add cvss/v2score and tests

2 files changed, 124 insertions, 0 deletions

diff --git a/cvss/v2score.go b/cvss/v2score.go
new file mode 100644
index 0000000..5740c09
--- /dev/null
+++ b/cvss/v2score.go
@@ -0,0 +1,32 @@
+package cvss
+
+import (
+  "fmt"
+)
+
+// Individual CVSS v2 score.
+//
+// Note: since scores range from 0.0 to 10.0 with one decimal place of
+// precision, they can be safely represented as a uint8.
+type v2Score uint8
+
+// Return floating point representation of score.
+func newV2Score(val float64) (v2Score, error) {
+  // check score range
+  if val < 0.0 || val > 10.0 {
+    return v2Score(0), fmt.Errorf("score value out of range [0, 10]: %f", val)
+  }
+
+  // convert to score, return success
+  return v2Score(uint8(10.0 * val)), nil
+}
+
+// Return string representation of score.
+func (s v2Score) String() string {
+  return fmt.Sprintf("%d.%d", s / 10, s % 10)
+}
+
+// Return floating point representation of score.
+func (s v2Score) Float() float32 {
+  return float32(s) / 10.0
+}
diff --git a/cvss/v2score_test.go b/cvss/v2score_test.go
new file mode 100644
index 0000000..f83b76e
--- /dev/null
+++ b/cvss/v2score_test.go
@@ -0,0 +1,92 @@
+package cvss
+
+import (
+  "strconv"
+  "testing"
+)
+
+func TestNewV2Score(t *testing.T) {
+  // pass tests
+  for exp := 0; exp < 100; exp++ {
+    val := float64(exp) / 10.0
+
+    t.Run(strconv.FormatInt(int64(exp), 10), func(t *testing.T) {
+      got, err := newV2Score(val)
+      if err != nil {
+        t.Error(err)
+      } else if int(got) != exp {
+        t.Errorf("got %d, exp %d", int(got), exp)
+      }
+    })
+  }
+
+  // fail tests
+  failTests := []float64 { -10.0, -0.1, 10.1, 100.0 }
+  for _, val := range(failTests) {
+    t.Run(strconv.FormatFloat(val, 'f', 2, 64), func(t *testing.T) {
+      if got, err := newV2Score(val); err == nil {
+        t.Errorf("got %v, exp error", got)
+      }
+    })
+  }
+}
+
+func TestV2ScoreString(t *testing.T) {
+  tests := []struct {
+    val float64
+    exp string
+  } {
+    { 0.0, "0.0" },
+    { 1.0, "1.0" },
+    { 1.1, "1.1" },
+    { 1.2, "1.2" },
+    { 2.0, "2.0" },
+    { 7.5, "7.5" },
+    { 10.0, "10.0" },
+  }
+
+  for _, test := range(tests) {
+    t.Run(test.exp, func(t *testing.T) {
+      if val, err := newV2Score(test.val); err != nil {
+        t.Error(err)
+      } else if val.String() != test.exp {
+        t.Errorf("got \"%s\", exp \"%s\"", val.String(), test.exp)
+      }
+    })
+  }
+}
+
+func TestV2ScoreFloat(t *testing.T) {
+  tests := []struct {
+    val float64
+    exp float32
+  } {
+    { 0.0, float32(0.0) },
+    { 1.0, float32(1.0) },
+    { 1.1, float32(1.1) },
+    { 1.2, float32(1.2) },
+    { 2.0, float32(2.0) },
+    { 7.5, float32(7.5) },
+    { 7.5, float32(7.5) },
+    { 10.0, float32(10.0) },
+
+    // test weird cases
+    { 7.59, float32(7.5) },
+    { 8.11111111, float32(8.1) },
+  }
+
+  for _, test := range(tests) {
+    t.Run(strconv.FormatFloat(test.val, 'f', 2, 64), func(t *testing.T) {
+      s, err := newV2Score(test.val)
+      if err != nil {
+        t.Error(err)
+        return
+      }
+
+      got := s.Float()
+      if got != test.exp {
+        t.Errorf("got \"%f\", exp \"%f\"", got, test.exp)
+      }
+    })
+  }
+}