Add cli output handlers (#3660)

Co-authored-by: Anbraten <6918444+anbraten@users.noreply.github.com>

cli/pipeline/pipeline_test.go

@@ -0,0 +1,86 @@
+package pipeline
+
+import (
+	"bytes"
+	"io"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/urfave/cli/v2"
+
+	"go.woodpecker-ci.org/woodpecker/v2/cli/common"
+	"go.woodpecker-ci.org/woodpecker/v2/woodpecker-go/woodpecker"
+)
+
+func TestPipelineOutput(t *testing.T) {
+	tests := []struct {
+		name     string
+		args     []string
+		expected string
+		wantErr  bool
+	}{
+		{
+			name:     "table output with default columns",
+			args:     []string{},
+			expected: "NUMBER  STATUS   EVENT  BRANCH  COMMIT  AUTHOR\n1       success  push   main    abcdef  John Doe\n",
+		},
+		{
+			name:     "table output with custom columns",
+			args:     []string{"output", "--output", "table=Number,Status,Branch"},
+			expected: "NUMBER  STATUS   BRANCH\n1       success  main\n",
+		},
+		{
+			name:     "table output with no header",
+			args:     []string{"output", "--output-no-headers"},
+			expected: "1  success  push  main  abcdef  John Doe\n",
+		},
+		{
+			name:     "go-template output",
+			args:     []string{"output", "--output", "go-template={{range . }}{{.Number}} {{.Status}} {{.Branch}}{{end}}"},
+			expected: "1 success main\n",
+		},
+		{
+			name:    "invalid go-template",
+			args:    []string{"output", "--output", "go-template={{.InvalidField}}"},
+			wantErr: true,
+		},
+	}
+
+	pipelines := []woodpecker.Pipeline{
+		{
+			Number: 1,
+			Status: "success",
+			Event:  "push",
+			Branch: "main",
+			Commit: "abcdef",
+			Author: "John Doe",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			app := &cli.App{Writer: io.Discard}
+			c := cli.NewContext(app, nil, nil)
+
+			command := &cli.Command{}
+			command.Name = "output"
+			command.Flags = common.OutputFlags("table")
+			command.Action = func(c *cli.Context) error {
+				var buf bytes.Buffer
+				err := pipelineOutput(c, pipelines, &buf)
+
+				if tt.wantErr {
+					assert.Error(t, err)
+					return nil
+				}
+
+				assert.NoError(t, err)
+				assert.Equal(t, tt.expected, buf.String())
+
+				return nil
+			}
+
+			_ = command.Run(c, tt.args...)
+		})
+	}
+}