`@container style(--theme: dark)` never matches: style container queries are dropped

Start with parseContainerCondition in src/compiler/container-query.ts and ContainerContextValue in src/native/reactivity.ts, then inspect how VariableContext exposes container variables. Run the reproducer with yarn jest src/__tests__/native/container-style-query.test.tsx; done means all four cases pass for set and unset --theme values.

Before submitting a new issue

• I tested using the latest version of the library, as the bug might be already fixed.
• I tested using a supported version of react native.
• I checked for possible duplicate issues, with possible answers.

Bug summary

A style container query compares the query container's computed value of the property it names (CSS Conditional 5 §6.2). Chromium 156, Firefox 157 and WebKit 27.2 evaluate one over a custom property, so @container style(--theme: dark) matches inside a container that sets --theme: dark, and @container not style(--theme: dark) inside one that leaves it unset. parseContainerCondition (src/compiler/container-query.ts) returns nothing for a style condition (// We don't support these yet), so neither rule ever applies, and a container's ContainerContextValue (src/native/reactivity.ts) carries no variables to compare with.

#451's container-rejection tests pin the rejection. #426 compiles style() to an unknown term (MQ5 §3.1) and lists the query itself among its known limits. Answering one means handing the container evaluator the container's variable scope, the one VariableContext provides its descendants.

Library version

main at 2421ea7 (0.0.0-nightly.2421ea7)

Environment info

System:
  OS: Windows 11 10.0.26300
  CPU: "(32) x64 AMD Ryzen 9 9950X3D 16-Core Processor          "
  Memory: 155.26 GB / 255.67 GB
Binaries:
  Node:
    version: 26.12.1
    path: C:\Program Files\nodejs\node.EXE
  Yarn:
    version: 4.9.2
    path: C:\Users\<user>\AppData\Roaming\npm\yarn.CMD
  npm:
    version: 12.2.1
    path: C:\Program Files\nodejs\npm.CMD
  Watchman: Not Found
SDKs:
  Android SDK:
    API Levels:
      - "33"
      - "35"
      - "35"
      - "35"
      - "36"
      - "37"
    Build Tools:
      - 35.0.0
      - 36.0.0
      - 36.1.0
      - 37.0.0
    System Images:
      - android-26 | Google APIs Intel x86_64 Atom
      - android-28 | Google APIs Intel x86_64 Atom
      - android-29 | Google APIs Intel x86_64 Atom
      - android-30 | Google APIs Intel x86_64 Atom
      - android-31 | Google APIs Intel x86_64 Atom
      - android-32 | Google APIs Intel x86_64 Atom
      - android-33 | Google APIs Intel x86_64 Atom
      - android-34 | Google APIs Intel x86_64 Atom
      - android-35 | Google APIs Intel x86_64 Atom
      - android-36.1 | Google Play Intel x86_64 Atom
      - android-36.1 | Pre-Release 16 KB Page Size Google Play Intel x86_64 Atom
      - android-37.0 | Google APIs Intel x86_64 Atom
    Android NDK: Not Found
  Windows SDK: Not Found
IDEs:
  Android Studio: AI-262.9437.185.2621.16467767
  Visual Studio: Not Found
Languages:
  Java:
    version: 17.0.20.1
    path: C:\Program Files\Microsoft\jdk-17.0.20.101-hotspot\bin\javac.EXE
  Ruby: Not Found
npmPackages:
  "@react-native-community/cli": Not Found
  react:
    installed: 19.2.3
    wanted: 19.2.3
  react-native:
    installed: 0.86.3
    wanted: 0.86.3
  react-native-windows: Not Found
npmGlobalPackages:
  "*react-native*": Not Found
Android:
  hermesEnabled: Not found
  newArchEnabled: Not found
iOS:
  hermesEnabled: Not found
  newArchEnabled: Not found

Steps to reproduce

1. Clone the reproducer branch, which is main at 2421ea7 with one file added, src/__tests__/native/container-style-query.test.tsx, and install:

   git clone --branch repro/513-container-style-query https://github.com/YevheniiKotyrlo/react-native-css
   cd react-native-css
   yarn install
   

2. Run yarn jest src/__tests__/native/container-style-query.test.tsx.

src/__tests__/native/container-style-query.test.tsx:

// A style() container query compares the container's computed custom property (CSS Conditional 5 §7.3); --theme is dark on the parent and unset on the other
import { fireEvent, render, screen } from "@testing-library/react-native";
import { View } from "react-native-css/components/View";
import { registerCSS } from "react-native-css/jest";

test.each([
  ["dark-parent", "style(--theme: dark)", true],
  ["dark-parent", "not style(--theme: dark)", false],
  ["plain-parent", "style(--theme: dark)", false],
  ["plain-parent", "not style(--theme: dark)", true],
])("in a %s, @container %s matches: %s", (parent, condition, expected) => {
  registerCSS(
    `
    .dark-parent { container-type: size; --theme: dark; }
    .plain-parent { container-type: size; }
    .child { width: 10px; }
    @container ${condition} { .child { width: 37px; } }
  `,
    { inlineVariables: false },
  );
  render(
    <View testID="parent" className={parent}>
      <View testID="child" className="child" />
    </View>,
  );
  fireEvent(screen.getByTestId("parent"), "layout", {
    nativeEvent: { layout: { x: 0, y: 0, width: 400, height: 200 } },
  });
  expect(screen.getByTestId("child").props.style.width === 37).toBe(expected);
});

Expected: @container style(--theme: dark) matches inside the container that sets --theme: dark, and @container not style(--theme: dark) inside the one that leaves it unset.

Actual: neither rule ever applies.

FAIL src/__tests__/native/container-style-query.test.tsx
  × in a dark-parent, @container style(--theme: dark) matches: true (24 ms)
  √ in a dark-parent, @container not style(--theme: dark) matches: false (5 ms)
  √ in a plain-parent, @container style(--theme: dark) matches: false (1 ms)
  × in a plain-parent, @container not style(--theme: dark) matches: true (2 ms)
  ● in a dark-parent, @container style(--theme: dark) matches: true
    expect(received).toBe(expected) // Object.is equality
    Expected: true
    Received: false
      27 |     nativeEvent: { layout: { x: 0, y: 0, width: 400, height: 200 } },
      28 |   });
    > 29 |   expect(screen.getByTestId("child").props.style.width === 37).toBe(expected);
         |                                                                ^
      30 | });
      31 |
      at toBe (src/__tests__/native/container-style-query.test.tsx:29:64)
  ● in a plain-parent, @container not style(--theme: dark) matches: true
    expect(received).toBe(expected) // Object.is equality
    Expected: true
    Received: false
      27 |     nativeEvent: { layout: { x: 0, y: 0, width: 400, height: 200 } },
      28 |   });
    > 29 |   expect(screen.getByTestId("child").props.style.width === 37).toBe(expected);
         |                                                                ^
      30 | });
      31 |
      at toBe (src/__tests__/native/container-style-query.test.tsx:29:64)
Test Suites: 1 failed, 1 total
Tests:       2 failed, 2 passed, 4 total
Snapshots:   0 total
Time:        1.117 s, estimated 3 s
Ran all test suites matching /src\\__tests__\\native\\container-style-query.test.tsx/i.

Reproducible example repository

https://github.com/YevheniiKotyrlo/react-native-css/tree/repro/513-container-style-query