Rediscover Go settings only when Go work needs them

internal/candidate/check.go

@@ -53,13 +53,9 @@ func Check(ctx context.Context, request Request) (Candidate, error) {
 	}
 	if request.AfterValidate != nil {
 		callbackErr := request.AfterValidate(ctx, captured, request.ToolOwner)
-		refreshErr := request.ToolOwner.Refresh(ctx)
 		if callbackErr != nil {
 			return captured, fmt.Errorf("after candidate validation: %w", callbackErr)
 		}
-		if refreshErr != nil {
-			return captured, fmt.Errorf("refresh Go settings after candidate callback: %w", refreshErr)
-		}
 	}
 	if err := Recheck(ctx, captured, ""); err != nil {
 		return captured, err
@@ -143,13 +139,9 @@ func Validate(ctx context.Context, request Request, captured Candidate) error {
 	}
 	if request.AdditionalChecks != nil {
 		callbackErr := request.AdditionalChecks(ctx, captured)
-		refreshErr := owner.Refresh(ctx)
 		if callbackErr != nil {
 			return fmt.Errorf("validate candidate %s: %w", captured.Commit, callbackErr)
 		}
-		if refreshErr != nil {
-			return fmt.Errorf("refresh Go settings after additional checks: %w", refreshErr)
-		}
 	}
 	return nil
 }

internal/candidate/check_test.go

@@ -304,6 +304,28 @@ func TestCheckRefreshesGoSettingsAfterAdditionalChecks(t *testing.T) {
 	}
 }
 
+func TestCheckNeedsNoGoDiscoveryAfterFinalCallback(t *testing.T) {
+	repository := newRepository(t, "# Example Product v1.2.3\n\nRelease note.\n")
+	gitPath, err := exec.LookPath("git")
+	if err != nil {
+		t.Fatal(err)
+	}
+	gitOnly := t.TempDir()
+	if err := os.Symlink(gitPath, filepath.Join(gitOnly, "git")); err != nil {
+		t.Fatal(err)
+	}
+	_, err = Check(context.Background(), Request{
+		RepositoryDir: repository, Product: "Example Product", Version: testVersion,
+		AfterValidate: func(context.Context, Candidate, *gotool.Owner) error {
+			t.Setenv("PATH", gitOnly)
+			return nil
+		},
+	})
+	if err != nil {
+		t.Fatalf("completed Go work was rediscovered after final callback: %v", err)
+	}
+}
+
 func TestCheckSharesGoDiscoveryWithAfterValidateCallback(t *testing.T) {
 	if runtime.GOOS == "windows" {
 		t.Skip("the controlled Go command fixture uses a POSIX shell")