Remove the 'env' command, as we have the variable (#8185)

# Description

Removes the `env` command, as the `$env` is generally a much better
experience.

# User-Facing Changes

Breaking change: Removes `env`.

# Tests + Formatting

Don't forget to add tests that cover your changes.

Make sure you've run and fixed any issues with these commands:

- `cargo fmt --all -- --check` to check standard code formatting (`cargo
fmt --all` applies these changes)
- `cargo clippy --workspace -- -D warnings -D clippy::unwrap_used -A
clippy::needless_collect` to check that you're using the standard code
style
- `cargo test --workspace` to check that all tests pass

# After Submitting

If your PR had any user-facing changes, update [the
documentation](https://github.com/nushell/nushell.github.io) after the
PR is merged, if necessary. This will help us keep the docs up to date.

crates/nu-command/src/default_context.rs

@@ -343,7 +343,6 @@ pub fn create_default_context() -> EngineState {
 
         // Env
         bind_command! {
-            Env,
             ExportEnv,
             LetEnv,
             LoadEnv,

crates/nu-command/src/env/env_command.rs

@@ -1,90 +0,0 @@
-use nu_engine::env_to_string;
-use nu_protocol::ast::Call;
-use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{
-    Category, Example, IntoPipelineData, PipelineData, ShellError, Signature, Type, Value,
-};
-
-#[derive(Clone)]
-pub struct Env;
-
-impl Command for Env {
-    fn name(&self) -> &str {
-        "env"
-    }
-
-    fn usage(&self) -> &str {
-        "Display current environment variables."
-    }
-
-    fn signature(&self) -> nu_protocol::Signature {
-        Signature::build("env")
-            .category(Category::Env)
-            .input_output_types(vec![(Type::Nothing, Type::Table(vec![]))])
-    }
-
-    fn run(
-        &self,
-        engine_state: &EngineState,
-        stack: &mut Stack,
-        call: &Call,
-        _input: PipelineData,
-    ) -> Result<PipelineData, ShellError> {
-        let span = call.head;
-
-        let mut env_vars: Vec<(String, Value)> =
-            stack.get_env_vars(engine_state).into_iter().collect();
-        env_vars.sort_by(|(name1, _), (name2, _)| name1.cmp(name2));
-
-        let mut values = vec![];
-
-        for (name, val) in env_vars {
-            let mut cols = vec![];
-            let mut vals = vec![];
-
-            let raw_val = match env_to_string(&name, &val, engine_state, stack) {
-                Ok(raw) => Value::string(raw, span),
-                Err(ShellError::EnvVarNotAString(..)) => Value::nothing(span),
-                Err(e) => return Err(e),
-            };
-
-            let val_type = val.get_type();
-
-            cols.push("name".into());
-            vals.push(Value::string(name, span));
-
-            cols.push("type".into());
-            vals.push(Value::string(format!("{val_type}"), span));
-
-            cols.push("value".into());
-            vals.push(val);
-
-            cols.push("raw".into());
-            vals.push(raw_val);
-
-            values.push(Value::Record { cols, vals, span });
-        }
-
-        Ok(Value::List { vals: values, span }.into_pipeline_data())
-    }
-
-    fn examples(&self) -> Vec<Example> {
-        vec![
-            Example {
-                description: "Display current path environment variable",
-                example: "env | where name == PATH",
-                result: None,
-            },
-            Example {
-                description: "Check whether the env variable `MY_ENV_ABC` exists",
-                example: r#"env | any { |e| $e.name == MY_ENV_ABC }"#,
-                result: Some(Value::test_bool(false)),
-            },
-            Example {
-                description: "Another way to check whether the env variable `PATH` exists",
-                example: r#"'PATH' in (env).name"#,
-                result: Some(Value::test_bool(true)),
-            },
-        ]
-    }
-}

crates/nu-command/src/env/mod.rs

@@ -1,5 +1,4 @@
 mod config;
-mod env_command;
 mod export_env;
 mod let_env;
 mod load_env;
@@ -10,7 +9,6 @@ pub use config::ConfigEnv;
 pub use config::ConfigMeta;
 pub use config::ConfigNu;
 pub use config::ConfigReset;
-pub use env_command::Env;
 pub use export_env::ExportEnv;
 pub use let_env::LetEnv;
 pub use load_env::LoadEnv;

src/tests/test_env.rs

@@ -14,11 +14,3 @@ fn shorthand_env_2() -> TestResult {
 fn shorthand_env_3() -> TestResult {
     run_test(r#"FOO=BAZ BAR=MOO $env.FOO"#, "BAZ")
 }
-
-#[test]
-fn convert_non_string_env_var_to_nothing() -> TestResult {
-    run_test(
-        r#"let-env FOO = true; env | where name == FOO | get raw.0 | describe"#,
-        "nothing",
-    )
-}

src/tests/test_parser.rs

@@ -234,7 +234,7 @@ fn equals_separates_long_flag() -> TestResult {
 fn let_env_expressions() -> TestResult {
     let env = HashMap::from([("VENV_OLD_PATH", "Foobar"), ("Path", "Quux")]);
     run_test_with_env(
-        r#"let-env Path = if (env | any {|x| $x.name == VENV_OLD_PATH}) { $env.VENV_OLD_PATH } else { $env.Path }; echo $env.Path"#,
+        r#"let-env Path = if ($env | columns | "VENV_OLD_PATH" in $in) { $env.VENV_OLD_PATH } else { $env.Path }; echo $env.Path"#,
         "Foobar",
         &env,
     )