ignore environment markers in dep specs (#295)

Contributes to: #256

jest.config.js

@@ -0,0 +1,12 @@
+/** @type {import('ts-jest').JestConfigWithTsJest} */
+module.exports = {
+  collectCoverageFrom: ["src/**/*.ts", "!src/**/*.d.ts"],
+  moduleFileExtensions: ["ts", "js"],
+  preset: "ts-jest",
+  roots: ["<rootDir>/src"],
+  testEnvironment: "node",
+  testMatch: ["**/*.test.ts"],
+  transform: {
+    "^.+\\.ts$": "ts-jest",
+  },
+};