feat(oxfmt): `oxfmt --init` by Boshen · Pull Request #16703 · oxc-project/oxc

Boshen · 2025-12-10T14:51:32Z

Copilot

Pull request overview

This PR implements the --init flag for oxfmt, allowing users to initialize a default configuration file (.oxfmtrc.jsonc) in their project. The implementation follows a similar pattern to oxlint's --init functionality, including automatic detection and inclusion of JSON schema references when available.

Key Changes

Added --init command-line flag that creates .oxfmtrc.jsonc with default configuration
New ConfigFileInitSucceeded and ConfigFileInitFailed result variants to handle initialization outcomes
Automatic $schema reference injection when node_modules/oxfmt/configuration_schema.json exists

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 6 comments.

File	Description
apps/oxfmt/src/cli/command.rs	Adds the `init` boolean flag to `BasicOptions` struct with `hide_usage` attribute
apps/oxfmt/src/cli/result.rs	Adds two new enum variants for config initialization success/failure states and maps them to appropriate exit codes
apps/oxfmt/src/cli/format.rs	Implements `handle_init` method to create default config file, includes early exit logic in `run` method, and adds comprehensive tests for both schema and non-schema scenarios

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Copilot · 2025-12-10T14:57:55Z

apps/oxfmt/src/cli/format.rs

+        let config_path = cwd.join(Self::DEFAULT_OXFMTRC);
+        match fs::write(&config_path, configuration) {
+            Ok(()) => {
+                let _ = writeln!(stdout, "Configuration file created");


The success message should include the filename that was created for better user feedback. For example: "Configuration file created at .oxfmtrc.jsonc". This is consistent with oxlint's implementation and provides clearer information to the user.

Suggested change

let _ = writeln!(stdout, "Configuration file created");

let _ = writeln!(stdout, "Configuration file created at {}", config_path.display());

Copilot · 2025-12-10T14:57:55Z

apps/oxfmt/src/cli/format.rs

+    #[test]
+    fn test_init_config() {
+        let temp_dir = env::temp_dir().join("oxfmt_init_test");
+        fs::create_dir_all(&temp_dir).unwrap();
+
+        let config_path = temp_dir.join(FormatRunner::DEFAULT_OXFMTRC);
+        let _ = fs::remove_file(&config_path);
+
+        let mut stdout = Vec::new();
+        let mut stderr = Vec::new();
+        let result = FormatRunner::handle_init(&temp_dir, &mut stdout, &mut stderr);
+
+        assert!(matches!(result, CliRunResult::ConfigFileInitSucceeded));
+        assert!(config_path.exists());
+
+        // Verify valid JSON
+        let content = fs::read_to_string(&config_path).unwrap();
+        let _: serde_json::Value = serde_json::from_str(&content).unwrap();
+
+        // Cleanup
+        fs::remove_file(&config_path).unwrap();
+        fs::remove_dir(&temp_dir).unwrap();
+    }


Missing test coverage for the case when a configuration file already exists. Consider adding a test that verifies the behavior when --init is run and .oxfmtrc.jsonc already exists (e.g., whether it overwrites, fails, or prompts).

Copilot · 2025-12-10T14:57:56Z

apps/oxfmt/src/cli/result.rs

+            Self::InvalidOptionConfig | Self::FormatMismatch | Self::ConfigFileInitFailed => {
+                ExitCode::from(1)
+            }
            Self::NoFilesFound | Self::FormatFailed => ExitCode::from(2),


ConfigFileInitFailed is categorized under "Fatal error" in the comment but returns exit code 1 (warning error) in the implementation. This is inconsistent. If it's truly a fatal error, it should return exit code 2 like other fatal errors (NoFilesFound, FormatFailed). Otherwise, the comment should categorize it as a warning error.

Suggested change

Self::InvalidOptionConfig | Self::FormatMismatch | Self::ConfigFileInitFailed => {

ExitCode::from(1)

}

Self::NoFilesFound | Self::FormatFailed => ExitCode::from(2),

Self::InvalidOptionConfig | Self::FormatMismatch => {

ExitCode::from(1)

}

Self::NoFilesFound | Self::FormatFailed | Self::ConfigFileInitFailed => ExitCode::from(2),

Copilot · 2025-12-10T14:57:56Z

apps/oxfmt/src/cli/format.rs

+            config_string
+        };
+
+        // Write to .oxfmtrc.json


The comment says "Write to .oxfmtrc.json" but the actual filename constant is .oxfmtrc.jsonc (with 'c' suffix). The comment should be updated to match the actual filename being used.

Suggested change

// Write to .oxfmtrc.json

// Write to .oxfmtrc.jsonc

Copilot · 2025-12-10T14:57:56Z

apps/oxfmt/src/cli/format.rs

+        // Write to .oxfmtrc.json
+        let config_path = cwd.join(Self::DEFAULT_OXFMTRC);
+        match fs::write(&config_path, configuration) {
+            Ok(()) => {
+                let _ = writeln!(stdout, "Configuration file created");
+                CliRunResult::ConfigFileInitSucceeded
+            }
+            Err(e) => {
+                let _ = writeln!(stderr, "Failed to create configuration file: {e}");
+                CliRunResult::ConfigFileInitFailed
+            }
+        }


The --init flag should check if the configuration file already exists before writing to prevent silently overwriting existing user configurations. Consider warning the user or failing gracefully if the file exists. Compare with common tools like npm init which prompts for confirmation or uses a --force flag for overwriting.

Copilot · 2025-12-10T14:57:56Z

apps/oxfmt/src/cli/format.rs

+            let mut config_json: Value = serde_json::from_str(&config_string).unwrap();
+            if let Value::Object(ref mut obj) = config_json {
+                let mut json_object = serde_json::Map::new();
+                json_object
+                    .insert("$schema".to_string(), format!("./{schema_relative_path}").into());
+                json_object.extend(obj.clone());
+                *obj = json_object;
+            }
+            serde_json::to_string_pretty(&config_json).unwrap()


The .unwrap() calls on lines 272 and 280 could panic if JSON serialization/deserialization fails unexpectedly. While unlikely since we just successfully serialized the config, it's safer to handle these errors explicitly and return CliRunResult::ConfigFileInitFailed with an appropriate error message to stderr.

graphite-app · 2025-12-10T15:01:35Z

apps/oxfmt/src/cli/format.rs

+        // Write to .oxfmtrc.json
+        let config_path = cwd.join(Self::DEFAULT_OXFMTRC);
+        match fs::write(&config_path, configuration) {
+            Ok(()) => {
+                let _ = writeln!(stdout, "Configuration file created");
+                CliRunResult::ConfigFileInitSucceeded
+            }
+            Err(e) => {
+                let _ = writeln!(stderr, "Failed to create configuration file: {e}");
+                CliRunResult::ConfigFileInitFailed
+            }
+        }


The code does not check if the configuration file already exists before writing to it. This will silently overwrite any existing .oxfmtrc.jsonc file, potentially causing data loss for users who already have a configuration.

// Check if config file already exists let config_path = cwd.join(Self::DEFAULT_OXFMTRC); if config_path.exists() { let _ = writeln!(stderr, "Configuration file already exists at {}", config_path.display()); return CliRunResult::ConfigFileInitFailed; } match fs::write(&config_path, configuration) { // ... }

Suggested change

// Write to .oxfmtrc.json

let config_path = cwd.join(Self::DEFAULT_OXFMTRC);

match fs::write(&config_path, configuration) {

Ok(()) => {

let _ = writeln!(stdout, "Configuration file created");

CliRunResult::ConfigFileInitSucceeded

}

Err(e) => {

let _ = writeln!(stderr, "Failed to create configuration file: {e}");

CliRunResult::ConfigFileInitFailed

}

}

// Write to .oxfmtrc.json

let config_path = cwd.join(Self::DEFAULT_OXFMTRC);

// Check if config file already exists

if config_path.exists() {

let _ = writeln!(stderr, "Configuration file already exists at {}", config_path.display());

return CliRunResult::ConfigFileInitFailed;

}

match fs::write(&config_path, configuration) {

Ok(()) => {

let _ = writeln!(stdout, "Configuration file created");

CliRunResult::ConfigFileInitSucceeded

}

Err(e) => {

let _ = writeln!(stderr, "Failed to create configuration file: {e}");

CliRunResult::ConfigFileInitFailed

}

}

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leaysgur · 2025-12-11T01:07:34Z

The TODO has been finalized #16622, so I'll close this PR and redo it.

Follow up #16703, fixes #16622 I will add test for `--init` and also `--lsp` later.

Boshen assigned leaysgur Dec 10, 2025

Copilot AI review requested due to automatic review settings December 10, 2025 14:51

github-actions bot added A-cli Area - CLI A-formatter Area - Formatter C-enhancement Category - New feature or request labels Dec 10, 2025

Copilot started reviewing on behalf of Boshen December 10, 2025 14:51 View session

feat(oxfmt): oxfmt --init

d692118

closes #16622

Boshen force-pushed the 12-10-feat_oxfmt_oxfmt_--init_ branch from 6d49dbd to d692118 Compare December 10, 2025 14:54

Copilot AI reviewed Dec 10, 2025

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graphite-app bot reviewed Dec 10, 2025

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leaysgur closed this Dec 11, 2025

leaysgur deleted the 12-10-feat_oxfmt_oxfmt_--init_ branch December 11, 2025 01:07

leaysgur mentioned this pull request Dec 11, 2025

feat(oxfmt): Support oxfmt --init #16720

Merged

graphite-app bot pushed a commit that referenced this pull request Dec 11, 2025

feat(oxfmt): Support oxfmt --init (#16720)

559eff1

Follow up #16703, fixes #16622 I will add test for `--init` and also `--lsp` later.

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feat(oxfmt): `oxfmt --init`#16703

feat(oxfmt): `oxfmt --init`#16703
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	let _ = writeln!(stdout, "Configuration file created");
	let _ = writeln!(stdout, "Configuration file created at {}", config_path.display());

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Pull request overview

Key Changes

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