feat: add magic string check for linked issues (#113)

internal/client.go

@@ -14,6 +14,7 @@ import (
 // Designed this way for easier testing
 type GithubClient interface {
 	GetPullRequest(context.Context, *entity.Meta, int) (*entity.PullRequest, error)
+	GetIssue(context.Context, *entity.Meta, int) (*entity.IssueReference, error)
 	GetIssueReferences(context.Context, *entity.Meta, int) ([]*entity.IssueReference, error)
 	GetCommits(context.Context, *entity.Meta, int) ([]*entity.Commit, error)
 	GetPermissions(context.Context, *entity.Meta, string) ([]string, error)
@@ -98,6 +99,38 @@ func (c *githubClient) GetPullRequest(
 	}, nil
 }
 
+func (c *githubClient) GetIssue(
+	ctx context.Context,
+	meta *entity.Meta,
+	issueNumber int,
+) (*entity.IssueReference, error) {
+	var query struct {
+		Repository struct {
+			Issue struct {
+				Number int
+			} `graphql:"issue(number: $number)"`
+		} `graphql:"repository(owner: $owner, name: $name)"`
+	}
+
+	variables := map[string]interface{}{
+		"owner":  githubv4.String(meta.Owner),
+		"name":   githubv4.String(meta.Name),
+		"number": githubv4.Int(issueNumber),
+	}
+
+	var issue *entity.IssueReference
+
+	err := c.gqlClient.Query(ctx, &query, variables)
+	if err != nil {
+		return issue, err
+	}
+
+	return &entity.IssueReference{
+		Number: issueNumber,
+		Meta:   *meta,
+	}, nil
+}
+
 func (c *githubClient) GetIssueReferences(
 	ctx context.Context,
 	meta *entity.Meta,

internal/mocks/client_mock.go

@@ -156,6 +156,27 @@ func (m *githubClientMock) Close(
 	return errors.New("error")
 }
 
+func (m *githubClientMock) GetIssue(
+	_ context.Context,
+	_ *entity.Meta,
+	issueNumber int,
+) (*entity.IssueReference, error) {
+	switch issueNumber {
+	case 2:
+		return &entity.IssueReference{
+			Number: 2,
+			Meta: entity.Meta{
+				Owner: "Namchee",
+				Name:  "conventional-pr",
+			},
+		}, nil
+	case 3:
+		return &entity.IssueReference{}, nil
+	default:
+		return nil, errors.New("mock error")
+	}
+}
+
 func (m *githubClientMock) GetIssueReferences(
 	_ context.Context,
 	_ *entity.Meta,

internal/validator/issue.go

@@ -2,12 +2,18 @@ package validator
 
 import (
 	"context"
+	"regexp"
+	"strconv"
 
 	"github.com/Namchee/conventional-pr/internal"
 	"github.com/Namchee/conventional-pr/internal/constants"
 	"github.com/Namchee/conventional-pr/internal/entity"
 )
 
+var (
+	keywordPattern = regexp.MustCompile(`(?mi)\b(close|closes|closed|fix|fixes|fixed|resolve|resolves|resolved) #(\d+)\b`)
+)
+
 type issueValidator struct {
 	Name string
 
@@ -65,9 +71,40 @@ func (v *issueValidator) IsValid(
 		}
 	}
 
+	if v.hasIssueMagicString(ctx, pullRequest) {
+		return &entity.ValidationResult{
+			Name:   constants.IssueValidatorName,
+			Active: true,
+			Result: nil,
+		}
+	}
+
 	return &entity.ValidationResult{
 		Name:   constants.IssueValidatorName,
 		Active: true,
 		Result: constants.ErrNoIssue,
 	}
 }
+
+func (v *issueValidator) hasIssueMagicString(
+	ctx context.Context,
+	pullRequest *entity.PullRequest,
+) bool {
+	keywords := keywordPattern.FindAllStringSubmatch(pullRequest.Body, -1)
+
+	for _, number := range keywords {
+		num, _ := strconv.Atoi(number[2])
+
+		issue, _ := v.client.GetIssue(
+			context.Background(),
+			&pullRequest.Repository,
+			num,
+		)
+
+		if issue != nil {
+			return true
+		}
+	}
+
+	return false
+}

internal/validator/issue_test.go

@@ -15,6 +15,7 @@ func TestIssueValidator_IsValid(t *testing.T) {
 		config   bool
 		meta     *entity.Meta
 		prNumber int
+		body     string
 	}
 	tests := []struct {
 		name string
@@ -85,10 +86,27 @@ func TestIssueValidator_IsValid(t *testing.T) {
 				Result: constants.ErrNoIssue,
 			},
 		},
+		{
+			name: "should pass if issue is referenced as magic string",
+			args: args{
+				prNumber: 2,
+				meta: &entity.Meta{
+					Name:  "conventional-pr",
+					Owner: "namcheee",
+				},
+				body:   "Closes #3",
+				config: true,
+			},
+			want: &entity.ValidationResult{
+				Name:   constants.IssueValidatorName,
+				Active: true,
+				Result: nil,
+			},
+		},
 		{
 			name: "should pass if data fetching failed",
 			args: args{
-				prNumber: 3,
+				prNumber: 99,
 				meta: &entity.Meta{
 					Name:  "conventional-pr",
 					Owner: "Namchee",
@@ -111,6 +129,7 @@ func TestIssueValidator_IsValid(t *testing.T) {
 			pullRequest := &entity.PullRequest{
 				Number:     tc.args.prNumber,
 				Repository: *tc.args.meta,
+				Body:       tc.args.body,
 			}
 
 			client := mocks.NewGithubClientMock()