chore: add FreeRange range-analysis check

.github/workflows/ci.yml

@@ -240,6 +240,23 @@ jobs:
       - name: Run typecheck
         run: pnpm typecheck
 
+  freerange:
+    name: FreeRange
+    runs-on: ubuntu-latest
+    timeout-minutes: 20
+    steps:
+      - name: Checkout
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+
+      - name: Setup toolchain
+        uses: ./.github/actions/setup-node-pnpm
+
+      - name: Setup Bun
+        uses: oven-sh/setup-bun@0c5077e51419868618aeaa5fe8019c62421857d6 # v2.2.0
+
+      - name: Check numeric ranges
+        run: pnpm check:freerange
+
   integration:
     name: Integration Tests
     runs-on: ubuntu-latest

package.json

@@ -120,6 +120,7 @@
     "check:layering": "node --experimental-strip-types --test scripts/layering/model.test.ts && node --experimental-strip-types scripts/layering/check.ts",
     "check:production-exports": "fallow dead-code --config fallow-production-exports.json --production --unused-exports --fail-on-issues",
     "check:bundle-owner-files": "node --experimental-strip-types scripts/check-bundle-owner-files.ts",
+    "check:freerange": "fr",
     "check:quick": "pnpm lint && pnpm typecheck",
     "sync:mcp-metadata": "node scripts/sync-mcp-metadata.mjs",
     "check:mcp-metadata": "node scripts/sync-mcp-metadata.mjs --check",
@@ -224,15 +225,16 @@
     "yaml": "^2.9.0"
   },
   "devDependencies": {
+    "@chenglou/freerange": "^0.0.1",
     "@types/node": "^22.19.21",
-    "typescript": "^7.0.2",
     "@vitest/coverage-v8": "4.1.8",
     "fallow": "^2.95.0",
     "oxc-parser": "^0.138.0",
     "oxfmt": "^0.42.0",
     "oxlint": "^1.69.0",
     "skillgym": "^0.9.1",
     "tsdown": "^0.22.4",
+    "typescript": "^7.0.2",
     "vite": "^8.0.16",
     "vitest": "^4.1.8"
   }

pnpm-workspace.yaml

@@ -5,3 +5,5 @@ pmOnFail: warn
 verifyDepsBeforeRun: warn
 allowBuilds:
   fallow: true
+minimumReleaseAgeExclude:
+  - '@chenglou/freerange@0.0.1'

src/contracts/scroll-gesture.test.ts

@@ -221,3 +221,7 @@ test('clampGestureCoordinate rounds values and clamps them into the safe gesture
   assert.equal(clampGestureCoordinate(2.6, 8, 100), 8);
   assert.equal(clampGestureCoordinate(97.6, 8, 100), 92);
 });
+
+test('clampGestureCoordinate returns the lower bound for non-finite coordinates', () => {
+  assert.equal(clampGestureCoordinate(Number.POSITIVE_INFINITY, 8, 100), 8);
+});

src/contracts/scroll-gesture.ts

@@ -241,9 +241,11 @@ function pointFromPercent(
   xPercent: number,
   yPercent: number,
 ): GesturePoint {
+  const x = Math.trunc((frame.referenceWidth * xPercent) / 100);
+  const y = Math.trunc((frame.referenceHeight * yPercent) / 100);
   return {
-    x: Math.trunc((frame.referenceWidth * xPercent) / 100),
-    y: Math.trunc((frame.referenceHeight * yPercent) / 100),
+    x: Number.isFinite(x) ? x : 0,
+    y: Number.isFinite(y) ? y : 0,
   };
 }
 
@@ -307,11 +309,11 @@ function normalizeRequestedPixels(pixels: number): number {
 }
 
 export function clampGestureCoordinate(value: number, marginPx: number, size: number): number {
-  const min = marginPx;
-  const max = Math.max(min, size - marginPx);
-  return clampToRange(value, min, max);
-}
+  const min = Math.round(marginPx);
+  if (!Number.isFinite(min)) return 0;
+
+  const max = Math.max(min, Math.round(size - marginPx));
+  if (!Number.isFinite(max) || !Number.isFinite(value)) return min;
 
-function clampToRange(value: number, min: number, max: number): number {
-  return Math.min(Math.round(max), Math.max(Math.round(min), Math.round(value)));
+  return Math.min(max, Math.max(min, Math.round(value)));
 }

src/daemon/handlers/record-trace-android.ts

@@ -215,7 +215,13 @@ function scaledSizeToMax(size: AndroidRecordingSize & { maxSize: number }): Andr
   if (longest <= size.maxSize) {
     return { width: size.width, height: size.height };
   }
+  if (longest === 0) {
+    return { width: size.width, height: size.height };
+  }
   const scale = size.maxSize / longest;
+  if (!Number.isFinite(scale)) {
+    return { width: size.width, height: size.height };
+  }
   return {
     width: scaledEvenDimension(size.width, scale),
     height: scaledEvenDimension(size.height, scale),

src/screenshot-diff/screenshot-diff-region-overlay.ts

@@ -18,10 +18,12 @@ export function annotateDiffRegions(diff: PNG, regions: ScreenshotDiffRegion[]):
 }
 
 function drawRect(diff: PNG, rect: ScreenshotDiffRegion['rect']): void {
-  const minX = clamp(rect.x, 0, diff.width - 1);
-  const minY = clamp(rect.y, 0, diff.height - 1);
-  const maxX = clamp(rect.x + rect.width - 1, 0, diff.width - 1);
-  const maxY = clamp(rect.y + rect.height - 1, 0, diff.height - 1);
+  const bounds = resolveFiniteRectBounds(rect);
+  if (bounds == null) return;
+  const minX = clamp(bounds.x, 0, diff.width - 1);
+  const minY = clamp(bounds.y, 0, diff.height - 1);
+  const maxX = clamp(bounds.right, 0, diff.width - 1);
+  const maxY = clamp(bounds.bottom, 0, diff.height - 1);
   for (let thickness = 0; thickness < REGION_BORDER_THICKNESS; thickness += 1) {
     for (let x = minX; x <= maxX; x += 1) {
       setPixel(diff, x, minY + thickness, REGION_BORDER_COLOR);
@@ -34,6 +36,19 @@ function drawRect(diff: PNG, rect: ScreenshotDiffRegion['rect']): void {
   }
 }
 
+function resolveFiniteRectBounds(rect: ScreenshotDiffRegion['rect']): {
+  x: number;
+  y: number;
+  right: number;
+  bottom: number;
+} | null {
+  const right = rect.x + rect.width - 1;
+  const bottom = rect.y + rect.height - 1;
+  const values = [rect.x, rect.y, rect.width, rect.height, right, bottom];
+  if (!values.every(Number.isFinite)) return null;
+  return { x: rect.x, y: rect.y, right, bottom };
+}
+
 function setPixel(
   diff: PNG,
   x: number,
@@ -49,5 +64,6 @@ function setPixel(
 }
 
 function clamp(value: number, min: number, max: number): number {
+  if (!Number.isFinite(value)) return min;
   return Math.min(Math.max(value, min), max);
 }