Correct handling of non-numeric chars in parse_buf

Without this fix, int::parse_buf and uint::parse_buf return incorrect results
for any strings that contain non-numeric characters.  Fixes rust-lang#1102.

Author: mbrubeck

src/lib/int.rs

@@ -112,7 +112,15 @@ fn parse_buf(buf: [u8], radix: uint) -> int {
     }
     let n = 0;
     while true {
-        n += (buf[i] - ('0' as u8) as int) * power;
+        let digit = alt buf[i] as char {
+            '0' to '9' { buf[i] - ('0' as u8) }
+            'a' to 'z' { 10u8 + buf[i] - ('a' as u8) }
+            'A' to 'Z' { 10u8 + buf[i] - ('A' as u8) }
+        };
+        if (digit as uint) >= radix {
+            fail;
+        }
+        n += (digit as int) * power;
         power *= radix as int;
         if i <= start { ret n; }
         i -= 1u;

src/lib/uint.rs

@@ -100,7 +100,15 @@ fn parse_buf(buf: [u8], radix: uint) -> uint {
     let power = 1u;
     let n = 0u;
     while true {
-        n += (buf[i] - ('0' as u8) as uint) * power;
+        let digit = alt buf[i] as char {
+            '0' to '9' { buf[i] - ('0' as u8) }
+            'a' to 'z' { 10u8 + buf[i] - ('a' as u8) }
+            'A' to 'Z' { 10u8 + buf[i] - ('A' as u8) }
+        };
+        if (digit as uint) >= radix {
+            fail;
+        }
+        n += (digit as uint) * power;
         power *= radix;
         if i == 0u { ret n; }
         i -= 1u;

src/test/stdtest/int.rs

@@ -2,6 +2,7 @@
 use std;
 import std::int;
 import std::str::eq;
+import std::str::bytes;
 
 #[test]
 fn test_from_str() {
@@ -18,6 +19,27 @@ fn test_from_str() {
     assert(int::from_str("-00100") == -100);
 }
 
+#[test]
+fn test_parse_buf() {
+    assert (int::parse_buf(bytes("123"), 10u) == 123);
+    assert (int::parse_buf(bytes("1001"), 2u) == 9);
+    assert (int::parse_buf(bytes("123"), 8u) == 83);
+    assert (int::parse_buf(bytes("123"), 16u) == 291);
+    assert (int::parse_buf(bytes("ffff"), 16u) == 65535);
+    assert (int::parse_buf(bytes("FFFF"), 16u) == 65535);
+    assert (int::parse_buf(bytes("z"), 36u) == 35);
+    assert (int::parse_buf(bytes("Z"), 36u) == 35);
+
+    assert (int::parse_buf(bytes("-123"), 10u) == -123);
+    assert (int::parse_buf(bytes("-1001"), 2u) == -9);
+    assert (int::parse_buf(bytes("-123"), 8u) == -83);
+    assert (int::parse_buf(bytes("-123"), 16u) == -291);
+    assert (int::parse_buf(bytes("-ffff"), 16u) == -65535);
+    assert (int::parse_buf(bytes("-FFFF"), 16u) == -65535);
+    assert (int::parse_buf(bytes("-z"), 36u) == -35);
+    assert (int::parse_buf(bytes("-Z"), 36u) == -35);
+}
+
 #[test]
 fn test_to_str() {
     assert (eq(int::to_str(0, 10u), "0"));

src/test/stdtest/uint.rs

@@ -3,6 +3,26 @@
 // -*- rust -*-
 use std;
 import std::uint;
+import std::str::bytes;
+
+#[test]
+fn test_from_str() {
+    assert (uint::from_str("0") == 0u);
+    assert (uint::from_str("3") == 3u);
+    assert (uint::from_str("10") == 10u);
+    assert (uint::from_str("123456789") == 123456789u);
+    assert (uint::from_str("00100") == 100u);
+}
+
+#[test]
+fn test_parse_buf() {
+    assert (uint::parse_buf(bytes("123"), 10u) == 123u);
+    assert (uint::parse_buf(bytes("1001"), 2u) == 9u);
+    assert (uint::parse_buf(bytes("123"), 8u) == 83u);
+    assert (uint::parse_buf(bytes("123"), 16u) == 291u);
+    assert (uint::parse_buf(bytes("ffff"), 16u) == 65535u);
+    assert (uint::parse_buf(bytes("z"), 36u) == 35u);
+}
 
 #[test]
 fn test_next_power_of_two() {
@@ -53,4 +73,4 @@ fn test_overflows() {
    assert (uint::max_value() > 0u);
    assert (uint::min_value() <= 0u);
    assert (uint::min_value() + uint::max_value() + 1u == 0u);
-}
+}