test: set up vitest & add tests

.gitignore

@@ -12,4 +12,7 @@ dist/
 .cache
 .output
 .env
-.eslintcache
+.eslintcache
+
+# vitest
+coverage

package.json

@@ -58,10 +58,12 @@
   "devDependencies": {
     "@eslint/js": "^9.23.0",
     "@size-limit/preset-small-lib": "^11.2.0",
+    "@vitest/coverage-v8": "3.0.8",
     "esbuild": "^0.25.0",
     "eslint": "^9.22.0",
     "eslint-plugin-jsdoc": "^50.6.3",
     "globals": "^16.0.0",
+    "happy-dom": "^17.4.4",
     "husky": "^9.1.7",
     "netlify-cli": "^19.0.2",
     "prettier": "^3.5.3",

pnpm-lock.yaml

@@ -14,6 +14,9 @@ importers:
       '@size-limit/preset-small-lib':
         specifier: ^11.2.0
         version: 11.2.0(size-limit@11.2.0)
+      '@vitest/coverage-v8':
+        specifier: 3.0.8
+        version: 3.0.8(vitest@3.0.8(@types/node@22.13.10)(happy-dom@17.4.4)(jiti@2.4.2)(terser@5.39.0)(yaml@2.7.0))
       esbuild:
         specifier: ^0.25.0
         version: 0.25.0
@@ -26,6 +29,9 @@ importers:
       globals:
         specifier: ^16.0.0
         version: 16.0.0
+      happy-dom:
+        specifier: ^17.4.4
+        version: 17.4.4
       husky:
         specifier: ^9.1.7
         version: 9.1.7
@@ -49,7 +55,7 @@ importers:
         version: 5.8.2
       vitest:
         specifier: ^3.0.8
-        version: 3.0.8(@types/node@22.13.10)(jiti@2.4.2)(terser@5.39.0)(yaml@2.7.0)
+        version: 3.0.8(@types/node@22.13.10)(happy-dom@17.4.4)(jiti@2.4.2)(terser@5.39.0)(yaml@2.7.0)
 
   site:
     dependencies:
@@ -62,6 +68,10 @@ importers:
 
 packages:
 
+  '@ampproject/remapping@2.3.0':
+    resolution: {integrity: sha512-30iZtAPgz+LTIYoeivqYo853f02jBYSd5uGnGpkFV0M3xOt9aN73erkgYAmZU43x4VfqcnLxW9Kpg3R5LC4YYw==}
+    engines: {node: '>=6.0.0'}
+
   '@babel/code-frame@7.26.2':
     resolution: {integrity: sha512-RJlIHRueQgwWitWgF8OdFYGZX328Ax5BCemNGlqHfplnRT9ESi8JkFlvaVYbS+UubVY6dpv87Fs2u5M29iNFVQ==}
     engines: {node: '>=6.9.0'}
@@ -74,15 +84,28 @@ packages:
     resolution: {integrity: sha512-Ed61U6XJc3CVRfkERJWDz4dJwKe7iLmmJsbOGu9wSloNSFttHV0I8g6UAgb7qnK5ly5bGLPd4oXZlxCdANBOWQ==}
     engines: {node: '>=6.9.0'}
 
+  '@babel/parser@7.26.10':
+    resolution: {integrity: sha512-6aQR2zGE/QFi8JpDLjUZEPYOs7+mhKXm86VaKFiLP35JQwQb6bwUE+XbvkH0EptsYhbNBSUGaUBLKqxH1xSgsA==}
+    engines: {node: '>=6.0.0'}
+    hasBin: true
+
   '@babel/parser@7.26.9':
     resolution: {integrity: sha512-81NWa1njQblgZbQHxWHpxxCzNsa3ZwvFqpUg7P+NNUU6f3UU2jBEg4OlF/J6rl8+PQGh1q6/zWScd001YwcA5A==}
     engines: {node: '>=6.0.0'}
     hasBin: true
 
+  '@babel/types@7.26.10':
+    resolution: {integrity: sha512-emqcG3vHrpxUKTrxcblR36dcrcoRDvKmnL/dCL6ZsHaShW80qxCAcNhzQZrpeM765VzEos+xOi4s+r4IXzTwdQ==}
+    engines: {node: '>=6.9.0'}
+
   '@babel/types@7.26.9':
     resolution: {integrity: sha512-Y3IR1cRnOxOCDvMmNiym7XpXQ93iGDDPHx+Zj+NM+rg0fBaShfQLkg+hKPaZCEvg5N/LeCo4+Rj/i3FuJsIQaw==}
     engines: {node: '>=6.9.0'}
 
+  '@bcoe/v8-coverage@1.0.2':
+    resolution: {integrity: sha512-6zABk/ECA/QYSCQ1NGiVwwbQerUCZ+TQbp64Q3AgmfNvurHH0j8TtXa1qbShXA6qqkpAj4V5W8pP6mLe1mcMqA==}
+    engines: {node: '>=18'}
+
   '@bugsnag/browser@7.25.0':
     resolution: {integrity: sha512-PzzWy5d9Ly1CU1KkxTB6ZaOw/dO+CYSfVtqxVJccy832e6+7rW/dvSw5Jy7rsNhgcKSKjZq86LtNkPSvritOLA==}
 
@@ -938,6 +961,10 @@ packages:
     resolution: {integrity: sha512-wgm9Ehl2jpeqP3zw/7mo3kRHFp5MEDhqAdwy1fTGkHAwnkGOVsgpvQhL8B5n1qlb01jV3n/bI0ZfZp5lWA1k4w==}
     engines: {node: '>=18.0.0'}
 
+  '@istanbuljs/schema@0.1.3':
+    resolution: {integrity: sha512-ZXRY4jNvVgSVQ8DL3LTcakaAtXwTVUxE81hslsyD2AtoXW/wVob10HkOJ1X/pAlcI7D+2YoZKg5do8G/w6RYgA==}
+    engines: {node: '>=8'}
+
   '@jest/types@27.5.1':
     resolution: {integrity: sha512-Cx46iJ9QpwQTjIdq5VJu2QTMMs3QlEjI0x1QbBP5W1+nMzyc2XmimiRR/CbX9TO0cPTeUlxWMOu8mslYsJ8DEw==}
     engines: {node: ^10.13.0 || ^12.13.0 || ^14.15.0 || >=15.0.0}
@@ -1360,8 +1387,8 @@ packages:
   '@redocly/config@0.22.1':
     resolution: {integrity: sha512-1CqQfiG456v9ZgYBG9xRQHnpXjt8WoSnDwdkX6gxktuK69v2037hTAR1eh0DGIqpZ1p4k82cGH8yTNwt7/pI9g==}
 
-  '@redocly/openapi-core@1.33.0':
+  '@redocly/openapi-core@1.34.0':
-    resolution: {integrity: sha512-MUB1jPxYX2NmgiobICcvyrkSbPSaGAb/P/MsxSW+UT9hxpQvDCX81bstGg68BcKIdeFvVRKcoyG4xiTgDOEBfQ==}
+    resolution: {integrity: sha512-Ji00EiLQRXq0pJIz5pAjGF9MfQvQVsQehc6uIis6sqat8tG/zh25Zi64w6HVGEDgJEzUeq/CuUlD0emu3Hdaqw==}
     engines: {node: '>=18.17.0', npm: '>=9.5.0'}
 
   '@rollup/plugin-alias@5.1.1':
@@ -1774,6 +1801,15 @@ packages:
     engines: {node: '>=18'}
     hasBin: true
 
+  '@vitest/coverage-v8@3.0.8':
+    resolution: {integrity: sha512-y7SAKsQirsEJ2F8bulBck4DoluhI2EEgTimHd6EEUgJBGKy9tC25cpywh1MH4FvDGoG2Unt7+asVd1kj4qOSAw==}
+    peerDependencies:
+      '@vitest/browser': 3.0.8
+      vitest: 3.0.8
+    peerDependenciesMeta:
+      '@vitest/browser':
+        optional: true
+
   '@vitest/expect@3.0.8':
     resolution: {integrity: sha512-Xu6TTIavTvSSS6LZaA3EebWFr6tsoXPetOWNMOlc7LO88QVVBwq2oQWBoDiLCN6YTvNYsGSjqOO8CAdjom5DCQ==}
 
@@ -3535,6 +3571,10 @@ packages:
     engines: {node: '>=0.4.7'}
     hasBin: true
 
+  happy-dom@17.4.4:
+    resolution: {integrity: sha512-/Pb0ctk3HTZ5xEL3BZ0hK1AqDSAUuRQitOmROPHhfUYEWpmTImwfD8vFDGADmMAX0JYgbcgxWoLFKtsWhcpuVA==}
+    engines: {node: '>=18.0.0'}
+
   has-flag@3.0.0:
     resolution: {integrity: sha512-sKJf1+ceQBr4SMkvQnBDNDtf4TXpVhVGateu0t918bl30FnbE2m4vNLX+VWe/dpjlb+HugGYzW7uQXH98HPEYw==}
     engines: {node: '>=4'}
@@ -3573,6 +3613,9 @@ packages:
     resolution: {integrity: sha512-tmjcyZkG/qADhcdC7UjAp8D7v7W2DOYFgaZ48fYMuayMQmVVUg8fntKmrjes/b40ef6yZ+qt1lB8kuEDfLC4zw==}
     engines: {node: '>=10.0.0'}
 
+  html-escaper@2.0.2:
+    resolution: {integrity: sha512-H2iMtd0I4Mt5eYiapRdIDjp+XzelXQ0tFE4JS7YFwFevXXMmOp9myNrUvCg0D6ws8iqkRPBfKHgbwig1SmlLfg==}
+
   http-cache-semantics@4.1.1:
     resolution: {integrity: sha512-er295DKPVsV82j5kw1Gjt+ADA/XYHsajl82cGNQG2eyoPkvgUhX+nDIyelzhIWbbsXP39EHcI6l5tYs2FYqYXQ==}
 
@@ -3695,6 +3738,10 @@ packages:
     resolution: {integrity: sha512-MWDKS3AS1bGCHLBA2VLImJz42f7bJh8wQsTGCzI3j519/CASStoDONUBVz2I/VID0MpiX3SGSnbOD2xUalbE5g==}
     engines: {node: '>=18'}
 
+  index-to-position@1.0.0:
+    resolution: {integrity: sha512-sCO7uaLVhRJ25vz1o8s9IFM3nVS4DkuQnyjMwiQPKvQuBYBDmb8H7zx8ki7nVh4HJQOdVWebyvLE0qt+clruxA==}
+    engines: {node: '>=18'}
+
   inflight@1.0.6:
     resolution: {integrity: sha512-k92I/b08q4wvFscXCLvqfsHCrjrF7yiXsQuIVvVE7N82W3+aqpzuUdBbfhWcy/FZR3/4IgflMgKLOsvPDrGCJA==}
     deprecated: This module is not supported, and leaks memory. Do not use it. Check out lru-cache if you want a good and tested way to coalesce async requests by a key value, which is much more comprehensive and powerful.
@@ -3935,6 +3982,22 @@ packages:
     resolution: {integrity: sha512-3YZcUUR2Wt1WsapF+S/WiA2WmlW0cWAoPccMqne7AxEBhCdFeTPjfv/Axb8V2gyCgY3nRw+ksZ3xSUX+R47iAg==}
     engines: {node: ^18.17 || >=20.6.1}
 
+  istanbul-lib-coverage@3.2.2:
+    resolution: {integrity: sha512-O8dpsF+r0WV/8MNRKfnmrtCWhuKjxrq2w+jpzBL5UZKTi2LeVWnWOmWRxFlesJONmc+wLAGvKQZEOanko0LFTg==}
+    engines: {node: '>=8'}
+
+  istanbul-lib-report@3.0.1:
+    resolution: {integrity: sha512-GCfE1mtsHGOELCU8e/Z7YWzpmybrx/+dSTfLrvY8qRmaY6zXTKWn6WQIjaAFw069icm6GVMNkgu0NzI4iPZUNw==}
+    engines: {node: '>=10'}
+
+  istanbul-lib-source-maps@5.0.6:
+    resolution: {integrity: sha512-yg2d+Em4KizZC5niWhQaIomgf5WlL4vOOjZ5xGCmF8SnPE/mDWWXgvRExdcpCgh9lLRRa1/fSYp2ymmbJ1pI+A==}
+    engines: {node: '>=10'}
+
+  istanbul-reports@3.1.7:
+    resolution: {integrity: sha512-BewmUXImeuRk2YY0PVbxgKAysvhRPUQE0h5QRM++nVWyubKGV0l8qQ5op8+B2DOmwSe63Jivj0BjkPQVf8fP5g==}
+    engines: {node: '>=8'}
+
   jackspeak@3.4.3:
     resolution: {integrity: sha512-OGlZQpz2yfahA/Rd1Y8Cd9SIEsqvXkLVoSw/cgwhnhFMDbsQFeZYoJJ7bIZBS9BcamUW96asq/npPWugM+RQBw==}
 
@@ -4855,6 +4918,10 @@ packages:
     resolution: {integrity: sha512-rum1bPifK5SSar35Z6EKZuYPJx85pkNaFrxBK3mwdfSJ1/WKbYrjoW/zTPSjRRamfmVX1ACBIdFAO0VRErW/EA==}
     engines: {node: '>=18'}
 
+  parse-json@8.2.0:
+    resolution: {integrity: sha512-eONBZy4hm2AgxjNFd8a4nyDJnzUAH0g34xSQAwWEVGCjdZ4ZL7dKZBfq267GWP/JaS9zW62Xs2FeAdDvpHHJGQ==}
+    engines: {node: '>=18'}
+
   parse-ms@3.0.0:
     resolution: {integrity: sha512-Tpb8Z7r7XbbtBTrM9UhpkzzaMrqA2VXMT3YChzYltwV3P3pM6t8wl7TvpMnSTosz1aQAdVib7kdoys7vYOPerw==}
     engines: {node: '>=12'}
@@ -5101,8 +5168,8 @@ packages:
     resolution: {integrity: sha512-YWWTjgABSKcvs/nWBi9PycY/JiPJqOD4JA6o9Sej2AtvSGarXxKC3OQSk4pAarbdQlKAh5D4FCQkJNkW+GAn3w==}
     engines: {node: '>=0.6'}
 
-  quansync@0.2.8:
+  quansync@0.2.10:
-    resolution: {integrity: sha512-4+saucphJMazjt7iOM27mbFCk+D9dd/zmgMDCzRZ8MEoBfYp7lAvoN38et/phRQF6wOPMy/OROBGgoWeSKyluA==}
+    resolution: {integrity: sha512-t41VRkMYbkHyCYmOvx/6URnN80H7k4X0lLdBMGsz+maAwrJQYB1djpV6vHrQIBE0WBSGqhtEHrK9U3DWWH8v7A==}
 
   queue-microtask@1.2.3:
     resolution: {integrity: sha512-NuaNSa6flKT5JaSYQzJok04JzTL1CA6aGhv5rfLW3PgqA+M2ChpZQnAC8h8i4ZFkBS8X5RqkDBHA7r4hej3K9A==}
@@ -5794,6 +5861,10 @@ packages:
     engines: {node: '>=10'}
     hasBin: true
 
+  test-exclude@7.0.1:
+    resolution: {integrity: sha512-pFYqmTw68LXVjeWJMST4+borgQP2AyMNbg1BpZh9LbyhUeNkeaPF9gzfPGUAnSMV3qPYdWUwDIjjCLiSDOl7vg==}
+    engines: {node: '>=18'}
+
   text-decoder@1.2.3:
     resolution: {integrity: sha512-3/o9z3X0X0fTupwsYvR03pJ/DjWuqqrfwBgTQzdWDiQSm9KitAyz/9WqsT2JQW7KV2m+bC2ol/zqpW37NHxLaA==}
 
@@ -6031,8 +6102,8 @@ packages:
     resolution: {integrity: sha512-4/u/j4FrCKdi17jaxuJA0jClGxB1AvU2hw/IuayPc4ay1XGaJs/rbb4v5WKwAjNifjmXK9PIFyuPiaK8azyR9w==}
     engines: {node: '>=14.0.0'}
 
-  unplugin@2.2.0:
+  unplugin@2.2.2:
-    resolution: {integrity: sha512-m1ekpSwuOT5hxkJeZGRxO7gXbXT3gF26NjQ7GdVHoLoF8/nopLcd/QfPigpCy7i51oFHiRJg/CyHhj4vs2+KGw==}
+    resolution: {integrity: sha512-Qp+iiD+qCRnUek+nDoYvtWX7tfnYyXsrOnJ452FRTgOyKmTM7TUJ3l+PLPJOOWPTUyKISKp4isC5JJPSXUjGgw==}
     engines: {node: '>=18.12.0'}
 
   unstorage@1.15.0:
@@ -6252,9 +6323,17 @@ packages:
   webidl-conversions@3.0.1:
     resolution: {integrity: sha512-2JAn3z8AR6rjK8Sm8orRC0h/bcl/DqL7tRPdGZ4I1CjdF+EaMLmYxBHyXuKL849eucPFhvBoxMsflfOb8kxaeQ==}
 
+  webidl-conversions@7.0.0:
+    resolution: {integrity: sha512-VwddBukDzu71offAQR975unBIGqfKZpM+8ZX6ySk8nYhVoo5CYaZyzt3YBvYtRtO+aoGlqxPg/B87NGVZ/fu6g==}
+    engines: {node: '>=12'}
+
   webpack-virtual-modules@0.6.2:
     resolution: {integrity: sha512-66/V2i5hQanC51vBQKPH4aI8NMAcBW59FVBs+rC7eGHupMyfn34q7rZIE+ETlJ+XTevqfUhVVBgSUNSW2flEUQ==}
 
+  whatwg-mimetype@3.0.0:
+    resolution: {integrity: sha512-nt+N2dzIutVRxARx1nghPKGv1xHikU7HKdfafKkLNLindmPU/ch3U31NOCGGA/dmPcmb1VlofO0vnKAcsm0o/Q==}
+    engines: {node: '>=12'}
+
   whatwg-url@5.0.0:
     resolution: {integrity: sha512-saE57nupxk6v3HY35+jzBwYa0rKSy0XR8JSxZPwgLr7ys0IBzhGviA1/TUGJLmSVqs8pb9AnvICXEuOHLprYTw==}
 
@@ -6442,6 +6521,11 @@ packages:
 
 snapshots:
 
+  '@ampproject/remapping@2.3.0':
+    dependencies:
+      '@jridgewell/gen-mapping': 0.3.8
+      '@jridgewell/trace-mapping': 0.3.25
+
   '@babel/code-frame@7.26.2':
     dependencies:
       '@babel/helper-validator-identifier': 7.25.9
@@ -6452,15 +6536,26 @@ snapshots:
 
   '@babel/helper-validator-identifier@7.25.9': {}
 
+  '@babel/parser@7.26.10':
+    dependencies:
+      '@babel/types': 7.26.10
+
   '@babel/parser@7.26.9':
     dependencies:
       '@babel/types': 7.26.9
 
+  '@babel/types@7.26.10':
+    dependencies:
+      '@babel/helper-string-parser': 7.25.9
+      '@babel/helper-validator-identifier': 7.25.9
+
   '@babel/types@7.26.9':
     dependencies:
       '@babel/helper-string-parser': 7.25.9
       '@babel/helper-validator-identifier': 7.25.9
 
+  '@bcoe/v8-coverage@1.0.2': {}
+
   '@bugsnag/browser@7.25.0':
     dependencies:
       '@bugsnag/core': 7.25.0
@@ -7063,6 +7158,8 @@ snapshots:
     dependencies:
       minipass: 7.1.2
 
+  '@istanbuljs/schema@0.1.3': {}
+
   '@jest/types@27.5.1':
     dependencies:
       '@types/istanbul-lib-coverage': 2.0.6
@@ -7685,7 +7782,7 @@ snapshots:
 
   '@redocly/config@0.22.1': {}
 
-  '@redocly/openapi-core@1.33.0(supports-color@9.4.0)':
+  '@redocly/openapi-core@1.34.0(supports-color@9.4.0)':
     dependencies:
       '@redocly/ajv': 8.11.2
       '@redocly/config': 0.22.1
@@ -8035,6 +8132,24 @@ snapshots:
       - rollup
       - supports-color
 
+  '@vitest/coverage-v8@3.0.8(vitest@3.0.8(@types/node@22.13.10)(happy-dom@17.4.4)(jiti@2.4.2)(terser@5.39.0)(yaml@2.7.0))':
+    dependencies:
+      '@ampproject/remapping': 2.3.0
+      '@bcoe/v8-coverage': 1.0.2
+      debug: 4.4.0(supports-color@9.4.0)
+      istanbul-lib-coverage: 3.2.2
+      istanbul-lib-report: 3.0.1
+      istanbul-lib-source-maps: 5.0.6
+      istanbul-reports: 3.1.7
+      magic-string: 0.30.17
+      magicast: 0.3.5
+      std-env: 3.8.1
+      test-exclude: 7.0.1
+      tinyrainbow: 2.0.0
+      vitest: 3.0.8(@types/node@22.13.10)(happy-dom@17.4.4)(jiti@2.4.2)(terser@5.39.0)(yaml@2.7.0)
+    transitivePeerDependencies:
+      - supports-color
+
   '@vitest/expect@3.0.8':
     dependencies:
       '@vitest/spy': 3.0.8
@@ -10057,6 +10172,11 @@ snapshots:
     optionalDependencies:
       uglify-js: 2.8.29
 
+  happy-dom@17.4.4:
+    dependencies:
+      webidl-conversions: 7.0.0
+      whatwg-mimetype: 3.0.0
+
   has-flag@3.0.0: {}
 
   has-flag@4.0.0: {}
@@ -10085,6 +10205,8 @@ snapshots:
     optionalDependencies:
       unix-dgram: 2.0.6
 
+  html-escaper@2.0.2: {}
+
   http-cache-semantics@4.1.1: {}
 
   http-errors@1.6.2:
@@ -10206,6 +10328,8 @@ snapshots:
 
   index-to-position@0.1.2: {}
 
+  index-to-position@1.0.0: {}
+
   inflight@1.0.6:
     dependencies:
       once: 1.4.0
@@ -10451,6 +10575,27 @@ snapshots:
       lodash.isstring: 4.0.1
       lodash.uniqby: 4.7.0
 
+  istanbul-lib-coverage@3.2.2: {}
+
+  istanbul-lib-report@3.0.1:
+    dependencies:
+      istanbul-lib-coverage: 3.2.2
+      make-dir: 4.0.0
+      supports-color: 7.2.0
+
+  istanbul-lib-source-maps@5.0.6:
+    dependencies:
+      '@jridgewell/trace-mapping': 0.3.25
+      debug: 4.4.0(supports-color@9.4.0)
+      istanbul-lib-coverage: 3.2.2
+    transitivePeerDependencies:
+      - supports-color
+
+  istanbul-reports@3.1.7:
+    dependencies:
+      html-escaper: 2.0.2
+      istanbul-lib-report: 3.0.1
+
   jackspeak@3.4.3:
     dependencies:
       '@isaacs/cliui': 8.0.2
@@ -10620,7 +10765,7 @@ snapshots:
     dependencies:
       mlly: 1.7.4
       pkg-types: 2.1.0
-      quansync: 0.2.8
+      quansync: 0.2.10
 
   locate-path@6.0.0:
     dependencies:
@@ -10736,8 +10881,8 @@ snapshots:
 
   magicast@0.3.5:
     dependencies:
-      '@babel/parser': 7.26.9
+      '@babel/parser': 7.26.10
-      '@babel/types': 7.26.9
+      '@babel/types': 7.26.10
       source-map-js: 1.2.1
 
   make-dir@3.1.0:
@@ -11231,7 +11376,7 @@ snapshots:
 
   node-source-walk@6.0.2:
     dependencies:
-      '@babel/parser': 7.26.9
+      '@babel/parser': 7.26.10
 
   node-stream-zip@1.15.0: {}
 
@@ -11297,7 +11442,7 @@ snapshots:
   nypm@0.3.12:
     dependencies:
       citty: 0.1.6
-      consola: 3.4.0
+      consola: 3.4.2
       execa: 8.0.1
       pathe: 1.1.2
       pkg-types: 1.3.1
@@ -11374,10 +11519,10 @@ snapshots:
 
   openapi-typescript@7.6.1(typescript@5.8.2):
     dependencies:
-      '@redocly/openapi-core': 1.33.0(supports-color@9.4.0)
+      '@redocly/openapi-core': 1.34.0(supports-color@9.4.0)
       ansi-colors: 4.1.3
       change-case: 5.4.4
-      parse-json: 8.1.0
+      parse-json: 8.2.0
       supports-color: 9.4.0
       typescript: 5.8.2
       yargs-parser: 21.1.1
@@ -11580,6 +11725,12 @@ snapshots:
       index-to-position: 0.1.2
       type-fest: 4.37.0
 
+  parse-json@8.2.0:
+    dependencies:
+      '@babel/code-frame': 7.26.2
+      index-to-position: 1.0.0
+      type-fest: 4.37.0
+
   parse-ms@3.0.0: {}
 
   parse-ms@4.0.0: {}
@@ -11824,7 +11975,7 @@ snapshots:
     dependencies:
       side-channel: 1.1.0
 
-  quansync@0.2.8: {}
+  quansync@0.2.10: {}
 
   queue-microtask@1.2.3: {}
 
@@ -12655,6 +12806,12 @@ snapshots:
       commander: 2.20.3
       source-map-support: 0.5.21
 
+  test-exclude@7.0.1:
+    dependencies:
+      '@istanbuljs/schema': 0.1.3
+      glob: 10.4.5
+      minimatch: 9.0.5
+
   text-decoder@1.2.3:
     dependencies:
       b4a: 1.6.7
@@ -12817,7 +12974,7 @@ snapshots:
       acorn: 8.14.1
       estree-walker: 3.0.3
       magic-string: 0.30.17
-      unplugin: 2.2.0
+      unplugin: 2.2.2
 
   undici-types@6.20.0: {}
 
@@ -12857,7 +13014,7 @@ snapshots:
       scule: 1.3.0
       strip-literal: 3.0.0
       tinyglobby: 0.2.12
-      unplugin: 2.2.0
+      unplugin: 2.2.2
       unplugin-utils: 0.2.4
 
   unique-string@3.0.0:
@@ -12890,7 +13047,7 @@ snapshots:
       acorn: 8.14.1
       webpack-virtual-modules: 0.6.2
 
-  unplugin@2.2.0:
+  unplugin@2.2.2:
     dependencies:
       acorn: 8.14.1
       webpack-virtual-modules: 0.6.2
@@ -13019,7 +13176,7 @@ snapshots:
       terser: 5.39.0
       yaml: 2.7.0
 
-  vitest@3.0.8(@types/node@22.13.10)(jiti@2.4.2)(terser@5.39.0)(yaml@2.7.0):
+  vitest@3.0.8(@types/node@22.13.10)(happy-dom@17.4.4)(jiti@2.4.2)(terser@5.39.0)(yaml@2.7.0):
     dependencies:
       '@vitest/expect': 3.0.8
       '@vitest/mocker': 3.0.8(vite@6.2.1(@types/node@22.13.10)(jiti@2.4.2)(terser@5.39.0)(yaml@2.7.0))
@@ -13043,6 +13200,7 @@ snapshots:
       why-is-node-running: 2.3.0
     optionalDependencies:
       '@types/node': 22.13.10
+      happy-dom: 17.4.4
     transitivePeerDependencies:
       - jiti
       - less
@@ -13075,8 +13233,12 @@ snapshots:
 
   webidl-conversions@3.0.1: {}
 
+  webidl-conversions@7.0.0: {}
+
   webpack-virtual-modules@0.6.2: {}
 
+  whatwg-mimetype@3.0.0: {}
+
   whatwg-url@5.0.0:
     dependencies:
       tr46: 0.0.3

src/WebComponent.test.mjs

@@ -0,0 +1,25 @@
+import { beforeEach, describe, expect, it } from 'vitest'
+import { WebComponent } from './WebComponent.js'
+
+let componentUnderTest
+
+describe('WebComponent', () => {
+  // Browsers throw an error when you instantiate a custom element class not in the registry
+  window.customElements.define('component-test', WebComponent)
+
+  beforeEach(() => {
+    componentUnderTest = new WebComponent()
+  })
+
+  it('is instantiated', () => {
+    expect(componentUnderTest).toBeDefined()
+  })
+
+  it('has a readonly template prop', () => {
+    expect(componentUnderTest.template).toBe('')
+    const assignToReadonly = () => {
+      componentUnderTest.template = 'should error'
+    }
+    expect(() => assignToReadonly()).toThrowError()
+  })
+})

src/utils/serialize.test.mjs

@@ -0,0 +1,27 @@
+import { describe, expect, test } from 'vitest'
+import { serialize } from './serialize.mjs'
+
+describe('serialize', () => {
+  test('should stringify number', () => {
+    const result = serialize(3)
+    expect(result).toBeTypeOf('string')
+    expect(result).toEqual('3')
+  })
+
+  test('should stringify boolean', () => {
+    const result = serialize(false)
+    expect(result).toBeTypeOf('string')
+    expect(result).toEqual('false')
+  })
+
+  test('should stringify object', () => {
+    const result = serialize({ hello: 'world' })
+    expect(result).toBeTypeOf('string')
+    expect(result).toEqual('{"hello":"world"}')
+  })
+
+  test('should return undefined', () => {
+    const result = serialize(undefined)
+    expect(result).toBeUndefined()
+  })
+})

vitest.config.mjs

@@ -0,0 +1,13 @@
+import { defineConfig } from 'vitest/config'
+
+export default defineConfig({
+  test: {
+    environment: 'happy-dom',
+    coverage: {
+      enabled: true,
+      provider: 'v8',
+      reporter: ['html', 'text'],
+      include: ['src'],
+    },
+  },
+})