Add format duration to replace into duration --convert (#9788)

# Description
Add `format duration` cmd to choose output unit.

This takes the previous `into duration --convert ...` behavior which
returned a string into its own `format duration` command.
This was suprising and not fitting with the general type signature for
the `into ...` commands.

This command for now lives in the `nu-cmd-extra` nursery.

# User-Facing Changes
## Breaking change
Removes formatting behavior from `into duration`
Now use `format duration` instead of `into duration --convert`
## Usage:
```
1sec | format duration us # Output data in microseconds
"2ms" | into duration | format duration sec # go from string to string
```


# Tests + Formatting
Basic example testing (including basic broadcast)

crates/nu-cmd-extra/src/extra/mod.rs

@@ -86,6 +86,7 @@ pub fn add_extra_command_context(mut engine_state: EngineState) -> EngineState {
         bind_command!(
             strings::format::Format,
             strings::format::FileSize,
+            strings::format::FormatDuration,
             strings::encode_decode::EncodeHex,
             strings::encode_decode::DecodeHex
         );

crates/nu-cmd-extra/src/extra/strings/format/duration.rs

@@ -0,0 +1,197 @@
+use nu_cmd_base::input_handler::{operate, CmdArgument};
+use nu_engine::CallExt;
+use nu_protocol::ast::{Call, CellPath};
+use nu_protocol::engine::{Command, EngineState, Stack};
+use nu_protocol::{
+    Category, Example, PipelineData, ShellError, Signature, Span, SyntaxShape, Type, Value,
+};
+
+struct Arguments {
+    format_value: String,
+    float_precision: usize,
+    cell_paths: Option<Vec<CellPath>>,
+}
+
+impl CmdArgument for Arguments {
+    fn take_cell_paths(&mut self) -> Option<Vec<CellPath>> {
+        self.cell_paths.take()
+    }
+}
+
+#[derive(Clone)]
+pub struct FormatDuration;
+
+impl Command for FormatDuration {
+    fn name(&self) -> &str {
+        "format duration"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("format duration")
+            .input_output_types(vec![
+                (Type::Duration, Type::String),
+                (
+                    Type::List(Box::new(Type::Duration)),
+                    Type::List(Box::new(Type::String)),
+                ),
+                (Type::Table(vec![]), Type::Table(vec![])),
+            ])
+            .allow_variants_without_examples(true)
+            .required(
+                "format value",
+                SyntaxShape::String,
+                "the unit in which to display the duration",
+            )
+            .rest(
+                "rest",
+                SyntaxShape::CellPath,
+                "For a data structure input, format duration at the given cell paths",
+            )
+            .category(Category::Strings)
+    }
+
+    fn usage(&self) -> &str {
+        "Outputs duration with a specified unit of time."
+    }
+
+    fn search_terms(&self) -> Vec<&str> {
+        vec!["convert", "display", "pattern", "human readable"]
+    }
+
+    fn run(
+        &self,
+        engine_state: &EngineState,
+        stack: &mut Stack,
+        call: &Call,
+        input: PipelineData,
+    ) -> Result<PipelineData, ShellError> {
+        let format_value = call
+            .req::<Value>(engine_state, stack, 0)?
+            .as_string()?
+            .to_ascii_lowercase();
+        let cell_paths: Vec<CellPath> = call.rest(engine_state, stack, 1)?;
+        let cell_paths = (!cell_paths.is_empty()).then_some(cell_paths);
+        let float_precision = engine_state.config.float_precision as usize;
+        let arg = Arguments {
+            format_value,
+            float_precision,
+            cell_paths,
+        };
+        operate(
+            format_value_impl,
+            arg,
+            input,
+            call.head,
+            engine_state.ctrlc.clone(),
+        )
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![
+            Example {
+                description: "Convert µs duration to the requested second duration as a string",
+                example: "1000000µs | format duration sec",
+                result: Some(Value::test_string("1 sec")),
+            },
+            Example {
+                description: "Convert durations to µs duration as strings",
+                example: "[1sec 2sec] | format duration µs",
+                result: Some(Value::test_list(vec![
+                    Value::test_string("1000000 µs"),
+                    Value::test_string("2000000 µs"),
+                ])),
+            },
+            Example {
+                description: "Convert duration to µs as a string if unit asked for was us",
+                example: "1sec | format duration us",
+                result: Some(Value::test_string("1000000 µs")),
+            },
+        ]
+    }
+}
+
+fn format_value_impl(val: &Value, arg: &Arguments, span: Span) -> Value {
+    match val {
+        Value::Duration {
+            val: inner,
+            span: inner_span,
+        } => {
+            let duration = *inner;
+            let float_precision = arg.float_precision;
+            match convert_inner_to_unit(duration, &arg.format_value, span, *inner_span) {
+                Ok(d) => {
+                    let unit = if &arg.format_value == "us" {
+                        "µs"
+                    } else {
+                        &arg.format_value
+                    };
+                    if d.fract() == 0.0 {
+                        Value::String {
+                            val: format!("{} {}", d, unit),
+                            span: *inner_span,
+                        }
+                    } else {
+                        Value::String {
+                            val: format!("{:.float_precision$} {}", d, unit),
+                            span: *inner_span,
+                        }
+                    }
+                }
+                Err(e) => Value::Error { error: Box::new(e) },
+            }
+        }
+        Value::Error { .. } => val.clone(),
+        _ => Value::Error {
+            error: Box::new(ShellError::OnlySupportsThisInputType {
+                exp_input_type: "filesize".into(),
+                wrong_type: val.get_type().to_string(),
+                dst_span: span,
+                src_span: val.expect_span(),
+            }),
+        },
+    }
+}
+
+fn convert_inner_to_unit(
+    val: i64,
+    to_unit: &str,
+    span: Span,
+    value_span: Span,
+) -> Result<f64, ShellError> {
+    match to_unit {
+        "ns" => Ok(val as f64),
+        "us" => Ok(val as f64 / 1000.0),
+        "µs" => Ok(val as f64 / 1000.0), // Micro sign
+        "μs" => Ok(val as f64 / 1000.0), // Greek small letter
+        "ms" => Ok(val as f64 / 1000.0 / 1000.0),
+        "sec" => Ok(val as f64 / 1000.0 / 1000.0 / 1000.0),
+        "min" => Ok(val as f64 / 1000.0 / 1000.0 / 1000.0 / 60.0),
+        "hr" => Ok(val as f64 / 1000.0 / 1000.0 / 1000.0 / 60.0 / 60.0),
+        "day" => Ok(val as f64 / 1000.0 / 1000.0 / 1000.0 / 60.0 / 60.0 / 24.0),
+        "wk" => Ok(val as f64 / 1000.0 / 1000.0 / 1000.0 / 60.0 / 60.0 / 24.0 / 7.0),
+        "month" => Ok(val as f64 / 1000.0 / 1000.0 / 1000.0 / 60.0 / 60.0 / 24.0 / 30.0),
+        "yr" => Ok(val as f64 / 1000.0 / 1000.0 / 1000.0 / 60.0 / 60.0 / 24.0 / 365.0),
+        "dec" => Ok(val as f64 / 10.0 / 1000.0 / 1000.0 / 1000.0 / 60.0 / 60.0 / 24.0 / 365.0),
+
+        _ => Err(ShellError::CantConvertToDuration {
+            details: to_unit.to_string(),
+            dst_span: span,
+            src_span: value_span,
+            help: Some(
+                "supported units are ns, us/µs, ms, sec, min, hr, day, wk, month, yr, and dec"
+                    .to_string(),
+            ),
+        }),
+    }
+}
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_examples() {
+        use crate::test_examples;
+
+        test_examples(FormatDuration)
+    }
+}

crates/nu-cmd-extra/src/extra/strings/format/mod.rs

@@ -1,5 +1,7 @@
 mod command;
+mod duration;
 mod filesize;
 
 pub(crate) use command::Format;
+pub(crate) use duration::FormatDuration;
 pub(crate) use filesize::FileSize;

crates/nu-command/src/conversions/into/duration.rs

@@ -3,8 +3,7 @@ use nu_parser::{parse_unit_value, DURATION_UNIT_GROUPS};
 use nu_protocol::{
     ast::{Call, CellPath, Expr},
     engine::{Command, EngineState, Stack},
-    Category, Example, PipelineData, ShellError, Signature, Span, Spanned, SyntaxShape, Type, Unit,
+    Category, Example, PipelineData, ShellError, Signature, Span, SyntaxShape, Type, Unit, Value,
-    Value,
 };
 
 #[derive(Clone)]
@@ -20,19 +19,10 @@ impl Command for SubCommand {
             .input_output_types(vec![
                 (Type::String, Type::Duration),
                 (Type::Duration, Type::Duration),
-                // TODO: --convert option should be implemented as `format duration`
-                (Type::String, Type::String),
-                (Type::Duration, Type::String),
                 (Type::Table(vec![]), Type::Table(vec![])),
                 (Type::Record(vec![]), Type::Record(vec![])),
             ])
             .allow_variants_without_examples(true)
-            .named(
-                "convert",
-                SyntaxShape::String,
-                "convert duration into another duration",
-                Some('c'),
-            )
             .rest(
                 "rest",
                 SyntaxShape::CellPath,
@@ -124,14 +114,6 @@ impl Command for SubCommand {
                     span,
                 }),
             },
-            Example {
-                description: "Convert string to the requested duration as a string",
-                example: "'7min' | into duration --convert sec",
-                result: Some(Value::String {
-                    val: "420 sec".to_string(),
-                    span,
-                }),
-            },
             Example {
                 description: "Convert duration to duration",
                 example: "420sec | into duration",
@@ -140,38 +122,6 @@ impl Command for SubCommand {
                     span,
                 }),
             },
-            Example {
-                description: "Convert duration to the requested duration as a string",
-                example: "420sec | into duration --convert ms",
-                result: Some(Value::String {
-                    val: "420000 ms".to_string(),
-                    span,
-                }),
-            },
-            Example {
-                description: "Convert µs duration to the requested duration as a string",
-                example: "1000000µs | into duration --convert sec",
-                result: Some(Value::String {
-                    val: "1 sec".to_string(),
-                    span,
-                }),
-            },
-            Example {
-                description: "Convert duration to the µs duration as a string",
-                example: "1sec | into duration --convert µs",
-                result: Some(Value::String {
-                    val: "1000000 µs".to_string(),
-                    span,
-                }),
-            },
-            Example {
-                description: "Convert duration to µs as a string if unit asked for was us",
-                example: "1sec | into duration --convert us",
-                result: Some(Value::String {
-                    val: "1000000 µs".to_string(),
-                    span,
-                }),
-            },
         ]
     }
 }
@@ -186,23 +136,17 @@ fn into_duration(
         Some(t) => t,
         None => call.head,
     };
-    let convert_to_unit: Option<Spanned<String>> = call.get_flag(engine_state, stack, "convert")?;
     let column_paths: Vec<CellPath> = call.rest(engine_state, stack, 0)?;
-    let config = engine_state.get_config();
-    let float_precision = config.float_precision as usize;
 
     input.map(
         move |v| {
             if column_paths.is_empty() {
-                action(&v, &convert_to_unit, float_precision, span)
+                action(&v, span)
             } else {
                 let mut ret = v;
                 for path in &column_paths {
-                    let d = convert_to_unit.clone();
+                    let r =
-                    let r = ret.update_cell_path(
+                        ret.update_cell_path(&path.members, Box::new(move |old| action(old, span)));
-                        &path.members,
-                        Box::new(move |old| action(old, &d, float_precision, span)),
-                    );
                     if let Err(error) = r {
                         return Value::Error {
                             error: Box::new(error),
@@ -217,198 +161,6 @@ fn into_duration(
     )
 }
 
-fn convert_str_from_unit_to_unit(
-    val: i64,
-    from_unit: &str,
-    to_unit: &str,
-    span: Span,
-    value_span: Span,
-) -> Result<f64, ShellError> {
-    match (from_unit, to_unit) {
-        ("ns", "ns") => Ok(val as f64),
-        ("ns", "us") => Ok(val as f64 / 1000.0),
-        ("ns", "µs") => Ok(val as f64 / 1000.0), // Micro sign
-        ("ns", "μs") => Ok(val as f64 / 1000.0), // Greek small letter
-        ("ns", "ms") => Ok(val as f64 / 1000.0 / 1000.0),
-        ("ns", "sec") => Ok(val as f64 / 1000.0 / 1000.0 / 1000.0),
-        ("ns", "min") => Ok(val as f64 / 1000.0 / 1000.0 / 1000.0 / 60.0),
-        ("ns", "hr") => Ok(val as f64 / 1000.0 / 1000.0 / 1000.0 / 60.0 / 60.0),
-        ("ns", "day") => Ok(val as f64 / 1000.0 / 1000.0 / 1000.0 / 60.0 / 60.0 / 24.0),
-        ("ns", "wk") => Ok(val as f64 / 1000.0 / 1000.0 / 1000.0 / 60.0 / 60.0 / 24.0 / 7.0),
-        ("ns", "month") => Ok(val as f64 / 1000.0 / 1000.0 / 1000.0 / 60.0 / 60.0 / 24.0 / 30.0),
-        ("ns", "yr") => Ok(val as f64 / 1000.0 / 1000.0 / 1000.0 / 60.0 / 60.0 / 24.0 / 365.0),
-        ("ns", "dec") => {
-            Ok(val as f64 / 10.0 / 1000.0 / 1000.0 / 1000.0 / 60.0 / 60.0 / 24.0 / 365.0)
-        }
-
-        ("us", "ns") => Ok(val as f64 * 1000.0),
-        ("us", "us") => Ok(val as f64),
-        ("us", "µs") => Ok(val as f64), // Micro sign
-        ("us", "μs") => Ok(val as f64), // Greek small letter
-        ("us", "ms") => Ok(val as f64 / 1000.0),
-        ("us", "sec") => Ok(val as f64 / 1000.0 / 1000.0),
-        ("us", "min") => Ok(val as f64 / 1000.0 / 1000.0 / 60.0),
-        ("us", "hr") => Ok(val as f64 / 1000.0 / 1000.0 / 60.0 / 60.0),
-        ("us", "day") => Ok(val as f64 / 1000.0 / 1000.0 / 60.0 / 60.0 / 24.0),
-        ("us", "wk") => Ok(val as f64 / 1000.0 / 1000.0 / 60.0 / 60.0 / 24.0 / 7.0),
-        ("us", "month") => Ok(val as f64 / 1000.0 / 1000.0 / 60.0 / 60.0 / 24.0 / 30.0),
-        ("us", "yr") => Ok(val as f64 / 1000.0 / 1000.0 / 60.0 / 60.0 / 24.0 / 365.0),
-        ("us", "dec") => Ok(val as f64 / 10.0 / 1000.0 / 1000.0 / 60.0 / 60.0 / 24.0 / 365.0),
-
-        // Micro sign
-        ("µs", "ns") => Ok(val as f64 * 1000.0),
-        ("µs", "us") => Ok(val as f64),
-        ("µs", "µs") => Ok(val as f64), // Micro sign
-        ("µs", "μs") => Ok(val as f64), // Greek small letter
-        ("µs", "ms") => Ok(val as f64 / 1000.0),
-        ("µs", "sec") => Ok(val as f64 / 1000.0 / 1000.0),
-        ("µs", "min") => Ok(val as f64 / 1000.0 / 1000.0 / 60.0),
-        ("µs", "hr") => Ok(val as f64 / 1000.0 / 1000.0 / 60.0 / 60.0),
-        ("µs", "day") => Ok(val as f64 / 1000.0 / 1000.0 / 60.0 / 60.0 / 24.0),
-        ("µs", "wk") => Ok(val as f64 / 1000.0 / 1000.0 / 60.0 / 60.0 / 24.0 / 7.0),
-        ("µs", "month") => Ok(val as f64 / 1000.0 / 1000.0 / 60.0 / 60.0 / 24.0 / 30.0),
-        ("µs", "yr") => Ok(val as f64 / 1000.0 / 1000.0 / 60.0 / 60.0 / 24.0 / 365.0),
-        ("µs", "dec") => Ok(val as f64 / 10.0 / 1000.0 / 1000.0 / 60.0 / 60.0 / 24.0 / 365.0),
-
-        // Greek small letter
-        ("μs", "ns") => Ok(val as f64 * 1000.0),
-        ("μs", "us") => Ok(val as f64),
-        ("μs", "µs") => Ok(val as f64), // Micro sign
-        ("μs", "μs") => Ok(val as f64), // Greek small letter
-        ("μs", "ms") => Ok(val as f64 / 1000.0),
-        ("μs", "sec") => Ok(val as f64 / 1000.0 / 1000.0),
-        ("μs", "min") => Ok(val as f64 / 1000.0 / 1000.0 / 60.0),
-        ("μs", "hr") => Ok(val as f64 / 1000.0 / 1000.0 / 60.0 / 60.0),
-        ("μs", "day") => Ok(val as f64 / 1000.0 / 1000.0 / 60.0 / 60.0 / 24.0),
-        ("μs", "wk") => Ok(val as f64 / 1000.0 / 1000.0 / 60.0 / 60.0 / 24.0 / 7.0),
-        ("μs", "month") => Ok(val as f64 / 1000.0 / 1000.0 / 60.0 / 60.0 / 24.0 / 30.0),
-        ("μs", "yr") => Ok(val as f64 / 1000.0 / 1000.0 / 60.0 / 60.0 / 24.0 / 365.0),
-        ("μs", "dec") => Ok(val as f64 / 10.0 / 1000.0 / 1000.0 / 60.0 / 60.0 / 24.0 / 365.0),
-
-        ("ms", "ns") => Ok(val as f64 * 1000.0 * 1000.0),
-        ("ms", "us") => Ok(val as f64 * 1000.0),
-        ("ms", "µs") => Ok(val as f64 * 1000.0), // Micro sign
-        ("ms", "μs") => Ok(val as f64 * 1000.0), // Greek small letter
-        ("ms", "ms") => Ok(val as f64),
-        ("ms", "sec") => Ok(val as f64 / 1000.0),
-        ("ms", "min") => Ok(val as f64 / 1000.0 / 60.0),
-        ("ms", "hr") => Ok(val as f64 / 1000.0 / 60.0 / 60.0),
-        ("ms", "day") => Ok(val as f64 / 1000.0 / 60.0 / 60.0 / 24.0),
-        ("ms", "wk") => Ok(val as f64 / 1000.0 / 60.0 / 60.0 / 24.0 / 7.0),
-        ("ms", "month") => Ok(val as f64 / 1000.0 / 60.0 / 60.0 / 24.0 / 30.0),
-        ("ms", "yr") => Ok(val as f64 / 1000.0 / 60.0 / 60.0 / 24.0 / 365.0),
-        ("ms", "dec") => Ok(val as f64 / 10.0 / 1000.0 / 60.0 / 60.0 / 24.0 / 365.0),
-
-        ("sec", "ns") => Ok(val as f64 * 1000.0 * 1000.0 * 1000.0),
-        ("sec", "us") => Ok(val as f64 * 1000.0 * 1000.0),
-        ("sec", "µs") => Ok(val as f64 * 1000.0 * 1000.0), // Micro sign
-        ("sec", "μs") => Ok(val as f64 * 1000.0 * 1000.0), // Greek small letter
-        ("sec", "ms") => Ok(val as f64 * 1000.0),
-        ("sec", "sec") => Ok(val as f64),
-        ("sec", "min") => Ok(val as f64 / 60.0),
-        ("sec", "hr") => Ok(val as f64 / 60.0 / 60.0),
-        ("sec", "day") => Ok(val as f64 / 60.0 / 60.0 / 24.0),
-        ("sec", "wk") => Ok(val as f64 / 60.0 / 60.0 / 24.0 / 7.0),
-        ("sec", "month") => Ok(val as f64 / 60.0 / 60.0 / 24.0 / 30.0),
-        ("sec", "yr") => Ok(val as f64 / 60.0 / 60.0 / 24.0 / 365.0),
-        ("sec", "dec") => Ok(val as f64 / 10.0 / 60.0 / 60.0 / 24.0 / 365.0),
-
-        ("min", "ns") => Ok(val as f64 * 1000.0 * 1000.0 * 1000.0 * 60.0),
-        ("min", "us") => Ok(val as f64 * 1000.0 * 1000.0 * 60.0),
-        ("min", "µs") => Ok(val as f64 * 1000.0 * 1000.0 * 60.0), // Micro sign
-        ("min", "μs") => Ok(val as f64 * 1000.0 * 1000.0 * 60.0), // Greek small letter
-        ("min", "ms") => Ok(val as f64 * 1000.0 * 60.0),
-        ("min", "sec") => Ok(val as f64 * 60.0),
-        ("min", "min") => Ok(val as f64),
-        ("min", "hr") => Ok(val as f64 / 60.0),
-        ("min", "day") => Ok(val as f64 / 60.0 / 24.0),
-        ("min", "wk") => Ok(val as f64 / 60.0 / 24.0 / 7.0),
-        ("min", "month") => Ok(val as f64 / 60.0 / 24.0 / 30.0),
-        ("min", "yr") => Ok(val as f64 / 60.0 / 24.0 / 365.0),
-        ("min", "dec") => Ok(val as f64 / 10.0 / 60.0 / 24.0 / 365.0),
-
-        ("hr", "ns") => Ok(val as f64 * 1000.0 * 1000.0 * 1000.0 * 60.0 * 60.0),
-        ("hr", "us") => Ok(val as f64 * 1000.0 * 1000.0 * 60.0 * 60.0),
-        ("hr", "µs") => Ok(val as f64 * 1000.0 * 1000.0 * 60.0 * 60.0), // Micro sign
-        ("hr", "μs") => Ok(val as f64 * 1000.0 * 1000.0 * 60.0 * 60.0), // Greek small letter
-        ("hr", "ms") => Ok(val as f64 * 1000.0 * 60.0 * 60.0),
-        ("hr", "sec") => Ok(val as f64 * 60.0 * 60.0),
-        ("hr", "min") => Ok(val as f64 * 60.0),
-        ("hr", "hr") => Ok(val as f64),
-        ("hr", "day") => Ok(val as f64 / 24.0),
-        ("hr", "wk") => Ok(val as f64 / 24.0 / 7.0),
-        ("hr", "month") => Ok(val as f64 / 24.0 / 30.0),
-        ("hr", "yr") => Ok(val as f64 / 24.0 / 365.0),
-        ("hr", "dec") => Ok(val as f64 / 10.0 / 24.0 / 365.0),
-
-        ("day", "ns") => Ok(val as f64 * 1000.0 * 1000.0 * 1000.0 * 60.0 * 60.0 * 24.0),
-        ("day", "us") => Ok(val as f64 * 1000.0 * 1000.0 * 60.0 * 60.0 * 24.0),
-        ("day", "µs") => Ok(val as f64 * 1000.0 * 1000.0 * 60.0 * 60.0 * 24.0), // Micro sign
-        ("day", "μs") => Ok(val as f64 * 1000.0 * 1000.0 * 60.0 * 60.0 * 24.0), // Greek small letter
-        ("day", "ms") => Ok(val as f64 * 1000.0 * 60.0 * 60.0 * 24.0),
-        ("day", "sec") => Ok(val as f64 * 60.0 * 60.0 * 24.0),
-        ("day", "min") => Ok(val as f64 * 60.0 * 24.0),
-        ("day", "hr") => Ok(val as f64 * 24.0),
-        ("day", "day") => Ok(val as f64),
-        ("day", "wk") => Ok(val as f64 / 7.0),
-        ("day", "month") => Ok(val as f64 / 30.0),
-        ("day", "yr") => Ok(val as f64 / 365.0),
-        ("day", "dec") => Ok(val as f64 / 10.0 / 365.0),
-
-        ("wk", "ns") => Ok(val as f64 * 1000.0 * 1000.0 * 1000.0 * 60.0 * 60.0 * 24.0 * 7.0),
-        ("wk", "us") => Ok(val as f64 * 1000.0 * 1000.0 * 60.0 * 60.0 * 24.0 * 7.0),
-        ("wk", "µs") => Ok(val as f64 * 1000.0 * 1000.0 * 60.0 * 60.0 * 24.0 * 7.0), // Micro sign
-        ("wk", "μs") => Ok(val as f64 * 1000.0 * 1000.0 * 60.0 * 60.0 * 24.0 * 7.0), // Greek small letter
-        ("wk", "ms") => Ok(val as f64 * 1000.0 * 60.0 * 60.0 * 24.0 * 7.0),
-        ("wk", "sec") => Ok(val as f64 * 60.0 * 60.0 * 24.0 * 7.0),
-        ("wk", "min") => Ok(val as f64 * 60.0 * 24.0 * 7.0),
-        ("wk", "hr") => Ok(val as f64 * 24.0 * 7.0),
-        ("wk", "day") => Ok(val as f64 * 7.0),
-        ("wk", "wk") => Ok(val as f64),
-        ("wk", "month") => Ok(val as f64 / 4.0),
-        ("wk", "yr") => Ok(val as f64 / 52.0),
-        ("wk", "dec") => Ok(val as f64 / 10.0 / 52.0),
-
-        ("month", "ns") => Ok(val as f64 * 1000.0 * 1000.0 * 1000.0 * 60.0 * 60.0 * 24.0 * 30.0),
-        ("month", "us") => Ok(val as f64 * 1000.0 * 1000.0 * 60.0 * 60.0 * 24.0 * 30.0),
-        ("month", "µs") => Ok(val as f64 * 1000.0 * 1000.0 * 60.0 * 60.0 * 24.0 * 30.0), // Micro sign
-        ("month", "μs") => Ok(val as f64 * 1000.0 * 1000.0 * 60.0 * 60.0 * 24.0 * 30.0), // Greek small letter
-        ("month", "ms") => Ok(val as f64 * 1000.0 * 60.0 * 60.0 * 24.0 * 30.0),
-        ("month", "sec") => Ok(val as f64 * 60.0 * 60.0 * 24.0 * 30.0),
-        ("month", "min") => Ok(val as f64 * 60.0 * 24.0 * 30.0),
-        ("month", "hr") => Ok(val as f64 * 24.0 * 30.0),
-        ("month", "day") => Ok(val as f64 * 30.0),
-        ("month", "wk") => Ok(val as f64 * 4.0),
-        ("month", "month") => Ok(val as f64),
-        ("month", "yr") => Ok(val as f64 / 12.0),
-        ("month", "dec") => Ok(val as f64 / 10.0 / 12.0),
-
-        ("yr", "ns") => Ok(val as f64 * 1000.0 * 1000.0 * 1000.0 * 60.0 * 60.0 * 24.0 * 365.0),
-        ("yr", "us") => Ok(val as f64 * 1000.0 * 1000.0 * 60.0 * 60.0 * 24.0 * 365.0),
-        ("yr", "µs") => Ok(val as f64 * 1000.0 * 1000.0 * 60.0 * 60.0 * 24.0 * 365.0), // Micro sign
-        ("yr", "μs") => Ok(val as f64 * 1000.0 * 1000.0 * 60.0 * 60.0 * 24.0 * 365.0), // Greek small letter
-        ("yr", "ms") => Ok(val as f64 * 1000.0 * 60.0 * 60.0 * 24.0 * 365.0),
-        ("yr", "sec") => Ok(val as f64 * 60.0 * 60.0 * 24.0 * 365.0),
-        ("yr", "min") => Ok(val as f64 * 60.0 * 24.0 * 365.0),
-        ("yr", "hr") => Ok(val as f64 * 24.0 * 365.0),
-        ("yr", "day") => Ok(val as f64 * 365.0),
-        ("yr", "wk") => Ok(val as f64 * 52.0),
-        ("yr", "month") => Ok(val as f64 * 12.0),
-        ("yr", "yr") => Ok(val as f64),
-        ("yr", "dec") => Ok(val as f64 / 10.0),
-
-        _ => Err(ShellError::CantConvertToDuration {
-            details: to_unit.to_string(),
-            dst_span: span,
-            src_span: value_span,
-            help: Some(
-                "supported units are ns, us/µs, ms, sec, min, hr, day, wk, month, yr, and dec"
-                    .to_string(),
-            ),
-        }),
-    }
-}
-
 fn string_to_duration(s: &str, span: Span, value_span: Span) -> Result<i64, ShellError> {
     if let Some(Ok(expression)) = parse_unit_value(
         s.as_bytes(),
@@ -445,146 +197,18 @@ fn string_to_duration(s: &str, span: Span, value_span: Span) -> Result<i64, Shel
     })
 }
 
-fn string_to_unit_duration(
+fn action(input: &Value, span: Span) -> Value {
-    s: &str,
-    span: Span,
-    value_span: Span,
-) -> Result<(&str, i64), ShellError> {
-    if let Some(Ok(expression)) = parse_unit_value(
-        s.as_bytes(),
-        span,
-        DURATION_UNIT_GROUPS,
-        Type::Duration,
-        |x| x,
-    ) {
-        if let Expr::ValueWithUnit(value, unit) = expression.expr {
-            if let Expr::Int(x) = value.expr {
-                match unit.item {
-                    Unit::Nanosecond => return Ok(("ns", x)),
-                    Unit::Microsecond => return Ok(("µs", x)),
-                    Unit::Millisecond => return Ok(("ms", x)),
-                    Unit::Second => return Ok(("sec", x)),
-                    Unit::Minute => return Ok(("min", x)),
-                    Unit::Hour => return Ok(("hr", x)),
-                    Unit::Day => return Ok(("day", x)),
-                    Unit::Week => return Ok(("wk", x)),
-
-                    _ => return Ok(("ns", 0)),
-                }
-            }
-        }
-    }
-
-    Err(ShellError::CantConvertToDuration {
-        details: s.to_string(),
-        dst_span: span,
-        src_span: value_span,
-        help: Some(
-            "supported units are ns, us/µs, ms, sec, min, hr, day, wk, month, yr, and dec"
-                .to_string(),
-        ),
-    })
-}
-
-fn action(
-    input: &Value,
-    convert_to_unit: &Option<Spanned<String>>,
-    float_precision: usize,
-    span: Span,
-) -> Value {
     match input {
-        Value::Duration {
+        Value::Duration { .. } => input.clone(),
-            val: val_num,
-            span: value_span,
-        } => {
-            if let Some(to_unit) = convert_to_unit {
-                let from_unit = "ns";
-                let duration = *val_num;
-                match convert_str_from_unit_to_unit(
-                    duration,
-                    from_unit,
-                    &to_unit.item,
-                    span,
-                    *value_span,
-                ) {
-                    Ok(d) => {
-                        let unit = if &to_unit.item == "us" {
-                            "µs"
-                        } else {
-                            &to_unit.item
-                        };
-                        if d.fract() == 0.0 {
-                            Value::String {
-                                val: format!("{} {}", d, unit),
-                                span: *value_span,
-                            }
-                        } else {
-                            Value::String {
-                                val: format!("{:.float_precision$} {}", d, unit),
-                                span: *value_span,
-                            }
-                        }
-                    }
-                    Err(e) => Value::Error { error: Box::new(e) },
-                }
-            } else {
-                input.clone()
-            }
-        }
         Value::String {
             val,
             span: value_span,
-        } => {
+        } => match string_to_duration(val, span, *value_span) {
-            if let Some(to_unit) = convert_to_unit {
+            Ok(val) => Value::Duration { val, span },
-                if let Ok(dur) = string_to_unit_duration(val, span, *value_span) {
+            Err(error) => Value::Error {
-                    let from_unit = dur.0;
+                error: Box::new(error),
-                    let duration = dur.1;
+            },
-                    match convert_str_from_unit_to_unit(
+        },
-                        duration,
-                        from_unit,
-                        &to_unit.item,
-                        span,
-                        *value_span,
-                    ) {
-                        Ok(d) => {
-                            let unit = if &to_unit.item == "us" {
-                                "µs"
-                            } else {
-                                &to_unit.item
-                            };
-                            if d.fract() == 0.0 {
-                                Value::String {
-                                    val: format!("{} {}", d, unit),
-                                    span: *value_span,
-                                }
-                            } else {
-                                Value::String {
-                                    val: format!("{:.float_precision$} {}", d, unit),
-                                    span: *value_span,
-                                }
-                            }
-                        }
-                        Err(e) => Value::Error { error: Box::new(e) },
-                    }
-                } else {
-                    Value::Error {
-                        error: Box::new(ShellError::CantConvert {
-                            to_type: "string".into(),
-                            from_type: "duration".into(),
-                            span,
-                            help: None,
-                        }),
-                    }
-                }
-            } else {
-                match string_to_duration(val, span, *value_span) {
-                    Ok(val) => Value::Duration { val, span },
-                    Err(error) => Value::Error {
-                        error: Box::new(error),
-                    },
-                }
-            }
-        }
         // Propagate errors by explicitly matching them before the final case.
         Value::Error { .. } => input.clone(),
         other => Value::Error {
@@ -614,9 +238,8 @@ mod test {
         let span = Span::new(0, 2);
         let word = Value::test_string("3ns");
         let expected = Value::Duration { val: 3, span };
-        let convert_duration = None;
 
-        let actual = action(&word, &convert_duration, 2, span);
+        let actual = action(&word, span);
         assert_eq!(actual, expected);
     }
 
@@ -628,9 +251,8 @@ mod test {
             val: 4 * 1000,
             span,
         };
-        let convert_duration = None;
 
-        let actual = action(&word, &convert_duration, 2, span);
+        let actual = action(&word, span);
         assert_eq!(actual, expected);
     }
 
@@ -642,9 +264,8 @@ mod test {
             val: 4 * 1000,
             span,
         };
-        let convert_duration = None;
 
-        let actual = action(&word, &convert_duration, 2, span);
+        let actual = action(&word, span);
         assert_eq!(actual, expected);
     }
 
@@ -656,9 +277,8 @@ mod test {
             val: 4 * 1000,
             span,
         };
-        let convert_duration = None;
 
-        let actual = action(&word, &convert_duration, 2, span);
+        let actual = action(&word, span);
         assert_eq!(actual, expected);
     }
 
@@ -670,9 +290,8 @@ mod test {
             val: 5 * 1000 * 1000,
             span,
         };
-        let convert_duration = None;
 
-        let actual = action(&word, &convert_duration, 2, span);
+        let actual = action(&word, span);
         assert_eq!(actual, expected);
     }
 
@@ -684,9 +303,8 @@ mod test {
             val: 1000 * 1000 * 1000,
             span,
         };
-        let convert_duration = None;
 
-        let actual = action(&word, &convert_duration, 2, span);
+        let actual = action(&word, span);
         assert_eq!(actual, expected);
     }
 
@@ -698,9 +316,8 @@ mod test {
             val: 7 * 60 * 1000 * 1000 * 1000,
             span,
         };
-        let convert_duration = None;
 
-        let actual = action(&word, &convert_duration, 2, span);
+        let actual = action(&word, span);
         assert_eq!(actual, expected);
     }
 
@@ -712,9 +329,8 @@ mod test {
             val: 42 * 60 * 60 * 1000 * 1000 * 1000,
             span,
         };
-        let convert_duration = None;
 
-        let actual = action(&word, &convert_duration, 2, span);
+        let actual = action(&word, span);
         assert_eq!(actual, expected);
     }
 
@@ -726,9 +342,8 @@ mod test {
             val: 123 * 24 * 60 * 60 * 1000 * 1000 * 1000,
             span,
         };
-        let convert_duration = None;
 
-        let actual = action(&word, &convert_duration, 2, span);
+        let actual = action(&word, span);
         assert_eq!(actual, expected);
     }
 
@@ -740,9 +355,8 @@ mod test {
             val: 3 * 7 * 24 * 60 * 60 * 1000 * 1000 * 1000,
             span,
         };
-        let convert_duration = None;
 
-        let actual = action(&word, &convert_duration, 2, span);
+        let actual = action(&word, span);
         assert_eq!(actual, expected);
     }
 }