Fix the behaviour -> version 0.2.0

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "leftpad"
-version = "0.1.0"
+version = "0.2.0"
 authors = ["Hubert Figuière <[email protected]>"]
 license = "BSD-2-Clause"
 description = "Pad a string to the left"

NEWS

@@ -0,0 +1,5 @@
+0.2.0
+- actually implement the proper behaviour
+
+0.1.0
+- first release.

src/lib.rs

@@ -2,19 +2,24 @@
 
 
 
-/// pad a string to the left with ``pad`` spaces
-pub fn left_pad(s: &str, pad: u32) -> String
+/// pad a string to the left to ``pad`` length with spaces
+/// If str.len() is less than pad, then the string is returned verbatim
+pub fn left_pad(s: &str, pad: usize) -> String
 {
     left_pad_char(s, pad, ' ')
 }
 
-/// pad a string to the left with ``pad`` ``padchar``
-pub fn left_pad_char(s: &str, pad: u32, padchar: char) -> String
+/// pad a string to the left to ``pad`` length with ``padchar``
+/// If str.len() is less than pad, then the string is returned verbatim
+pub fn left_pad_char(s: &str, pad: usize, padchar: char) -> String
 {
     let mut out = String::new();
 
-    for _ in 0..pad {
-        out.push(padchar);
+    let len = s.len();
+    if pad > len {
+        for _ in 0..pad-len {
+            out.push(padchar);
+        }
     }
     out.push_str(s);
 
@@ -26,9 +31,10 @@ pub fn left_pad_char(s: &str, pad: u32, padchar: char) -> String
 fn pad_test() {
 
     assert_eq!(left_pad("foo", 0), "foo");
+    assert_eq!(left_pad("foo", 2), "foo");
     assert_eq!(left_pad_char("bar", 0, 'Y'), "bar");
-    assert_eq!(left_pad("foo", 2), "  foo");
-    assert_eq!(left_pad_char("foo", 2, 'X'), "XXfoo");
-    assert_eq!(left_pad_char("bar", 5, '-'), "-----bar");
+    assert_eq!(left_pad("foo", 5), "  foo");
+    assert_eq!(left_pad_char("foo", 7, 'X'), "XXXXfoo");
+    assert_eq!(left_pad_char("bar", 5, '-'), "--bar");
 }