feat: Add --no-warn-ignored CLI option for flat config (#17569)

* Add warnIgnored CLI option for flat config

* Update ignore result warning message about its suppression

* Add test for lintText warnIgnored overriding constructor option

* Respect constructor warnIgnored when linting via stdin

* Move warnIgnored help text under Miscellaneous

* Use void 0 instead of undefined

* Add test cases for eslint.lintFiles with warnIgnored:false

* Add assertion for error message when warnIgnored is not the right type

* Change file ignore warning wording

* Simplify error condition

* Fix accidentally commented out test line

* Add documentation for --no-warn-ignored CLI flag

* Clarify warnIgnored descriptions

docs/src/use/command-line-interface.md

@@ -110,6 +110,7 @@ Miscellaneous:
   --env-info                      Output execution environment information - default: false
   --no-error-on-unmatched-pattern  Prevent errors when pattern is unmatched
   --exit-on-fatal-error           Exit with exit code 2 in case of fatal error - default: false
+  --no-warn-ignored               Suppress warnings when the file list includes ignored files. *Flat Config Mode Only*
   --debug                         Output debugging information
   -h, --help                      Show help
   -v, --version                   Output the version number
@@ -703,6 +704,18 @@ This option causes ESLint to exit with exit code 2 if one or more fatal parsing
 npx eslint --exit-on-fatal-error file.js
 ```
 
+#### `--no-warn-ignored`
+
+**Flat Config Mode Only.** This option suppresses both `File ignored by default` and `File ignored because of a matching ignore pattern` warnings when an ignored filename is passed explicitly. It is useful when paired with `--max-warnings 0` as it will prevent exit code 1 due to the aforementioned warning.
+
+* **Argument Type**: No argument.
+
+##### `--no-warn-ignored` example
+
+```shell
+npx eslint --no-warn-ignored --max-warnings 0 ignored-file.js
+```
+
 #### `--debug`
 
 This option outputs debugging information to the console. Add this flag to an ESLint command line invocation in order to get extra debugging information while the command runs.

docs/src/use/configure/ignore.md

@@ -149,7 +149,7 @@ You'll see this warning:
 
 ```text
 foo.js
-  0:0  warning  File ignored because of a matching ignore pattern. Use "--no-ignore" to override.
+  0:0  warning  File ignored because of a matching ignore pattern. Use "--no-ignore" to disable file ignore settings or use "--no-warn-ignored" to suppress this warning.
 
 ✖ 1 problem (0 errors, 1 warning)
 ```

lib/cli.js

@@ -91,7 +91,8 @@ async function translateOptions({
     reportUnusedDisableDirectives,
     resolvePluginsRelativeTo,
     rule,
-    rulesdir
+    rulesdir,
+    warnIgnored
 }, configType) {
 
     let overrideConfig, overrideConfigFile;
@@ -182,6 +183,7 @@ async function translateOptions({
 
     if (configType === "flat") {
         options.ignorePatterns = ignorePattern;
+        options.warnIgnored = warnIgnored;
     } else {
         options.resolvePluginsRelativeTo = resolvePluginsRelativeTo;
         options.rulePaths = rulesdir;
@@ -385,7 +387,9 @@ const cli = {
         if (useStdin) {
             results = await engine.lintText(text, {
                 filePath: options.stdinFilename,
-                warnIgnored: true
+
+                // flatConfig respects CLI flag and constructor warnIgnored, eslintrc forces true for backwards compatibility
+                warnIgnored: usingFlatConfig ? void 0 : true
             });
         } else {
             results = await engine.lintFiles(files);

lib/eslint/eslint-helpers.js

@@ -594,9 +594,9 @@ function createIgnoreResult(filePath, baseDir) {
     const isInNodeModules = baseDir && path.dirname(path.relative(baseDir, filePath)).split(path.sep).includes("node_modules");
 
     if (isInNodeModules) {
-        message = "File ignored by default because it is located under the node_modules directory. Use ignore pattern \"!**/node_modules/\" to override.";
+        message = "File ignored by default because it is located under the node_modules directory. Use ignore pattern \"!**/node_modules/\" to disable file ignore settings or use \"--no-warn-ignored\" to suppress this warning.";
     } else {
-        message = "File ignored because of a matching ignore pattern. Use \"--no-ignore\" to override.";
+        message = "File ignored because of a matching ignore pattern. Use \"--no-ignore\" to disable file ignore settings or use \"--no-warn-ignored\" to suppress this warning.";
     }
 
     return {
@@ -676,6 +676,7 @@ function processOptions({
     overrideConfigFile = null,
     plugins = {},
     reportUnusedDisableDirectives = null, // ← should be null by default because if it's a string then it overrides the 'reportUnusedDisableDirectives' setting in config files. And we cannot use `overrideConfig.reportUnusedDisableDirectives` instead because we cannot configure the `error` severity with that.
+    warnIgnored = true,
     ...unknownOptions
 }) {
     const errors = [];
@@ -781,6 +782,9 @@ function processOptions({
     ) {
         errors.push("'reportUnusedDisableDirectives' must be any of \"error\", \"warn\", \"off\", and null.");
     }
+    if (typeof warnIgnored !== "boolean") {
+        errors.push("'warnIgnored' must be a boolean.");
+    }
     if (errors.length > 0) {
         throw new ESLintInvalidOptionsError(errors);
     }
@@ -802,7 +806,8 @@ function processOptions({
         globInputPaths,
         ignore,
         ignorePatterns,
-        reportUnusedDisableDirectives
+        reportUnusedDisableDirectives,
+        warnIgnored
     };
 }
 

lib/eslint/flat-eslint.js

@@ -84,6 +84,7 @@ const LintResultCache = require("../cli-engine/lint-result-cache");
  *      when a string.
  * @property {Record<string,Plugin>} [plugins] An array of plugin implementations.
  * @property {"error" | "warn" | "off"} [reportUnusedDisableDirectives] the severity to report unused eslint-disable directives.
+ * @property {boolean} warnIgnored Show warnings when the file list includes ignored files
  */
 
 //------------------------------------------------------------------------------
@@ -749,7 +750,8 @@ class FlatESLint {
             fixTypes,
             reportUnusedDisableDirectives,
             globInputPaths,
-            errorOnUnmatchedPattern
+            errorOnUnmatchedPattern,
+            warnIgnored
         } = eslintOptions;
         const startTime = Date.now();
         const fixTypesSet = fixTypes ? new Set(fixTypes) : null;
@@ -795,7 +797,11 @@ class FlatESLint {
                  * pattern, then notify the user.
                  */
                 if (ignored) {
-                    return createIgnoreResult(filePath, cwd);
+                    if (warnIgnored) {
+                        return createIgnoreResult(filePath, cwd);
+                    }
+
+                    return void 0;
                 }
 
                 const config = configs.getConfig(filePath);
@@ -908,7 +914,7 @@ class FlatESLint {
 
         const {
             filePath,
-            warnIgnored = false,
+            warnIgnored,
             ...unknownOptions
         } = options || {};
 
@@ -922,7 +928,7 @@ class FlatESLint {
             throw new Error("'options.filePath' must be a non-empty string or undefined");
         }
 
-        if (typeof warnIgnored !== "boolean") {
+        if (typeof warnIgnored !== "boolean" && typeof warnIgnored !== "undefined") {
             throw new Error("'options.warnIgnored' must be a boolean or undefined");
         }
 
@@ -937,15 +943,18 @@ class FlatESLint {
             allowInlineConfig,
             cwd,
             fix,
-            reportUnusedDisableDirectives
+            reportUnusedDisableDirectives,
+            warnIgnored: constructorWarnIgnored
         } = eslintOptions;
         const results = [];
         const startTime = Date.now();
         const resolvedFilename = path.resolve(cwd, filePath || "__placeholder__.js");
 
         // Clear the last used config arrays.
         if (resolvedFilename && await this.isPathIgnored(resolvedFilename)) {
-            if (warnIgnored) {
+            const shouldWarnIgnored = typeof warnIgnored === "boolean" ? warnIgnored : constructorWarnIgnored;
+
+            if (shouldWarnIgnored) {
                 results.push(createIgnoreResult(resolvedFilename, cwd));
             }
         } else {

lib/options.js

@@ -55,6 +55,7 @@ const optionator = require("optionator");
  * @property {string} [stdinFilename] Specify filename to process STDIN as
  * @property {boolean} quiet Report errors only
  * @property {boolean} [version] Output the version number
+ * @property {boolean} warnIgnored Show warnings when the file list includes ignored files
  * @property {string[]} _ Positional filenames or patterns
  */
 
@@ -139,6 +140,17 @@ module.exports = function(usingFlatConfig) {
         };
     }
 
+    let warnIgnoredFlag;
+
+    if (usingFlatConfig) {
+        warnIgnoredFlag = {
+            option: "warn-ignored",
+            type: "Boolean",
+            default: "true",
+            description: "Suppress warnings when the file list includes ignored files"
+        };
+    }
+
     return optionator({
         prepend: "eslint [options] file.js [file.js] [dir]",
         defaults: {
@@ -349,6 +361,7 @@ module.exports = function(usingFlatConfig) {
                 default: "false",
                 description: "Exit with exit code 2 in case of fatal error"
             },
+            warnIgnoredFlag,
             {
                 option: "debug",
                 type: "Boolean",

tests/lib/cli.js

@@ -801,6 +801,32 @@ describe("cli", () => {
                         assert.isFalse(log.info.called);
                         assert.strictEqual(exit, 0);
                     });
+
+                    it(`should suppress the warning if --no-warn-ignored is passed with configType:${configType}`, async () => {
+                        const options = useFlatConfig
+                            ? `--config ${getFixturePath("eslint.config_with_ignores.js")}`
+                            : `--ignore-path ${getFixturePath(".eslintignore")}`;
+                        const filePath = getFixturePath("passing.js");
+                        const exit = await cli.execute(`${options} --no-warn-ignored ${filePath}`, null, useFlatConfig);
+
+                        assert.isFalse(log.info.called);
+
+                        // When eslintrc is used, we get an exit code of 2 because the --no-warn-ignored option is unrecognized.
+                        assert.strictEqual(exit, useFlatConfig ? 0 : 2);
+                    });
+
+                    it(`should suppress the warning if --no-warn-ignored is passed and an ignored file is passed via stdin with configType:${configType}`, async () => {
+                        const options = useFlatConfig
+                            ? `--config ${getFixturePath("eslint.config_with_ignores.js")}`
+                            : `--ignore-path ${getFixturePath(".eslintignore")}`;
+                        const filePath = getFixturePath("passing.js");
+                        const exit = await cli.execute(`${options} --no-warn-ignored --stdin --stdin-filename ${filePath}`, "foo", useFlatConfig);
+
+                        assert.isFalse(log.info.called);
+
+                        // When eslintrc is used, we get an exit code of 2 because the --no-warn-ignored option is unrecognized.
+                        assert.strictEqual(exit, useFlatConfig ? 0 : 2);
+                    });
                 });
 
                 describe("when given a pattern to ignore", () => {