add unit test

cocos/gfx/base/states/sampler.ts

@@ -41,8 +41,8 @@ export class Sampler extends GFXObject {
         this._hash$ = hash;
     }
 
-    static computeHash (info: Readonly<SamplerInfo>): Filter {
-        let hash = info.minFilter;
+    static computeHash (info: Readonly<SamplerInfo>): number {
+        let hash = (info.minFilter as number);
         hash |= ((info.magFilter as number) << 2);
         hash |= ((info.mipFilter as number) << 4);
         hash |= ((info.addressU as number) << 6);

tests/core/gfx/sampler-info.test.ts

@@ -0,0 +1,46 @@
+import { Sampler, SamplerInfo, Filter, Address, ComparisonFunc } from "../../../cocos/gfx"
+
+function testSamplerInfo(info: SamplerInfo): boolean {
+    const packed = Sampler.computeHash(info);
+    const unpacked = Sampler.unpackFromHash(packed);
+    return unpacked.minFilter === info.minFilter &&
+        unpacked.magFilter === info.magFilter &&
+        unpacked.mipFilter === info.mipFilter &&
+        unpacked.addressU === info.addressU &&
+        unpacked.addressV === info.addressV &&
+        unpacked.addressW === info.addressW &&
+        unpacked.maxAnisotropy === info.maxAnisotropy &&
+        unpacked.cmpFunc === info.cmpFunc;
+}
+
+test('packSamplerInfo', () => {
+    expect(testSamplerInfo(new SamplerInfo(
+        Filter.NONE,
+        Filter.NONE,
+        Filter.NONE,
+        Address.WRAP,
+        Address.WRAP,
+        Address.WRAP,
+        0,
+        ComparisonFunc.NEVER))).toBe(true);
+
+    expect(testSamplerInfo(new SamplerInfo(
+        Filter.ANISOTROPIC,
+        Filter.ANISOTROPIC,
+        Filter.ANISOTROPIC,
+        Address.BORDER,
+        Address.BORDER,
+        Address.BORDER,
+        16,
+        ComparisonFunc.ALWAYS))).toBe(true);
+
+    expect(testSamplerInfo(new SamplerInfo(
+        Filter.ANISOTROPIC,
+        Filter.LINEAR,
+        Filter.POINT,
+        Address.BORDER,
+        Address.CLAMP,
+        Address.MIRROR,
+        15,
+        ComparisonFunc.GREATER_EQUAL))).toBe(true);
+})