cuducos.me
🇧🇷 CNPJ validation in Go
1st commit
+207
+30
.github/workflows/tests.yml
+30
.github/workflows/tests.yml
···
1
+
name: Tests
2
+
3
+
on: [pull_request, push]
4
+
5
+
jobs:
6
+
7
+
build:
8
+
name: Build
9
+
runs-on: ubuntu-latest
10
+
steps:
11
+
12
+
- name: Set up Go 1.14
13
+
uses: actions/setup-go@v1
14
+
with:
15
+
go-version: 1.14
16
+
id: go
17
+
18
+
- name: Check out code into the Go module directory
19
+
uses: actions/checkout@v2
20
+
21
+
- name: Get dependencies
22
+
run: |
23
+
go get -v -t -d ./...
24
+
if [ -f Gopkg.toml ]; then
25
+
curl https://raw.githubusercontent.com/golang/dep/master/install.sh | sh
26
+
dep ensure
27
+
fi
28
+
29
+
- name: Build
30
+
run: go test
+12
LICENSE
+12
LICENSE
···
1
+
Copyright (c) 2020 Eduardo Cuducos
2
+
All rights reserved.
3
+
4
+
Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
5
+
6
+
1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
7
+
8
+
2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
9
+
10
+
3. Neither the name of the copyright holder nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.
11
+
12
+
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+30
README.md
+30
README.md
···
1
+
# Go CNPJ []()[](https://godoc.org/github.com/cuducos/go-cnpj)
2
+
3
+
A Go module to validate CNPJ numbers (Brazilian companies unique identifier for the Federal Revenue).
4
+
5
+
```go
6
+
package main
7
+
8
+
import "github.com/cuducos/go-cnpj"
9
+
10
+
11
+
func main() {
12
+
// these return true
13
+
cnpj.IsValid("11222333000181")
14
+
cnpj.IsValid("11.222.333/0001-81")
15
+
16
+
// these return false
17
+
cnpj.IsValid("11.111.111/1111-11")
18
+
cnpj.IsValid("12.345.678 9012-34")
19
+
cnpj.IsValid("AB.CDE.FGH/IJKL-MN")
20
+
cnpj.IsValid("123")
21
+
22
+
// this returns 11111111111111
23
+
cnpj.Unmask("11.111.111/1111-11")
24
+
25
+
// this returns 11.111.111/1111-11
26
+
cnpj.Mask("11111111111111")
27
+
}
28
+
```
29
+
30
+
Based on [Go CPF](https://github.com/cuducos/go-cpf) ❤️
+57
cnpj.go
+57
cnpj.go
···
1
+
package cnpj
2
+
3
+
import (
4
+
"fmt"
5
+
"regexp"
6
+
"strconv"
7
+
"strings"
8
+
)
9
+
10
+
11
+
12
+
func checksum(ds []int64, ref []int64) int64 {
13
+
var s int64
14
+
for i, n := range ref {
15
+
s += n * ds[i]
16
+
}
17
+
r := s % 11
18
+
if r < 2 {
19
+
return 0
20
+
}
21
+
return 11 - r
22
+
}
23
+
24
+
//IsValid checks whether CNPJ number is valid or not
25
+
func IsValid(n string) bool {
26
+
u := Unmask(n)
27
+
if len(u) != 14 {
28
+
return false
29
+
}
30
+
31
+
ds := make([]int64, 14)
32
+
for i, v := range strings.Split(u, "") {
33
+
c, err := strconv.ParseInt(v, 10, 32)
34
+
if err != nil {
35
+
return false
36
+
}
37
+
ds[i] = c
38
+
}
39
+
40
+
r1 := []int64{5,4,3,2,9,8,7,6,5,4,3,2}
41
+
r2 := []int64{6,5,4,3,2,9,8,7,6,5,4,3,2}
42
+
return checksum(ds, r1) == ds[12] && checksum(ds, r2) == ds[13]
43
+
}
44
+
45
+
//Mask returns the CNPJ number formatted
46
+
func Mask(n string) string {
47
+
u := Unmask(n)
48
+
if len(u) != 14 {
49
+
return n
50
+
}
51
+
return fmt.Sprintf("%s.%s.%s/%s-%s", u[:2], u[2:5], u[5:8], u[8:12], u[12:])
52
+
}
53
+
54
+
//Unmask removes any non-digit (numeric) from the CNPJ number
55
+
func Unmask(n string) string {
56
+
return regexp.MustCompile(`\D`).ReplaceAllString(n, "")
57
+
}
+75
cnpj_test.go
+75
cnpj_test.go
···
1
+
package cnpj
2
+
3
+
import (
4
+
"fmt"
5
+
"testing"
6
+
)
7
+
8
+
func TestMask(t *testing.T) {
9
+
for _, tc := range []struct {
10
+
cpf string
11
+
expected string
12
+
}{
13
+
{"11111111111111", "11.111.111/1111-11"},
14
+
{"123456", "123456"},
15
+
{"11223344556677889900", "11223344556677889900"},
16
+
} {
17
+
if got := Mask(tc.cpf); tc.expected != got {
18
+
t.Errorf("Mask(\"%s\") = %v; expected %s", tc.cpf, got, tc.expected)
19
+
}
20
+
}
21
+
}
22
+
23
+
func TestUnmask(t *testing.T) {
24
+
if got := Unmask("11.111.111/1111-11"); "11111111111111" != got {
25
+
t.Errorf("Unmask(\"11.111.111/1111-11\") = %v; want 11111111111111", got)
26
+
}
27
+
}
28
+
29
+
func TestIsValid(t *testing.T) {
30
+
for _, tc := range []struct {
31
+
cpf string
32
+
expected bool
33
+
}{
34
+
{"11222333000181", true},
35
+
{"11.222.333/0001-81", true},
36
+
{"123", false},
37
+
{"11.111.111/1111-11", false},
38
+
{"12.345.678 9012-34", false},
39
+
{"AB.CDE.FGH/IJKL-MN", false},
40
+
} {
41
+
if got := IsValid(tc.cpf); tc.expected != got {
42
+
t.Errorf("IsValid(%v) = %v; expected %v", tc.cpf, got, tc.expected)
43
+
}
44
+
}
45
+
}
46
+
47
+
func ExampleIsValid_validUnmasked() {
48
+
fmt.Println(IsValid("11222333000181"))
49
+
// Output: true
50
+
}
51
+
52
+
func ExampleIsValid_validMasked() {
53
+
fmt.Println(IsValid("11.222.333/0001-81"))
54
+
// Output: true
55
+
}
56
+
57
+
func ExampleIsValid_invalid() {
58
+
fmt.Println(IsValid("11.111.111/1111-11"))
59
+
// Output: false
60
+
}
61
+
62
+
func ExampleMask_valid() {
63
+
fmt.Println(Mask("11111111111111"))
64
+
// Output: 11.111.111/1111-11
65
+
}
66
+
67
+
func ExampleMask_invalid() {
68
+
fmt.Println(Mask("42"))
69
+
// Output: 42
70
+
}
71
+
72
+
func ExampleUnmask() {
73
+
fmt.Println(Unmask("11.111.111/1111-11"))
74
+
// Output: 11111111111111
75
+
}