Add filesize.show_unit config option (#15276)

# Description

Continuation of #15271. This PR adds the
`$env.config.filesize.show_unit` option to allow the ability to omit the
filesize unit. Useful if `$env.config.filesize.unit` is set to a fixed
unit, and you don't want the same unit repeated over and over.

# User-Facing Changes

- Adds the `$env.config.filesize.show_unit` option.

crates/nu-protocol/src/config/filesize.rs

@@ -11,6 +11,7 @@ impl IntoValue for FilesizeUnitFormat {
 #[derive(Clone, Copy, Debug, PartialEq, Eq, Serialize, Deserialize)]
 pub struct FilesizeConfig {
     pub unit: FilesizeUnitFormat,
+    pub show_unit: bool,
     pub precision: Option<usize>,
 }
 
@@ -18,6 +19,7 @@ impl FilesizeConfig {
     pub fn formatter(&self) -> FilesizeFormatter {
         FilesizeFormatter::new()
             .unit(self.unit)
+            .show_unit(self.show_unit)
             .precision(self.precision)
             .locale(get_system_locale()) // TODO: cache this somewhere or pass in as argument
     }
@@ -31,6 +33,7 @@ impl Default for FilesizeConfig {
     fn default() -> Self {
         Self {
             unit: FilesizeUnitFormat::Metric,
+            show_unit: true,
             precision: Some(1),
         }
     }
@@ -67,6 +70,7 @@ impl UpdateFromValue for FilesizeConfig {
                         errors.type_mismatch(path, Type::String, val)
                     }
                 }
+                "show_unit" => self.show_unit.update(val, path, errors),
                 "precision" => match *val {
                     Value::Nothing { .. } => self.precision = None,
                     Value::Int { val, .. } if val >= 0 => self.precision = Some(val as usize),
@@ -83,6 +87,7 @@ impl IntoValue for FilesizeConfig {
     fn into_value(self, span: Span) -> Value {
         record! {
             "unit" => self.unit.into_value(span),
+            "show_unit" => self.show_unit.into_value(span),
             "precision" => self.precision.map(|x| x as i64).into_value(span),
         }
         .into_value(span)

crates/nu-protocol/src/value/filesize.rs

@@ -610,6 +610,7 @@ impl FromStr for FilesizeUnitFormat {
 ///
 /// [`FilesizeFormatter`] is a builder struct that you can modify via the following methods:
 /// - [`unit`](Self::unit)
+/// - [`show_unit`](Self::show_unit)
 /// - [`precision`](Self::precision)
 /// - [`locale`](Self::locale)
 ///
@@ -637,6 +638,7 @@ impl FromStr for FilesizeUnitFormat {
 #[derive(Clone, Copy, Debug, PartialEq, Eq, Hash)]
 pub struct FilesizeFormatter {
     unit: FilesizeUnitFormat,
+    show_unit: bool,
     precision: Option<usize>,
     locale: Locale,
 }
@@ -646,12 +648,14 @@ impl FilesizeFormatter {
     ///
     /// The default formatter has:
     /// - a [`unit`](Self::unit) of [`FilesizeUnitFormat::Metric`].
+    /// - a [`show_unit`](Self::show_unit) of `true`.
     /// - a [`precision`](Self::precision) of `None`.
     /// - a [`locale`](Self::locale) of [`Locale::en_US_POSIX`]
     ///   (a very plain format with no thousands separators).
     pub fn new() -> Self {
         FilesizeFormatter {
             unit: FilesizeUnitFormat::Metric,
+            show_unit: true,
             precision: None,
             locale: Locale::en_US_POSIX,
         }
@@ -682,6 +686,30 @@ impl FilesizeFormatter {
         self
     }
 
+    /// Sets whether to show or omit the file size unit in the formatted output.
+    ///
+    /// This setting can be used to disable the unit formatting from [`FilesizeFormatter`]
+    /// and instead provide your own.
+    ///
+    /// Note that the [`FilesizeUnitFormat`] provided to [`unit`](Self::unit) is still used to
+    /// format the numeric portion of a [`Filesize`]. So, setting `show_unit` to `false` is only
+    /// recommended for [`FilesizeUnitFormat::Unit`], since this will keep the unit the same
+    /// for all [`Filesize`]s. [`FilesizeUnitFormat::Metric`] and [`FilesizeUnitFormat::Binary`],
+    /// on the other hand, will adapt the unit to match the magnitude of each formatted [`Filesize`].
+    ///
+    /// # Examples
+    /// ```
+    /// # use nu_protocol::{Filesize, FilesizeFormatter, FilesizeUnit};
+    /// let filesize = Filesize::from_unit(4, FilesizeUnit::KiB).unwrap();
+    /// let formatter = FilesizeFormatter::new().show_unit(false);
+    ///
+    /// assert_eq!(formatter.unit(FilesizeUnit::B).format(filesize).to_string(), "4096");
+    /// assert_eq!(format!("{} KB", formatter.unit(FilesizeUnit::KiB).format(filesize)), "4 KB");
+    /// ```
+    pub fn show_unit(self, show_unit: bool) -> Self {
+        Self { show_unit, ..self }
+    }
+
     /// Set the number of digits to display after the decimal place.
     ///
     /// Note that digits after the decimal place will never be shown if:
@@ -790,6 +818,7 @@ impl fmt::Display for FormattedFilesize {
         let Self { filesize, format } = *self;
         let FilesizeFormatter {
             unit,
+            show_unit,
             precision,
             locale,
         } = format;
@@ -839,7 +868,10 @@ impl fmt::Display for FormattedFilesize {
             }
         }
 
-        write!(f, " {unit}")?;
+        if show_unit {
+            write!(f, " {unit}")?;
+        }
+
         Ok(())
     }
 }

crates/nu-utils/src/default_files/doc_config.nu

@@ -381,9 +381,14 @@ $env.config.datetime_format.normal = "%m/%d/%y %I:%M:%S%p"
 # Otherwise, setting this to one of the filesize units will use that particular unit when displaying all file sizes.
 $env.config.filesize.unit = 'metric'
 
+# filesize.show_unit (bool):
+# Whether to show or hide the file size unit. Useful if `$env.config.filesize.unit` is set to a fixed unit,
+# and you don't want that same unit repeated over and over again in which case you can set this to `false`.
+$env.config.filesize.show_unit = true
+
 # filesize.precision (int or nothing):
 # The number of digits to display after the decimal point for file sizes.
-# When set to `null`, all digits after the decimal point will be displayed.
+# When set to `null`, all digits after the decimal point, if any, will be displayed.
 $env.config.filesize.precision = 1
 
 # ---------------------

crates/nu-utils/src/locale.rs

@@ -29,6 +29,8 @@ pub fn get_system_locale_string() -> Option<String> {
         },
         #[cfg(test)]
         {
+            // For tests, we use the same locale on all systems.
+            // To override this, set `LOCALE_OVERRIDE_ENV_VAR`.
             || Some(Locale::en_US_POSIX.name().to_owned())
         },
     )