fix: --no-ignore should not apply to non-global ignores

lib/config/flat-config-array.js

@@ -18,6 +18,11 @@ const { defaultConfig } = require("./default-config");
 // Helpers
 //-----------------------------------------------------------------------------
 
+/**
+ * Fields that are considered metadata and not part of the config object.
+ */
+const META_FIELDS = new Set(["name"]);
+
 const ruleValidator = new RuleValidator();
 
 /**
@@ -135,15 +140,15 @@ class FlatConfigArray extends ConfigArray {
     [ConfigArraySymbol.preprocessConfig](config) {
 
         /*
-         * If `shouldIgnore` is false, we remove any ignore patterns specified
-         * in the config so long as it's not a default config and it doesn't
-         * have a `files` entry.
+         * If a config object has `ignores` and no other non-meta fields, then it's an object
+         * for global ignores. If `shouldIgnore` is false, that object shouldn't apply,
+         * so we'll remove its `ignores`.
          */
         if (
             !this.shouldIgnore &&
             !this[originalBaseConfig].includes(config) &&
             config.ignores &&
-            !config.files
+            Object.keys(config).filter(key => !META_FIELDS.has(key)).length === 1
         ) {
             /* eslint-disable-next-line no-unused-vars -- need to strip off other keys */
             const { ignores, ...otherKeys } = config;

tests/fixtures/eslint.config-with-ignores3.js

@@ -0,0 +1,9 @@
+const eslintConfig = require("./eslint.config.js");
+
+module.exports = [
+    eslintConfig,
+    {
+        name: "Global ignores",
+        ignores: ["**/*.json", "**/*.js"]
+    }
+];

tests/lib/eslint/eslint.js

@@ -1630,6 +1630,16 @@ describe("ESLint", () => {
                 }, /All files matched by 'tests\/fixtures\/cli-engine\/' are ignored\./u);
             });
 
+            it("should throw an error when all given files are ignored by a config object that has `name`", async () => {
+                eslint = new ESLint({
+                    overrideConfigFile: getFixturePath("eslint.config-with-ignores3.js")
+                });
+
+                await assert.rejects(async () => {
+                    await eslint.lintFiles(["tests/fixtures/cli-engine/"]);
+                }, /All files matched by 'tests\/fixtures\/cli-engine\/' are ignored\./u);
+            });
+
             it("should throw an error when all given files are ignored even with a `./` prefix", async () => {
                 eslint = new ESLint({
                     overrideConfigFile: getFixturePath("eslint.config-with-ignores.js")
@@ -1775,6 +1785,29 @@ describe("ESLint", () => {
                 assert.strictEqual(results[0].suppressedMessages.length, 0);
             });
 
+            it("should return two messages when given a file in excluded files list by a config object that has `name` while ignore is off", async () => {
+                eslint = new ESLint({
+                    cwd: getFixturePath(),
+                    ignore: false,
+                    overrideConfigFile: getFixturePath("eslint.config-with-ignores3.js"),
+                    overrideConfig: {
+                        rules: {
+                            "no-undef": 2
+                        }
+                    }
+                });
+                const filePath = fs.realpathSync(getFixturePath("undef.js"));
+                const results = await eslint.lintFiles([filePath]);
+
+                assert.strictEqual(results.length, 1);
+                assert.strictEqual(results[0].filePath, filePath);
+                assert.strictEqual(results[0].messages[0].ruleId, "no-undef");
+                assert.strictEqual(results[0].messages[0].severity, 2);
+                assert.strictEqual(results[0].messages[1].ruleId, "no-undef");
+                assert.strictEqual(results[0].messages[1].severity, 2);
+                assert.strictEqual(results[0].suppressedMessages.length, 0);
+            });
+
             // https://github.com/eslint/eslint/issues/16300
             it("should process ignore patterns relative to basePath not cwd", async () => {
                 eslint = new ESLint({
@@ -5698,6 +5731,30 @@ describe("ESLint", () => {
                 assert.strictEqual(warnResult.messages[0].ruleId, "no-unused-vars");
                 assert.strictEqual(warnResult.messages[0].severity, 1);
             });
+
+            // https://github.com/eslint/eslint/issues/18261
+            it("should apply to all files except for 'error.js' even with `ignore: false` option", async () => {
+                const engine = new ESLint({
+                    cwd,
+                    ignore: false
+                });
+
+                const results = await engine.lintFiles("{error,warn}.js");
+
+                assert.strictEqual(results.length, 2);
+
+                const [errorResult, warnResult] = results;
+
+                assert.strictEqual(errorResult.filePath, path.join(getPath(), "error.js"));
+                assert.strictEqual(errorResult.messages.length, 1);
+                assert.strictEqual(errorResult.messages[0].ruleId, "no-unused-vars");
+                assert.strictEqual(errorResult.messages[0].severity, 2);
+
+                assert.strictEqual(warnResult.filePath, path.join(getPath(), "warn.js"));
+                assert.strictEqual(warnResult.messages.length, 1);
+                assert.strictEqual(warnResult.messages[0].ruleId, "no-unused-vars");
+                assert.strictEqual(warnResult.messages[0].severity, 1);
+            });
         });
 
         describe("config with ignores: ['**/*.json']", () => {