diff --git a/src/cli/format.js b/src/cli/format.js
index 8d718c0c9..935dd82e3 100644
--- a/src/cli/format.js
+++ b/src/cli/format.js
@@ -18,6 +18,8 @@ function diff(a, b) {
   return createTwoFilesPatch("", "", a, b, "", "", { context: 2 });
 }
 
+class DebugError extends Error {}
+
 function handleError(context, filename, error, printedFilename) {
   if (error instanceof errors.UndefinedParserError) {
     // Can't test on CI, `isTTY()` is always false, see ./is-tty.js
@@ -52,7 +54,7 @@ function handleError(context, filename, error, printedFilename) {
     context.logger.error(error.message);
     // If validation fails for one file, it will fail for all of them.
     process.exit(1);
-  } else if (error instanceof errors.DebugError) {
+  } else if (error instanceof DebugError) {
     // `invalid.js: Some debug error message`
     context.logger.error(`${filename}: ${error.message}`);
   } else {
@@ -132,7 +134,7 @@ async function format(context, input, opt) {
     const pp = await prettier.format(input, opt);
     const pppp = await prettier.format(pp, opt);
     if (pp !== pppp) {
-      throw new errors.DebugError(
+      throw new DebugError(
         "prettier(input) !== prettier(prettier(input))\n" + diff(pp, pppp)
       );
     } else {
@@ -151,7 +153,7 @@ async function format(context, input, opt) {
           ast.length > MAX_AST_SIZE || past.length > MAX_AST_SIZE
             ? "AST diff too large to render"
             : diff(ast, past);
-        throw new errors.DebugError(
+        throw new DebugError(
           "ast(input) !== ast(prettier(input))\n" +
             astDiff +
             "\n" +
diff --git a/src/common/errors.js b/src/common/errors.js
index bc060690f..6107f8931 100644
--- a/src/common/errors.js
+++ b/src/common/errors.js
@@ -1,6 +1,5 @@
 class ConfigError extends Error {}
-class DebugError extends Error {}
 class UndefinedParserError extends Error {}
 class ArgExpansionBailout extends Error {}
 
-export { ConfigError, DebugError, UndefinedParserError, ArgExpansionBailout };
+export { ConfigError, UndefinedParserError, ArgExpansionBailout };