Revert lint plugin to .js (oxlint uses Node.js internally), add new rules

Oxlint's JS plugin loader uses Node.js, not Bun — .ts fails in CI
with ERR_UNKNOWN_FILE_EXTENSION.

New rules:
- no-hand-rolled-color: flags rgba()/rgb() in template literals outside
  color.ts — use colorToCSS()/colorToHex() helpers instead
- typescript/no-unnecessary-boolean-literal-compare
- typescript/no-unnecessary-template-expression
- typescript/no-unnecessary-type-arguments
- unicorn/no-useless-fallback-in-spread
- unicorn/no-length-as-slice-end
- unicorn/no-unnecessary-await
- unicorn/prefer-string-starts-ends-with

Fixed violations: visible !== false → fill.visible in analyze.ts,
removed ?? {} fallbacks in style-runs.ts spread.

lint/plugin.js

@@ -121,12 +121,39 @@ const noMathRandom = {
   },
 }
 
+const noHandRolledColor = {
+  meta: {
+    docs: {
+      description:
+        'Disallow hand-rolled color conversions — use helpers from color.ts (colorToCSS, colorToHex, parseColor, etc.)',
+    },
+  },
+  create(context) {
+    const file = context.filename ?? context.getFilename?.()
+    if (file?.endsWith('color.ts') || file?.endsWith('color.js')) return {}
+
+    return {
+      TemplateLiteral(node) {
+        const raw = context.sourceCode.getText(node)
+        if (/rgba?\s*\(/.test(raw)) {
+          context.report({
+            node,
+            message: "Use colorToCSS() or colorToHex() from color.ts instead of hand-rolled rgba()/rgb() strings.",
+          })
+        }
+      },
+
+    }
+  },
+}
+
 const plugin = {
   meta: { name: 'open-pencil' },
   rules: {
     'no-inline-named-types': noInlineNamedTypes,
     'no-structuredclone-scene-arrays': noStructuredCloneSceneArrays,
     'no-math-random': noMathRandom,
+    'no-hand-rolled-color': noHandRolledColor,
   },
 }
 

oxlint.json

@@ -1,7 +1,7 @@
 {
   "$schema": "./node_modules/oxlint/configuration_schema.json",
   "plugins": ["typescript", "import", "unicorn", "vue"],
-  "jsPlugins": ["./lint/plugin.ts"],
+  "jsPlugins": ["./lint/plugin.js"],
   "env": {
     "browser": true,
     "es2024": true
@@ -31,6 +31,9 @@
     "typescript/no-unnecessary-condition": "error",
     "typescript/no-unnecessary-type-assertion": "error",
     "typescript/no-unnecessary-type-parameters": "error",
+    "typescript/no-unnecessary-boolean-literal-compare": "error",
+    "typescript/no-unnecessary-template-expression": "error",
+    "typescript/no-unnecessary-type-arguments": "error",
     "typescript/prefer-optional-chain": "error",
     "typescript/prefer-for-of": "error",
 
@@ -42,6 +45,11 @@
     "unicorn/no-instanceof-array": "error",
     "unicorn/no-typeof-undefined": "error",
     "unicorn/no-nested-ternary": "error",
+
+    "unicorn/no-useless-fallback-in-spread": "error",
+    "unicorn/no-length-as-slice-end": "error",
+    "unicorn/no-unnecessary-await": "error",
+    "unicorn/prefer-string-starts-ends-with": "error",
     "unicorn/consistent-existence-index-check": "error",
 
     "vue/no-arrow-functions-in-watch": "error",
@@ -66,7 +74,8 @@
       "Matrix": "m00:number,m01:number,m02:number,m10:number,m11:number,m12:number"
     }],
     "open-pencil/no-structuredclone-scene-arrays": "error",
-    "open-pencil/no-math-random": "error"
+    "open-pencil/no-math-random": "error",
+    "open-pencil/no-hand-rolled-color": "error"
   },
   "overrides": [
     {

packages/core/src/style-runs.ts

@@ -13,7 +13,7 @@ function expandRuns(runs: StyleRun[], textLength: number): (CharacterStyleOverri
   const chars: (CharacterStyleOverride | null)[] = new Array(textLength).fill(null)
   for (const run of runs) {
     for (let i = run.start; i < run.start + run.length && i < textLength; i++) {
-      chars[i] = { ...(chars[i] ?? {}), ...run.style }
+      chars[i] = { ...chars[i], ...run.style }
     }
   }
   return chars
@@ -29,7 +29,7 @@ export function applyStyleToRange(
   const chars = expandRuns(runs, textLength)
 
   for (let i = start; i < end && i < textLength; i++) {
-    chars[i] = { ...(chars[i] ?? {}), ...patch }
+    chars[i] = { ...chars[i], ...patch }
   }
 
   return compactRuns(chars)

packages/core/src/tools/analyze.ts

@@ -38,10 +38,10 @@ function serializeNodeProps(raw: SceneNode): string {
   lines.push(`size: ${raw.width} ${raw.height}`)
   lines.push(`pos: ${raw.x} ${raw.y}`)
 
-  const solidFill = raw.fills.find((f) => f.type === 'SOLID' && f.visible !== false)
+  const solidFill = raw.fills.find((f) => f.type === 'SOLID' && f.visible)
   if (solidFill) lines.push(`fill: ${colorToHex(solidFill.color)}`)
 
-  const solidStroke = raw.strokes.find((s) => s.visible !== false)
+  const solidStroke = raw.strokes.find((s) => s.visible)
   if (solidStroke) {
     lines.push(`stroke: ${colorToHex(solidStroke.color)}`)
     if (solidStroke.weight) lines.push(`strokeWeight: ${solidStroke.weight}`)
@@ -155,12 +155,12 @@ export const analyzeColors = defineTool({
 
       const boundVars = raw.boundVariables
       for (const fill of raw.fills) {
-        if (fill.type === 'SOLID' && fill.visible !== false) {
+        if (fill.type === 'SOLID' && fill.visible) {
           trackColor(colorMap, fill.color, boundVars?.['fills'] ? String(boundVars['fills']) : null)
         }
       }
       for (const stroke of raw.strokes) {
-        if (stroke.visible !== false) {
+        if (stroke.visible) {
           trackColor(colorMap, stroke.color, boundVars?.['strokes'] ? String(boundVars['strokes']) : null)
         }
       }