fix(gen): source go-github version from go.mod

gen/generate.go

@@ -41,15 +41,19 @@ func main() {
 		return
 	}
 
-	out := filepath.Join(".", *outputDir)
-	err := os.MkdirAll(out, os.ModePerm)
+	imp, err := goGithubImportPath("go.mod")
 	if err != nil {
+		panic(err)
+	}
+	params.GoGithubImport = imp
+
+	out := filepath.Join(".", *outputDir)
+	if err := os.MkdirAll(out, os.ModePerm); err != nil {
 		panic("failed to create output directory")
 	}
 
 	// create events.go
-	err = ExecuteWebhookEventTemplate(filepath.Join(out, "events"), params)
-	if err != nil {
+	if err := ExecuteWebhookEventTemplate(filepath.Join(out, "events"), params); err != nil {
 		panic(err)
 	}
 
@@ -59,7 +63,8 @@ func main() {
 		fileName := "events_" + param.Name
 		outFile := filepath.Join(out, fileName)
 		err := ExecuteWebhookEventTypesTemplate(outFile, TemplateParameters{
-			Webhooks: []GithubWebhooks{param},
+			GoGithubImport: imp,
+			Webhooks:       []GithubWebhooks{param},
 		})
 		if err != nil {
 			panic(err)

gen/gomod.go

@@ -0,0 +1,38 @@
+package main
+
+import (
+	"fmt"
+	"os"
+	"regexp"
+	"sort"
+)
+
+var goGithubModuleRE = regexp.MustCompile(`github\.com/google/go-github/v\d+`)
+
+// goGithubImportPath reads gomodPath and returns the go-github package import
+// path (module path + "/github") derived from the module's require directive.
+// This keeps the go-github major version defined in exactly one place.
+func goGithubImportPath(gomodPath string) (string, error) {
+	data, err := os.ReadFile(gomodPath)
+	if err != nil {
+		return "", fmt.Errorf("read %s: %w", gomodPath, err)
+	}
+	matches := goGithubModuleRE.FindAllString(string(data), -1)
+	uniq := map[string]struct{}{}
+	for _, m := range matches {
+		uniq[m] = struct{}{}
+	}
+	switch len(uniq) {
+	case 0:
+		return "", fmt.Errorf("no github.com/google/go-github require found in %s", gomodPath)
+	case 1:
+		return matches[0] + "/github", nil
+	default:
+		uniqueVersions := make([]string, 0, len(uniq))
+		for v := range uniq {
+			uniqueVersions = append(uniqueVersions, v)
+		}
+		sort.Strings(uniqueVersions)
+		return "", fmt.Errorf("multiple go-github module versions found in %s: %v", gomodPath, uniqueVersions)
+	}
+}

gen/gomod_test.go

@@ -0,0 +1,58 @@
+package main
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+)
+
+func writeGoMod(t *testing.T, content string) string {
+	t.Helper()
+	dir := t.TempDir()
+	p := filepath.Join(dir, "go.mod")
+	if err := os.WriteFile(p, []byte(content), 0o644); err != nil {
+		t.Fatal(err)
+	}
+	return p
+}
+
+func TestGoGithubImportPath(t *testing.T) {
+	p := writeGoMod(t, `module github.com/cbrgm/githubevents/v2
+
+go 1.25.0
+
+require (
+	github.com/google/go-github/v89 v89.0.0
+	golang.org/x/sync v0.22.0
+)
+`)
+	got, err := goGithubImportPath(p)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if want := "github.com/google/go-github/v89/github"; got != want {
+		t.Fatalf("got %q, want %q", got, want)
+	}
+}
+
+func TestGoGithubImportPathMissing(t *testing.T) {
+	p := writeGoMod(t, "module x\n\ngo 1.25.0\n")
+	if _, err := goGithubImportPath(p); err == nil {
+		t.Fatal("expected error when no go-github require present")
+	}
+}
+
+func TestGoGithubImportPathMultiple(t *testing.T) {
+	p := writeGoMod(t, `module github.com/cbrgm/githubevents/v2
+
+go 1.25.0
+
+require (
+	github.com/google/go-github/v89 v89.0.0
+	github.com/google/go-github/v90 v90.0.0
+)
+`)
+	if _, err := goGithubImportPath(p); err == nil {
+		t.Fatal("expected error when multiple distinct go-github versions present")
+	}
+}

gen/template_params.go

@@ -2,7 +2,9 @@ package main
 
 // TemplateParameters represents template parameters.
 type TemplateParameters struct {
-	Webhooks []GithubWebhooks
+	// GoGithubImport is the go-github package import path, derived from go.mod.
+	GoGithubImport string
+	Webhooks       []GithubWebhooks
 }
 
 // GithubWebhooks represents a Github webhook event type parameters.

gen/template_webhook_event.go.tmpl

@@ -10,7 +10,7 @@ package githubevents
 import (
 	"context"
 	"fmt"
-	"github.com/google/go-github/v89/github"
+	"{{ .GoGithubImport }}"
 	"golang.org/x/sync/errgroup"
 	"net/http"
 	"sync"

gen/template_webhook_event_tests.go.tmpl

@@ -10,7 +10,7 @@ package githubevents
 import (
 	"context"
 	"errors"
-	"github.com/google/go-github/v89/github"
+	"{{ .GoGithubImport }}"
 	"testing"
 	"sync"
 )

gen/template_webhook_event_types.go.tmpl

@@ -10,7 +10,7 @@ package githubevents
 import (
 	"context"
 	"fmt"
-	"github.com/google/go-github/v89/github"
+	"{{ .GoGithubImport }}"
 	"golang.org/x/sync/errgroup"
 )