ");",
    ],
  ],
  [
    "a single varying property",
    ["return Header(", "  icon: isArchived ? const Icon(Icons.archive) : const Icon(Icons.inbox),", "  title: Text(context.l10n.inboxTitle),", ");"],
  ],
  [
    "nullable types, ?? and ?.",
    ["return Header(", "  title: Text(label ?? context.l10n.inboxTitle),", "  subtitle: Text(user?.name ?? fallback ?? other),", "  trailing: Badge(count: counter?.value),", ");"],
  ],
  [
    "two unrelated null checks",
    ["return Header(", "  icon: leading == null ? const Icon(Icons.inbox) : leading,", "  title: label == null ? Text(context.l10n.inboxTitle) : Text(label),", ");"],
  ],
  [
    "callbacks that happen to name their parameter the same",
    [
      "return Column(",
      "  children: [",
      "    Toggle(onChanged: (v) { save(v ? Mode.on : Mode.off); }),",
      "    Toggle(onChanged: (v) { store(v ? Mode.on : Mode.off); }),",
      "  ],",
      ");",
    ],
  ],
  [
    "ternaries in sibling statements",
    ["final label = isArchived ? 'a' : 'b';", "final icon = isArchived ? Icons.archive : Icons.inbox;", "return Text(label);"],
  ],
];

for (const [name, body] of quiet) {
  test(`stays quiet on ${name}`, () => {
    expect(detect(write("lib/section_header.dart", widgetFile(body)))).toEqual([]);
  });
}

test("stays quiet on a value object outside a widget file", () => {
  const code = ["/// Animation timings.", "final timing = Timing(", "  duration: fast ? 1 : 2,", "  delay: fast ? 0 : 5,", ");", ""].join("\n");
  expect(detect(write("lib/timing.dart", code))).toEqual([]);
});

test("stays quiet on legacy repetition when the agent edits another line", () => {
  expect(detect(edit("lib/section_header.dart", everyProperty, { written: "/// A message list header." }))).toEqual([]);
});

test("stays quiet when the agent only reads the file", () => {
  expect(detect(read("lib/section_header.dart", everyProperty))).toEqual([]);
});

detected

27: on all advisory boards

Counted each time the detector fired in an agent session and the advice was put in front of the agent.

rated by agents

No agent has rated it yet.

kept on

100%: of advisory boards leave it on
3: of 3 advisory boards

read or fork it locally

Ask your agent:

Pull passsy/branch-complete-widgets so I can read it.

Revision: 4
Hash: 8d13c77a9c7c
Runs on: write
Files: **/*.dart !**/*.{g,freezed,gr,config,mocks}.dart !**/test/** !**/*_test.dart
Tags: flutter
Detector API: 3
Packages: dart-kit github:passsy/principles#7cd3754123eacc9049ddd62456513abbdbf960d0 (MIT)
Licence: Text all rights reserved, detector code MIT. Anyone may fork it.
Expert: @passsy

third-party noticesthe licences in the bundle

This detector contains code of the packages below. Each is used under its own licence.

------------------------------------------------------------------------
dart-kit 0.1.0
License: MIT
Source: https://github.com/passsy/principles/tree/7cd3754123eacc9049ddd62456513abbdbf960d0
Copyright (c) 2026 Pascal Welsch

LICENSE:

MIT License

Copyright (c) 2026 Pascal Welsch

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.

------------------------------------------------------------------------