test: enhance assertions in OCIInstaller and list tests using testify

Signed-off-by: Matthieu MOREL <matthieu.morel35@gmail.com>

internal/plugin/installer/oci_installer_test.go

@@ -33,6 +33,8 @@ import (
 
 	"github.com/opencontainers/go-digest"
 	ocispec "github.com/opencontainers/image-spec/specs-go/v1"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 
 	"helm.sh/helm/v4/internal/test/ensure"
 	"helm.sh/helm/v4/pkg/cli"
@@ -415,16 +417,11 @@ func TestOCIInstaller_Install_WithGetterOptions(t *testing.T) {
 			// Install the plugin
 			err = Install(installer)
 			if tc.wantErr {
-				if err == nil {
+				require.Error(t, err, "Expected installation to fail, but it succeeded")
-					t.Error("Expected installation to fail, but it succeeded")
-				}
 			} else {
-				if err != nil {
+				require.NoError(t, err, "Expected installation to succeed, got error: %v", err)
-					t.Errorf("Expected installation to succeed, got error: %v", err)
 				// Verify plugin was installed to the actual path
-				} else if !isPlugin(actualPath) {
+				assert.True(t, isPlugin(actualPath), "Expected plugin directory %s to contain plugin.yaml", actualPath)
-					t.Errorf("Expected plugin directory %s to contain plugin.yaml", actualPath)
-				}
 			}
 		})
 	}

pkg/cmd/list_test.go

@@ -20,6 +20,9 @@ import (
 	"testing"
 	"time"
 
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
 	chart "helm.sh/helm/v4/pkg/chart/v2"
 	"helm.sh/helm/v4/pkg/release/common"
 	release "helm.sh/helm/v4/pkg/release/v1"
@@ -348,11 +351,8 @@ func TestReleaseListWriter(t *testing.T) {
 		t.Run(tt.name, func(t *testing.T) {
 			writer := newReleaseListWriter(tt.releases, tt.timeFormat, tt.noHeaders, tt.noColor)
 
-			if writer == nil {
+			require.NotNil(t, writer, "Expected writer to be non-nil")
-				t.Error("Expected writer to be non-nil")
+			assert.Len(t, writer.releases, len(tt.releases), "Expected %d releases, got %d", len(tt.releases), len(writer.releases))
-			} else if len(writer.releases) != len(tt.releases) {
-				t.Errorf("Expected %d releases, got %d", len(tt.releases), len(writer.releases))
-			}
 		})
 	}
 }