src: allow empty --experimental-config-file

marco-ippolito · marco-ippolito · commit b79afcfa4e2b · 2026-04-15T11:36:52.000+01:00
diff --git a/doc/api/cli.md b/doc/api/cli.md
@@ -1015,7 +1015,7 @@ added:
 
 Enable experimental import support for `.node` addons.
 
-### `--experimental-config-file=config`
+### `--experimental-config-file=path`, `--experimental-config-file`
 
 <!-- YAML
 added:
@@ -1026,6 +1026,12 @@ added:
 > Stability: 1.0 - Early development
 
 If present, Node.js will look for a configuration file at the specified path.
+If the path is not specified, Node.js will look for a `node.config.json` file
+in the current working directory.
+To specify a custom path, use the `--experimental-config-file=path` form.
+The space-separated `--experimental-config-file path` form is not supported.
+The alias `--experimental-default-config-file` is equivalent to
+`--experimental-config-file` without an argument.
 Node.js will read the configuration file and apply the settings. The
 configuration file should be a JSON file with the following structure. `vX.Y.Z`
 in the `$schema` must be replaced with the version of Node.js you are using.
@@ -1132,9 +1138,10 @@ added:
 
 > Stability: 1.0 - Early development
 
-If the `--experimental-default-config-file` flag is present, Node.js will look for a
+This flag is an alias for `--experimental-config-file` without an argument.
+If present, Node.js will look for a
 `node.config.json` file in the current working directory and load it as a
-as configuration file.
+configuration file.
 
 ### `--experimental-eventsource`
 
diff --git a/doc/api/test.md b/doc/api/test.md
@@ -4531,7 +4531,7 @@ test.describe('my suite', (suite) => {
 [`suite()`]: #suitename-options-fn
 [`test()`]: #testname-options-fn
 [code coverage]: #collecting-code-coverage
-[configuration files]: cli.md#--experimental-config-fileconfig
+[configuration files]: cli.md#--experimental-config-filepath---experimental-config-file
 [describe options]: #describename-options-fn
 [it options]: #testname-options-fn
 [module customization hooks]: module.md#customization-hooks
diff --git a/doc/node.1 b/doc/node.1
@@ -602,8 +602,12 @@ It is possible to run code containing inline types unless the
 .It Fl -experimental-addon-modules
 Enable experimental import support for \fB.node\fR addons.
 .
-.It Fl -experimental-config-file Ns = Ns Ar config
+.It Fl -experimental-config-file= Ns Ar config , Fl -experimental-config-file , Fl -experimental-default-config-file
 If present, Node.js will look for a configuration file at the specified path.
+If the path is not specified, Node.js will look for a \fBnode.config.json\fR file
+in the current working directory.
+To specify a custom path, use the \fB--experimental-config-file=\fR\fBpath\fR form.
+The space-separated \fB--experimental-config-file path\fR form is not supported.
 Node.js will read the configuration file and apply the settings. The
 configuration file should be a JSON file with the following structure. \fBvX.Y.Z\fR
 in the \fB$schema\fR must be replaced with the version of Node.js you are using.
@@ -689,9 +693,10 @@ Node.js will not sanitize or perform validation on the user-provided configurati
 so \fBNEVER\fR use untrusted configuration files.
 .
 .It Fl -experimental-default-config-file
-If the \fB--experimental-default-config-file\fR flag is present, Node.js will look for a
+This flag is an alias for \fB--experimental-config-file\fR without an argument.
+If present, Node.js will look for a
 \fBnode.config.json\fR file in the current working directory and load it as a
-as configuration file.
+configuration file.
 .
 .It Fl -experimental-eventsource
 Enable exposition of EventSource Web API on the global scope.
diff --git a/lib/internal/main/watch_mode.js b/lib/internal/main/watch_mode.js
@@ -1,7 +1,6 @@
 'use strict';
 const {
   ArrayPrototypeForEach,
-  ArrayPrototypeIncludes,
   ArrayPrototypeJoin,
   ArrayPrototypeMap,
   ArrayPrototypePush,
@@ -67,11 +66,8 @@ for (let i = 0; i < process.execArgv.length; i++) {
     }
     continue;
   }
-  if (StringPrototypeStartsWith(arg, '--experimental-config-file')) {
-    if (!ArrayPrototypeIncludes(arg, '=')) {
-      // Skip the flag and the next argument (the config file path)
-      i++;
-    }
+  if (arg === '--experimental-config-file' ||
+      StringPrototypeStartsWith(arg, '--experimental-config-file=')) {
     continue;
   }
   if (arg === '--experimental-default-config-file') {
diff --git a/lib/internal/process/pre_execution.js b/lib/internal/process/pre_execution.js
@@ -387,8 +387,7 @@ function setupSQLite() {
 }
 
 function initializeConfigFileSupport() {
-  if (getOptionValue('--experimental-default-config-file') ||
-      getOptionValue('--experimental-config-file')) {
+  if (getOptionValue('--experimental-config-file')) {
     emitExperimentalWarning('--experimental-config-file');
   }
 }
diff --git a/lib/internal/test_runner/runner.js b/lib/internal/test_runner/runner.js
@@ -161,7 +161,11 @@ function createTestFileList(patterns, cwd) {
 
 function filterExecArgv(arg, i, arr) {
   return !ArrayPrototypeIncludes(kFilterArgs, arg) &&
-  !ArrayPrototypeSome(kFilterArgValues, (p) => arg === p || (i > 0 && arr[i - 1] === p) || StringPrototypeStartsWith(arg, `${p}=`));
+  !ArrayPrototypeSome(kFilterArgValues, (p) => {
+    return arg === p ||
+      StringPrototypeStartsWith(arg, `${p}=`) ||
+      (p !== '--experimental-config-file' && i > 0 && arr[i - 1] === p);
+  });
 }
 
 function getRunArgs(path, { forceExit,
diff --git a/src/node.cc b/src/node.cc
@@ -900,7 +900,7 @@ static ExitCode InitializeNodeWithArgsInternal(
   }
 
   std::string node_options_from_config;
-  if (auto path = per_process::config_reader.GetDataFromArgs(*argv)) {
+  if (auto path = per_process::config_reader.GetDataFromArgs(argv)) {
     switch (per_process::config_reader.ParseConfig(*path)) {
       case ParseResult::Valid:
         break;
diff --git a/src/node_config_file.cc b/src/node_config_file.cc
@@ -2,39 +2,50 @@
 #include "debug_utils-inl.h"
 #include "simdjson.h"
 
-#include <string>
-
 namespace node {
 
+constexpr std::string_view kConfigFileFlag = "--experimental-config-file";
+constexpr std::string_view kDefaultConfigFileFlag =
+    "--experimental-default-config-file";
+constexpr std::string_view kDefaultConfigFileName = "node.config.json";
+
+inline bool HasEqualsPrefix(std::string_view arg, std::string_view flag) {
+  return arg.size() > flag.size() && arg.starts_with(flag) &&
+         arg[flag.size()] == '=';
+}
+
 std::optional<std::string_view> ConfigReader::GetDataFromArgs(
-    const std::vector<std::string>& args) {
-  constexpr std::string_view flag_path = "--experimental-config-file";
-  constexpr std::string_view default_file =
-      "--experimental-default-config-file";
-
-  bool has_default_config_file = false;
-
-  for (auto it = args.begin(); it != args.end(); ++it) {
-    if (*it == flag_path) {
-      // Case: "--experimental-config-file foo"
-      if (auto next = std::next(it); next != args.end()) {
-        return *next;
+    std::vector<std::string>* args) {
+  std::optional<std::string_view> result;
+
+  for (size_t i = 0; i < args->size(); ++i) {
+    std::string& arg = (*args)[i];
+
+    if (arg == kConfigFileFlag) {
+      // --experimental-config-file
+      arg = std::string(kConfigFileFlag) + "=" +
+            std::string(kDefaultConfigFileName);
+      result = kDefaultConfigFileName;
+    } else if (HasEqualsPrefix(arg, kConfigFileFlag)) {
+      // --experimental-config-file=path
+      std::string_view path = std::string_view(arg).substr(
+          kConfigFileFlag.size() + 1);
+      if (!path.empty()) {
+        result = path;
       }
-    } else if (it->starts_with(flag_path)) {
-      // Case: "--experimental-config-file=foo"
-      if (it->size() > flag_path.size() && (*it)[flag_path.size()] == '=') {
-        return std::string_view(*it).substr(flag_path.size() + 1);
-      }
-    } else if (*it == default_file || it->starts_with(default_file)) {
-      has_default_config_file = true;
+    } else if (arg == kDefaultConfigFileFlag) {
+      // --experimental-default-config-file
+      arg = std::string(kConfigFileFlag) + "=" +
+            std::string(kDefaultConfigFileName);
+      result = kDefaultConfigFileName;
+    } else if (HasEqualsPrefix(arg, kDefaultConfigFileFlag)) {
+      // Force the main option parser to report that this alias does not accept
+      // an explicit argument.
+      arg = std::string(kConfigFileFlag) + "=";
     }
   }
 
-  if (has_default_config_file) {
-    return "node.config.json";
-  }
-
-  return std::nullopt;
+  return result;
 }
 
 ParseResult ConfigReader::ProcessOptionValue(
diff --git a/src/node_config_file.h b/src/node_config_file.h
@@ -30,7 +30,7 @@ class ConfigReader {
   ParseResult ParseConfig(const std::string_view& config_path);
 
   std::optional<std::string_view> GetDataFromArgs(
-      const std::vector<std::string>& args);
+      std::vector<std::string>* args);
 
   std::string GetNodeOptions();
   const std::vector<std::string>& GetNamespaceFlags() const;
diff --git a/src/node_options.cc b/src/node_options.cc
@@ -885,11 +885,10 @@ EnvironmentOptionsParser::EnvironmentOptionsParser() {
             &EnvironmentOptions::optional_env_file);
   Implies("--env-file-if-exists", "[has_env_file_string]");
   AddOption("--experimental-config-file",
-            "set config file from supplied file",
-            &EnvironmentOptions::experimental_config_file_path);
-  AddOption("--experimental-default-config-file",
-            "set config file from default config file",
-            &EnvironmentOptions::experimental_default_config_file);
+            "set config file path",
+            &EnvironmentOptions::experimental_config_file_path,
+            kDisallowedInEnvvar);
+  AddAlias("--experimental-default-config-file", "--experimental-config-file");
   AddOption("--test",
             "launch test runner on startup",
             &EnvironmentOptions::test_runner,
diff --git a/src/node_options.h b/src/node_options.h
@@ -271,7 +271,6 @@ class EnvironmentOptions : public Options {
   bool report_exclude_env = false;
   bool report_exclude_network = false;
   std::string experimental_config_file_path;
-  bool experimental_default_config_file = false;
 
   inline DebugOptions* get_debug_options() { return &debug_options_; }
   inline const DebugOptions& debug_options() const { return debug_options_; }
diff --git a/test/parallel/test-cli-node-options-docs.js b/test/parallel/test-cli-node-options-docs.js
@@ -122,5 +122,6 @@ for (const [, envVar, config] of nodeOptionsCC.matchAll(addOptionRE)) {
 
 // add alias handling
 manPagesOptions.delete('-trace-events-enabled');
+manPagesOptions.delete('-experimental-default-config-file');
 
 assert.strictEqual(manPagesOptions.size, 0, `Man page options not documented: ${[...manPagesOptions]}`);
diff --git a/test/parallel/test-cli-options-as-flags.js b/test/parallel/test-cli-options-as-flags.js
@@ -55,8 +55,7 @@ describe('getOptionsAsFlagsFromBinding', () => {
     const result = await spawnPromisified(process.execPath, [
       '--no-warnings',
       '--expose-internals',
-      '--experimental-config-file',
-      configFile,
+      `--experimental-config-file=${configFile}`,
       fixtureFile,
     ]);
 
@@ -75,8 +74,7 @@ describe('getOptionsAsFlagsFromBinding', () => {
       '--no-warnings',
       '--expose-internals',
       '--stack-trace-limit=512',
-      '--experimental-config-file',
-      configFile,
+      `--experimental-config-file=${configFile}`,
       fixtureFile,
     ]);
 
diff --git a/test/parallel/test-config-file.js b/test/parallel/test-config-file.js
diff --git a/test/parallel/test-permission-config-file.mjs b/test/parallel/test-permission-config-file.mjs
diff --git a/test/parallel/test-runner-cli.js b/test/parallel/test-runner-cli.js
diff --git a/test/parallel/test-runner-flag-propagation.js b/test/parallel/test-runner-flag-propagation.js
diff --git a/test/sequential/test-watch-mode.mjs b/test/sequential/test-watch-mode.mjs

Original file line number	Diff line number	Diff line change
`@@ -387,8 +387,7 @@ function setupSQLite() {`
`387`	`387`	`}`
`388`	`388`
`389`	`389`	`function initializeConfigFileSupport() {`
`390`		`- if (getOptionValue('--experimental-default-config-file') \|\|`
`391`		`- getOptionValue('--experimental-config-file')) {`
	`390`	`+ if (getOptionValue('--experimental-config-file')) {`
`392`	`391`	`emitExperimentalWarning('--experimental-config-file');`
`393`	`392`	`}`
`394`	`393`	`}`
Original file line number	Diff line number	Diff line change
`@@ -900,7 +900,7 @@ static ExitCode InitializeNodeWithArgsInternal(`
`900`	`900`	`}`
`901`	`901`
`902`	`902`	`std::string node_options_from_config;`
`903`		`- if (auto path = per_process::config_reader.GetDataFromArgs(*argv)) {`
	`903`	`+ if (auto path = per_process::config_reader.GetDataFromArgs(argv)) {`
`904`	`904`	`switch (per_process::config_reader.ParseConfig(*path)) {`
`905`	`905`	`case ParseResult::Valid:`
`906`	`906`	`break;`