seq: fix testsuite failures

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

4 files changed, 66 insertions, 27 deletions

diff --git a/coreutils/seq.c b/coreutils/seq.c
index 4b853c698..bb39a5b54 100644
--- a/coreutils/seq.c
+++ b/coreutils/seq.c
@@ -6,12 +6,10 @@
  *
  * Licensed under the GPL v2, see the file LICENSE in this tarball.
  */
-
 #include "libbb.h"
 
 /* This is a NOFORK applet. Be very careful! */
 
-
 int seq_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int seq_main(int argc, char **argv)
 {
@@ -19,35 +17,72 @@ int seq_main(int argc, char **argv)
                 OPT_w = (1 << 0),
                 OPT_s = (1 << 1),
         };
-        double last, increment, i;
+        double first, last, increment, v;
+        unsigned n;
+        unsigned width;
+        unsigned frac_part;
         const char *sep, *opt_s = "\n";
         unsigned opt = getopt32(argv, "+ws:", &opt_s);
-        unsigned width = 0;
 
         argc -= optind;
         argv += optind;
-        i = increment = 1;
+        first = increment = 1;
+        errno = 0;
         switch (argc) {
+                        char *pp;
                 case 3:
-                        increment = atof(argv[1]);
+                        increment = strtod(argv[1], &pp);
+                        errno |= *pp;
                 case 2:
-                        i = atof(*argv);
+                        first = strtod(argv[0], &pp);
+                        errno |= *pp;
                 case 1:
-                        last = atof(argv[argc-1]);
-                        break;
+                        last = strtod(argv[argc-1], &pp);
+                        if (!errno && *pp == '\0')
+                                break;
                 default:
                         bb_show_usage();
         }
-        if (opt & OPT_w) /* Pad to length of start or last */
-                width = MAX(strlen(*argv), strlen(argv[argc-1]));
 
-        /* You should note that this is pos-5.0.91 semantics, -- FK. */
+        /* Last checked to be compatible with: coreutils-6.10 */
+        width = 0;
+        frac_part = 0;
+        while (1) {
+                char *dot = strchrnul(*argv, '.');
+                int w = (dot - *argv);
+                int f = strlen(dot);
+                if (width < w)
+                        width = w;
+                argv++;
+                if (!*argv)
+                        break;
+                /* Why do the above _before_ frac check below?
+                 * Try "seq 1 2.0" and "seq 1.0 2.0":
+                 * coreutils never pay attention to the number
+                 * of fractional digits in last arg. */
+                if (frac_part < f)
+                        frac_part = f;
+        }
+        if (frac_part) {
+                frac_part--;
+                if (frac_part)
+                        width += frac_part + 1;
+        }
+        if (!(opt & OPT_w))
+                width = 0;
+
         sep = "";
-        while ((increment > 0 && i <= last) || (increment < 0 && i >= last)) {
-                printf("%s%0*g", sep, width, i);
+        v = first;
+        n = 0;
+        while (increment >= 0 ? v <= last : v >= last) {
+                printf("%s%0*.*f", sep, width, frac_part, v);
                 sep = opt_s;
-                i += increment;
+                /* v += increment; - would accumulate floating point errors */
+                n++;
+                v = first + n * increment;
         }
-        bb_putchar('\n');
+        if (n) /* if while loop executed at least once */
+                bb_putchar('\n');
+
         return fflush(stdout);
 }
diff --git a/docs/posix_conformance.txt b/docs/posix_conformance.txt
index a9176f503..5451a322d 100644
--- a/docs/posix_conformance.txt
+++ b/docs/posix_conformance.txt
@@ -189,7 +189,7 @@ df POSIX options
 df Busybox specific options: 
   -a, -m, -B SIZE, -i, -h
 Remark:
-- It seems that GNU df doesnt rount percents up in its output (thus its results are a bit different)
+- It seems that GNU df does not round percents up in its output (thus its results are a bit different)
 
 diff POSIX options
  option           | exists | compliant | remarks
diff --git a/testsuite/runtest b/testsuite/runtest
index cade871a2..2d60591fb 100755
--- a/testsuite/runtest
+++ b/testsuite/runtest
@@ -120,11 +120,13 @@ fi
 
 # Populate a directory with links to all busybox applets
 
+# Note: if $LINKSDIR/applet exists, we do not overwrite it.
+# Useful if one wants to run tests against a standard utility, not an applet.
 LINKSDIR="$bindir/runtest-tempdir-links"
-rm -rf "$LINKSDIR" 2>/dev/null
-mkdir "$LINKSDIR"
+#rm -rf "$LINKSDIR" 2>/dev/null
+mkdir "$LINKSDIR" 2>/dev/null
 for i in $implemented; do
-        ln -s "$bindir/busybox" "$LINKSDIR/$i"
+        ln -s "$bindir/busybox" "$LINKSDIR/$i" 2>/dev/null
 done
 
 # Set up option flags so tests can be selective.
@@ -142,7 +144,7 @@ for applet in $applets; do
 
         # Is this a new-style test?
         if [ -f "$applet.tests" ]; then
-                if [ ! -h "$LINKSDIR/$applet" ]; then
+                if [ ! -e "$LINKSDIR/$applet" ]; then
                         # (avoiding bash'ism "${applet:0:4}")
                         if ! echo "$applet" | grep "^all_" >/dev/null; then
                                 echo "SKIPPED: $applet (not built)"
diff --git a/testsuite/seq.tests b/testsuite/seq.tests
index 4e43d0ee1..817e1a724 100755
--- a/testsuite/seq.tests
+++ b/testsuite/seq.tests
@@ -29,16 +29,18 @@ testing "seq count up by 2" "seq 4 2 8" "4\n6\n8\n" "" ""
 testing "seq count down by 2" "seq 8 -2 4" "8\n6\n4\n" "" ""
 testing "seq count wrong way #1" "seq 4 -2 8" "" "" ""
 testing "seq count wrong way #2" "seq 8 2 4" "" "" ""
-# Fails: first item is printed as 3, not 3.0
-# note: makes sense to fix "seq 3 .30 4" case as well
 testing "seq count by .3" "seq 3 .3 4" "3.0\n3.3\n3.6\n3.9\n" "" ""
-testing "seq count by -.9" "seq .7 -.9 -2.2" "0.7\n-0.2\n-1.1\n-2\n" "" ""
-testing "seq count by zero" "seq 4 0 8 | head -n 10" "" "" ""
+testing "seq count by .30" "seq 3 .30 4" "3.00\n3.30\n3.60\n3.90\n" "" ""
+testing "seq count by .30 to 4.000" "seq 3 .30 4.000" "3.00\n3.30\n3.60\n3.90\n" "" ""
+testing "seq count by -.9" "seq .7 -.9 -2.2" "0.7\n-0.2\n-1.1\n-2.0\n" "" ""
+testing "seq count by zero" "seq 4 0 8 | head -n 10" "4\n4\n4\n4\n4\n4\n4\n4\n4\n4\n" "" ""
 
 testing "seq one argument with padding" "seq -w 003" "001\n002\n003\n" "" ""
 testing "seq two arguments with padding" "seq -w 005 7" "005\n006\n007\n" "" ""
 testing "seq count down by 3 with padding" "seq -w 8 -3 04" "08\n05\n" "" ""
-# Known to fail
-testing "seq count by .3 with padding" "seq -w 03 .3 0004" "003.0\n003.3\n003.6\n003.9\n" "" ""
+# Looks like a bug in coreutils 6.10: it uses width one less than needed
+# These tests contain the expected "fixed" output
+testing "seq count by .3 with padding 1" "seq -w 09 .3 11" "09.0\n09.3\n09.6\n09.9\n10.2\n10.5\n10.8\n" "" ""
+testing "seq count by .3 with padding 2" "seq -w 03 .3 0004" "0003.0\n0003.3\n0003.6\n0003.9\n" "" ""
 
 exit $FAILCOUNT