Shell: Use ps command which works for linux and mac

As part of 74d1f1b ps command
has `--sort=-pid` which doesn't work with macOS by default so in this
PR `--sort=-pid` option is removed and reverse sorting against pid is
implemented in `inspectProcessOutputForRecentlyUsedShell`. This way
this code works on mac/linux same way.

fixes: #4537

pkg/os/shell/shell.go

@@ -3,9 +3,11 @@ package shell
 import (
 	"fmt"
 	"os"
+	"sort"
 	"strconv"
 	"strings"
 
+	"github.com/crc-org/crc/v2/pkg/crc/logging"
 	crcos "github.com/crc-org/crc/v2/pkg/os"
 )
 
@@ -174,13 +176,13 @@ func detectShellByInvokingCommand(defaultShell string, command string, args []st
 	if detectedShell == "" {
 		return defaultShell
 	}
+	logging.Debugf("Detected shell: %s", detectedShell)
 	return detectedShell
 }
 
 // inspectProcessOutputForRecentlyUsedShell inspects output of ps command to detect currently active shell session.
 //
-// Note : This method assumes that ps command has already sorted the processes by `pid` in reverse order.
-// It parses the output into a struct, filters process types by name and returns the first element.
+// It parses the output into a struct, filters process types by name then reverse sort it with pid and returns the first element.
 //
 // It takes one argument:
 //
@@ -222,6 +224,11 @@ func inspectProcessOutputForRecentlyUsedShell(psCommandOutput string) string {
 			}
 		}
 	}
+	// Reverse sort the processes by PID (higher to lower)
+	sort.Slice(processOutputs, func(i, j int) bool {
+		return processOutputs[i].processID > processOutputs[j].processID
+	})
+
 	if len(processOutputs) > 0 {
 		return processOutputs[0].output
 	}

pkg/os/shell/shell_unix.go

@@ -15,7 +15,7 @@ var (
 
 // detect detects user's current shell.
 func detect() (string, error) {
-	detectedShell := detectShellByInvokingCommand("", "ps", []string{"-o", "pid=,comm=", "--sort=-pid"})
+	detectedShell := detectShellByInvokingCommand("", "ps", []string{"-o", "pid=,comm="})
 	if detectedShell == "" {
 		fmt.Printf("The default lines below are for a sh/bash shell, you can specify the shell you're using, with the --shell flag.\n\n")
 		return "", ErrUnknownShell

pkg/os/shell/shell_unix_test.go

@@ -33,7 +33,7 @@ func TestUnknownShell(t *testing.T) {
 	assert.Greater(t, nBytesRead, int64(0))
 	assert.Equal(t, "The default lines below are for a sh/bash shell, you can specify the shell you're using, with the --shell flag.\n\n", buf.String())
 	assert.Equal(t, "ps", mockCommandExecutor.commandName)
-	assert.Equal(t, []string{"-o", "pid=,comm=", "--sort=-pid"}, mockCommandExecutor.commandArgs)
+	assert.Equal(t, []string{"-o", "pid=,comm="}, mockCommandExecutor.commandArgs)
 	assert.Empty(t, shell)
 }
 
@@ -78,7 +78,7 @@ func TestDetect_GivenPsOutputContainsShell_ThenReturnShellProcessWithMostRecentP
 
 			// Then
 			assert.Equal(t, "ps", mockCommandExecutor.commandName)
-			assert.Equal(t, []string{"-o", "pid=,comm=", "--sort=-pid"}, mockCommandExecutor.commandArgs)
+			assert.Equal(t, []string{"-o", "pid=,comm="}, mockCommandExecutor.commandArgs)
 			assert.Equal(t, tt.expectedShellType, shell)
 			assert.NoError(t, err)
 		})

pkg/os/shell/shell_windows.go

@@ -64,7 +64,7 @@ func shellType(shell string, defaultShell string) string {
 	case strings.Contains(strings.ToLower(shell), "cmd"):
 		return "cmd"
 	case strings.Contains(strings.ToLower(shell), "wsl"):
-		return detectShellByInvokingCommand("bash", "wsl", []string{"-e", "bash", "-c", "ps -ao pid=,comm= --sort=-pid"})
+		return detectShellByInvokingCommand("bash", "wsl", []string{"-e", "bash", "-c", "ps -ao pid=,comm="})
 	case filepath.IsAbs(shell) && strings.Contains(strings.ToLower(shell), "bash"):
 		return "bash"
 	default:

pkg/os/shell/shell_windows_test.go

@@ -85,5 +85,5 @@ func TestDetectShellInWindowsSubsystemLinux(t *testing.T) {
 
 	// Then
 	assert.Equal(t, "wsl", mockCommandExecutor.commandName)
-	assert.Equal(t, []string{"-e", "bash", "-c", "ps -ao pid=,comm= --sort=-pid"}, mockCommandExecutor.commandArgs)
+	assert.Equal(t, []string{"-e", "bash", "-c", "ps -ao pid=,comm="}, mockCommandExecutor.commandArgs)
 }