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-rw-r--r--src/pkg/strconv/fp_test.go149
1 files changed, 149 insertions, 0 deletions
diff --git a/src/pkg/strconv/fp_test.go b/src/pkg/strconv/fp_test.go
new file mode 100644
index 000000000..60d7ce6cf
--- /dev/null
+++ b/src/pkg/strconv/fp_test.go
@@ -0,0 +1,149 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package strconv
+import (
+ "bufio";
+ "fmt";
+ "io";
+ "os";
+ "strconv";
+ "strings";
+ "testing";
+)
+
+func pow2(i int) float64 {
+ switch {
+ case i < 0:
+ return 1 / pow2(-i);
+ case i == 0:
+ return 1;
+ case i == 1:
+ return 2;
+ }
+ return pow2(i/2) * pow2(i-i/2);
+}
+
+// Wrapper around strconv.Atof64. Handles dddddp+ddd (binary exponent)
+// itself, passes the rest on to strconv.Atof64.
+func myatof64(s string) (f float64, ok bool) {
+ a := strings.Split(s, "p");
+ if len(a) == 2 {
+ n, err := strconv.Atoi64(a[0]);
+ if err != nil {
+ return 0, false;
+ }
+ e, err1 := strconv.Atoi(a[1]);
+ if err1 != nil {
+ println("bad e", a[1]);
+ return 0, false;
+ }
+ v := float64(n);
+ // We expect that v*pow2(e) fits in a float64,
+ // but pow2(e) by itself may not. Be careful.
+ if e <= -1000 {
+ v *= pow2(-1000);
+ e += 1000;
+ for e < 0 {
+ v /= 2;
+ e++;
+ }
+ return v, true;
+ }
+ if e >= 1000 {
+ v *= pow2(1000);
+ e -= 1000;
+ for e > 0 {
+ v *= 2;
+ e--;
+ }
+ return v, true;
+ }
+ return v*pow2(e), true;
+ }
+ f1, err := strconv.Atof64(s);
+ if err != nil {
+ return 0, false;
+ }
+ return f1, true;
+}
+
+// Wrapper around strconv.Atof32. Handles dddddp+ddd (binary exponent)
+// itself, passes the rest on to strconv.Atof32.
+func myatof32(s string) (f float32, ok bool) {
+ a := strings.Split(s, "p");
+ if len(a) == 2 {
+ n, err := strconv.Atoi(a[0]);
+ if err != nil {
+ println("bad n", a[0]);
+ return 0, false;
+ }
+ e, err1 := strconv.Atoi(a[1]);
+ if err1 != nil {
+ println("bad p", a[1]);
+ return 0, false;
+ }
+ return float32(float64(n)*pow2(e)), true;
+ }
+ f1, err1 := strconv.Atof32(s);
+ if err1 != nil {
+ return 0, false;
+ }
+ return f1, true;
+}
+
+func TestFp(t *testing.T) {
+ f, err := os.Open("testfp.txt", os.O_RDONLY, 0);
+ if err != nil {
+ panicln("testfp: open testfp.txt:", err.String());
+ }
+ defer f.Close();
+
+ b := bufio.NewReader(f);
+
+ lineno := 0;
+ for {
+ line, err2 := b.ReadLineString('\n', false);
+ if err2 == io.ErrEOF {
+ break;
+ }
+ if err2 != nil {
+ panicln("testfp: read testfp.txt:", err2.String());
+ }
+ lineno++;
+ if len(line) == 0 || line[0] == '#' {
+ continue
+ }
+ a := strings.Split(line, " ");
+ if len(a) != 4 {
+ t.Error("testfp.txt:", lineno, ": wrong field count\n");
+ continue;
+ }
+ var s string;
+ var v float64;
+ switch a[0] {
+ case "float64":
+ var ok bool;
+ v, ok = myatof64(a[2]);
+ if !ok {
+ t.Error("testfp.txt:", lineno, ": cannot atof64 ", a[2]);
+ continue;
+ }
+ s = fmt.Sprintf(a[1], v);
+ case "float32":
+ v1, ok := myatof32(a[2]);
+ if !ok {
+ t.Error("testfp.txt:", lineno, ": cannot atof32 ", a[2]);
+ continue;
+ }
+ s = fmt.Sprintf(a[1], v1);
+ v = float64(v1);
+ }
+ if s != a[3] {
+ t.Error("testfp.txt:", lineno, ": ", a[0], " ", a[1], " ", a[2], " (", v, ") ",
+ "want ", a[3], " got ", s);
+ }
+//else print("testfp.txt:", lineno, ": worked! ", s, "\n");
+ }
+}