Introduce version command

src/cli.rs

@@ -194,6 +194,7 @@ pub async fn cli() -> Result<(), Box<dyn Error>> {
             whole_stream_command(Save),
             whole_stream_command(Table),
             whole_stream_command(VTable),
+            whole_stream_command(Version),
             whole_stream_command(Which),
         ]);
     }

src/commands.rs

@@ -50,6 +50,7 @@ crate mod to_json;
 crate mod to_toml;
 crate mod to_yaml;
 crate mod trim;
+crate mod version;
 crate mod vtable;
 crate mod where_;
 crate mod which_;
@@ -74,6 +75,7 @@ crate use rm::Remove;
 crate use save::Save;
 crate use skip_while::SkipWhile;
 crate use table::Table;
+crate use version::Version;
 crate use vtable::VTable;
 crate use where_::Where;
 crate use which_::Which;

src/commands/version.rs

@@ -0,0 +1,42 @@
+use crate::commands::WholeStreamCommand;
+use crate::errors::ShellError;
+use crate::object::{Dictionary, Value};
+use crate::parser::registry::Signature;
+use crate::prelude::*;
+use indexmap::IndexMap;
+
+const VERSION: &'static str = env!("CARGO_PKG_VERSION");
+
+pub struct Version;
+
+impl WholeStreamCommand for Version {
+    fn run(
+        &self,
+        args: CommandArgs,
+        registry: &CommandRegistry,
+    ) -> Result<OutputStream, ShellError> {
+        date(args, registry)
+    }
+
+    fn name(&self) -> &str {
+        "version"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("version")
+    }
+}
+
+pub fn date(args: CommandArgs, registry: &CommandRegistry) -> Result<OutputStream, ShellError> {
+    let args = args.evaluate_once(registry)?;
+    let span = args.call_info.name_span;
+
+    let mut indexmap = IndexMap::new();
+    indexmap.insert(
+        "version".to_string(),
+        Tagged::from_simple_spanned_item(Value::string(VERSION.to_string()), span),
+    );
+
+    let value = Tagged::from_simple_spanned_item(Value::Object(Dictionary::from(indexmap)), span);
+    Ok(OutputStream::one(value))
+}