feature: @putout/plugin-esm: apply-export-from: add

Author: coderaiser

packages/plugin-esm/README.md

@@ -18,6 +18,7 @@ npm i putout @putout/plugin-esm -D
 
 ## Rules
 
+- ✅ [apply-export-from](#apply-export-from);
 - ✅ [declare-imports-first](#declare-imports-first);
 - ✅ [group-imports-by-source](#group-imports-by-source);
 - ✅ [merge-duplicate-imports](#merge-duplicate-imports);
@@ -31,6 +32,7 @@ npm i putout @putout/plugin-esm -D
 ```json
 {
     "rules": {
+        "esm/apply-export-from": "on",
         "esm/declare-imports-first": "on",
         "esm/group-imports-by-source": "on",
         "esm/merge-duplicate-imports": "on",
@@ -44,6 +46,30 @@ npm i putout @putout/plugin-esm -D
 }
 ```
 
+## apply-export-from
+
+> The `export` declaration is used to export values from a JavaScript module.
+>
+> (c) [MDN](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/export)
+
+Check out in 🐊[**Putout Editor**](https://putout.cloudcmd.io/#/gist/c9a3983d269745da89c1c7560f3b7fac/3ecb9aa6b910ce3816605bae11c8dd86bdc457e5).
+
+## ❌ Example of incorrect code
+
+```js
+import * as ns_1 from 'x';
+
+export {
+    ns_1 as ns,
+};
+```
+
+## ✅ Example of correct code
+
+```js
+export * as ns from 'x';
+```
+
 ## declare-imports-first
 
 Check out in 🐊[**Putout Editor**](https://putout.cloudcmd.io/#/gist/b1c18e5d726afe4ebb69d6b7a7dda82b/8189590815a1b8adb35bb8a846e28228e3c7fadf). For **CommonJS** use [nodejs/declare-after-require](https://github.com/coderaiser/putout/tree/master/packages/plugin-nodejs#declare-after-require).

packages/plugin-esm/lib/apply-export-from/fixture/apply-export-from-fix.js

@@ -0,0 +1 @@
+export * as ns from 'x';

packages/plugin-esm/lib/apply-export-from/fixture/apply-export-from.js

@@ -0,0 +1,3 @@
+
+import * as ns_1 from "x";
+export { ns_1 as ns };

packages/plugin-esm/lib/apply-export-from/index.js

@@ -0,0 +1,45 @@
+'use strict';
+
+const {types, operator} = require('putout');
+
+const {
+    compare,
+    getTemplateValues,
+    remove,
+} = operator;
+
+const {ExportNamespaceSpecifier} = types;
+
+module.exports.report = () => `Use 'export *' instead of 'import/export'`;
+
+const IMPORT = 'import * as __a from "__b"';
+
+module.exports.fix = ({path, current}) => {
+    const {exported} = current.node.specifiers[0];
+    
+    current.node.source = path.node.source;
+    
+    delete current.node.local;
+    delete current.node.exported;
+    
+    current.node.specifiers = [
+        ExportNamespaceSpecifier(exported),
+    ];
+    
+    remove(path);
+};
+
+module.exports.traverse = ({push}) => ({
+    [IMPORT]: (path) => {
+        const {__a} = getTemplateValues(path, IMPORT);
+        const {name} = __a;
+        
+        for (const current of path.parentPath.get('body')) {
+            if (compare(current, `export {${name} as __b}`))
+                push({
+                    path,
+                    current,
+                });
+        }
+    },
+});

packages/plugin-esm/lib/apply-export-from/index.spec.js

@@ -0,0 +1,20 @@
+'use strict';
+
+const {createTest} = require('@putout/test');
+const plugin = require('.');
+
+const test = createTest(__dirname, {
+    plugins: [
+        ['apply-export-from', plugin],
+    ],
+});
+
+test('esm: apply-export-from: report', (t) => {
+    t.report('apply-export-from', `Use 'export *' instead of 'import/export'`);
+    t.end();
+});
+
+test('esm: apply-export-from: transform', (t) => {
+    t.transform('apply-export-from');
+    t.end();
+});

packages/plugin-esm/lib/index.js

@@ -8,6 +8,7 @@ const removeEmptyImport = require('./remove-empty-import');
 const removeEmptyExport = require('./remove-empty-export');
 const mergeDuplicateImports = require('./merge-duplicate-imports');
 const convertAssertToWith = require('./convert-assert-to-with');
+const applyExportFrom = require('./apply-export-from');
 
 module.exports.rules = {
     ...mergeDuplicateImports.rules,
@@ -18,4 +19,5 @@ module.exports.rules = {
     'remove-empty-export': removeEmptyExport,
     'sort-imports-by-specifiers': sortImportsBySpecifiers,
     'convert-assert-to-with': convertAssertToWith,
+    'apply-export-from': applyExportFrom,
 };

packages/plugin-esm/test/esm.js

@@ -48,3 +48,8 @@ test('putout: plugin: esm: merge-duplicate-imports: convert-assert-to-with: tran
     t.transform('convert-assert-to-with');
     t.end();
 });
+
+test('plugin-esm: transform: apply-export-from', (t) => {
+    t.transform('apply-export-from');
+    t.end();
+});

packages/plugin-esm/test/fixture/apply-export-from-fix.js

@@ -0,0 +1 @@
+export * as ns from 'x';

packages/plugin-esm/test/fixture/apply-export-from.js

@@ -0,0 +1,3 @@
+
+import * as ns_1 from "x";
+export { ns_1 as ns };