Narrow the supported options on the format CLI (#6944)

## Summary

Ensures that we only show supported options:

<img width="1228" alt="Screen Shot 2023-08-28 at 11 03 16 AM"
src="50fb7595-dc30-43d2-a7e4-c0103acc15b9">

For now, I'm not super focused on DRYing up the CLI.

crates/ruff_cli/src/args.rs

@@ -34,7 +34,7 @@ pub struct Args {
 #[derive(Debug, clap::Subcommand)]
 pub enum Command {
     /// Run Ruff on the given files or directories (default).
-    Check(CheckArgs),
+    Check(CheckCommand),
     /// Explain a rule (or all rules).
     #[clap(alias = "--explain")]
     #[command(group = clap::ArgGroup::new("selector").multiple(false).required(true))]
@@ -51,9 +51,9 @@ pub enum Command {
         #[arg(long, value_enum, default_value = "text")]
         format: HelpFormat,
     },
-    /// List or describe the available configuration options
+    /// List or describe the available configuration options.
     Config { option: Option<String> },
-    /// List all supported upstream linters
+    /// List all supported upstream linters.
     Linter {
         /// Output format
         #[arg(long, value_enum, default_value = "text")]
@@ -65,19 +65,16 @@ pub enum Command {
     /// Generate shell completion.
     #[clap(alias = "--generate-shell-completion", hide = true)]
     GenerateShellCompletion { shell: clap_complete_command::Shell },
-    /// Format the given files, or stdin when using `-`.
+    /// Run the Ruff formatter on the given files or directories.
     #[doc(hidden)]
     #[clap(hide = true)]
-    Format {
+    Format(FormatCommand),
-        /// List of files or directories to format or `-` for stdin
-        files: Vec<PathBuf>,
-    },
 }
 
 // The `Parser` derive is for ruff_dev, for ruff_cli `Args` would be sufficient
 #[derive(Clone, Debug, clap::Parser)]
-#[allow(clippy::struct_excessive_bools, clippy::module_name_repetitions)]
+#[allow(clippy::struct_excessive_bools)]
-pub struct CheckArgs {
+pub struct CheckCommand {
     /// List of files or directories to check.
     pub files: Vec<PathBuf>,
     /// Attempt to automatically fix lint violations.
@@ -95,15 +92,13 @@ pub struct CheckArgs {
     show_fixes: bool,
     #[clap(long, overrides_with("show_fixes"), hide = true)]
     no_show_fixes: bool,
-    /// Avoid writing any fixed files back; instead, output a diff for each
+    /// Avoid writing any fixed files back; instead, output a diff for each changed file to stdout. Implies `--fix-only`.
-    /// changed file to stdout. Implies `--fix-only`.
     #[arg(long, conflicts_with = "show_fixes")]
     pub diff: bool,
     /// Run in watch mode by re-running whenever files change.
     #[arg(short, long)]
     pub watch: bool,
-    /// Fix any fixable lint violations, but don't report on leftover
+    /// Fix any fixable lint violations, but don't report on leftover violations. Implies `--fix`.
-    /// violations. Implies `--fix`.
     #[arg(long, overrides_with("no_fix_only"))]
     fix_only: bool,
     #[clap(long, overrides_with("fix_only"), hide = true)]
@@ -124,8 +119,7 @@ pub struct CheckArgs {
     /// configuration.
     #[arg(long, conflicts_with = "isolated")]
     pub config: Option<PathBuf>,
-    /// Comma-separated list of rule codes to enable (or ALL, to enable all
+    /// Comma-separated list of rule codes to enable (or ALL, to enable all rules).
-    /// rules).
     #[arg(
         long,
         value_delimiter = ',',
@@ -145,8 +139,7 @@ pub struct CheckArgs {
         hide_possible_values = true
     )]
     pub ignore: Option<Vec<RuleSelector>>,
-    /// Like --select, but adds additional rule codes on top of those already
+    /// Like --select, but adds additional rule codes on top of those already specified.
-    /// specified.
     #[arg(
         long,
         value_delimiter = ',',
@@ -169,8 +162,7 @@ pub struct CheckArgs {
     /// List of mappings from file pattern to code to exclude.
     #[arg(long, value_delimiter = ',', help_heading = "Rule selection")]
     pub per_file_ignores: Option<Vec<PatternPrefixPair>>,
-    /// Like `--per-file-ignores`, but adds additional ignores on top of
+    /// Like `--per-file-ignores`, but adds additional ignores on top of those already specified.
-    /// those already specified.
     #[arg(long, value_delimiter = ',', help_heading = "Rule selection")]
     pub extend_per_file_ignores: Option<Vec<PatternPrefixPair>>,
     /// List of paths, used to omit files and/or directories from analysis.
@@ -181,8 +173,7 @@ pub struct CheckArgs {
         help_heading = "File selection"
     )]
     pub exclude: Option<Vec<FilePattern>>,
-    /// Like --exclude, but adds additional files and directories on top of
+    /// Like --exclude, but adds additional files and directories on top of those already excluded.
-    /// those already excluded.
     #[arg(
         long,
         value_delimiter = ',',
@@ -190,8 +181,7 @@ pub struct CheckArgs {
         help_heading = "File selection"
     )]
     pub extend_exclude: Option<Vec<FilePattern>>,
-    /// List of rule codes to treat as eligible for autofix. Only applicable
+    /// List of rule codes to treat as eligible for autofix. Only applicable when autofix itself is enabled (e.g., via `--fix`).
-    /// when autofix itself is enabled (e.g., via `--fix`).
     #[arg(
         long,
         value_delimiter = ',',
@@ -201,8 +191,7 @@ pub struct CheckArgs {
         hide_possible_values = true
     )]
     pub fixable: Option<Vec<RuleSelector>>,
-    /// List of rule codes to treat as ineligible for autofix. Only applicable
+    /// List of rule codes to treat as ineligible for autofix. Only applicable when autofix itself is enabled (e.g., via `--fix`).
-    /// when autofix itself is enabled (e.g., via `--fix`).
     #[arg(
         long,
         value_delimiter = ',',
@@ -212,8 +201,7 @@ pub struct CheckArgs {
         hide_possible_values = true
     )]
     pub unfixable: Option<Vec<RuleSelector>>,
-    /// Like --fixable, but adds additional rule codes on top of those already
+    /// Like --fixable, but adds additional rule codes on top of those already specified.
-    /// specified.
     #[arg(
         long,
         value_delimiter = ',',
@@ -233,8 +221,7 @@ pub struct CheckArgs {
         hide = true
     )]
     pub extend_unfixable: Option<Vec<RuleSelector>>,
-    /// Respect file exclusions via `.gitignore` and other standard ignore
+    /// Respect file exclusions via `.gitignore` and other standard ignore files.
-    /// files.
     #[arg(
         long,
         overrides_with("no_respect_gitignore"),
@@ -243,8 +230,7 @@ pub struct CheckArgs {
     respect_gitignore: bool,
     #[clap(long, overrides_with("respect_gitignore"), hide = true)]
     no_respect_gitignore: bool,
-    /// Enforce exclusions, even for paths passed to Ruff directly on the
+    /// Enforce exclusions, even for paths passed to Ruff directly on the command-line.
-    /// command-line.
     #[arg(
         long,
         overrides_with("no_force_exclude"),
@@ -253,8 +239,7 @@ pub struct CheckArgs {
     force_exclude: bool,
     #[clap(long, overrides_with("force_exclude"), hide = true)]
     no_force_exclude: bool,
-    /// Set the line-length for length-associated rules and automatic
+    /// Set the line-length for length-associated rules and automatic formatting.
-    /// formatting.
     #[arg(long, help_heading = "Rule configuration", hide = true)]
     pub line_length: Option<LineLength>,
     /// Regular expression matching the name of dummy variables.
@@ -280,8 +265,7 @@ pub struct CheckArgs {
         conflicts_with = "exit_non_zero_on_fix"
     )]
     pub exit_zero: bool,
-    /// Exit with a non-zero status code if any files were modified via
+    /// Exit with a non-zero status code if any files were modified via autofix, even if no lint violations remain.
-    /// autofix, even if no lint violations remain.
     #[arg(long, help_heading = "Miscellaneous", conflicts_with = "exit_zero")]
     pub exit_non_zero_on_fix: bool,
     /// Show counts for every rule with at least one violation.
@@ -340,6 +324,46 @@ pub struct CheckArgs {
     pub ecosystem_ci: bool,
 }
 
+#[derive(Clone, Debug, clap::Parser)]
+#[allow(clippy::struct_excessive_bools)]
+pub struct FormatCommand {
+    /// List of files or directories to format.
+    pub files: Vec<PathBuf>,
+    /// The minimum Python version that should be supported.
+    #[arg(long, value_enum)]
+    pub target_version: Option<PythonVersion>,
+    /// Path to the `pyproject.toml` or `ruff.toml` file to use for configuration.
+    #[arg(long, conflicts_with = "isolated")]
+    pub config: Option<PathBuf>,
+    /// Respect file exclusions via `.gitignore` and other standard ignore files.
+    #[arg(
+        long,
+        overrides_with("no_respect_gitignore"),
+        help_heading = "File selection"
+    )]
+    respect_gitignore: bool,
+    #[clap(long, overrides_with("respect_gitignore"), hide = true)]
+    no_respect_gitignore: bool,
+    /// Enforce exclusions, even for paths passed to Ruff directly on the command-line.
+    #[arg(
+        long,
+        overrides_with("no_force_exclude"),
+        help_heading = "File selection"
+    )]
+    force_exclude: bool,
+    #[clap(long, overrides_with("force_exclude"), hide = true)]
+    no_force_exclude: bool,
+    /// Set the line-length.
+    #[arg(long, help_heading = "Rule configuration", hide = true)]
+    pub line_length: Option<LineLength>,
+    /// Ignore all configuration files.
+    #[arg(long, conflicts_with = "config", help_heading = "Miscellaneous")]
+    pub isolated: bool,
+    /// The name of the file when passing it through stdin.
+    #[arg(long, help_heading = "Miscellaneous")]
+    pub stdin_filename: Option<PathBuf>,
+}
+
 #[derive(Debug, Clone, Copy, clap::ValueEnum)]
 pub enum HelpFormat {
     Text,
@@ -367,8 +391,7 @@ pub struct LogLevelArgs {
         help_heading = "Log levels"
     )]
     pub quiet: bool,
-    /// Disable all logging (but still exit with status code "1" upon detecting
+    /// Disable all logging (but still exit with status code "1" upon detecting lint violations).
-    /// lint violations).
     #[arg(
         short,
         long,
@@ -393,12 +416,12 @@ impl From<&LogLevelArgs> for LogLevel {
     }
 }
 
-impl CheckArgs {
+impl CheckCommand {
     /// Partition the CLI into command-line arguments and configuration
     /// overrides.
-    pub fn partition(self) -> (Arguments, Overrides) {
+    pub fn partition(self) -> (CheckArguments, Overrides) {
         (
-            Arguments {
+            CheckArguments {
                 add_noqa: self.add_noqa,
                 config: self.config,
                 diff: self.diff,
@@ -448,6 +471,32 @@ impl CheckArgs {
     }
 }
 
+impl FormatCommand {
+    /// Partition the CLI into command-line arguments and configuration
+    /// overrides.
+    pub fn partition(self) -> (FormatArguments, Overrides) {
+        (
+            FormatArguments {
+                config: self.config,
+                files: self.files,
+                isolated: self.isolated,
+                stdin_filename: self.stdin_filename,
+            },
+            Overrides {
+                line_length: self.line_length,
+                respect_gitignore: resolve_bool_arg(
+                    self.respect_gitignore,
+                    self.no_respect_gitignore,
+                ),
+                force_exclude: resolve_bool_arg(self.force_exclude, self.no_force_exclude),
+                target_version: self.target_version,
+                // Unsupported on the formatter CLI, but required on `Overrides`.
+                ..Overrides::default()
+            },
+        )
+    }
+}
+
 fn parse_rule_selector(env: &str) -> Result<RuleSelector, std::io::Error> {
     RuleSelector::from_str(env)
         .map_err(|e| std::io::Error::new(std::io::ErrorKind::InvalidInput, e))
@@ -465,7 +514,7 @@ fn resolve_bool_arg(yes: bool, no: bool) -> Option<bool> {
 /// CLI settings that are distinct from configuration (commands, lists of files,
 /// etc.).
 #[allow(clippy::struct_excessive_bools)]
-pub struct Arguments {
+pub struct CheckArguments {
     pub add_noqa: bool,
     pub config: Option<PathBuf>,
     pub diff: bool,
@@ -484,6 +533,16 @@ pub struct Arguments {
     pub watch: bool,
 }
 
+/// CLI settings that are distinct from configuration (commands, lists of files,
+/// etc.).
+#[allow(clippy::struct_excessive_bools)]
+pub struct FormatArguments {
+    pub config: Option<PathBuf>,
+    pub files: Vec<PathBuf>,
+    pub isolated: bool,
+    pub stdin_filename: Option<PathBuf>,
+}
+
 /// CLI settings that function as configuration overrides.
 #[derive(Clone, Default)]
 #[allow(clippy::struct_excessive_bools)]

crates/ruff_cli/src/commands/format.rs

@@ -16,12 +16,12 @@ use ruff_python_ast::{PySourceType, SourceType};
 use ruff_python_formatter::{format_module, FormatModuleError, PyFormatOptions};
 use ruff_workspace::resolver::python_files_in_path;
 
-use crate::args::{Arguments, Overrides};
+use crate::args::{FormatArguments, Overrides};
 use crate::resolve::resolve;
 use crate::ExitStatus;
 
 /// Format a set of files, and return the exit status.
-pub(crate) fn format(cli: &Arguments, overrides: &Overrides) -> Result<ExitStatus> {
+pub(crate) fn format(cli: &FormatArguments, overrides: &Overrides) -> Result<ExitStatus> {
     let pyproject_config = resolve(
         cli.isolated,
         cli.config.as_deref(),
@@ -59,7 +59,7 @@ pub(crate) fn format(cli: &Arguments, overrides: &Overrides) -> Result<ExitStatu
                 err
             })
         })
-        .collect::<Result<Vec<_>, _>>();
+        .collect::<Result<(), _>>();
 
     if result.is_ok() {
         Ok(ExitStatus::Success)

crates/ruff_cli/src/lib.rs

@@ -6,7 +6,6 @@ use std::sync::mpsc::channel;
 
 use anyhow::Result;
 use clap::CommandFactory;
-use clap::FromArgMatches;
 use log::warn;
 use notify::{recommended_watcher, RecursiveMode, Watcher};
 
@@ -16,7 +15,7 @@ use ruff::settings::{flags, CliSettings};
 use ruff::{fs, warn_user_once};
 use ruff_python_formatter::{format_module, PyFormatOptions};
 
-use crate::args::{Args, CheckArgs, Command};
+use crate::args::{Args, CheckCommand, Command, FormatCommand};
 use crate::commands::run_stdin::read_from_stdin;
 use crate::printer::{Flags as PrinterFlags, Printer};
 
@@ -149,27 +148,19 @@ quoting the executed command, along with the relevant file contents and `pyproje
             shell.generate(&mut Args::command(), &mut stdout());
         }
         Command::Check(args) => return check(args, log_level),
-        Command::Format { files } => return format(&files),
+        Command::Format(args) => return format(args),
     }
 
     Ok(ExitStatus::Success)
 }
 
-fn format(paths: &[PathBuf]) -> Result<ExitStatus> {
+fn format(args: FormatCommand) -> Result<ExitStatus> {
     warn_user_once!(
         "`ruff format` is a work-in-progress, subject to change at any time, and intended only for \
         experimentation."
     );
 
-    // We want to use the same as `ruff check <files>`, but we don't actually want to allow
+    let (cli, overrides) = args.partition();
-    // any of the linter settings.
-    // TODO(konstin): Refactor this to allow getting config and resolver without going
-    // though clap.
-    let args_matches = CheckArgs::command()
-        .no_binary_name(true)
-        .get_matches_from(paths);
-    let check_args: CheckArgs = CheckArgs::from_arg_matches(&args_matches)?;
-    let (cli, overrides) = check_args.partition();
 
     if is_stdin(&cli.files, cli.stdin_filename.as_deref()) {
         let unformatted = read_from_stdin()?;
@@ -186,7 +177,7 @@ fn format(paths: &[PathBuf]) -> Result<ExitStatus> {
     }
 }
 
-pub fn check(args: CheckArgs, log_level: LogLevel) -> Result<ExitStatus> {
+pub fn check(args: CheckCommand, log_level: LogLevel) -> Result<ExitStatus> {
     let (cli, overrides) = args.partition();
 
     // Construct the "default" settings. These are used when no `pyproject.toml`

crates/ruff_dev/src/format_dev.rs

@@ -1,23 +1,3 @@
-use anyhow::{bail, format_err, Context, Error};
-use clap::{CommandFactory, FromArgMatches};
-use ignore::DirEntry;
-use imara_diff::intern::InternedInput;
-use imara_diff::sink::Counter;
-use imara_diff::{diff, Algorithm};
-use indicatif::ProgressStyle;
-#[cfg_attr(feature = "singlethreaded", allow(unused_imports))]
-use rayon::iter::{IntoParallelIterator, ParallelIterator};
-use ruff::logging::LogLevel;
-use ruff::settings::types::{FilePattern, FilePatternSet};
-use ruff_cli::args::{CheckArgs, LogLevelArgs};
-use ruff_cli::resolve::resolve;
-use ruff_formatter::{FormatError, LineWidth, PrintError};
-use ruff_python_formatter::{
-    format_module, FormatModuleError, MagicTrailingComma, PyFormatOptions,
-};
-use ruff_workspace::resolver::python_files_in_path;
-use serde::Deserialize;
-use similar::{ChangeTag, TextDiff};
 use std::fmt::{Display, Formatter};
 use std::fs::File;
 use std::io::{BufWriter, Write};
@@ -28,6 +8,18 @@ use std::path::{Path, PathBuf};
 use std::process::ExitCode;
 use std::time::{Duration, Instant};
 use std::{fmt, fs, io, iter};
+
+use anyhow::{bail, format_err, Context, Error};
+use clap::{CommandFactory, FromArgMatches};
+use ignore::DirEntry;
+use imara_diff::intern::InternedInput;
+use imara_diff::sink::Counter;
+use imara_diff::{diff, Algorithm};
+use indicatif::ProgressStyle;
+#[cfg_attr(feature = "singlethreaded", allow(unused_imports))]
+use rayon::iter::{IntoParallelIterator, ParallelIterator};
+use serde::Deserialize;
+use similar::{ChangeTag, TextDiff};
 use tempfile::NamedTempFile;
 use tracing::{debug, error, info, info_span};
 use tracing_indicatif::span_ext::IndicatifSpanExt;
@@ -36,13 +28,23 @@ use tracing_subscriber::layer::SubscriberExt;
 use tracing_subscriber::util::SubscriberInitExt;
 use tracing_subscriber::EnvFilter;
 
+use ruff::logging::LogLevel;
+use ruff::settings::types::{FilePattern, FilePatternSet};
+use ruff_cli::args::{FormatCommand, LogLevelArgs};
+use ruff_cli::resolve::resolve;
+use ruff_formatter::{FormatError, LineWidth, PrintError};
+use ruff_python_formatter::{
+    format_module, FormatModuleError, MagicTrailingComma, PyFormatOptions,
+};
+use ruff_workspace::resolver::python_files_in_path;
+
 /// Find files that ruff would check so we can format them. Adapted from `ruff_cli`.
 fn ruff_check_paths(dirs: &[PathBuf]) -> anyhow::Result<Vec<Result<DirEntry, ignore::Error>>> {
-    let args_matches = CheckArgs::command()
+    let args_matches = FormatCommand::command()
         .no_binary_name(true)
         .get_matches_from(dirs);
-    let check_args: CheckArgs = CheckArgs::from_arg_matches(&args_matches)?;
+    let arguments: FormatCommand = FormatCommand::from_arg_matches(&args_matches)?;
-    let (cli, overrides) = check_args.partition();
+    let (cli, overrides) = arguments.partition();
     let mut pyproject_config = resolve(
         cli.isolated,
         cli.config.as_deref(),

crates/ruff_dev/src/main.rs

@@ -56,7 +56,7 @@ enum Command {
     /// Run a ruff command n times for profiling/benchmarking
     Repeat {
         #[clap(flatten)]
-        args: ruff_cli::args::CheckArgs,
+        args: ruff_cli::args::CheckCommand,
         #[clap(flatten)]
         log_level_args: ruff_cli::args::LogLevelArgs,
         /// Run this many times