Add support for shell-completions file generation (#76)

* Add shell-completions file generation support

* Update CHANGELOG

---------

Co-authored-by: Brad Larsen <[email protected]>

CHANGELOG.md

@@ -12,6 +12,10 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 - A default value (`datastore.np`) is now set for commands that take a datastore option ([#74](https://github.com/praetorian-inc/noseyparker/issues/74)).
   This makes simpler `noseyparker` command-line invocations possible.
 
+- A new `shell-completions` command has been added, which generates shell-specific completion scripts for zsh, bash, fish, powershell, and elvish ([#76](https://github.com/praetorian-inc/noseyparker/pull/76)).
+  These generated completion scripts make discovery of Nosey Parker's command-line API simpler.
+  Thank you @Coruscant11!
+
 
 ## [v0.14.0](https://github.com/praetorian-inc/noseyparker/releases/v0.14.0) (2023-08-17)
 

crates/noseyparker-cli/Cargo.toml

@@ -36,6 +36,7 @@ vergen = { version = "8.1", features = ["build", "cargo", "git", "gitcl", "rustc
 anyhow = { version = "1.0" }
 bstr = { version = "1.0" }
 clap = { version = "4.3", features = ["cargo", "derive", "env", "unicode", "wrap_help"] }
+clap_complete = "4.4"
 console = "0.15"
 crossbeam-channel = "0.5"
 indenter = "0.3"

crates/noseyparker-cli/src/bin/noseyparker/args.rs

@@ -168,6 +168,10 @@ pub enum Command {
     #[command(display_order = 30)]
     /// Manage rules
     Rules(RulesArgs),
+
+    #[command(display_order = 30)]
+    /// Generate shell completions
+    ShellCompletions(ShellCompletionsArgs),
 }
 
 // -----------------------------------------------------------------------------
@@ -612,6 +616,39 @@ pub struct ReportArgs {
     pub output_args: OutputArgs,
 }
 
+
+// -----------------------------------------------------------------------------
+// `shell_completions` command
+// -----------------------------------------------------------------------------
+#[derive(ValueEnum, Debug, Clone)]
+#[clap(rename_all = "lower")]
+pub enum ShellFormat {
+    Bash,
+    Zsh,
+    Fish,
+    PowerShell,
+    Elvish
+}
+
+impl std::fmt::Display for ShellFormat {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        let s = match self {
+            ShellFormat::Bash => "bash",
+            ShellFormat::Zsh => "zsh",
+            ShellFormat::Fish => "fish",
+            ShellFormat::PowerShell => "powershell",
+            ShellFormat::Elvish => "elvish",
+        };
+        write!(f, "{s}")
+    }
+}
+
+#[derive(Args, Debug)]
+pub struct ShellCompletionsArgs {
+    #[arg(long, short, value_name = "SHELL")]
+    pub shell: ShellFormat,
+}
+
 // -----------------------------------------------------------------------------
 // output options
 // -----------------------------------------------------------------------------

crates/noseyparker-cli/src/bin/noseyparker/cmd_shell_completions.rs

@@ -0,0 +1,24 @@
+use crate::args::{GlobalArgs, ShellFormat, ShellCompletionsArgs, CommandLineArgs};
+use anyhow::Result;
+use clap::{CommandFactory, Command};
+use clap_complete::{generate, shells::Bash, shells::Zsh, shells::Fish, shells::PowerShell, shells::Elvish};
+
+pub fn run(_global_args: &GlobalArgs, args: &ShellCompletionsArgs) -> Result<()> {
+    let mut cmd = CommandLineArgs::command();
+    generate_completions_for_shell(&args.shell, &mut cmd)
+}
+
+fn generate_completions_for_shell(shell: &ShellFormat, cmd: &mut Command) -> Result<()> {
+    let bin_name = "noseyparker";
+    let std_out = &mut std::io::stdout();
+
+    match shell {
+        ShellFormat::Bash => generate(Bash, cmd, bin_name, std_out),
+        ShellFormat::Zsh => generate(Zsh, cmd, bin_name, std_out),
+        ShellFormat::Fish => generate(Fish, cmd, bin_name, std_out),
+        ShellFormat::PowerShell => generate(PowerShell, cmd, bin_name, std_out),
+        ShellFormat::Elvish => generate(Elvish, cmd, bin_name, std_out),
+    }
+
+    Ok(())
+}

crates/noseyparker-cli/src/bin/noseyparker/main.rs

@@ -7,6 +7,7 @@ mod cmd_github;
 mod cmd_report;
 mod cmd_rules;
 mod cmd_scan;
+mod cmd_shell_completions;
 mod cmd_summarize;
 
 use args::GlobalArgs;
@@ -80,6 +81,7 @@ fn try_main() -> Result<()> {
         args::Command::Scan(args) => cmd_scan::run(global_args, args),
         args::Command::Summarize(args) => cmd_summarize::run(global_args, args),
         args::Command::Report(args) => cmd_report::run(global_args, args),
+        args::Command::ShellCompletions(args) => cmd_shell_completions::run(global_args, args),
     }
 }
 

crates/noseyparker-cli/tests/help/snapshots/test_noseyparker__help__help-2.snap

@@ -8,13 +8,14 @@ and Git history.
 Usage: noseyparker [OPTIONS] <COMMAND>
 
 Commands:
-  scan       Scan content for secrets
-  summarize  Summarize scan findings
-  report     Report detailed scan findings
-  github     Interact with GitHub
-  datastore  Manage datastores
-  rules      Manage rules
-  help       Print this message or the help of the given subcommand(s)
+  scan               Scan content for secrets
+  summarize          Summarize scan findings
+  report             Report detailed scan findings
+  github             Interact with GitHub
+  datastore          Manage datastores
+  rules              Manage rules
+  shell-completions  Generate shell completions
+  help               Print this message or the help of the given subcommand(s)
 
 Options:
   -h, --help

crates/noseyparker-cli/tests/help/snapshots/test_noseyparker__help__help_short-2.snap

@@ -8,13 +8,14 @@ and Git history.
 Usage: noseyparker [OPTIONS] <COMMAND>
 
 Commands:
-  scan       Scan content for secrets
-  summarize  Summarize scan findings
-  report     Report detailed scan findings
-  github     Interact with GitHub
-  datastore  Manage datastores
-  rules      Manage rules
-  help       Print this message or the help of the given subcommand(s)
+  scan               Scan content for secrets
+  summarize          Summarize scan findings
+  report             Report detailed scan findings
+  github             Interact with GitHub
+  datastore          Manage datastores
+  rules              Manage rules
+  shell-completions  Generate shell completions
+  help               Print this message or the help of the given subcommand(s)
 
 Options:
   -h, --help     Print help (see more with '--help')

crates/noseyparker-cli/tests/help/snapshots/test_noseyparker__help__no_args-3.snap

@@ -8,13 +8,14 @@ and Git history.
 Usage: noseyparker [OPTIONS] <COMMAND>
 
 Commands:
-  scan       Scan content for secrets
-  summarize  Summarize scan findings
-  report     Report detailed scan findings
-  github     Interact with GitHub
-  datastore  Manage datastores
-  rules      Manage rules
-  help       Print this message or the help of the given subcommand(s)
+  scan               Scan content for secrets
+  summarize          Summarize scan findings
+  report             Report detailed scan findings
+  github             Interact with GitHub
+  datastore          Manage datastores
+  rules              Manage rules
+  shell-completions  Generate shell completions
+  help               Print this message or the help of the given subcommand(s)
 
 Options:
   -h, --help     Print help (see more with '--help')