feat(oxfmt): Support TOML(v1.0 only) files

Cargo.toml

@@ -233,6 +233,13 @@ tracing-subscriber = "0.3.22" # Tracing implementation
 ureq = { version = "3.1.4", default-features = false } # HTTP client
 url = { version = "2.5.7" } # URL parsing
 walkdir = "2.5.0" # Directory traversal
+editorconfig-parser = "0.0.3"
+natord = "1.0.9"
+oxfmt = { path = "apps/oxfmt" }
+sort-package-json = "0.0.5"
+oxc-toml = "0.14.1"
+unicode-width = "0.2"
+website_common = { path = "tasks/website_common" }
 
 [workspace.metadata.cargo-shear]
 ignored = ["oxc_transform_napi", "oxc_parser_napi", "oxc_minify_napi"]

apps/oxfmt/Cargo.toml

@@ -37,15 +37,16 @@ oxc_span = { workspace = true }
 
 bpaf = { workspace = true, features = ["autocomplete", "bright-color", "derive"] }
 cow-utils = { workspace = true }
-editorconfig-parser = "0.0.3"
+editorconfig-parser = { workspace = true }
 ignore = { workspace = true, features = ["simd-accel"] }
 json-strip-comments = { workspace = true }
 miette = { workspace = true }
 phf = { workspace = true, features = ["macros"] }
 rayon = { workspace = true }
 serde_json = { workspace = true }
 simdutf8 = { workspace = true }
-sort-package-json = "0.0.5"
+sort-package-json = { workspace = true }
+oxc-toml = { workspace = true }
 tokio = { workspace = true, features = ["rt-multi-thread", "io-std", "macros"] }
 tracing = { workspace = true }
 tracing-subscriber = { workspace = true, features = [] } # Omit the `regex` feature

apps/oxfmt/src/core/config.rs

@@ -4,6 +4,7 @@ use editorconfig_parser::{
     EditorConfig, EditorConfigProperties, EditorConfigProperty, EndOfLine, IndentStyle,
     MaxLineLength,
 };
+use oxc_toml::formatter::Options as TomlFormatterOptions;
 use serde_json::Value;
 
 use oxc_formatter::{
@@ -53,6 +54,8 @@ pub enum ResolvedOptions {
         /// For embedded language formatting (e.g., CSS in template literals)
         external_options: Value,
     },
+    /// For TOML files.
+    OxfmtToml { toml_options: TomlFormatterOptions },
     /// For non-JS files formatted by external formatter (Prettier).
     #[cfg(feature = "napi")]
     ExternalFormatter { external_options: Value },
@@ -189,6 +192,9 @@ impl ConfigResolver {
             FormatFileStrategy::OxcFormatter { .. } => {
                 ResolvedOptions::OxcFormatter { format_options, external_options }
             }
+            FormatFileStrategy::OxfmtToml { .. } => {
+                ResolvedOptions::OxfmtToml { toml_options: build_toml_options(&format_options) }
+            }
             #[cfg(feature = "napi")]
             FormatFileStrategy::ExternalFormatter { .. } => {
                 ResolvedOptions::ExternalFormatter { external_options }
@@ -319,3 +325,23 @@ fn apply_editorconfig(oxfmtrc: &mut Oxfmtrc, props: &EditorConfigProperties) {
         oxfmtrc.tab_width = Some(size as u8);
     }
 }
+
+// ---
+
+/// Build `toml` formatter options.
+/// The same as `prettier-plugin-toml`.
+/// <https://github.com/un-ts/prettier/blob/7a4346d5dbf6b63987c0f81228fc46bb12f8692f/packages/toml/src/index.ts#L27-L31>
+fn build_toml_options(format_options: &FormatOptions) -> TomlFormatterOptions {
+    TomlFormatterOptions {
+        column_width: format_options.line_width.value() as usize,
+        indent_string: if format_options.indent_style.is_tab() {
+            "\t".to_string()
+        } else {
+            " ".repeat(format_options.indent_width.value() as usize)
+        },
+        trailing_newline: true,
+        array_trailing_comma: !format_options.trailing_commas.is_none(),
+        crlf: format_options.line_ending.is_carriage_return_line_feed(),
+        ..Default::default()
+    }
+}

apps/oxfmt/src/core/format.rs

@@ -59,6 +59,9 @@ impl SourceFormatter {
                 format_options,
                 external_options,
             ),
+            (FormatFileStrategy::OxfmtToml { .. }, ResolvedOptions::OxfmtToml { toml_options }) => {
+                Ok(Self::format_by_toml(source_text, toml_options))
+            }
             #[cfg(feature = "napi")]
             (
                 FormatFileStrategy::ExternalFormatter { path, parser_name },
@@ -149,6 +152,11 @@ impl SourceFormatter {
         Ok(code.into_code())
     }
 
+    /// Format TOML file using `toml`.
+    fn format_by_toml(source_text: &str, options: &oxc_toml::formatter::Options) -> String {
+        oxc_toml::formatter::format(source_text, options.clone())
+    }
+
     /// Format non-JS/TS file using external formatter (Prettier).
     #[cfg(feature = "napi")]
     fn format_by_external_formatter(

apps/oxfmt/src/core/support.rs

@@ -10,6 +10,10 @@ pub enum FormatFileStrategy {
         path: PathBuf,
         source_type: SourceType,
     },
+    /// TOML files formatted by taplo (Pure Rust).
+    OxfmtToml {
+        path: PathBuf,
+    },
     ExternalFormatter {
         path: PathBuf,
         #[cfg_attr(not(feature = "napi"), expect(dead_code))]
@@ -43,6 +47,11 @@ impl TryFrom<PathBuf> for FormatFileStrategy {
             return Err(());
         }
 
+        // Then TOML files
+        if is_toml_file(file_name) {
+            return Ok(Self::OxfmtToml { path });
+        }
+
         // Then external formatter files
         // `package.json` is special: sorted then formatted
         if file_name == "package.json" {
@@ -61,12 +70,13 @@ impl TryFrom<PathBuf> for FormatFileStrategy {
 impl FormatFileStrategy {
     #[cfg(not(feature = "napi"))]
     pub fn can_format_without_external(&self) -> bool {
-        matches!(self, Self::OxcFormatter { .. })
+        matches!(self, Self::OxcFormatter { .. } | Self::OxfmtToml { .. })
     }
 
     pub fn path(&self) -> &Path {
         match self {
             Self::OxcFormatter { path, .. }
+            | Self::OxfmtToml { path }
             | Self::ExternalFormatter { path, .. }
             | Self::ExternalFormatterPackageJson { path, .. } => path,
         }
@@ -86,16 +96,43 @@ static EXCLUDE_FILENAMES: phf::Set<&'static str> = phf_set! {
     "Pipfile.lock",
     "flake.lock",
     "mcmod.info",
+    // TOML lock files
+    "Cargo.lock",
+    "Gopkg.lock",
+    "pdm.lock",
+    "poetry.lock",
+    "uv.lock",
+};
+
+// ---
+
+/// Returns `true` if this is a TOML file.
+fn is_toml_file(file_name: &str) -> bool {
+    if TOML_FILENAMES.contains(file_name) {
+        return true;
+    }
+
+    #[expect(clippy::case_sensitive_file_extension_comparisons)]
+    if file_name.ends_with(".toml.example") || file_name.ends_with(".toml") {
+        return true;
+    }
+
+    false
+}
+
+static TOML_FILENAMES: phf::Set<&'static str> = phf_set! {
+    "Pipfile",
+    "Cargo.toml.orig",
 };
 
 // ---
 
 /// Returns parser name for external formatter, if supported.
-/// NOTE: `package.json` is handled separately in `TryFrom`.
 /// See also `prettier --support-info | jq '.languages[]'`
 fn get_external_parser_name(file_name: &str, extension: Option<&str>) -> Option<&'static str> {
     // JSON and variants
-    if JSON_STRINGIFY_FILENAMES.contains(file_name) || extension == Some("importmap") {
+    // NOTE: `package.json` is handled separately in `FormatFileStrategy::try_from()`
+    if file_name == "composer.json" || extension == Some("importmap") {
         return Some("json-stringify");
     }
     if JSON_FILENAMES.contains(file_name) {
@@ -185,11 +222,6 @@ fn get_external_parser_name(file_name: &str, extension: Option<&str>) -> Option<
     None
 }
 
-static JSON_STRINGIFY_FILENAMES: phf::Set<&'static str> = phf_set! {
-    // NOTE: `package.json` is handled separately as `ExternalFormatterPackageJson`
-    "composer.json",
-};
-
 static JSON_EXTENSIONS: phf::Set<&'static str> = phf_set! {
     "json",
     "4DForm",
@@ -399,4 +431,33 @@ mod tests {
         let source = FormatFileStrategy::try_from(PathBuf::from("composer.json")).unwrap();
         assert!(matches!(source, FormatFileStrategy::ExternalFormatter { .. }));
     }
+
+    #[test]
+    fn test_toml_files() {
+        // Files that should be detected as TOML
+        let toml_files = vec![
+            "Cargo.toml",
+            "pyproject.toml",
+            "config.toml",
+            "config.toml.example",
+            "Pipfile",
+            "Cargo.toml.orig",
+        ];
+
+        for file_name in toml_files {
+            let result = FormatFileStrategy::try_from(PathBuf::from(file_name));
+            assert!(
+                matches!(result, Ok(FormatFileStrategy::OxfmtToml { .. })),
+                "`{file_name}` should be detected as TOML"
+            );
+        }
+
+        // Lock files that should be excluded
+        let excluded_files = vec!["Cargo.lock", "poetry.lock", "pdm.lock", "uv.lock", "Gopkg.lock"];
+
+        for file_name in excluded_files {
+            let result = FormatFileStrategy::try_from(PathBuf::from(file_name));
+            assert!(result.is_err(), "`{file_name}` should be excluded (lock file)");
+        }
+    }
 }

crates/oxc_formatter/Cargo.toml

@@ -29,13 +29,13 @@ oxc_span = { workspace = true }
 oxc_syntax = { workspace = true }
 
 cow-utils = { workspace = true }
-natord = "1.0.9"
+natord = { workspace = true }
 phf = { workspace = true, features = ["macros"] }
 rustc-hash = { workspace = true }
 schemars = { workspace = true }
 serde = { workspace = true, features = ["derive"] }
 serde_json = { workspace = true }
-unicode-width = "0.2"
+unicode-width = { workspace = true }
 
 [dev-dependencies]
 insta = { workspace = true }

tasks/website_formatter/Cargo.toml

@@ -14,12 +14,12 @@ doctest = false
 
 [dependencies]
 bpaf = { workspace = true, features = ["docgen"] }
-oxc_formatter = { path = "../../crates/oxc_formatter" }
-oxfmt = { path = "../../apps/oxfmt" }
+oxc_formatter = { workspace = true }
+oxfmt = { workspace = true }
 pico-args = { workspace = true }
 schemars = { workspace = true }
 serde_json = { workspace = true }
-website_common = { path = "../website_common" }
+website_common = { workspace = true }
 
 [dev-dependencies]
 insta = { workspace = true }

tasks/website_linter/Cargo.toml

@@ -16,11 +16,11 @@ doctest = false
 bpaf = { workspace = true, features = ["docgen"] }
 itertools = { workspace = true }
 oxc_linter = { workspace = true, features = ["ruledocs"] }
-oxlint = { path = "../../apps/oxlint", default-features = false }
+oxlint = { workspace = true }
 pico-args = { workspace = true }
 project-root = { workspace = true }
 schemars = { workspace = true }
-website_common = { path = "../website_common" }
+website_common = { workspace = true }
 
 [dev-dependencies]
 insta = { workspace = true }