feat: no-implicit-globals supports exported block comment (#16343)

Sosuke Suzuki · web-flow · commit 28d190264017 · 2022-10-14T17:02:29.000+02:00
* feat: support `"exported"` block comments

test: add valid tests

test: add invalid tests

* docs: mention about `exported` comment

docs: add correct example

* chore: use `variable.eslintExported` directly

* docs: add `:::` to close correct example

* fix: fix `exported` comment for multiple variables

* fix: add more invalid tests for global variable leaks
diff --git a/docs/src/rules/no-implicit-globals.md b/docs/src/rules/no-implicit-globals.md
@@ -5,6 +5,7 @@ rule_type: suggestion
 related_rules:
 - no-undef
 - no-global-assign
+- no-unused-vars
 further_reading:
 - https://benalman.com/news/2010/11/immediately-invoked-function-expression/
 - https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Errors/Undeclared_var
@@ -255,6 +256,22 @@ window.MyGlobalFunction = (function() {
 
 :::
 
+### exported
+
+You can use `/* exported variableName */` block comments in the same way as in [`no-unused-vars`](./no-unused-vars). See the [`no-unused-vars` exported section](./no-unused-vars#exported) for details.
+
+Examples of **correct** code for `/* exported variableName */` operation:
+
+::: correct
+
+```js
+/* exported global_var */
+
+var global_var = 42;
+```
+
+:::
+
 ## When Not To Use It
 
 In the case of a browser script, if you want to be able to explicitly declare variables and functions in the global scope,
diff --git a/lib/linter/linter.js b/lib/linter/linter.js
@@ -213,6 +213,7 @@ function addDeclaredGlobals(globalScope, configGlobals, { exportedVariables, ena
 
         if (variable) {
             variable.eslintUsed = true;
+            variable.eslintExported = true;
         }
     });
 
diff --git a/lib/rules/no-implicit-globals.js b/lib/rules/no-implicit-globals.js
@@ -77,6 +77,11 @@ module.exports = {
                         return;
                     }
 
+                    // Variables exported by "exported" block comments
+                    if (variable.eslintExported) {
+                        return;
+                    }
+
                     variable.defs.forEach(def => {
                         const defNode = def.node;
 
diff --git a/tests/lib/rules/no-implicit-globals.js b/tests/lib/rules/no-implicit-globals.js

Original file line number	Diff line number	Diff line change
`@@ -213,6 +213,7 @@ function addDeclaredGlobals(globalScope, configGlobals, { exportedVariables, ena`
`213`	`213`
`214`	`214`	`if (variable) {`
`215`	`215`	`variable.eslintUsed = true;`
	`216`	`+ variable.eslintExported = true;`
`216`	`217`	`}`
`217`	`218`	`});`
`218`	`219`