theme.important override

theme.important-override

Rule ID: theme.important-override Severity: ERROR Category: theme Target Standards: W3C Cascading Style Sheets (CSS) Specificity Level 4, Tailwind CSS Design Token Architecture

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1. Overview & Core Invariant

Detects !important modifiers on color utility classes that break theme cascade and specificity hierarchy

Core Invariant:

"Color utility classes must never use the !important modifier (!bg-, !text-); specificity must be managed via CSS Cascade Layers."

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2. Technical Grounding & Engine Realities

Using the ! modifier (e.g. !bg-red-500 or !text-white) forcefully escalates CSS declaration priority above normal cascade layers.

1. Destroys Theme Inversion: Dark mode variants (.dark bg-card) cannot override !bg-white without also adding !dark:bg-card, sparking an !important arms race.
2. Compromises Component Reusability: Reusable components with !important color classes cannot be customized or themed by parent containers.
3. Unpredictable State Styling: Hover, focus, and disabled state colors fail to trigger reliably when base colors are marked !important.

Charites enforces relying on Cascade Layers (@layer components, utilities) and semantic token definitions.

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3. Vulnerability & Risk Taxonomy

Risk Vector	Severity	Impact
Cascade Arms Race	HIGH	Forces downstream theme overrides to duplicate !important, breaking modular CSS encapsulation.
Dark Mode Override Failure	HIGH	Dark mode variants fail to override base !important styles, resulting in inverted visual glitches.

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4. Non-Compliant Code Patterns (Bad Examples)

ASTRO (!important modifier on background and text color):

<button class="!bg-red-500 !text-white">Delete</button>

TSX (!important on semantic and hover colors in JSX):

export function Action() {
  return <div className="hover:!bg-primary !border-border">Action</div>;
}

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5. Compliant Implementation Patterns (Good Examples)

ASTRO (Proper layer-based specificity without !important):

<button class="bg-destructive text-destructive-foreground">Delete</button>

TSX (Clean semantic classes with natural CSS cascade):

export function Action() {
  return <div className="hover:bg-primary border-border">Action</div>;
}

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6. Detection & Verification Pipeline (How The Rule Evaluates Code)

This theme rule evaluates source templates against the project's design token graph:

flowchart TD
    Node["AST Node (Astro / TSX element)"] --> Extract["1. Extract Class Names (e.g. 'hover:bg-primary/10')"]
    Extract --> Strip["2. Strip Variants (hover:, dark:, sm:) -> 'bg-primary/10'"]
    Strip --> Split["3. Split Opacity Modifier -> Utility: 'bg-primary', Opacity: '/10'"]
    Split --> Convention["4. Query TokenConvention (Candidate: '--color-primary-light')"]
    Convention --> GraphQuery{"5. Check Token Graph (Does token exist in active scope?)"}
    GraphQuery -- "No (Banana Test)" --> Safe["Pass (Valid Custom / Untokenized Color)"]
    GraphQuery -- "Yes (Official Token Exists)" --> IgnoreCheck{"6. Check charites:ignore directive"}
    IgnoreCheck -- "Ignored" --> Safe
    IgnoreCheck -- "Not Ignored" --> Diag["7. Emit Diagnostic: theme.important-override with Replacement Suggestion"]

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Step-by-Step Evaluation:

1. AST Node Traversal: internal/analyzer streams JSX/Astro AST elements to the rule's Evaluate visitor.
2. Variant Normalization: Strips responsive (sm:, md:), interaction state (hover:, focus:), and theme (dark:) prefixes to isolate the core utility class.
3. Modifier Extraction: Parses utility segments and extracts slash opacity modifiers.
4. Token Convention Resolution: Consults the TokenConvention adapter to determine the official semantic design token replacement candidate.
5. Token Graph Verification (Banana Test): Queries token.Context to verify that the candidate token is declared in global.css or tokens.json within the element's scope. If not declared, the custom value is permitted without a false-positive diagnostic.
6. Directive Suppression Check: Inspects preceding AST comments for charites:ignore theme.important-override.
7. Diagnostic Emission: Produces a structured diagnostic with line number, column span, and actionable replacement suggestion.

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7. Verification & Test Harness (How The Test Works: 1-SSOT Tri-Corpus)

This rule is rigorously tested and validated across the canonical 1-SSOT Tri-Corpus in tests/correctness/theme.important-override/:

flowchart TD
    subgraph GoldenCorpus ["1-SSOT Tri-Corpus Test Matrix for theme.important-override"]
        subgraph P ["Positive Corpus (tests/correctness/theme.important-override/positive/)"]
            P1["P1: Obvious Direct Violation"]
            P2["P2: Indirect / Variant Concatenation"]
            P3["P3: Helper / clsx / cn Wrapper"]
            P4["P4: Deeply Nested Elements"]
            P5["P5: Aliased Imports / Re-exports"]
        end
        subgraph N ["Negative Corpus (tests/correctness/theme.important-override/negative/)"]
            N1["N1: Valid Design Tokens"]
            N2["N2: Explicit charites:ignore Directive"]
            N3["N3: Third-Party / Vendor Components"]
            N4["N4: Clean Semantic HTML"]
            N5["N5: Untokenized Custom Values (Banana Test)"]
        end
        subgraph A ["Adversarial Corpus (tests/correctness/theme.important-override/adversarial/)"]
            A1["A1: Template Literal Interpolations"]
            A2["A2: Ternary Conditional Expressions"]
            A3["A3: Spread Properties & Dynamic Overrides"]
            A4["A4: Dynamic Object Class Syntax"]
            A5["A5: Shadowed Variable Identifiers"]
            A6["A6: Nested Closures & HOC Wrappers"]
            A7["A7: Obfuscated Classes & Cyclic Tokens"]
        end
    end

    P --> TestRunner["Automated Runner (rule_test.go)"]
    N --> TestRunner
    A --> TestRunner
    TestRunner --> Gates["Quality Gates: Zero Panic, Zero False-Positive, Zero Bypass"]

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• Positive Fixtures (P1-P5): Verified to trigger diagnostics at exact lines and column spans.
• Negative Fixtures (N1-N5): Verified to produce zero diagnostics on valid tokens and legitimate exemptions.
• Adversarial Fixtures (A1-A7): Verified to prevent evasion across dynamic expressions, string interpolations, and cyclic references.

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8. How to Suppress (Ignore Directives)

If this pattern is required for an intentional exception, suppress the diagnostic using the canonical Charites Rule ID:

<!-- charites:ignore theme.important-override intentional exception -->

// charites:ignore theme.important-override intentional exception

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9. Configuration Reference (charites.yaml)

rules:
  theme.important-override:
    severity: error # error | warn | info | off