fix: #25 check for proper order with prefer-flat-map

Author: freaktechnik

package-lock.json

@@ -7,15 +7,15 @@
 module.exports = {
     meta: {
         docs: {
-            description: "Prefer using the flatMap over an immediate .map() call after a .flat().",
+            description: "Prefer using the flatMap over an immediate .flat() call after a .map().",
             recommended: true
         },
         fixable: "code",
         schema: []
     },
     create(context) {
         return {
-            'CallExpression[callee.type="MemberExpression"] > MemberExpression[property.name="map"] > CallExpression[callee.type="MemberExpression"][callee.property.name="flat"]'(node) {
+            'CallExpression[callee.type="MemberExpression"] > MemberExpression[property.name="flat"] > CallExpression[callee.type="MemberExpression"][callee.property.name="map"]'(node) {
                 const parent = node,
                     callee = node.parent;
                 node = callee.parent;
@@ -26,12 +26,18 @@ module.exports = {
                         start: parent.callee.property.loc.start,
                         end: callee.loc.end
                     },
-                    message: "Use flatMap instead of .flat().map()",
+                    message: "Use flatMap instead of .map().flat()",
                     fix(fixer) {
-                        return fixer.replaceTextRange([
-                            parent.callee.property.start,
-                            node.callee.property.end
-                        ], 'flatMap');
+                        return [
+                            fixer.replaceTextRange([
+                                parent.callee.property.start,
+                                parent.callee.property.end
+                            ], 'flatMap'),
+                            fixer.removeRange([
+                                callee.object.end,
+                                callee.parent.end
+                            ])
+                        ];
                     }
                 });
             }

rules/prefer-flat-map.js

@@ -13,16 +13,27 @@ ruleTester.run('prefer-flat-map', rule, {
         'array.flatMap((m) => m)',
         'array.flat()',
         'array.map((r) => r + 1)',
-        'array.map((r) => r + 1).flat()',
-        'array.flat().reverse().map((r) => r + 1)'
+        'array.flat().map((r) => r + 1)',
+        'array.map((r) => r + 1).reverse().flat()'
     ],
-    invalid: [ {
-        code: 'array.flat().map((p) => p)',
-        errors: [ {
-            message: 'Use flatMap instead of .flat().map()',
-            column: 7,
-            line: 1
-        } ],
-        output: 'array.flatMap((p) => p)'
-    } ]
+    invalid: [
+        {
+            code: 'array.map((p) => p).flat()',
+            errors: [ {
+                message: 'Use flatMap instead of .map().flat()',
+                column: 7,
+                line: 1
+            } ],
+            output: 'array.flatMap((p) => p)'
+        },
+        {
+            code: 'foo(); array.map((p) => p).flat(); test();',
+            errors: [ {
+                message: 'Use flatMap instead of .map().flat()',
+                column: 14,
+                line: 1
+            } ],
+            output: 'foo(); array.flatMap((p) => p); test();'
+        }
+    ]
 });