refactor: rework plugin cmd (#82)

BREAKING CHANGE: `types.Cmd` was moved to `exec.Cmd` and the `Private` field from the struct was removed. The filed `Trace` is now a bool field instead of a bool pointer, and the helper method `SetTrace` was also removed.

BREAKING CHANGE: The method `trace.Cmd` was removed, please use the `Trace` field of `exec.Cmd`.

exec/command.go

@@ -0,0 +1,58 @@
+package exec
+
+import (
+	"fmt"
+	"io"
+	"os"
+	"os/exec"
+	"strings"
+
+	"golang.org/x/sys/execabs"
+)
+
+// Cmd represents a command to be executed, with options to control its behavior.
+// The Cmd struct embeds the standard library's exec.Cmd, adding additional fields
+// to control the command's output and tracing.
+type Cmd struct {
+	*exec.Cmd
+	Trace       bool      // Print composed command before execution.
+	TraceWriter io.Writer // Where to write the trace output.
+}
+
+// Run runs the command and waits for it to complete.
+// If there is an error starting the command, it is returned.
+// Otherwise, the command is waited for and its exit status is returned.
+func (c *Cmd) Run() error {
+	if c.Trace {
+		fmt.Fprintf(c.TraceWriter, "+ %s\n", strings.Join(c.Args, " "))
+	}
+
+	if err := c.Start(); err != nil {
+		return err
+	}
+
+	return c.Wait()
+}
+
+// Command creates a new Cmd struct with the given name and arguments. It looks up the
+// absolute path of the executable using execabs.LookPath, and sets up the Cmd with
+// the necessary environment and output streams. The Cmd is configured to trace
+// the command execution by setting Trace to true and TraceWriter to os.Stdout.
+func Command(name string, arg ...string) (*Cmd, error) {
+	abs, err := execabs.LookPath(name)
+	if err != nil {
+		return nil, fmt.Errorf("could not find executable %q: %w", name, err)
+	}
+
+	cmd := &Cmd{
+		Cmd:         execabs.Command(abs, arg...),
+		Trace:       true,
+		TraceWriter: os.Stdout,
+	}
+
+	cmd.Env = os.Environ()
+	cmd.Stdout = os.Stdout
+	cmd.Stderr = os.Stderr
+
+	return cmd, nil
+}

exec/command_test.go

@@ -1,4 +1,4 @@
-package types
+package exec
 
 import (
 	"bytes"
@@ -20,7 +20,7 @@ func TestCmdRun(t *testing.T) {
 		{
 			name: "trace enabled",
 			cmd: &Cmd{
-				Trace: boolPtr(true),
+				Trace: true,
 				Cmd: &exec.Cmd{
 					Path: "/usr/bin/echo",
 					Args: []string{"echo", "hello"},
@@ -30,19 +30,20 @@ func TestCmdRun(t *testing.T) {
 			wantStdout: "hello\n",
 		},
 		{
-			name: "private output",
+			name: "trace disabled",
 			cmd: &Cmd{
-				Private: true,
+				Trace: false,
 				Cmd: &exec.Cmd{
 					Path: "/usr/bin/echo",
 					Args: []string{"echo", "hello"},
 				},
 			},
-			wantTrace: "+ echo hello\n",
+			wantStdout: "hello\n",
 		},
 		{
 			name: "custom env",
 			cmd: &Cmd{
+				Trace: true,
 				Cmd: &exec.Cmd{
 					Path: "/bin/sh",
 					Args: []string{"sh", "-c", "echo $TEST"},
@@ -52,21 +53,10 @@ func TestCmdRun(t *testing.T) {
 			wantTrace:  "+ sh -c echo $TEST\n",
 			wantStdout: "1\n",
 		},
-		{
-			name: "custom stdout",
-			cmd: &Cmd{
-				Cmd: &exec.Cmd{
-					Path:   "/bin/sh",
-					Args:   []string{"sh", "-c", "echo hello"},
-					Stdout: new(bytes.Buffer),
-				},
-			},
-			wantTrace:  "+ sh -c echo hello\n",
-			wantStdout: "hello\n",
-		},
 		{
 			name: "custom stderr",
 			cmd: &Cmd{
+				Trace: true,
 				Cmd: &exec.Cmd{
 					Path:   "/bin/sh",
 					Args:   []string{"sh", "-c", "echo error >&2"},
@@ -76,6 +66,16 @@ func TestCmdRun(t *testing.T) {
 			wantTrace:  "+ sh -c echo error >&2\n",
 			wantStderr: "error\n",
 		},
+		{
+			name: "error",
+			cmd: &Cmd{
+				Trace: true,
+				Cmd: &exec.Cmd{
+					Path: "/invalid/path",
+				},
+			},
+			wantErr: true,
+		},
 	}
 
 	for _, tt := range tests {
@@ -101,42 +101,3 @@ func TestCmdRun(t *testing.T) {
 		})
 	}
 }
-
-func TestCmdSetTrace(t *testing.T) {
-	tests := []struct {
-		name     string
-		cmd      *Cmd
-		trace    bool
-		expected *bool
-	}{
-		{
-			name:     "set trace to true",
-			cmd:      &Cmd{},
-			trace:    true,
-			expected: boolPtr(true),
-		},
-		{
-			name:     "set trace to false",
-			cmd:      &Cmd{},
-			trace:    false,
-			expected: boolPtr(false),
-		},
-		{
-			name:     "overwrite existing trace value",
-			cmd:      &Cmd{Trace: boolPtr(true)},
-			trace:    false,
-			expected: boolPtr(false),
-		},
-	}
-
-	for _, tt := range tests {
-		t.Run(tt.name, func(t *testing.T) {
-			tt.cmd.SetTrace(tt.trace)
-			assert.Equal(t, tt.expected, tt.cmd.Trace)
-		})
-	}
-}
-
-func boolPtr(b bool) *bool {
-	return &b
-}

trace/http.go

@@ -12,9 +12,6 @@ import (
 	"fmt"
 	"net/http/httptrace"
 	"net/textproto"
-	"os"
-	"os/exec"
-	"strings"
 
 	"github.com/rs/zerolog/log"
 )
@@ -120,8 +117,3 @@ func HTTP(ctx context.Context) context.Context {
 		},
 	})
 }
-
-// Cmd prints the executed command to stdout.
-func Cmd(cmd *exec.Cmd) {
-	fmt.Fprintf(os.Stdout, "+ %s\n", strings.Join(cmd.Args, " "))
-}

types/command.go

@@ -1,67 +0,0 @@
-package types
-
-import (
-	"fmt"
-	"io"
-	"os"
-	"strings"
-
-	"golang.org/x/sys/execabs"
-)
-
-// Cmd represents a command to be executed. It extends the execabs.Cmd struct
-// and adds fields for controlling the command's execution, such as whether
-// it should be executed in private mode (with output discarded) and whether
-// its execution should be traced.
-type Cmd struct {
-	*execabs.Cmd
-	Private     bool
-	Trace       *bool
-	TraceWriter io.Writer
-}
-
-// Run executes the command and waits for it to complete.
-// If the Trace field is nil, it is set to true.
-// The Env, Stdout, and Stderr fields are set to their default values if they are nil.
-// If the Private field is true, the Stdout field is set to io.Discard.
-// If the Trace field is true, the command line is printed to Stdout.
-func (c *Cmd) Run() error {
-	if c.Trace == nil {
-		c.SetTrace(true)
-	}
-
-	if c.Env == nil {
-		c.Env = os.Environ()
-	}
-
-	if c.Stdout == nil {
-		c.Stdout = os.Stdout
-	}
-
-	if c.Stderr == nil {
-		c.Stderr = os.Stderr
-	}
-
-	if c.Private {
-		c.Stdout = io.Discard
-	}
-
-	if c.TraceWriter == nil {
-		c.TraceWriter = os.Stdout
-	}
-
-	if *c.Trace {
-		fmt.Fprintf(c.TraceWriter, "+ %s\n", strings.Join(c.Args, " "))
-	}
-
-	if err := c.Start(); err != nil {
-		return err
-	}
-
-	return c.Wait()
-}
-
-// SetTrace sets the Trace field of the Cmd to the provided boolean value.
-func (c *Cmd) SetTrace(trace bool) {
-	c.Trace = &trace
-}