test: improve test coverage across multiple packages

- Added comprehensive tests for options package (0% → 76.9%)
- Added tests for internal/archivista package (0% → 100%)
- Enhanced cmd package test coverage (33.3% → 75.8%)
- Modified root.go to allow for testing the Execute function
- Added tests for previously untested functions
- Implemented mock patterns for external dependencies
- Used table-driven tests for comprehensive test cases

Overall project coverage improved from 24.5% to 66.1% (+41.6%)

Author: Cole Kennedy

cmd/attestors_test.go

@@ -0,0 +1,114 @@
+// Copyright 2022 The Witness Contributors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package cmd
+
+import (
+	"context"
+	"io"
+	"os"
+	"testing"
+
+	"github.com/in-toto/go-witness/attestation"
+	"github.com/stretchr/testify/require"
+)
+
+func Test_AttestorsCmd(t *testing.T) {
+	cmd := AttestorsCmd()
+	require.NotNil(t, cmd)
+	require.Equal(t, "attestors", cmd.Use)
+	require.Equal(t, 2, len(cmd.Commands()))
+}
+
+func Test_ListCmd(t *testing.T) {
+	cmd := ListCmd()
+	require.NotNil(t, cmd)
+	require.Equal(t, "list", cmd.Use)
+}
+
+func Test_SchemaCmd(t *testing.T) {
+	cmd := SchemaCmd()
+	require.NotNil(t, cmd)
+	require.Equal(t, "schema", cmd.Use)
+}
+
+func Test_runList(t *testing.T) {
+	// Redirect stdout to capture output
+	oldStdout := os.Stdout
+	r, w, _ := os.Pipe()
+	os.Stdout = w
+
+	defer func() {
+		os.Stdout = oldStdout
+	}()
+
+	err := runList(context.Background())
+	require.NoError(t, err)
+
+	// Close the writer to get all output
+	w.Close()
+	
+	// Read the output but we don't need to verify its contents
+	// as we just need to ensure it executes without error
+	_, _ = io.ReadAll(r)
+}
+
+func Test_runSchema(t *testing.T) {
+	t.Run("without arguments", func(t *testing.T) {
+		err := runSchema(context.Background(), []string{})
+		require.Error(t, err)
+		require.Contains(t, err.Error(), "You must specify an attestor")
+	})
+
+	t.Run("with too many arguments", func(t *testing.T) {
+		err := runSchema(context.Background(), []string{"one", "two"})
+		require.Error(t, err)
+		require.Contains(t, err.Error(), "You can only get one attestor")
+	})
+
+	t.Run("with invalid attestor", func(t *testing.T) {
+		err := runSchema(context.Background(), []string{"invalid-attestor"})
+		require.Error(t, err)
+		require.Contains(t, err.Error(), "Error getting attestor")
+	})
+
+	t.Run("with valid attestor", func(t *testing.T) {
+		// Get a valid attestor name
+		entries := attestation.RegistrationEntries()
+		if len(entries) == 0 {
+			t.Skip("No attestors registered, skipping test")
+			return
+		}
+
+		validAttestor := entries[0].Factory().Name()
+
+		// Redirect stdout to capture output
+		oldStdout := os.Stdout
+		r, w, _ := os.Pipe()
+		os.Stdout = w
+
+		defer func() {
+			os.Stdout = oldStdout
+		}()
+
+		err := runSchema(context.Background(), []string{validAttestor})
+		require.NoError(t, err)
+
+		// Close the writer to get all output
+		w.Close()
+		
+		// Read the output but we don't need to verify its contents
+		_, _ = io.ReadAll(r)
+	})
+}

cmd/completion_test.go

@@ -0,0 +1,106 @@
+// Copyright 2022 The Witness Contributors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package cmd
+
+import (
+	"bytes"
+	"io"
+	"os"
+	"testing"
+
+	"github.com/spf13/cobra"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func Test_CompletionCmd(t *testing.T) {
+	cmd := CompletionCmd()
+	require.NotNil(t, cmd)
+	assert.Equal(t, "completion [bash|zsh|fish|powershell]", cmd.Use)
+	assert.Equal(t, true, cmd.DisableFlagsInUseLine)
+	assert.Equal(t, true, cmd.DisableAutoGenTag)
+	
+	// Test that ValidArgs contains the expected values
+	expectedValidArgs := []string{"bash", "zsh", "fish", "powershell"}
+	assert.Equal(t, expectedValidArgs, cmd.ValidArgs)
+	
+	// Test that Args validation works as expected
+	assert.NoError(t, cmd.Args(cmd, []string{"bash"}))
+	assert.NoError(t, cmd.Args(cmd, []string{"zsh"}))
+	assert.NoError(t, cmd.Args(cmd, []string{"fish"}))
+	assert.NoError(t, cmd.Args(cmd, []string{"powershell"}))
+	assert.Error(t, cmd.Args(cmd, []string{"invalid"}))
+	assert.Error(t, cmd.Args(cmd, []string{}))
+	assert.Error(t, cmd.Args(cmd, []string{"bash", "extra"}))
+}
+
+func Test_CompletionCmd_Run(t *testing.T) {
+	tests := []struct {
+		name     string
+		shell    string
+		contains string // just check for a common string that should be in all completions
+	}{
+		{
+			name:     "bash",
+			shell:    "bash",
+			contains: "# bash completion",
+		},
+		{
+			name:     "zsh",
+			shell:    "zsh",
+			contains: "#compdef",
+		},
+		{
+			name:     "fish",
+			shell:    "fish",
+			contains: "# fish completion",
+		},
+		{
+			name:     "powershell",
+			shell:    "powershell",
+			contains: "Register-ArgumentCompleter",
+		},
+	}
+	
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			// Create a root command for completions to work with
+			rootCmd := &cobra.Command{Use: "witness"}
+			
+			// Add the completion command to the root
+			completionCmd := CompletionCmd()
+			rootCmd.AddCommand(completionCmd)
+			
+			// Redirect stdout to capture output
+			oldStdout := os.Stdout
+			r, w, _ := os.Pipe()
+			os.Stdout = w
+			
+			// Execute the completion command directly
+			completionCmd.Run(completionCmd, []string{tc.shell})
+			
+			// Restore stdout
+			w.Close()
+			os.Stdout = oldStdout
+			
+			// Read the captured output
+			var buf bytes.Buffer
+			io.Copy(&buf, r)
+			
+			// Check the output contains the expected content
+			assert.Contains(t, buf.String(), tc.contains)
+		})
+	}
+}