chore: Standardise Error Codes (#286)

* fix: Misc error handling fixes

* fix: Sandbox error translation

internal/runner/execute.go

@@ -10,12 +10,13 @@ import (
 	"sync"
 
 	"github.com/safedep/dry/log"
+	"github.com/safedep/dry/usefulerror"
+	"github.com/safedep/pmg/errcodes"
 	"github.com/safedep/pmg/internal/pty"
 	"github.com/safedep/pmg/internal/shim"
 	"github.com/safedep/pmg/packagemanager"
 	"github.com/safedep/pmg/sandbox"
 	"github.com/safedep/pmg/sandbox/executor"
-	"github.com/safedep/dry/usefulerror"
 )
 
 type ExecutionMode int
@@ -141,6 +142,7 @@ func runPTY(
 	if !result.ShouldRun() {
 		return usefulerror.NewUsefulError().
 			Wrap(fmt.Errorf("sandbox not supported for PTY sessions")).
+			WithCode(errcodes.InvalidArgument).
 			WithHumanError("Sandbox executed command cannot be used with PTY session. Please use non-interactive TTY mode instead.")
 	}
 

internal/ui/error_convert_test.go

@@ -76,7 +76,7 @@ func Test_ErrorConverters(t *testing.T) {
 			inputError: fmt.Errorf("more context: %w",
 				fmt.Errorf("outer context: %w",
 					errors.New("root cause error"))),
-			wantNil:    true,
+			wantNil: true,
 		},
 		{
 			name:       "Nil",
@@ -114,6 +114,65 @@ func Test_ErrorConverters(t *testing.T) {
 	}
 }
 
+func Test_convertToUsefulError(t *testing.T) {
+	tests := []struct {
+		name           string
+		inputError     error
+		wantCode       string
+		wantHumanError string
+		wantNil        bool
+	}{
+		{
+			name:       "Nil",
+			inputError: nil,
+			wantNil:    true,
+		},
+		{
+			name: "AlreadyUseful",
+			inputError: usefulerror.NewUsefulError().
+				WithCode("CUSTOM").
+				WithHumanError("Already useful"),
+			wantCode:       "CUSTOM",
+			wantHumanError: "Already useful",
+		},
+		{
+			name:           "Converted",
+			inputError:     &fs.PathError{Op: "open", Path: "/nonexistent/file.txt", Err: os.ErrNotExist},
+			wantCode:       errcodes.NotFound,
+			wantHumanError: "File or directory not found: /nonexistent/file.txt",
+		},
+		{
+			name:           "UnknownFallsBackToRootCause",
+			inputError:     errors.New("some unknown error"),
+			wantCode:       errcodes.Unknown,
+			wantHumanError: "some unknown error",
+		},
+		{
+			name: "UnknownWrappedExtractsRootCause",
+			inputError: fmt.Errorf("more context: %w",
+				fmt.Errorf("outer context: %w",
+					errors.New("root cause error"))),
+			wantCode:       errcodes.Unknown,
+			wantHumanError: "root cause error",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result := convertToUsefulError(tt.inputError)
+
+			if tt.wantNil {
+				assert.Nil(t, result)
+				return
+			}
+
+			assert.NotNil(t, result)
+			assert.Equal(t, tt.wantCode, result.Code())
+			assert.Equal(t, tt.wantHumanError, result.HumanError())
+		})
+	}
+}
+
 func TestExtractPathFromError(t *testing.T) {
 	tests := []struct {
 		name     string