Fix printing ignored files with --debug-check (#4066)

src/cli/util.js

@@ -339,7 +339,9 @@ function formatFiles(context) {
     const fileIgnored = ignorer.filter([filename]).length === 0;
     if (
       fileIgnored &&
-      (context.argv["write"] || context.argv["list-different"])
+      (context.argv["debug-check"] ||
+        context.argv["write"] ||
+        context.argv["list-different"])
     ) {
       return;
     }

tests_integration/__tests__/__snapshots__/ignore-path.js.snap

@@ -1,5 +1,14 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
+exports[`ignore file when using --debug-check (stderr) 1`] = `""`;
+
+exports[`ignore file when using --debug-check (stdout) 1`] = `
+"other-regular-modules.js
+"
+`;
+
+exports[`ignore file when using --debug-check (write) 1`] = `Array []`;
+
 exports[`ignore path (stderr) 1`] = `""`;
 
 exports[`ignore path (stdout) 1`] = `

tests_integration/__tests__/ignore-path.js

@@ -19,6 +19,12 @@ describe("support .prettierignore", () => {
   });
 });
 
+describe("ignore file when using --debug-check", () => {
+  runPrettier("cli/ignore-path", ["**/*.js", "--debug-check"]).test({
+    status: 0
+  });
+});
+
 describe("outputs files as-is if no --write", () => {
   runPrettier("cli/ignore-path", ["regular-module.js"]).test({
     status: 0