text-encoding-identifier-case: Auto-fix encoding in `fs.{readFile,r…

…eadFileSync}()` (#1755)

docs/rules/text-encoding-identifier-case.md

@@ -4,12 +4,14 @@
 <!-- RULE_NOTICE -->
 ✅ *This rule is part of the [recommended](https://github.com/sindresorhus/eslint-plugin-unicorn#recommended-config) config.*
 
-💡 *This rule provides [suggestions](https://eslint.org/docs/developer-guide/working-with-rules#providing-suggestions).*
+🔧💡 *This rule is [auto-fixable](https://eslint.org/docs/user-guide/command-line-interface#fixing-problems) and provides [suggestions](https://eslint.org/docs/developer-guide/working-with-rules#providing-suggestions).*
 <!-- /RULE_NOTICE -->
 
 - Enforce `'utf8'` for [UTF-8](https://en.wikipedia.org/wiki/UTF-8) encoding.
 - Enforce `'ascii'` for [ASCII](https://en.wikipedia.org/wiki/ASCII) encoding.
 
+This rule only auto-fix encoding in `fs.readFile()` and `fs.readFileSync()`.
+
 ## Fail
 
 ```js

readme.md

@@ -150,7 +150,7 @@ Each rule has emojis denoting:
 | [require-post-message-target-origin](docs/rules/require-post-message-target-origin.md) | Enforce using the `targetOrigin` argument with `window.postMessage()`. |  |  | 💡 |
 | [string-content](docs/rules/string-content.md) | Enforce better string content. |  | 🔧 | 💡 |
 | [template-indent](docs/rules/template-indent.md) | Fix whitespace-insensitive template indentation. | ✅ | 🔧 |  |
-| [text-encoding-identifier-case](docs/rules/text-encoding-identifier-case.md) | Enforce consistent case for text encoding identifiers. | ✅ |  | 💡 |
+| [text-encoding-identifier-case](docs/rules/text-encoding-identifier-case.md) | Enforce consistent case for text encoding identifiers. | ✅ | 🔧 | 💡 |
 | [throw-new-error](docs/rules/throw-new-error.md) | Require `new` when throwing an error. | ✅ | 🔧 |  |
 <!-- /RULES_TABLE -->
 

rules/text-encoding-identifier-case.js

@@ -19,6 +19,19 @@ const getReplacement = encoding => {
 	}
 };
 
+// `fs.{readFile,readFileSync}()`
+const isFsReadFileEncoding = node =>
+	node.parent.type === 'CallExpression'
+	&& !node.parent.optional
+	&& node.parent.arguments[1] === node
+	&& node.parent.arguments[0]
+	&& node.parent.arguments[0].type !== 'SpreadElement'
+	&& node.parent.callee.type === 'MemberExpression'
+	&& !node.parent.callee.optional
+	&& !node.parent.callee.computed
+	&& node.parent.callee.property.type === 'Identifier'
+	&& (node.parent.callee.property.name === 'readFile' || node.parent.callee.property.name === 'readFileSync');
+
 /** @param {import('eslint').Rule.RuleContext} context */
 const create = () => ({
 	Literal(node) {
@@ -39,19 +52,29 @@ const create = () => ({
 			replacement,
 		};
 
-		return {
+		/** @param {import('eslint').Rule.RuleFixer} fixer */
+		const fix = fixer => replaceStringLiteral(fixer, node, replacement);
+
+		const problem = {
 			node,
 			messageId: MESSAGE_ID_ERROR,
 			data: messageData,
-			suggest: [
-				{
-					messageId: MESSAGE_ID_SUGGESTION,
-					data: messageData,
-					/** @param {import('eslint').Rule.RuleFixer} fixer */
-					fix: fixer => replaceStringLiteral(fixer, node, replacement),
-				},
-			],
 		};
+
+		if (isFsReadFileEncoding(node)) {
+			problem.fix = fix;
+			return problem;
+		}
+
+		problem.suggest = [
+			{
+				messageId: MESSAGE_ID_SUGGESTION,
+				data: messageData,
+				fix: fixer => replaceStringLiteral(fixer, node, replacement),
+			},
+		];
+
+		return problem;
 	},
 });
 
@@ -63,6 +86,7 @@ module.exports = {
 		docs: {
 			description: 'Enforce consistent case for text encoding identifiers.',
 		},
+		fixable: 'code',
 		hasSuggestions: true,
 		messages,
 	},

test/snapshots/text-encoding-identifier-case.mjs.md

@@ -75,15 +75,207 @@ Generated by [AVA](https://avajs.dev).
     `
 
 ## Invalid #6
-      1 | await fs.readFile(file, "UTF-8",)
+      1 | fs.readFile?.(file, "UTF-8")
 
 > Error 1/1
 
     `␊
-    > 1 | await fs.readFile(file, "UTF-8",)␊
-        |                         ^^^^^^^ Prefer \`utf8\` over \`UTF-8\`.␊
+    > 1 | fs.readFile?.(file, "UTF-8")␊
+        |                     ^^^^^^^ Prefer \`utf8\` over \`UTF-8\`.␊
     ␊
     --------------------------------------------------------------------------------␊
     Suggestion 1/1: Replace \`UTF-8\` with \`utf8\`.␊
+      1 | fs.readFile?.(file, "utf8")␊
+    `
+
+## Invalid #7
+      1 | fs?.readFile(file, "UTF-8")
+
+> Error 1/1
+
+    `␊
+    > 1 | fs?.readFile(file, "UTF-8")␊
+        |                    ^^^^^^^ Prefer \`utf8\` over \`UTF-8\`.␊
+    ␊
+    --------------------------------------------------------------------------------␊
+    Suggestion 1/1: Replace \`UTF-8\` with \`utf8\`.␊
+      1 | fs?.readFile(file, "utf8")␊
+    `
+
+## Invalid #8
+      1 | readFile(file, "UTF-8")
+
+> Error 1/1
+
+    `␊
+    > 1 | readFile(file, "UTF-8")␊
+        |                ^^^^^^^ Prefer \`utf8\` over \`UTF-8\`.␊
+    ␊
+    --------------------------------------------------------------------------------␊
+    Suggestion 1/1: Replace \`UTF-8\` with \`utf8\`.␊
+      1 | readFile(file, "utf8")␊
+    `
+
+## Invalid #9
+      1 | fs.readFile(...file, "UTF-8")
+
+> Error 1/1
+
+    `␊
+    > 1 | fs.readFile(...file, "UTF-8")␊
+        |                      ^^^^^^^ Prefer \`utf8\` over \`UTF-8\`.␊
+    ␊
+    --------------------------------------------------------------------------------␊
+    Suggestion 1/1: Replace \`UTF-8\` with \`utf8\`.␊
+      1 | fs.readFile(...file, "utf8")␊
+    `
+
+## Invalid #10
+      1 | new fs.readFile(file, "UTF-8")
+
+> Error 1/1
+
+    `␊
+    > 1 | new fs.readFile(file, "UTF-8")␊
+        |                       ^^^^^^^ Prefer \`utf8\` over \`UTF-8\`.␊
+    ␊
+    --------------------------------------------------------------------------------␊
+    Suggestion 1/1: Replace \`UTF-8\` with \`utf8\`.␊
+      1 | new fs.readFile(file, "utf8")␊
+    `
+
+## Invalid #11
+      1 | fs.readFile(file, {encoding: "UTF-8"})
+
+> Error 1/1
+
+    `␊
+    > 1 | fs.readFile(file, {encoding: "UTF-8"})␊
+        |                              ^^^^^^^ Prefer \`utf8\` over \`UTF-8\`.␊
+    ␊
+    --------------------------------------------------------------------------------␊
+    Suggestion 1/1: Replace \`UTF-8\` with \`utf8\`.␊
+      1 | fs.readFile(file, {encoding: "utf8"})␊
+    `
+
+## Invalid #12
+      1 | fs.readFile("UTF-8")
+
+> Error 1/1
+
+    `␊
+    > 1 | fs.readFile("UTF-8")␊
+        |             ^^^^^^^ Prefer \`utf8\` over \`UTF-8\`.␊
+    ␊
+    --------------------------------------------------------------------------------␊
+    Suggestion 1/1: Replace \`UTF-8\` with \`utf8\`.␊
+      1 | fs.readFile("utf8")␊
+    `
+
+## Invalid #13
+      1 | fs.readFile(file, "UTF-8", () => {})
+
+> Output
+
+    `␊
+      1 | fs.readFile(file, "utf8", () => {})␊
+    `
+
+> Error 1/1
+
+    `␊
+    > 1 | fs.readFile(file, "UTF-8", () => {})␊
+        |                   ^^^^^^^ Prefer \`utf8\` over \`UTF-8\`.␊
+    `
+
+## Invalid #14
+      1 | fs.readFileSync(file, "UTF-8")
+
+> Output
+
+    `␊
+      1 | fs.readFileSync(file, "utf8")␊
+    `
+
+> Error 1/1
+
+    `␊
+    > 1 | fs.readFileSync(file, "UTF-8")␊
+        |                       ^^^^^^^ Prefer \`utf8\` over \`UTF-8\`.␊
+    `
+
+## Invalid #15
+      1 | fs[readFile](file, "UTF-8")
+
+> Error 1/1
+
+    `␊
+    > 1 | fs[readFile](file, "UTF-8")␊
+        |                    ^^^^^^^ Prefer \`utf8\` over \`UTF-8\`.␊
+    ␊
+    --------------------------------------------------------------------------------␊
+    Suggestion 1/1: Replace \`UTF-8\` with \`utf8\`.␊
+      1 | fs[readFile](file, "utf8")␊
+    `
+
+## Invalid #16
+      1 | fs["readFile"](file, "UTF-8")
+
+> Error 1/1
+
+    `␊
+    > 1 | fs["readFile"](file, "UTF-8")␊
+        |                      ^^^^^^^ Prefer \`utf8\` over \`UTF-8\`.␊
+    ␊
+    --------------------------------------------------------------------------------␊
+    Suggestion 1/1: Replace \`UTF-8\` with \`utf8\`.␊
+      1 | fs["readFile"](file, "utf8")␊
+    `
+
+## Invalid #17
+      1 | await fs.readFile(file, "UTF-8",)
+
+> Output
+
+    `␊
       1 | await fs.readFile(file, "utf8",)␊
     `
+
+> Error 1/1
+
+    `␊
+    > 1 | await fs.readFile(file, "UTF-8",)␊
+        |                         ^^^^^^^ Prefer \`utf8\` over \`UTF-8\`.␊
+    `
+
+## Invalid #18
+      1 | fs.promises.readFile(file, "UTF-8",)
+
+> Output
+
+    `␊
+      1 | fs.promises.readFile(file, "utf8",)␊
+    `
+
+> Error 1/1
+
+    `␊
+    > 1 | fs.promises.readFile(file, "UTF-8",)␊
+        |                            ^^^^^^^ Prefer \`utf8\` over \`UTF-8\`.␊
+    `
+
+## Invalid #19
+      1 | whatever.readFile(file, "UTF-8",)
+
+> Output
+
+    `␊
+      1 | whatever.readFile(file, "utf8",)␊
+    `
+
+> Error 1/1
+
+    `␊
+    > 1 | whatever.readFile(file, "UTF-8",)␊
+        |                         ^^^^^^^ Prefer \`utf8\` over \`UTF-8\`.␊
+    `

test/text-encoding-identifier-case.mjs

@@ -19,6 +19,19 @@ test.snapshot({
 		'\'utf-8\'',
 		'"Utf8"',
 		'"ASCII"',
+		'fs.readFile?.(file, "UTF-8")',
+		'fs?.readFile(file, "UTF-8")',
+		'readFile(file, "UTF-8")',
+		'fs.readFile(...file, "UTF-8")',
+		'new fs.readFile(file, "UTF-8")',
+		'fs.readFile(file, {encoding: "UTF-8"})',
+		'fs.readFile("UTF-8")',
+		'fs.readFile(file, "UTF-8", () => {})',
+		'fs.readFileSync(file, "UTF-8")',
+		'fs[readFile](file, "UTF-8")',
+		'fs["readFile"](file, "UTF-8")',
 		'await fs.readFile(file, "UTF-8",)',
+		'fs.promises.readFile(file, "UTF-8",)',
+		'whatever.readFile(file, "UTF-8",)',
 	],
 });