feat[coral]: no-restricted-imports for page components (#160)

- restrict page components to be only imported by router (except in test files)
- Introduce Ids to import restrict patterns. With Ids it
   will be easier to filter some specific pattern for a given
   file override.

Refers: #155

coral/.eslintrc.cjs

@@ -1,3 +1,47 @@
+const NO_RESTRICTED_IMPORTS_RULES = ["error", {
+    patterns: [{
+        id: "DENY_PAGES_IMPORT",
+        group: ["src/pages*"],
+        message: "Pages should be only imported from '/src/router.tsx'"
+    }]
+}]
+
+function isObject(value) {
+    return typeof value === 'object' &&
+    !Array.isArray(value) &&
+    value !== null
+}
+
+const hasPatterns = (value) => isObject(value) && "patterns" in value;
+const dropIdFromPatterns = (patterns) => patterns.map(({group, message}) => ({group, message}))
+
+function filterPatternsByIds(patterns, ids) {
+    return patterns.filter(pattern => {
+        if ("id" in pattern) {
+            return !ids.includes(pattern.id)
+        }
+        return true
+    })
+}
+
+function strip_ids_from_no_restricted_imports(configuration) {
+    return configuration.map((rule) => {
+        if (hasPatterns(rule)) {
+            return {...rule, patterns: dropIdFromPatterns(rule.patterns)}
+        }
+        return rule
+    })
+}
+
+function filter_patterns_for_ids(configuration, ids) {
+    return configuration.map(rule => {
+        if (hasPatterns(rule)) {
+            return {...rule, patterns: dropIdFromPatterns(filterPatternsByIds(rule.patterns, ids))}
+        }
+        return rule
+    })
+}
+
 module.exports = {
     "env": {
         "browser": true,
@@ -11,6 +55,12 @@ module.exports = {
         "prettier"
     ],
     "overrides": [
+        {
+            "files": ["src/router.tsx", "src/pages/**/*.test.tsx"],
+            "rules": {
+                "no-restricted-imports": filter_patterns_for_ids(NO_RESTRICTED_IMPORTS_RULES, ["DENY_PAGES_IMPORT"])
+            }
+        }
     ],
     "parser": "@typescript-eslint/parser",
     "parserOptions": {
@@ -30,6 +80,7 @@ module.exports = {
     "rules": {
         "no-relative-import-paths/no-relative-import-paths": [
             "error"
-        ]
+        ],
+        "no-restricted-imports": strip_ids_from_no_restricted_imports(NO_RESTRICTED_IMPORTS_RULES)
     }
 }