Fix edge case in prefer-math-min-max rule

Author: axetroy

rules/prefer-math-min-max.js

@@ -19,7 +19,21 @@ function reportPreferMathMinOrMax(context, node, left, right, method) {
 		data: {
 			replacement: `${method}()`,
 		},
-		fix: fixer => fixer.replaceText(node, `${method}(${sourceCode.getText(left)}, ${sourceCode.getText(right)})`),
+		* fix(fixer) {
+			/**
+			 * ```js
+			 * function a() {
+			 *   return+foo > 10 ? 10 : +foo
+			 * }
+			 * ```
+			 */
+			if (node.parent.type === 'ReturnStatement' && node.parent.argument === node && node.parent.start + 'return'.length === node.start) {
+				// If there is no space between ReturnStatement and ConditionalExpression, add a space.
+				yield fixer.insertTextBefore(node, ' ');
+			}
+
+			yield fixer.replaceText(node, `${method}(${sourceCode.getText(left)}, ${sourceCode.getText(right)})`);
+		},
 	});
 }
 
@@ -36,7 +50,7 @@ const create = context => ({
 		const {sourceCode} = context;
 		const {operator, left, right} = test;
 
-		const checkTypes = new Set(['Literal', 'Identifier', 'MemberExpression', 'CallExpression']);
+		const checkTypes = new Set(['Literal', 'Identifier', 'MemberExpression', 'CallExpression', 'UnaryExpression']);
 
 		if ([left, right, alternate, consequent].some(n => !checkTypes.has(n.type))) {
 			return;

test/prefer-math-min-max.mjs

@@ -1,3 +1,4 @@
+import {outdent} from 'outdent';
 import {getTester} from './utils/test.mjs';
 
 const {test} = getTester(import.meta);
@@ -32,5 +33,17 @@ test.snapshot({
 		// Prefer `Math.max()`
 		'height > maxHeight ? height : maxHeight',
 		'height < maxHeight ? maxHeight : height',
+
+		// Edge test when there is no space between ReturnStatement and ConditionalExpression
+		outdent`
+			function a() {
+				return +foo > 10 ? 10 : +foo
+			}
+		`,
+		outdent`
+			function a() {
+				return+foo > 10 ? 10 : +foo
+			}
+		`,
 	],
 });

test/snapshots/prefer-math-min-max.mjs.md

@@ -297,3 +297,57 @@ Generated by [AVA](https://avajs.dev).
     > 1 | height < maxHeight ? maxHeight : height␊
         | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Prefer \`Math.max()\` to simplify ternary expressions.␊
     `
+
+## invalid(15): function a() { return +foo > 10 ? 10 : +foo }
+
+> Input
+
+    `␊
+      1 | function a() {␊
+      2 | 	return +foo > 10 ? 10 : +foo␊
+      3 | }␊
+    `
+
+> Output
+
+    `␊
+      1 | function a() {␊
+      2 | 	return Math.min(+foo, 10)␊
+      3 | }␊
+    `
+
+> Error 1/1
+
+    `␊
+      1 | function a() {␊
+    > 2 | 	return +foo > 10 ? 10 : +foo␊
+        | 	       ^^^^^^^^^^^^^^^^^^^^^ Prefer \`Math.min()\` to simplify ternary expressions.␊
+      3 | }␊
+    `
+
+## invalid(16): function a() { return+foo > 10 ? 10 : +foo }
+
+> Input
+
+    `␊
+      1 | function a() {␊
+      2 | 	return+foo > 10 ? 10 : +foo␊
+      3 | }␊
+    `
+
+> Output
+
+    `␊
+      1 | function a() {␊
+      2 | 	return Math.min(+foo, 10)␊
+      3 | }␊
+    `
+
+> Error 1/1
+
+    `␊
+      1 | function a() {␊
+    > 2 | 	return+foo > 10 ? 10 : +foo␊
+        | 	      ^^^^^^^^^^^^^^^^^^^^^ Prefer \`Math.min()\` to simplify ternary expressions.␊
+      3 | }␊
+    `