Add seq, and tests for it.

2 files changed, 72 insertions, 0 deletions

diff --git a/scripts/test/seq.test b/scripts/test/seq.test
new file mode 100755
index 0000000..d255f82
--- /dev/null
+++ b/scripts/test/seq.test
@@ -0,0 +1,25 @@
+#!/bin/bash
+
+[ -f testing.sh ] && . testing.sh
+
+#testing "name" "command" "result" "infile" "stdin"
+
+testing "seq (exit with error)" "seq 2> /dev/null || echo yes" "yes\n" "" ""
+testing "seq (exit with error)" "seq 1 2 3 4 2> /dev/null || echo yes" \
+        "yes\n" "" ""
+testing "seq one argument" "seq 3" "1\n2\n3\n" "" ""
+testing "seq two arguments" "seq 5 7" "5\n6\n7\n" "" ""
+testing "seq two arguments reversed" "seq 7 5" "" "" ""
+testing "seq two arguments equal" "seq 3 3" "3\n" "" ""
+testing "seq two arguments equal, arbitrary negative step" "seq 1 -15 1" \
+        "1\n" "" ""
+testing "seq two arguments equal, arbitrary positive step" "seq 1 +15 1" \
+        "1\n" "" ""
+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" "" "" ""
+testing "seq count by .3" "seq 3 .3 4" "3\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" "" "" ""
+
diff --git a/toys/seq.c b/toys/seq.c
new file mode 100644
index 0000000..8eb8fb8
--- /dev/null
+++ b/toys/seq.c
@@ -0,0 +1,47 @@
+/* vi: set sw=4 ts=4:
+ *
+ * seq.c - Count from first to last, by increment.
+ *
+ * Copyright 2006 Rob Landley <rob@landley.net>
+ *
+ * Not in SUSv3.  (Don't ask me why not.)
+
+USE_SEQ(NEWTOY(seq, "<1>3?+", TOYFLAG_USR|TOYFLAG_BIN))
+
+config SEQ
+	bool "seq"
+	default y
+	help
+	  usage: seq [first] [increment] last
+
+	  Count from first to last, by increment.  Omitted arguments default
+	  to 1.  Two arguments are used as first and last.  Arguments can be
+	  negative or floating point.
+*/
+
+#include "toys.h"
+
+void seq_main(void)
+{
+	double first, increment, last, dd;
+
+	// Parse command line arguments, with appropriate defaults.
+	// Note that any non-numeric arguments are treated as zero.
+	first = increment = 1;
+	switch (toys.optc) {
+		case 3:
+			increment = atof(toys.optargs[1]);
+		case 2:
+			first = atof(*toys.optargs);
+		default:
+			last = atof(toys.optargs[toys.optc-1]);
+	}
+
+	// Yes, we're looping on a double.  Yes rounding errors can accumulate if
+	// you use a non-integer increment.  Deal with it.
+	for (dd=first; (increment>0 && dd<=last) || (increment <0 && dd>=last);
+		dd+=increment)
+	{
+		printf("%g\n", dd);
+	}
+}