4 files changed, 213 insertions, 79 deletions

diff --git a/Cargo.lock b/Cargo.lock
index 9092a87d3..f4b5d12a3 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -838,6 +838,11 @@ dependencies = [
 ]
 
 [[package]]
+name = "pico-args"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
 name = "ppv-lite86"
 version = "0.2.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -930,9 +935,9 @@ dependencies = [
 name = "ra_cli"
 version = "0.1.0"
 dependencies = [
- "clap 2.33.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "flexi_logger 0.14.3 (registry+https://github.com/rust-lang/crates.io-index)",
  "indicatif 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "pico-args 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "ra_batch 0.1.0",
  "ra_db 0.1.0",
  "ra_hir 0.1.0",
@@ -1873,6 +1878,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum paste-impl 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)" = "4214c9e912ef61bf42b81ba9a47e8aad1b2ffaf739ab162bf96d1e011f54e6c5"
 "checksum percent-encoding 2.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "d4fd5641d01c8f18a23da7b6fe29298ff4b55afcccdf78973b24cf3175fee32e"
 "checksum petgraph 0.4.13 (registry+https://github.com/rust-lang/crates.io-index)" = "9c3659d1ee90221741f65dd128d9998311b0e40c5d3c23a62445938214abce4f"
+"checksum pico-args 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "2fce25154205cf4360b456fd7d48994afe20663b77e3bd3d0a353a2fccf7f22c"
 "checksum ppv-lite86 0.2.5 (registry+https://github.com/rust-lang/crates.io-index)" = "e3cbf9f658cdb5000fcf6f362b8ea2ba154b9f146a61c7a20d647034c6b6561b"
 "checksum proc-macro-hack 0.5.9 (registry+https://github.com/rust-lang/crates.io-index)" = "e688f31d92ffd7c1ddc57a1b4e6d773c0f2a14ee437a4b0a4f5a69c80eb221c8"
 "checksum proc-macro2 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)" = "175a40b9cf564ce9bf050654633dbf339978706b8ead1a907bb970b63185dd95"
diff --git a/crates/ra_cli/Cargo.toml b/crates/ra_cli/Cargo.toml
index 205dd223b..d42ac3ad4 100644
--- a/crates/ra_cli/Cargo.toml
+++ b/crates/ra_cli/Cargo.toml
@@ -6,7 +6,7 @@ authors = ["rust-analyzer developers"]
 publish = false
 
 [dependencies]
-clap = { version = "2.32.0", default-features = false }
+pico-args = "0.2.0"
 flexi_logger = "0.14.0"
 indicatif = "0.11.0"
 
diff --git a/crates/ra_cli/src/help.rs b/crates/ra_cli/src/help.rs
new file mode 100644
index 000000000..bf31472ac
--- /dev/null
+++ b/crates/ra_cli/src/help.rs
@@ -0,0 +1,96 @@
+pub fn print_global_help() {

+    println!(

+        "ra-cli

+

+USAGE:

+    ra_cli <SUBCOMMAND>

+

+FLAGS:

+    -h, --help        Prints help information

+

+SUBCOMMANDS:

+    analysis-bench

+    analysis-stats

+    highlight

+    parse

+    symbols"

+    )

+}

+

+pub fn print_analysis_bench_help() {

+    println!(

+        "ra_cli-analysis-bench

+

+USAGE:

+    ra_cli analysis-bench [FLAGS] [OPTIONS] [PATH]

+

+FLAGS:

+    -h, --help        Prints help information

+    -v, --verbose

+    

+OPTIONS:

+    --complete <PATH:LINE:COLUMN>    Compute completions at this location

+    --highlight <PATH>               Hightlight this file

+    

+ARGS:

+    <PATH>    Project to analyse"

+    )

+}

+

+pub fn print_analysis_stats_help() {

+    println!(

+        "ra-cli-analysis-stats

+

+USAGE:

+    ra_cli analysis-stats [FLAGS] [OPTIONS] [PATH]

+    

+FLAGS:

+    -h, --help            Prints help information

+        --memory-usage

+    -v, --verbose

+    

+OPTIONS:

+    -o <ONLY>

+    

+ARGS:

+    <PATH>"

+    )

+}

+

+pub fn print_highlight_help() {

+    println!(

+        "ra-cli-highlight

+    

+USAGE:

+    ra_cli highlight [FLAGS]

+    

+FLAGS:

+    -h, --help       Prints help information

+    -r, --rainbow"

+    )

+}

+

+pub fn print_symbols_help() {

+    println!(

+        "ra-cli-symbols

+    

+USAGE:

+    ra_cli highlight [FLAGS]

+    

+FLAGS:

+    -h, --help    Prints help inforamtion"

+    )

+}

+

+pub fn print_parse_help() {

+    println!(

+        "ra-cli-parse

+    

+USAGE:

+    ra_cli parse [FLAGS]

+    

+FLAGS:

+    -h, --help       Prints help inforamtion

+        --no-dump"

+    )

+}

diff --git a/crates/ra_cli/src/main.rs b/crates/ra_cli/src/main.rs
index de8191ca3..9e6f869c1 100644
--- a/crates/ra_cli/src/main.rs
+++ b/crates/ra_cli/src/main.rs
@@ -1,10 +1,11 @@
 mod analysis_stats;
 mod analysis_bench;
+mod help;
 
-use std::{error::Error, io::Read};
+use std::{error::Error, fmt::Write, io::Read};
 
-use clap::{App, Arg, SubCommand};
 use flexi_logger::Logger;
+use pico_args::Arguments;
 use ra_ide_api::{file_structure, Analysis};
 use ra_prof::profile;
 use ra_syntax::{AstNode, SourceFile};
@@ -13,93 +14,124 @@ type Result<T> = std::result::Result<T, Box<dyn Error + Send + Sync>>;
 
 fn main() -> Result<()> {
     Logger::with_env().start()?;
-    let matches = App::new("ra-cli")
-        .setting(clap::AppSettings::SubcommandRequiredElseHelp)
-        .subcommand(SubCommand::with_name("parse").arg(Arg::with_name("no-dump").long("--no-dump")))
-        .subcommand(SubCommand::with_name("symbols"))
-        .subcommand(
-            SubCommand::with_name("highlight")
-                .arg(Arg::with_name("rainbow").short("r").long("rainbow")),
-        )
-        .subcommand(
-            SubCommand::with_name("analysis-stats")
-                .arg(Arg::with_name("verbose").short("v").long("verbose"))
-                .arg(Arg::with_name("memory-usage").long("memory-usage"))
-                .arg(Arg::with_name("only").short("o").takes_value(true))
-                .arg(Arg::with_name("path")),
-        )
-        .subcommand(
-            SubCommand::with_name("analysis-bench")
-                .arg(Arg::with_name("verbose").short("v").long("verbose"))
-                .arg(
-                    Arg::with_name("highlight")
-                        .long("highlight")
-                        .takes_value(true)
-                        .conflicts_with("complete")
-                        .value_name("PATH")
-                        .help("highlight this file"),
-                )
-                .arg(
-                    Arg::with_name("complete")
-                        .long("complete")
-                        .takes_value(true)
-                        .conflicts_with("highlight")
-                        .value_name("PATH:LINE:COLUMN")
-                        .help("compute completions at this location"),
-                )
-                .arg(Arg::with_name("path").value_name("PATH").help("project to analyze")),
-        )
-        .get_matches();
-    match matches.subcommand() {
-        ("parse", Some(matches)) => {
-            let _p = profile("parsing");
-            let file = file()?;
-            if !matches.is_present("no-dump") {
-                println!("{:#?}", file.syntax());
+
+    let subcommand = std::env::args_os().nth(1);
+    if subcommand.is_none() {
+        help::print_global_help();
+        return Ok(());
+    }
+    let subcommand = subcommand.unwrap();
+    let mut args: Vec<_> = std::env::args_os().collect();
+    let mut matches = Arguments::from_vec(args.drain(2..).collect());
+
+    match &*subcommand.to_string_lossy() {
+        "parse" => {
+            if matches.contains(["-h", "--help"]) {
+                help::print_parse_help();
+                return Ok(());
+            } else {
+                let no_dump = matches.contains("--no-dump");
+                matches.finish().or_else(handle_extra_flags)?;
+
+                let _p = profile("parsing");
+                let file = file()?;
+                if !no_dump {
+                    println!("{:#?}", file.syntax());
+                }
+                std::mem::forget(file);
             }
-            std::mem::forget(file);
         }
-        ("symbols", _) => {
-            let file = file()?;
-            for s in file_structure(&file) {
-                println!("{:?}", s);
+        "symbols" => {
+            if matches.contains(["-h", "--help"]) {
+                help::print_symbols_help();
+                return Ok(());
+            } else {
+                matches.finish().or_else(handle_extra_flags)?;
+                let file = file()?;
+                for s in file_structure(&file) {
+                    println!("{:?}", s);
+                }
             }
         }
-        ("highlight", Some(matches)) => {
-            let (analysis, file_id) = Analysis::from_single_file(read_stdin()?);
-            let html = analysis.highlight_as_html(file_id, matches.is_present("rainbow")).unwrap();
-            println!("{}", html);
+        "highlight" => {
+            if matches.contains(["-h", "--help"]) {
+                help::print_highlight_help();
+                return Ok(());
+            } else {
+                let rainbow_opt = matches.contains(["-r", "--rainbow"]);
+                matches.finish().or_else(handle_extra_flags)?;
+                let (analysis, file_id) = Analysis::from_single_file(read_stdin()?);
+                let html = analysis.highlight_as_html(file_id, rainbow_opt).unwrap();
+                println!("{}", html);
+            }
         }
-        ("analysis-stats", Some(matches)) => {
-            let verbose = matches.is_present("verbose");
-            let memory_usage = matches.is_present("memory-usage");
-            let path = matches.value_of("path").unwrap_or("");
-            let only = matches.value_of("only");
-            analysis_stats::run(verbose, memory_usage, path.as_ref(), only)?;
+        "analysis-stats" => {
+            if matches.contains(["-h", "--help"]) {
+                help::print_analysis_stats_help();
+                return Ok(());
+            } else {
+                let verbose = matches.contains(["-v", "--verbose"]);
+                let memory_usage = matches.contains("--memory-usage");
+                let path = matches.value_from_str("--path")?.unwrap_or("".to_string());
+                let only = matches.value_from_str(["-o", "--only"])?.map(|v: String| v.to_owned());
+                matches.finish().or_else(handle_extra_flags)?;
+                analysis_stats::run(
+                    verbose,
+                    memory_usage,
+                    path.as_ref(),
+                    only.as_ref().map(String::as_ref),
+                )?;
+            }
         }
-        ("analysis-bench", Some(matches)) => {
-            let verbose = matches.is_present("verbose");
-            let path = matches.value_of("path").unwrap_or("");
-            let op = if let Some(path) = matches.value_of("highlight") {
-                analysis_bench::Op::Highlight { path: path.into() }
-            } else if let Some(path_line_col) = matches.value_of("complete") {
-                let (path_line, column) = rsplit_at_char(path_line_col, ':')?;
-                let (path, line) = rsplit_at_char(path_line, ':')?;
-                analysis_bench::Op::Complete {
-                    path: path.into(),
-                    line: line.parse()?,
-                    column: column.parse()?,
-                }
+        "analysis-bench" => {
+            if matches.contains(["-h", "--help"]) {
+                help::print_analysis_bench_help();
+                return Ok(());
             } else {
-                panic!("either --highlight or --complete must be set")
-            };
-            analysis_bench::run(verbose, path.as_ref(), op)?;
+                let verbose = matches.contains(["-v", "--verbose"]);
+                let path = matches.value_from_str("--path")?.unwrap_or("".to_string());
+                let highlight_path = matches.value_from_str("--highlight")?;
+                let complete_path = matches.value_from_str("--complete")?;
+                if highlight_path.is_some() && complete_path.is_some() {
+                    panic!("either --highlight or --complete must be set, not both")
+                }
+                let op = if let Some(path) = highlight_path {
+                    let path: String = path;
+                    analysis_bench::Op::Highlight { path: path.into() }
+                } else if let Some(path_line_col) = complete_path {
+                    let path_line_col: String = path_line_col;
+                    let (path_line, column) = rsplit_at_char(path_line_col.as_str(), ':')?;
+                    let (path, line) = rsplit_at_char(path_line, ':')?;
+                    analysis_bench::Op::Complete {
+                        path: path.into(),
+                        line: line.parse()?,
+                        column: column.parse()?,
+                    }
+                } else {
+                    panic!("either --highlight or --complete must be set")
+                };
+                matches.finish().or_else(handle_extra_flags)?;
+                analysis_bench::run(verbose, path.as_ref(), op)?;
+            }
         }
-        _ => unreachable!(),
+        _ => help::print_global_help(),
     }
     Ok(())
 }
 
+fn handle_extra_flags(e: pico_args::Error) -> Result<()> {
+    if let pico_args::Error::UnusedArgsLeft(flags) = e {
+        let mut invalid_flags = String::new();
+        for flag in flags {
+            write!(&mut invalid_flags, "{}, ", flag).expect("Error on write");
+        }
+        let (invalid_flags, _) = invalid_flags.split_at(invalid_flags.len() - 2);
+        Err(format!("Invalid flags: {}", invalid_flags).into())
+    } else {
+        Err(e.to_string().into())
+    }
+}
+
 fn file() -> Result<SourceFile> {
     let text = read_stdin()?;
     Ok(SourceFile::parse(&text).tree())