Replace structopt with clap for CLI (#188, #155)

Co-authored-by: Kai Ren <tyranron@gmail.com>

CHANGELOG.md

@@ -19,6 +19,7 @@ All user visible changes to `cucumber` crate will be documented in this file. Th
 - Bump up [MSRV] to 1.57 for better error reporting in `const` assertions. ([cef3d480])
 - Switch to [`gherkin`] crate instead of [`gherkin_rust`]. ([rev])
 - Renamed `@allow_skipped` built-in tag to `@allow.skipped`. ([#181])
+- Switched CLI to `clap` from `structopt`. ([#188])
 
 ### Added
 
@@ -60,6 +61,7 @@ All user visible changes to `cucumber` crate will be documented in this file. Th
 [#178]: /../../pull/178
 [#181]: /../../pull/181
 [#182]: /../../pull/182
+[#188]: /../../pull/188
 [cef3d480]: /../../commit/cef3d480579190425461ddb04a1248675248351e
 [rev]: /../../commit/rev-full
 [0110-1]: https://llg.cubic.org/docs/junit

Cargo.toml

@@ -39,6 +39,7 @@ timestamps = []
 [dependencies]
 async-trait = "0.1.40"
 atty = "0.2.14"
+clap = { version = "3.0.0-rc.7", features = ["derive"] }
 console = "0.15"
 derive_more = { version = "0.99.17", features = ["as_ref", "deref", "deref_mut", "display", "error", "from", "into"], default_features = false }
 either = "1.6"
@@ -50,7 +51,6 @@ linked-hash-map = "0.5.3"
 once_cell = { version = "1.8", features = ["parking_lot"] }
 regex = "1.5"
 sealed = "0.3"
-structopt = "0.3.25"
 
 # "macros" feature dependencies.
 cucumber-codegen = { version = "0.11.0-dev", path = "./codegen", optional = true }

src/cli.rs

@@ -29,10 +29,11 @@
 
 use gherkin::tagexpr::TagOperation;
 use regex::Regex;
-use structopt::StructOpt;
 
 use crate::writer::Coloring;
 
+pub use clap::{Args, Parser};
+
 // Workaround for overwritten doc-comments.
 // https://github.com/TeXitoi/structopt/issues/333#issuecomment-712265332
 #[cfg_attr(
@@ -51,7 +52,6 @@ and may be extended with custom CLI options additionally.
 # use async_trait::async_trait;
 # use cucumber::{cli, WorldInit};
 # use futures::FutureExt as _;
-# use structopt::StructOpt;
 # use tokio::time;
 #
 # #[derive(Debug, WorldInit)]
@@ -68,17 +68,17 @@ and may be extended with custom CLI options additionally.
 #
 # #[tokio::main(flavor = "current_thread")]
 # async fn main() {
-#[derive(StructOpt)]
+#[derive(clap::Args)]
 struct CustomOpts {
     /// Additional time to wait in before hook.
-    #[structopt(
+    #[clap(
         long,
         parse(try_from_str = humantime::parse_duration)
     )]
     pre_pause: Option<Duration>,
 }
 
-let opts = cli::Opts::<_, _, _, CustomOpts>::from_args();
+let opts = cli::Opts::<_, _, _, CustomOpts>::parsed();
 let pre_pause = opts.custom.pre_pause.unwrap_or_default();
 
 MyWorld::cucumber()
@@ -96,18 +96,18 @@ MyWorld::cucumber()
 "#
 )]
 #[cfg_attr(not(doc), doc = "Run the tests, pet a dog!.")]
-#[derive(Debug, Clone, StructOpt)]
-#[structopt(name = "cucumber", about = "Run the tests, pet a dog!.")]
+#[derive(Debug, Clone, clap::Parser)]
+#[clap(name = "cucumber", about = "Run the tests, pet a dog!.")]
 pub struct Opts<Parser, Runner, Writer, Custom = Empty>
 where
-    Parser: StructOpt,
-    Runner: StructOpt,
-    Writer: StructOpt,
-    Custom: StructOpt,
+    Parser: Args,
+    Runner: Args,
+    Writer: Args,
+    Custom: Args,
 {
     /// Regex to filter scenarios by their name.
-    #[structopt(
-        short = "n",
+    #[clap(
+        short = 'n',
         long = "name",
         name = "regex",
         visible_alias = "scenario-name"
@@ -118,8 +118,8 @@ where
     ///
     /// Note: Tags from Feature, Rule and Scenario are merged together on
     /// filtering, so be careful about conflicting tags on different levels.
-    #[structopt(
-        short = "t",
+    #[clap(
+        short = 't',
         long = "tags",
         name = "tagexpr",
         conflicts_with = "regex"
@@ -129,26 +129,41 @@ where
     /// [`Parser`] CLI options.
     ///
     /// [`Parser`]: crate::Parser
-    #[structopt(flatten)]
+    #[clap(flatten)]
     pub parser: Parser,
 
     /// [`Runner`] CLI options.
     ///
     /// [`Runner`]: crate::Runner
-    #[structopt(flatten)]
+    #[clap(flatten)]
     pub runner: Runner,
 
     /// [`Writer`] CLI options.
     ///
     /// [`Writer`]: crate::Writer
-    #[structopt(flatten)]
+    #[clap(flatten)]
     pub writer: Writer,
 
     /// Additional custom CLI options.
-    #[structopt(flatten)]
+    #[clap(flatten)]
     pub custom: Custom,
 }
 
+impl<Parser, Runner, Writer, Custom> Opts<Parser, Runner, Writer, Custom>
+where
+    Parser: Args,
+    Runner: Args,
+    Writer: Args,
+    Custom: Args,
+{
+    /// Shortcut for [`clap::Parser::parse()`], which doesn't require the trait
+    /// being imported.
+    #[must_use]
+    pub fn parsed() -> Self {
+        <Self as clap::Parser>::parse()
+    }
+}
+
 /// Indication whether a [`Writer`] using CLI options supports colored output.
 ///
 /// [`Writer`]: crate::Writer
@@ -170,14 +185,8 @@ pub trait Colored {
     not(doc),
     allow(missing_docs, clippy::missing_docs_in_private_items)
 )]
-#[derive(Clone, Copy, Debug, StructOpt)]
-pub struct Empty {
-    /// This field exists only because [`StructOpt`] derive macro doesn't
-    /// support unit structs.
-    #[allow(dead_code)]
-    #[structopt(skip)]
-    skipped: (),
-}
+#[derive(Args, Clone, Copy, Debug)]
+pub struct Empty;
 
 impl Colored for Empty {}
 
@@ -186,7 +195,7 @@ impl Colored for Empty {}
 #[cfg_attr(
     doc,
     doc = r#"
-Composes two [`StructOpt`] derivers together.
+Composes two [`clap::Args`] derivers together.
 
 # Example
 
@@ -195,13 +204,12 @@ another one:
 ```rust
 # use async_trait::async_trait;
 # use cucumber::{cli, event, parser, writer, Event, World, Writer};
-# use structopt::StructOpt;
 #
 struct CustomWriter<Wr>(Wr);
 
-#[derive(StructOpt)]
+#[derive(clap::Args)]
 struct Cli {
-    #[structopt(long)]
+    #[clap(long)]
     custom_option: Option<String>,
 }
 
@@ -277,18 +285,18 @@ impl<Wr: writer::NonTransforming> writer::NonTransforming
     not(doc),
     allow(missing_docs, clippy::missing_docs_in_private_items)
 )]
-#[derive(Debug, StructOpt)]
-pub struct Compose<L: StructOpt, R: StructOpt> {
-    /// Left [`StructOpt`] deriver.
-    #[structopt(flatten)]
+#[derive(Args, Debug)]
+pub struct Compose<L: Args, R: Args> {
+    /// Left [`clap::Args`] deriver.
+    #[clap(flatten)]
     pub left: L,
 
-    /// Right [`StructOpt`] deriver.
-    #[structopt(flatten)]
+    /// Right [`clap::Args`] deriver.
+    #[clap(flatten)]
     pub right: R,
 }
 
-impl<L: StructOpt, R: StructOpt> Compose<L, R> {
+impl<L: Args, R: Args> Compose<L, R> {
     /// Unpacks this [`Compose`] into the underlying CLIs.
     #[must_use]
     pub fn into_inner(self) -> (L, R) {
@@ -299,8 +307,8 @@ impl<L: StructOpt, R: StructOpt> Compose<L, R> {
 
 impl<L, R> Colored for Compose<L, R>
 where
-    L: Colored + StructOpt,
-    R: Colored + StructOpt,
+    L: Args + Colored,
+    R: Args + Colored,
 {
     fn coloring(&self) -> Coloring {
         // Basically, founds "maximum" `Coloring` of CLI options.

src/cucumber.rs

@@ -22,7 +22,6 @@ use std::{
 
 use futures::{future::LocalBoxFuture, StreamExt as _};
 use regex::Regex;
-use structopt::{StructOpt, StructOptInternal};
 
 use crate::{
     cli, event, parser, runner, step, tag::Ext as _, writer, Event, Parser,
@@ -54,7 +53,7 @@ where
     P: Parser<I>,
     R: Runner<W>,
     Wr: Writer<W>,
-    Cli: StructOpt,
+    Cli: clap::Args,
 {
     /// [`Parser`] sourcing [`Feature`]s for execution.
     ///
@@ -88,7 +87,7 @@ where
     P: Parser<I>,
     R: Runner<W>,
     Wr: Writer<W>,
-    Cli: StructOpt,
+    Cli: clap::Args,
 {
     /// Creates a custom [`Cucumber`] executor with the provided [`Parser`],
     /// [`Runner`] and [`Writer`].
@@ -437,7 +436,7 @@ where
     P: Parser<I>,
     R: Runner<W>,
     Wr: Writer<W> + for<'val> writer::Arbitrary<'val, W, String>,
-    Cli: StructOpt,
+    Cli: clap::Args,
 {
     /// Consider [`Skipped`] steps as [`Failed`] if their [`Scenario`] isn't
     /// marked with `@allow.skipped` tag.
@@ -627,7 +626,7 @@ where
     P: Parser<I>,
     R: Runner<W>,
     Wr: Writer<W> + writer::Normalized,
-    Cli: StructOpt + StructOptInternal,
+    Cli: clap::Args,
 {
     /// Runs [`Cucumber`].
     ///
@@ -645,7 +644,7 @@ where
     /// using them inside [`Cucumber`].
     ///
     /// Also, any additional custom CLI options may be specified as a
-    /// [`StructOpt`] deriving type, used as the last type parameter of
+    /// [`clap::Args`] deriving type, used as the last type parameter of
     /// [`cli::Opts`].
     ///
     /// > ⚠️ __WARNING__: Any CLI options of [`Parser`], [`Runner`], [`Writer`]
@@ -660,7 +659,6 @@ where
     /// # use async_trait::async_trait;
     /// # use cucumber::{cli, WorldInit};
     /// # use futures::FutureExt as _;
-    /// # use structopt::StructOpt;
     /// # use tokio::time;
     /// #
     /// # #[derive(Debug, WorldInit)]
@@ -677,17 +675,17 @@ where
     /// #
     /// # #[tokio::main(flavor = "current_thread")]
     /// # async fn main() {
-    /// #[derive(StructOpt)]
+    /// #[derive(clap::Args)]
     /// struct CustomCli {
     ///     /// Additional time to wait in a before hook.
-    ///     #[structopt(
+    ///     #[clap(
     ///         long,
     ///         parse(try_from_str = humantime::parse_duration)
     ///     )]
     ///     before_time: Option<Duration>,
     /// }
     ///
-    /// let cli = cli::Opts::<_, _, _, CustomCli>::from_args();
+    /// let cli = cli::Opts::<_, _, _, CustomCli>::parsed();
     /// let time = cli.custom.before_time.unwrap_or_default();
     ///
     /// MyWorld::cucumber()
@@ -719,7 +717,7 @@ where
         cli: cli::Opts<P::Cli, R::Cli, Wr::Cli, CustomCli>,
     ) -> Cucumber<W, P, I, R, Wr, CustomCli>
     where
-        CustomCli: StructOpt,
+        CustomCli: clap::Args,
     {
         let Cucumber {
             parser,
@@ -811,7 +809,7 @@ where
             runner: runner_cli,
             writer: writer_cli,
             ..
-        } = self.cli.unwrap_or_else(cli::Opts::<_, _, _, _>::from_args);
+        } = self.cli.unwrap_or_else(cli::Opts::<_, _, _, _>::parsed);
 
         let filter = move |feat: &gherkin::Feature,
                            rule: Option<&gherkin::Rule>,
@@ -884,7 +882,7 @@ where
     P: Debug + Parser<I>,
     R: Debug + Runner<W>,
     Wr: Debug + Writer<W>,
-    Cli: StructOpt,
+    Cli: clap::Args,
 {
     fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
         f.debug_struct("Cucumber")
@@ -954,7 +952,7 @@ where
     W: World,
     R: Runner<W>,
     Wr: Writer<W>,
-    Cli: StructOpt,
+    Cli: clap::Args,
     I: AsRef<Path>,
 {
     /// Sets the provided language of [`gherkin`] files.
@@ -977,7 +975,7 @@ where
     W: World,
     P: Parser<I>,
     Wr: Writer<W>,
-    Cli: StructOpt,
+    Cli: clap::Args,
     F: Fn(
             &gherkin::Feature,
             Option<&gherkin::Rule>,
@@ -1176,7 +1174,7 @@ where
     P: Parser<I>,
     R: Runner<W>,
     Wr: writer::Failure<W> + writer::Normalized,
-    Cli: StructOpt + StructOptInternal,
+    Cli: clap::Args,
 {
     /// Runs [`Cucumber`].
     ///

src/parser/basic.rs

@@ -23,7 +23,6 @@ use futures::stream;
 use gherkin::GherkinEnv;
 use globwalk::{GlobWalker, GlobWalkerBuilder};
 use itertools::Itertools as _;
-use structopt::StructOpt;
 
 use crate::feature::Ext as _;
 
@@ -36,11 +35,11 @@ use super::{Error as ParseError, Parser};
     not(doc),
     allow(missing_docs, clippy::missing_docs_in_private_items)
 )]
-#[derive(Debug, StructOpt)]
+#[derive(Debug, clap::Parser)]
 pub struct Cli {
     /// Glob pattern to look for feature files with. By default, looks for
     /// `*.feature`s in the path configured tests runner.
-    #[structopt(long = "input", short = "i", name = "glob")]
+    #[clap(long = "input", short = 'i', name = "glob")]
     pub features: Option<Walker>,
 }