add cli testing

Signed-off-by: Alex Goodman <alex.goodman@anchore.com>

test/cli/root_cmd_test.go

@@ -0,0 +1,91 @@
+package cli
+
+import (
+	"strings"
+	"testing"
+
+	"github.com/sergi/go-diff/diffmatchpatch"
+)
+
+func TestRootCmdAliasesToPackagesSubcommand(t *testing.T) {
+	request := "docker-archive:" + getFixtureImage(t, "image-pkg-coverage")
+	deprecationWarning := "The root command is deprecated"
+
+	_, aliasStdout, aliasStderr := runSyftCommand(t, nil, request)
+
+	if !strings.Contains(aliasStderr, deprecationWarning) {
+		t.Errorf("missing root-packages alias deprecation warning")
+	}
+
+	_, pkgsStdout, pkgsStderr := runSyftCommand(t, nil, "packages", request)
+
+	if strings.Contains(pkgsStderr, deprecationWarning) {
+		t.Errorf("packages command should not have deprecation warning")
+	}
+
+	if aliasStdout != pkgsStdout {
+		t.Errorf("packages and root command should have same report output but do not!")
+		dmp := diffmatchpatch.New()
+		diffs := dmp.DiffMain(aliasStdout, pkgsStdout, true)
+		t.Error(dmp.DiffPrettyText(diffs))
+	}
+}
+
+func TestPersistentFlags(t *testing.T) {
+	request := "docker-archive:" + getFixtureImage(t, "image-pkg-coverage")
+
+	tests := []struct {
+		name       string
+		args       []string
+		env        map[string]string
+		assertions []traitAssertion
+	}{
+		{
+			name: "quiet-flag",
+			// note: the root command will always show the deprecation warning, so the packages command is used instead
+			args: []string{"packages", "-q", request},
+			assertions: []traitAssertion{
+				func(tb testing.TB, stdout, stderr string, rc int) {
+					// ensure there is no status
+					if len(stderr) != 0 {
+						tb.Errorf("should have seen no stderr output, got %d bytes", len(stderr))
+					}
+					// ensure there is still a report
+					if len(stdout) == 0 {
+						tb.Errorf("should have seen a report on stdout, got nothing")
+					}
+				},
+			},
+		},
+		{
+			name: "info-log-flag",
+			args: []string{"-v", request},
+			assertions: []traitAssertion{
+				assertLoggingLevel("info"),
+				assertSuccessfulReturnCode,
+			},
+		},
+		{
+			name: "debug-log-flag",
+			args: []string{"-vv", request},
+			assertions: []traitAssertion{
+				assertLoggingLevel("debug"),
+				assertSuccessfulReturnCode,
+			},
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			cmd, stdout, stderr := runSyftCommand(t, test.env, test.args...)
+			for _, traitFn := range test.assertions {
+				traitFn(t, stdout, stderr, cmd.ProcessState.ExitCode())
+			}
+			if t.Failed() {
+				t.Log("STDOUT:\n", stdout)
+				t.Log("STDERR:\n", stderr)
+				t.Log("COMMAND:", strings.Join(cmd.Args, " "))
+			}
+		})
+	}
+}