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authorDimitri Sokolyuk <demon@dim13.org>2019-07-06 17:17:46 +0200
committerDimitri Sokolyuk <demon@dim13.org>2019-07-06 17:17:46 +0200
commit1d2ca509c77cbb2af0475b1319cd840f8ce9a1d0 (patch)
tree05a838baaf4f96fbcce03d06090a2403ee56c878 /internal/flood
parent87e820722cf02054225b47a58f97d0824118292f (diff)
Split in packages
Diffstat (limited to 'internal/flood')
-rw-r--r--internal/flood/flood.go62
-rw-r--r--internal/flood/flood_test.go51
2 files changed, 113 insertions, 0 deletions
diff --git a/internal/flood/flood.go b/internal/flood/flood.go
new file mode 100644
index 0000000..b8a71d1
--- /dev/null
+++ b/internal/flood/flood.go
@@ -0,0 +1,62 @@
+package flood
+
+import (
+ "math"
+ "sort"
+ "strings"
+ "unicode"
+ "unicode/utf8"
+)
+
+const (
+ runes = 6
+ words = 6
+ black = "\u24B6\u262D\u272F\u262E\u2721\u5350\u534D\u2719\u0FD5\u0FD6\u16CB\uA5A6\u0FD7\u0FD8"
+)
+
+func entropy(s string) (e float64) {
+ n := make(map[rune]float64)
+ for _, r := range s {
+ n[r] += 1 / float64(len(s))
+ }
+ for _, v := range n {
+ e -= v * math.Log2(v)
+ }
+ return e
+}
+
+func Is(s string) bool {
+ if strings.ContainsAny(s, black) {
+ return true
+ }
+ if utf8.RuneCountInString(s) <= runes {
+ return false
+ }
+ if v := strings.Fields(s); len(v) >= words {
+ return commonWord(v) >= len(v)/2
+ }
+ return entropy(s) <= 1
+}
+
+func commonWord(v []string) int {
+ m := make(map[string]int)
+ for _, w := range v {
+ m[w]++
+ }
+ l := make([]int, len(m))
+ for _, n := range m {
+ l = append(l, n)
+ }
+ sort.Sort(sort.Reverse(sort.IntSlice(l)))
+ return l[0]
+}
+
+func noSpaceCompare(a, b string) bool {
+ dropSpaces := func(r rune) rune {
+ if unicode.IsSpace(r) {
+ return -1
+ }
+ return r
+ }
+ return strings.Map(dropSpaces, a) == strings.Map(dropSpaces, b)
+}
diff --git a/internal/flood/flood_test.go b/internal/flood/flood_test.go
new file mode 100644
index 0000000..c16da7c
--- /dev/null
+++ b/internal/flood/flood_test.go
@@ -0,0 +1,51 @@
+package flood
+
+import "testing"
+
+func TestFlood(t *testing.T) {
+ testCases := []struct {
+ line string
+ ok bool
+ }{
+ {`! ! ! ! ! ! ! !`, true},
+ {`test test test test abc abc`, true},
+ {`! test ! test ! test ! test !`, true},
+ {`a b c d e f g h i j`, false},
+ {`const union __infinity_un __infinity = { { 0, 0, 0, 0, 0, 0, 0xf0, 0x7f } };`, false},
+ {`a = b > 3 ? 2 : 4`, false},
+ {`AAAAAAAAAAAAAAAAAAAA`, true},
+ {`AAAAAAAAAABBBBBBBBBB`, true},
+ {`ivy 3 3 rho (iota 9) in 2 6 7 8 9`, false},
+ {"\u262etest", true},
+ }
+ for _, tc := range testCases {
+ t.Run(tc.line, func(t *testing.T) {
+ if Is(tc.line) != tc.ok {
+ t.Errorf("want %v", tc.ok)
+ }
+ })
+ }
+}
+
+func TestNoSpaceCompare(t *testing.T) {
+ testCases := []struct {
+ a, b string
+ ok bool
+ }{
+ {"", "", true},
+ {"x", "", false},
+ {"", "x", false},
+ {"x ", "x", true},
+ {" x", "x", true},
+ {"x x", "xx", true},
+ {"x x x", "x", false},
+ }
+ for _, tc := range testCases {
+ t.Run(tc.a+"?"+tc.b, func(t *testing.T) {
+ ok := noSpaceCompare(tc.a, tc.b)
+ if ok != tc.ok {
+ t.Errorf("got %v; want %v", ok, tc.ok)
+ }
+ })
+ }
+}