Tweaked convert() api, added comments

src/unit.rs

@@ -34,19 +34,22 @@ impl Unit {
             "blk" | "blks"
             | "blck" |"blcks"
             | "block" | "blocks" => Ok(Self::Blocks),
-            _ => Err(s),
+            _ => Err("use --help to get a list of units".into()),
         }
     }
 
     pub fn convert(self, n: u64) -> String {
-        let n = if self == Self::Blocks {
-            n.next_multiple_of(self.integer_value())
-        } else {
-            n
-        };
-        format!("{}{}", n/self.integer_value(), self.units_pretty())
+        format!("{}", n/self.integer_value())
+    }
+    
+    pub fn convert_with_units(self, n: u64) -> String {
+        self.convert(n) + self.units_pretty()
     }
 
+    /// Units to print for each different unit.
+    /// They all have a space between at the front
+    /// for style reasons, except for bytes which are
+    /// basically unindicated
     const fn units_pretty(self) -> &'static str {
         match self {
             Self::Byte => "",
@@ -62,9 +65,16 @@ impl Unit {
         }
     }
 
+    /// The size is always held in bytes, so
+    /// this returns the scale factor.
+    /// A special case is made for
+    /// blocks, because the number of blocks
+    /// is repeatedly queried throughout
+    /// the search process, it needn't be
+    /// altered here
     const fn integer_value(self) -> u64 {
         match self {
-            Self::Byte => 1,
+            Self::Byte | Self::Blocks => 1,
             Self::Kilo => 1_000,
             Self::Kibi => 1_024,
             Self::Mega => 1_000_000,
@@ -73,7 +83,6 @@ impl Unit {
             Self::Gibi => 1_073_741_824,
             Self::Tera => 1_000_000_000_000,
             Self::Tibi => 1_099_511_627_776,
-            Self::Blocks => 512,
         }
     }
 }