Support #fmt precision for signed types

src/lib/ExtFmt.rs

@@ -332,46 +332,13 @@ mod RT {
                     ty ty);
 
     fn conv_int(&conv cv, int i) -> str {
-        ret pad(cv, _int.to_str(i, 10u));
+        auto radix = 10u;
+        auto prec = get_int_precision(cv);
+        ret pad(cv, int_to_str_prec(i, radix, prec));
     }
 
     fn conv_uint(&conv cv, uint u) -> str {
-
-        // Convert a uint to string with a minimum number of digits.  If
-        // precision is 0 and num is 0 then the result is the empty
-        // string. Could move this to _str, but it doesn't seem all that
-        // useful.
-        fn uint_to_str_prec(uint num, uint radix, uint prec) -> str {
-            auto s;
-
-            if (prec == 0u && num == 0u) {
-                s = "";
-            } else {
-                s = _uint.to_str(num, radix);
-                auto len = _str.char_len(s);
-                if (len < prec) {
-                    auto diff = prec - len;
-                    auto pad = str_init_elt('0', diff);
-                    s = pad + s;
-                }
-            }
-
-            ret s;
-        }
-
-        fn get_precision(&conv cv) -> uint {
-            alt (cv.precision) {
-                case (count_is(?c)) {
-                    ret c as uint;
-                }
-                case (count_implied) {
-                    ret 1u;
-                }
-            }
-        }
-
-        auto prec = get_precision(cv);
-
+        auto prec = get_int_precision(cv);
         auto res;
         alt (cv.ty) {
             case (ty_default) {
@@ -418,6 +385,48 @@ fn conv_str(&conv cv, str s) -> str {
         ret pad(cv, unpadded);
     }
 
+    // Convert an int to string with minimum number of digits. If precision is
+    // 0 and num is 0 then the result is the empty string.
+    fn int_to_str_prec(int num, uint radix, uint prec) -> str {
+        if (num < 0) {
+            ret "-" + uint_to_str_prec((-num) as uint, radix, prec);
+        } else {
+            ret uint_to_str_prec(num as uint, radix, prec);
+        }
+    }
+
+    // Convert a uint to string with a minimum number of digits.  If precision
+    // is 0 and num is 0 then the result is the empty string. Could move this
+    // to _uint, but it doesn't seem all that useful.
+    fn uint_to_str_prec(uint num, uint radix, uint prec) -> str {
+        auto s;
+
+        if (prec == 0u && num == 0u) {
+            s = "";
+        } else {
+            s = _uint.to_str(num, radix);
+            auto len = _str.char_len(s);
+            if (len < prec) {
+                auto diff = prec - len;
+                auto pad = str_init_elt('0', diff);
+                s = pad + s;
+            }
+        }
+
+        ret s;
+    }
+
+    fn get_int_precision(&conv cv) -> uint {
+        alt (cv.precision) {
+            case (count_is(?c)) {
+                ret c as uint;
+            }
+            case (count_implied) {
+                ret 1u;
+            }
+        }
+    }
+
     // FIXME: This might be useful in _str, but needs to be utf8 safe first
     fn str_init_elt(char c, uint n_elts) -> str {
         auto svec = _vec.init_elt[u8](c as u8, n_elts);

src/test/run-pass/syntax-extension-fmt.rs

@@ -55,39 +55,47 @@ fn main() {
   test(#fmt("%-10t", 0xff_u), "11111111  ");
 
   // Precision
-//   test(#fmt("%.d", 0), "");
+   test(#fmt("%.d", 0), "");
    test(#fmt("%.u", 0u), "");
    test(#fmt("%.x", 0u), "");
-//   test(#fmt("%.d", 10), "10");
-//   test(#fmt("%.d", -10), "-10");
+   test(#fmt("%.t", 0u), "");
+   test(#fmt("%.d", 10), "10");
+   test(#fmt("%.d", -10), "-10");
    test(#fmt("%.u", 10u), "10");
    test(#fmt("%.s", "test"), "");
    test(#fmt("%.x", 127u), "7f");
+   test(#fmt("%.t", 3u), "11");
 
-//   test(#fmt("%.0d", 0), "");
+   test(#fmt("%.0d", 0), "");
    test(#fmt("%.0u", 0u), "");
    test(#fmt("%.0x", 0u), "");
-//   test(#fmt("%.0d", 10), "10");
-//   test(#fmt("%.0d", -10), "-10");
+   test(#fmt("%.0t", 0u), "");
+   test(#fmt("%.0d", 10), "10");
+   test(#fmt("%.0d", -10), "-10");
    test(#fmt("%.0u", 10u), "10");
    test(#fmt("%.0s", "test"), "");
    test(#fmt("%.0x", 127u), "7f");
+   test(#fmt("%.0t", 3u), "11");
 
-//   test(#fmt("%.1d", 0), "0");
+   test(#fmt("%.1d", 0), "0");
    test(#fmt("%.1u", 0u), "0");
    test(#fmt("%.1x", 0u), "0");
-//   test(#fmt("%.1d", 10), "10");
-//   test(#fmt("%.1d", -10), "-10");
+   test(#fmt("%.1t", 0u), "0");
+   test(#fmt("%.1d", 10), "10");
+   test(#fmt("%.1d", -10), "-10");
    test(#fmt("%.1u", 10u), "10");
    test(#fmt("%.1s", "test"), "t");
    test(#fmt("%.1x", 127u), "7f");
+   test(#fmt("%.1t", 3u), "11");
 
-//   test(#fmt("%.5d", 0), "00000");
+   test(#fmt("%.5d", 0), "00000");
    test(#fmt("%.5u", 0u), "00000");
    test(#fmt("%.5x", 0u), "00000");
-//   test(#fmt("%.5d", 10), "00010");
-//   test(#fmt("%.5d", -10), "-00010");
+   test(#fmt("%.5t", 0u), "00000");
+   test(#fmt("%.5d", 10), "00010");
+   test(#fmt("%.5d", -10), "-00010");
    test(#fmt("%.5u", 10u), "00010");
    test(#fmt("%.5s", "test"), "test");
    test(#fmt("%.5x", 127u), "0007f");
+   test(#fmt("%.5t", 3u), "00011");
 }