feat(build): validate SDK specs before generation

cmd/build/cmd_sdk.go

@@ -23,6 +23,10 @@ func runBuildSDK(ctx context.Context, specPath, lang, version string, dryRun boo
 		return coreerr.E("build.SDK", "failed to get working directory", err)
 	}
 
+	return runBuildSDKInDir(ctx, projectDir, specPath, lang, version, dryRun)
+}
+
+func runBuildSDKInDir(ctx context.Context, projectDir, specPath, lang, version string, dryRun bool) error {
 	// Load config
 	config := sdk.DefaultConfig()
 	if specPath != "" {
@@ -40,8 +44,8 @@ func runBuildSDK(ctx context.Context, specPath, lang, version string, dryRun boo
 	}
 	cli.Blank()
 
-	// Detect spec
-	detectedSpec, err := s.DetectSpec()
+	// Validate the spec before generating anything.
+	detectedSpec, err := s.ValidateSpec(ctx)
 	if err != nil {
 		cli.Print("%s %v\n", buildErrorStyle.Render(i18n.T("common.label.error")), err)
 		return err

cmd/build/cmd_sdk_test.go

@@ -0,0 +1,44 @@
+package buildcmd
+
+import (
+	"context"
+	"testing"
+
+	"dappco.re/go/core/build/internal/ax"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+const validBuildOpenAPISpec = `openapi: "3.0.0"
+info:
+  title: Test API
+  version: "1.0.0"
+paths:
+  /health:
+    get:
+      operationId: getHealth
+      responses:
+        "200":
+          description: OK
+`
+
+func TestRunBuildSDKInDir_ValidSpecDryRun_Good(t *testing.T) {
+	tmpDir := t.TempDir()
+	require.NoError(t, ax.WriteFile(ax.Join(tmpDir, "openapi.yaml"), []byte(validBuildOpenAPISpec), 0o644))
+
+	err := runBuildSDKInDir(context.Background(), tmpDir, "", "go", "", true)
+	require.NoError(t, err)
+}
+
+func TestRunBuildSDKInDir_InvalidDocument_Bad(t *testing.T) {
+	tmpDir := t.TempDir()
+	require.NoError(t, ax.WriteFile(ax.Join(tmpDir, "openapi.yaml"), []byte(`openapi: "3.0.0"
+info:
+  title: Test API
+paths: {}
+`), 0o644))
+
+	err := runBuildSDKInDir(context.Background(), tmpDir, "", "", "", true)
+	require.Error(t, err)
+	assert.Contains(t, err.Error(), "invalid OpenAPI spec")
+}