Tweak and re-organize ESLint config (#38369)

* Tweak and re-organize ESLint config

* merge individual configs to the root config
* enable more eslint-plugin-import rules
* lint markdown files

* Lint

.eslintrc.json

@@ -14,6 +14,35 @@
       "error",
       "never"
     ],
+    "import/extensions": [
+      "error",
+      "ignorePackages",
+      {
+        "js": "always"
+      }
+    ],
+    "import/first": "error",
+    "import/newline-after-import": "error",
+    "import/no-absolute-path": "error",
+    "import/no-amd": "error",
+    "import/no-cycle": [
+      "error",
+      {
+        "ignoreExternal": true
+      }
+    ],
+    "import/no-duplicates": "error",
+    "import/no-extraneous-dependencies": "error",
+    "import/no-mutable-exports": "error",
+    "import/no-named-as-default": "error",
+    "import/no-named-as-default-member": "error",
+    "import/no-named-default": "error",
+    "import/no-self-import": "error",
+    "import/no-unassigned-import": [
+      "error"
+    ],
+    "import/no-useless-path-segments": "error",
+    "import/order": "error",
     "indent": [
       "error",
       2,
@@ -51,7 +80,9 @@
       "error",
       "never"
     ],
+    "strict": "error",
     "unicorn/explicit-length-check": "off",
+    "unicorn/filename-case": "off",
     "unicorn/no-array-callback-reference": "off",
     "unicorn/no-array-method-this-argument": "off",
     "unicorn/no-null": "off",
@@ -63,5 +94,125 @@
     "unicorn/prefer-query-selector": "off",
     "unicorn/prefer-spread": "off",
     "unicorn/prevent-abbreviations": "off"
-  }
+  },
+  "overrides": [
+    {
+      "files": [
+        "build/**"
+      ],
+      "env": {
+        "browser": false,
+        "node": true
+      },
+      "parserOptions": {
+        "sourceType": "script"
+      },
+      "rules": {
+        "no-console": "off",
+        "unicorn/prefer-top-level-await": "off"
+      }
+    },
+    {
+      "files": [
+        "js/**"
+      ],
+      "parserOptions": {
+        "sourceType": "module"
+      }
+    },
+    {
+      "files": [
+        "js/tests/*.js",
+        "js/tests/integration/rollup*.js"
+      ],
+      "env": {
+        "node": true
+      },
+      "parserOptions": {
+        "sourceType": "script"
+      }
+    },
+    {
+      "files": [
+        "js/tests/unit/**"
+      ],
+      "env": {
+        "jasmine": true
+      },
+      "rules": {
+        "no-console": "off",
+        "unicorn/consistent-function-scoping": "off",
+        "unicorn/no-useless-undefined": "off",
+        "unicorn/prefer-add-event-listener": "off"
+      }
+    },
+    {
+      "files": [
+        "js/tests/visual/**"
+      ],
+      "plugins": [
+        "html"
+      ],
+      "settings": {
+        "html/html-extensions": [
+          ".html"
+        ]
+      },
+      "rules": {
+        "no-console": "off",
+        "no-new": "off",
+        "unicorn/no-array-for-each": "off"
+      }
+    },
+    {
+      "files": [
+        "scss/tests/**"
+      ],
+      "env": {
+        "node": true
+      },
+      "parserOptions": {
+        "sourceType": "script"
+      }
+    },
+    {
+      "files": [
+        "site/**"
+      ],
+      "env": {
+        "browser": true,
+        "node": false
+      },
+      "parserOptions": {
+        "sourceType": "script",
+        "ecmaVersion": 2019
+      },
+      "rules": {
+        "no-new": "off",
+        "unicorn/no-array-for-each": "off",
+        "unicorn/numeric-separators-style": "off"
+      }
+    },
+    {
+      "files": [
+        "**/*.md"
+      ],
+      "plugins": [
+        "markdown"
+      ],
+      "processor": "markdown/markdown"
+    },
+    {
+      "files": [
+        "**/*.md/*.js"
+      ],
+      "extends": "plugin:markdown/recommended",
+      "parserOptions": {
+        "sourceType": "module"
+      },
+      "rules": {
+        "unicorn/prefer-node-protocol": "off"
+      }
+    }
+  ]
 }