refactor(cmd): extract run funcs and add injectable deps for testability

- Introduce newGrokClient and gitRun vars to allow mocking in tests.
- Refactor commit, commitmsg, history, prdescribe, and review cmds into separate run funcs.
- Update docs, lint, and review to use newGrokClient.
- Add comprehensive unit tests in run_test.go covering happy paths, errors, and edge cases.
- Expand grok client tests with SSE server mocks for Stream* methods.

cmd/client.go

@@ -0,0 +1,16 @@
+package cmd
+
+import (
+	"gmgauthier.com/grokkit/internal/git"
+	"gmgauthier.com/grokkit/internal/grok"
+)
+
+// newGrokClient is the factory for the AI client.
+// Tests replace this to inject a mock without making real API calls.
+var newGrokClient = func() grok.AIClient {
+	return grok.NewClient()
+}
+
+// gitRun is the git command runner.
+// Tests replace this to inject controlled git output.
+var gitRun = git.Run

cmd/commit.go

@@ -7,49 +7,49 @@ import (
 	"github.com/fatih/color"
 	"github.com/spf13/cobra"
 	"gmgauthier.com/grokkit/config"
-	"gmgauthier.com/grokkit/internal/git"
-	"gmgauthier.com/grokkit/internal/grok"
 )
 
 var commitCmd = &cobra.Command{
 	Use:   "commit",
 	Short: "Generate message and commit staged changes",
-	Run: func(cmd *cobra.Command, args []string) {
-		diff, err := git.Run([]string{"diff", "--cached", "--no-color"})
-		if err != nil {
-			color.Red("Failed to get staged changes: %v", err)
-			return
-		}
-		if diff == "" {
-			color.Yellow("No staged changes!")
-			return
-		}
-		modelFlag, _ := cmd.Flags().GetString("model")
-		model := config.GetModel("commit", modelFlag)
+	Run:   runCommit,
+}
 
-		client := grok.NewClient()
-		messages := buildCommitMessages(diff)
-		color.Yellow("Generating commit message...")
-		msg := client.Stream(messages, model)
+func runCommit(cmd *cobra.Command, args []string) {
+	diff, err := gitRun([]string{"diff", "--cached", "--no-color"})
+	if err != nil {
+		color.Red("Failed to get staged changes: %v", err)
+		return
+	}
+	if diff == "" {
+		color.Yellow("No staged changes!")
+		return
+	}
+	modelFlag, _ := cmd.Flags().GetString("model")
+	model := config.GetModel("commit", modelFlag)
 
-		color.Cyan("\nProposed commit message:\n%s", msg)
-		var confirm string
-		color.Yellow("Commit with this message? (y/n): ")
-		if _, err := fmt.Scanln(&confirm); err != nil {
-			color.Red("Failed to read input: %v", err)
-			return
-		}
-		if confirm != "y" && confirm != "Y" {
-			color.Yellow("Aborted.")
-			return
-		}
+	client := newGrokClient()
+	messages := buildCommitMessages(diff)
+	color.Yellow("Generating commit message...")
+	msg := client.Stream(messages, model)
 
-		if err := exec.Command("git", "commit", "-m", msg).Run(); err != nil {
-			color.Red("Git commit failed")
-		} else {
-			color.Green("✅ Committed successfully!")
-		}
-	},
+	color.Cyan("\nProposed commit message:\n%s", msg)
+	var confirm string
+	color.Yellow("Commit with this message? (y/n): ")
+	if _, err := fmt.Scanln(&confirm); err != nil {
+		color.Red("Failed to read input: %v", err)
+		return
+	}
+	if confirm != "y" && confirm != "Y" {
+		color.Yellow("Aborted.")
+		return
+	}
+
+	if err := exec.Command("git", "commit", "-m", msg).Run(); err != nil {
+		color.Red("Git commit failed")
+	} else {
+		color.Green("✅ Committed successfully!")
+	}
 }
 
 func buildCommitMessages(diff string) []map[string]string {

cmd/commitmsg.go

@@ -1,37 +1,32 @@
 package cmd
 
 import (
-	"fmt"
-
 	"github.com/fatih/color"
 	"github.com/spf13/cobra"
 	"gmgauthier.com/grokkit/config"
-	"gmgauthier.com/grokkit/internal/git"
-	"gmgauthier.com/grokkit/internal/grok"
 )
 
 var commitMsgCmd = &cobra.Command{
 	Use:   "commit-msg",
 	Short: "Generate conventional commit message from staged changes",
-	Run: func(cmd *cobra.Command, args []string) {
-		diff, err := git.Run([]string{"diff", "--cached", "--no-color"})
-		if err != nil {
-			color.Red("Failed to get staged changes: %v", err)
-			return
-		}
-		if diff == "" {
-			color.Yellow("No staged changes!")
-			return
-		}
-		modelFlag, _ := cmd.Flags().GetString("model")
-		model := config.GetModel("commitmsg", modelFlag)
-
-		client := grok.NewClient()
-		messages := []map[string]string{
-			{"role": "system", "content": "Return ONLY a conventional commit message (type(scope): subject\n\nbody)."},
-			{"role": "user", "content": fmt.Sprintf("Staged changes:\n%s", diff)},
-		}
-		color.Yellow("Generating commit message...")
-		client.Stream(messages, model)
-	},
+	Run:   runCommitMsg,
+}
+
+func runCommitMsg(cmd *cobra.Command, args []string) {
+	diff, err := gitRun([]string{"diff", "--cached", "--no-color"})
+	if err != nil {
+		color.Red("Failed to get staged changes: %v", err)
+		return
+	}
+	if diff == "" {
+		color.Yellow("No staged changes!")
+		return
+	}
+	modelFlag, _ := cmd.Flags().GetString("model")
+	model := config.GetModel("commitmsg", modelFlag)
+
+	client := newGrokClient()
+	messages := buildCommitMessages(diff)
+	color.Yellow("Generating commit message...")
+	client.Stream(messages, model)
 }

cmd/docs.go

@@ -47,13 +47,13 @@ func runDocs(cmd *cobra.Command, args []string) {
 	modelFlag, _ := cmd.Flags().GetString("model")
 	model := config.GetModel("docs", modelFlag)
 
-	client := grok.NewClient()
+	client := newGrokClient()
 	for _, filePath := range args {
 		processDocsFile(client, model, filePath)
 	}
 }
 
-func processDocsFile(client *grok.Client, model, filePath string) {
+func processDocsFile(client grok.AIClient, model, filePath string) {
 	logger.Info("starting docs operation", "file", filePath)
 
 	if _, err := os.Stat(filePath); os.IsNotExist(err) {

cmd/history.go

@@ -4,32 +4,32 @@ import (
 	"github.com/fatih/color"
 	"github.com/spf13/cobra"
 	"gmgauthier.com/grokkit/config"
-	"gmgauthier.com/grokkit/internal/git"
-	"gmgauthier.com/grokkit/internal/grok"
 )
 
 var historyCmd = &cobra.Command{
 	Use:   "history",
 	Short: "Summarize recent git history",
-	Run: func(cmd *cobra.Command, args []string) {
-		log, err := git.Run([]string{"log", "--oneline", "-10"})
-		if err != nil {
-			color.Red("Failed to get git log: %v", err)
-			return
-		}
-		if log == "" {
-			color.Yellow("No commits found.")
-			return
-		}
+	Run:   runHistory,
+}
 
-		modelFlag, _ := cmd.Flags().GetString("model")
-		model := config.GetModel("history", modelFlag)
+func runHistory(cmd *cobra.Command, args []string) {
+	log, err := gitRun([]string{"log", "--oneline", "-10"})
+	if err != nil {
+		color.Red("Failed to get git log: %v", err)
+		return
+	}
+	if log == "" {
+		color.Yellow("No commits found.")
+		return
+	}
 
-		client := grok.NewClient()
-		messages := buildHistoryMessages(log)
-		color.Yellow("Summarizing recent commits...")
-		client.Stream(messages, model)
-	},
+	modelFlag, _ := cmd.Flags().GetString("model")
+	model := config.GetModel("history", modelFlag)
+
+	client := newGrokClient()
+	messages := buildHistoryMessages(log)
+	color.Yellow("Summarizing recent commits...")
+	client.Stream(messages, model)
 }
 
 func buildHistoryMessages(log string) []map[string]string {

cmd/lint.go

@@ -118,7 +118,7 @@ func runLint(cmd *cobra.Command, args []string) {
 	modelFlag, _ := cmd.Flags().GetString("model")
 	model := config.GetModel("lint", modelFlag)
 
-	client := grok.NewClient()
+	client := newGrokClient()
 	messages := buildLintFixMessages(result, string(originalContent))
 	response := client.StreamSilent(messages, model)
 

cmd/prdescribe.go

@@ -6,34 +6,34 @@ import (
 	"github.com/fatih/color"
 	"github.com/spf13/cobra"
 	"gmgauthier.com/grokkit/config"
-	"gmgauthier.com/grokkit/internal/git"
-	"gmgauthier.com/grokkit/internal/grok"
 )
 
 var prDescribeCmd = &cobra.Command{
 	Use:   "pr-describe",
 	Short: "Generate full PR description from current branch",
-	Run: func(cmd *cobra.Command, args []string) {
-		diff, err := git.Run([]string{"diff", "main..HEAD", "--no-color"})
-		if err != nil || diff == "" {
-			diff, err = git.Run([]string{"diff", "origin/main..HEAD", "--no-color"})
-			if err != nil {
-				color.Red("Failed to get branch diff: %v", err)
-				return
-			}
-		}
-		if diff == "" {
-			color.Yellow("No changes on this branch compared to main/origin/main.")
+	Run:   runPRDescribe,
+}
+
+func runPRDescribe(cmd *cobra.Command, args []string) {
+	diff, err := gitRun([]string{"diff", "main..HEAD", "--no-color"})
+	if err != nil || diff == "" {
+		diff, err = gitRun([]string{"diff", "origin/main..HEAD", "--no-color"})
+		if err != nil {
+			color.Red("Failed to get branch diff: %v", err)
 			return
 		}
-		modelFlag, _ := cmd.Flags().GetString("model")
-		model := config.GetModel("prdescribe", modelFlag)
+	}
+	if diff == "" {
+		color.Yellow("No changes on this branch compared to main/origin/main.")
+		return
+	}
+	modelFlag, _ := cmd.Flags().GetString("model")
+	model := config.GetModel("prdescribe", modelFlag)
 
-		client := grok.NewClient()
-		messages := buildPRDescribeMessages(diff)
-		color.Yellow("Writing PR description...")
-		client.Stream(messages, model)
-	},
+	client := newGrokClient()
+	messages := buildPRDescribeMessages(diff)
+	color.Yellow("Writing PR description...")
+	client.Stream(messages, model)
 }
 
 func buildPRDescribeMessages(diff string) []map[string]string {

cmd/review.go

@@ -6,33 +6,33 @@ import (
 	"github.com/fatih/color"
 	"github.com/spf13/cobra"
 	"gmgauthier.com/grokkit/config"
-	"gmgauthier.com/grokkit/internal/git"
-	"gmgauthier.com/grokkit/internal/grok"
 )
 
 var reviewCmd = &cobra.Command{
 	Use:   "review [path]",
 	Short: "Review the current repository or directory",
-	Run: func(cmd *cobra.Command, args []string) {
-		modelFlag, _ := cmd.Flags().GetString("model")
-		model := config.GetModel("review", modelFlag)
+	Run:   runReview,
+}
 
-		client := grok.NewClient()
-		diff, err := git.Run([]string{"diff", "--no-color"})
-		if err != nil {
-			color.Red("Failed to get git diff: %v", err)
-			return
-		}
-		status, err := git.Run([]string{"status", "--short"})
-		if err != nil {
-			color.Red("Failed to get git status: %v", err)
-			return
-		}
+func runReview(cmd *cobra.Command, args []string) {
+	modelFlag, _ := cmd.Flags().GetString("model")
+	model := config.GetModel("review", modelFlag)
 
-		messages := buildReviewMessages(status, diff)
-		color.Yellow("Grok is reviewing the repo...")
-		client.Stream(messages, model)
-	},
+	diff, err := gitRun([]string{"diff", "--no-color"})
+	if err != nil {
+		color.Red("Failed to get git diff: %v", err)
+		return
+	}
+	status, err := gitRun([]string{"status", "--short"})
+	if err != nil {
+		color.Red("Failed to get git status: %v", err)
+		return
+	}
+
+	client := newGrokClient()
+	messages := buildReviewMessages(status, diff)
+	color.Yellow("Grok is reviewing the repo...")
+	client.Stream(messages, model)
 }
 
 func buildReviewMessages(status, diff string) []map[string]string {

cmd/run_test.go

@@ -0,0 +1,453 @@
+package cmd
+
+import (
+	"errors"
+	"os"
+	"testing"
+
+	"github.com/spf13/cobra"
+	"gmgauthier.com/grokkit/internal/grok"
+)
+
+// mockStreamer records calls made to it and returns a canned response.
+type mockStreamer struct {
+	response string
+	calls    int
+}
+
+func (m *mockStreamer) Stream(messages []map[string]string, model string) string {
+	m.calls++
+	return m.response
+}
+
+func (m *mockStreamer) StreamWithTemp(messages []map[string]string, model string, temp float64) string {
+	m.calls++
+	return m.response
+}
+
+func (m *mockStreamer) StreamSilent(messages []map[string]string, model string) string {
+	m.calls++
+	return m.response
+}
+
+// Ensure mockStreamer satisfies the interface at compile time.
+var _ grok.AIClient = (*mockStreamer)(nil)
+
+// withMockClient injects mock and returns a restore func.
+func withMockClient(mock grok.AIClient) func() {
+	orig := newGrokClient
+	newGrokClient = func() grok.AIClient { return mock }
+	return func() { newGrokClient = orig }
+}
+
+// withMockGit injects a fake git runner and returns a restore func.
+func withMockGit(fn func([]string) (string, error)) func() {
+	orig := gitRun
+	gitRun = fn
+	return func() { gitRun = orig }
+}
+
+// testCmd returns a minimal cobra command with the model flag registered.
+func testCmd() *cobra.Command {
+	c := &cobra.Command{}
+	c.Flags().String("model", "", "")
+	return c
+}
+
+// --- runHistory ---
+
+func TestRunHistory(t *testing.T) {
+	t.Run("calls AI with log output", func(t *testing.T) {
+		mock := &mockStreamer{response: "3 commits: feat, fix, chore"}
+		defer withMockClient(mock)()
+		defer withMockGit(func(args []string) (string, error) {
+			return "abc1234 feat: add thing\ndef5678 fix: bug", nil
+		})()
+
+		runHistory(testCmd(), nil)
+
+		if mock.calls != 1 {
+			t.Errorf("expected 1 AI call, got %d", mock.calls)
+		}
+	})
+
+	t.Run("no commits — skips AI", func(t *testing.T) {
+		mock := &mockStreamer{}
+		defer withMockClient(mock)()
+		defer withMockGit(func(args []string) (string, error) {
+			return "", nil
+		})()
+
+		runHistory(testCmd(), nil)
+
+		if mock.calls != 0 {
+			t.Errorf("expected 0 AI calls, got %d", mock.calls)
+		}
+	})
+
+	t.Run("git error — skips AI", func(t *testing.T) {
+		mock := &mockStreamer{}
+		defer withMockClient(mock)()
+		defer withMockGit(func(args []string) (string, error) {
+			return "", errors.New("not a git repo")
+		})()
+
+		runHistory(testCmd(), nil)
+
+		if mock.calls != 0 {
+			t.Errorf("expected 0 AI calls, got %d", mock.calls)
+		}
+	})
+}
+
+// --- runReview ---
+
+func TestRunReview(t *testing.T) {
+	t.Run("reviews with diff and status", func(t *testing.T) {
+		mock := &mockStreamer{response: "looks good"}
+		defer withMockClient(mock)()
+		callCount := 0
+		defer withMockGit(func(args []string) (string, error) {
+			callCount++
+			switch args[0] {
+			case "diff":
+				return "diff content", nil
+			case "status":
+				return "M main.go", nil
+			}
+			return "", nil
+		})()
+
+		runReview(testCmd(), nil)
+
+		if mock.calls != 1 {
+			t.Errorf("expected 1 AI call, got %d", mock.calls)
+		}
+		if callCount != 2 {
+			t.Errorf("expected 2 git calls (diff + status), got %d", callCount)
+		}
+	})
+
+	t.Run("git diff error — skips AI", func(t *testing.T) {
+		mock := &mockStreamer{}
+		defer withMockClient(mock)()
+		defer withMockGit(func(args []string) (string, error) {
+			if args[0] == "diff" {
+				return "", errors.New("git error")
+			}
+			return "", nil
+		})()
+
+		runReview(testCmd(), nil)
+
+		if mock.calls != 0 {
+			t.Errorf("expected 0 AI calls, got %d", mock.calls)
+		}
+	})
+
+	t.Run("git status error — skips AI", func(t *testing.T) {
+		mock := &mockStreamer{}
+		defer withMockClient(mock)()
+		defer withMockGit(func(args []string) (string, error) {
+			if args[0] == "status" {
+				return "", errors.New("git error")
+			}
+			return "diff content", nil
+		})()
+
+		runReview(testCmd(), nil)
+
+		if mock.calls != 0 {
+			t.Errorf("expected 0 AI calls, got %d", mock.calls)
+		}
+	})
+}
+
+// --- runCommit ---
+
+func TestRunCommit(t *testing.T) {
+	t.Run("no staged changes — skips AI", func(t *testing.T) {
+		mock := &mockStreamer{}
+		defer withMockClient(mock)()
+		defer withMockGit(func(args []string) (string, error) {
+			return "", nil
+		})()
+
+		runCommit(testCmd(), nil)
+
+		if mock.calls != 0 {
+			t.Errorf("expected 0 AI calls, got %d", mock.calls)
+		}
+	})
+
+	t.Run("git error — skips AI", func(t *testing.T) {
+		mock := &mockStreamer{}
+		defer withMockClient(mock)()
+		defer withMockGit(func(args []string) (string, error) {
+			return "", errors.New("not a git repo")
+		})()
+
+		runCommit(testCmd(), nil)
+
+		if mock.calls != 0 {
+			t.Errorf("expected 0 AI calls, got %d", mock.calls)
+		}
+	})
+
+	t.Run("with staged changes — calls AI then cancels via stdin", func(t *testing.T) {
+		mock := &mockStreamer{response: "feat(cmd): add thing"}
+		defer withMockClient(mock)()
+		defer withMockGit(func(args []string) (string, error) {
+			return "diff --git a/foo.go b/foo.go\n+func bar() {}", nil
+		})()
+
+		// Pipe "n\n" so the confirmation prompt returns without committing.
+		r, w, _ := os.Pipe()
+		origStdin := os.Stdin
+		os.Stdin = r
+		w.WriteString("n\n")
+		w.Close()
+		defer func() { os.Stdin = origStdin }()
+
+		runCommit(testCmd(), nil)
+
+		if mock.calls != 1 {
+			t.Errorf("expected 1 AI call, got %d", mock.calls)
+		}
+	})
+}
+
+// --- runCommitMsg ---
+
+func TestRunCommitMsg(t *testing.T) {
+	t.Run("no staged changes — skips AI", func(t *testing.T) {
+		mock := &mockStreamer{}
+		defer withMockClient(mock)()
+		defer withMockGit(func(args []string) (string, error) {
+			return "", nil
+		})()
+
+		runCommitMsg(testCmd(), nil)
+
+		if mock.calls != 0 {
+			t.Errorf("expected 0 AI calls, got %d", mock.calls)
+		}
+	})
+
+	t.Run("with staged changes — calls AI and prints message", func(t *testing.T) {
+		mock := &mockStreamer{response: "feat(api): add endpoint"}
+		defer withMockClient(mock)()
+		defer withMockGit(func(args []string) (string, error) {
+			return "diff --git a/api.go b/api.go", nil
+		})()
+
+		runCommitMsg(testCmd(), nil)
+
+		if mock.calls != 1 {
+			t.Errorf("expected 1 AI call, got %d", mock.calls)
+		}
+	})
+}
+
+// --- runPRDescribe ---
+
+func TestRunPRDescribe(t *testing.T) {
+	t.Run("no changes on branch — skips AI", func(t *testing.T) {
+		mock := &mockStreamer{}
+		defer withMockClient(mock)()
+		defer withMockGit(func(args []string) (string, error) {
+			return "", nil // both diff calls return empty
+		})()
+
+		runPRDescribe(testCmd(), nil)
+
+		if mock.calls != 0 {
+			t.Errorf("expected 0 AI calls, got %d", mock.calls)
+		}
+	})
+
+	t.Run("first diff succeeds — calls AI", func(t *testing.T) {
+		mock := &mockStreamer{response: "## PR Title\n\nDescription"}
+		defer withMockClient(mock)()
+		callCount := 0
+		defer withMockGit(func(args []string) (string, error) {
+			callCount++
+			if callCount == 1 {
+				return "diff --git a/foo.go b/foo.go", nil
+			}
+			return "", nil
+		})()
+
+		runPRDescribe(testCmd(), nil)
+
+		if mock.calls != 1 {
+			t.Errorf("expected 1 AI call, got %d", mock.calls)
+		}
+	})
+
+	t.Run("first diff empty, second succeeds — calls AI", func(t *testing.T) {
+		mock := &mockStreamer{response: "PR description"}
+		defer withMockClient(mock)()
+		callCount := 0
+		defer withMockGit(func(args []string) (string, error) {
+			callCount++
+			if callCount == 2 {
+				return "diff --git a/bar.go b/bar.go", nil
+			}
+			return "", nil
+		})()
+
+		runPRDescribe(testCmd(), nil)
+
+		if mock.calls != 1 {
+			t.Errorf("expected 1 AI call, got %d", mock.calls)
+		}
+	})
+
+	t.Run("second diff error — skips AI", func(t *testing.T) {
+		mock := &mockStreamer{}
+		defer withMockClient(mock)()
+		callCount := 0
+		defer withMockGit(func(args []string) (string, error) {
+			callCount++
+			if callCount == 2 {
+				return "", errors.New("no remote")
+			}
+			return "", nil
+		})()
+
+		runPRDescribe(testCmd(), nil)
+
+		if mock.calls != 0 {
+			t.Errorf("expected 0 AI calls, got %d", mock.calls)
+		}
+	})
+}
+
+// --- runLint / processDocsFile (error paths only — linter/file I/O) ---
+
+func TestRunLintFileNotFound(t *testing.T) {
+	// Reset flags to defaults
+	dryRun = false
+	autoFix = false
+
+	// Pass a non-existent file; should return without calling AI.
+	mock := &mockStreamer{}
+	defer withMockClient(mock)()
+
+	runLint(testCmd(), []string{"/nonexistent/path/file.go"})
+
+	if mock.calls != 0 {
+		t.Errorf("expected 0 AI calls for missing file, got %d", mock.calls)
+	}
+}
+
+func TestProcessDocsFileNotFound(t *testing.T) {
+	mock := &mockStreamer{}
+	processDocsFile(mock, "grok-4", "/nonexistent/path/file.go")
+
+	if mock.calls != 0 {
+		t.Errorf("expected 0 AI calls for missing file, got %d", mock.calls)
+	}
+}
+
+func TestProcessDocsFileUnsupportedLanguage(t *testing.T) {
+	// Create a temp file with an unsupported extension.
+	f, err := os.CreateTemp("", "test*.xyz")
+	if err != nil {
+		t.Fatal(err)
+	}
+	f.Close()
+	defer os.Remove(f.Name())
+
+	mock := &mockStreamer{}
+	processDocsFile(mock, "grok-4", f.Name())
+
+	if mock.calls != 0 {
+		t.Errorf("expected 0 AI calls for unsupported language, got %d", mock.calls)
+	}
+}
+
+func TestProcessDocsFilePreviewAndCancel(t *testing.T) {
+	f, err := os.CreateTemp("", "test*.go")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if _, err := f.WriteString("package main\n\nfunc Foo() {}\n"); err != nil {
+		t.Fatal(err)
+	}
+	f.Close()
+	defer os.Remove(f.Name())
+	defer os.Remove(f.Name() + ".bak")
+
+	mock := &mockStreamer{response: "package main\n\n// Foo does nothing.\nfunc Foo() {}\n"}
+
+	origAutoApply := autoApply
+	autoApply = false
+	defer func() { autoApply = origAutoApply }()
+
+	// Pipe "n\n" so confirmation returns without writing.
+	r, w, _ := os.Pipe()
+	origStdin := os.Stdin
+	os.Stdin = r
+	w.WriteString("n\n")
+	w.Close()
+	defer func() { os.Stdin = origStdin }()
+
+	processDocsFile(mock, "grok-4", f.Name())
+
+	if mock.calls != 1 {
+		t.Errorf("expected 1 AI call, got %d", mock.calls)
+	}
+}
+
+func TestProcessDocsFileAutoApply(t *testing.T) {
+	f, err := os.CreateTemp("", "test*.go")
+	if err != nil {
+		t.Fatal(err)
+	}
+	original := "package main\n\nfunc Bar() {}\n"
+	if _, err := f.WriteString(original); err != nil {
+		t.Fatal(err)
+	}
+	f.Close()
+	defer os.Remove(f.Name())
+	defer os.Remove(f.Name() + ".bak")
+
+	// CleanCodeResponse will trim the trailing newline from the AI response.
+	aiResponse := "package main\n\n// Bar does nothing.\nfunc Bar() {}\n"
+	documented := "package main\n\n// Bar does nothing.\nfunc Bar() {}"
+	mock := &mockStreamer{response: aiResponse}
+
+	origAutoApply := autoApply
+	autoApply = true
+	defer func() { autoApply = origAutoApply }()
+
+	processDocsFile(mock, "grok-4", f.Name())
+
+	if mock.calls != 1 {
+		t.Errorf("expected 1 AI call, got %d", mock.calls)
+	}
+	// Verify file was rewritten with documented content.
+	content, _ := os.ReadFile(f.Name())
+	if string(content) != documented {
+		t.Errorf("file content = %q, want %q", string(content), documented)
+	}
+	// Verify backup was created with original content.
+	backup, _ := os.ReadFile(f.Name() + ".bak")
+	if string(backup) != original {
+		t.Errorf("backup content = %q, want %q", string(backup), original)
+	}
+}
+
+func TestRunDocs(t *testing.T) {
+	// runDocs with a missing file: should call processDocsFile which returns early.
+	mock := &mockStreamer{}
+	defer withMockClient(mock)()
+
+	runDocs(testCmd(), []string{"/nonexistent/file.go"})
+
+	if mock.calls != 0 {
+		t.Errorf("expected 0 AI calls for missing file, got %d", mock.calls)
+	}
+}

internal/grok/client_test.go

@@ -1,6 +1,9 @@
 package grok
 
 import (
+	"fmt"
+	"net/http"
+	"net/http/httptest"
 	"os"
 	"testing"
 )
@@ -48,6 +51,81 @@ func TestCleanCodeResponse(t *testing.T) {
 	}
 }
 
+func sseServer(chunks []string) *httptest.Server {
+	return httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "text/event-stream")
+		for _, c := range chunks {
+			fmt.Fprintf(w, "data: {\"choices\":[{\"delta\":{\"content\":%q}}]}\n\n", c)
+		}
+		fmt.Fprintf(w, "data: [DONE]\n\n")
+	}))
+}
+
+func TestStreamSilent(t *testing.T) {
+	srv := sseServer([]string{"Hello", " ", "World"})
+	defer srv.Close()
+
+	client := &Client{APIKey: "test-key", BaseURL: srv.URL}
+	got := client.StreamSilent([]map[string]string{{"role": "user", "content": "hi"}}, "test-model")
+	if got != "Hello World" {
+		t.Errorf("StreamSilent() = %q, want %q", got, "Hello World")
+	}
+}
+
+func TestStream(t *testing.T) {
+	srv := sseServer([]string{"foo", "bar"})
+	defer srv.Close()
+
+	client := &Client{APIKey: "test-key", BaseURL: srv.URL}
+	got := client.Stream([]map[string]string{{"role": "user", "content": "hi"}}, "test-model")
+	if got != "foobar" {
+		t.Errorf("Stream() = %q, want %q", got, "foobar")
+	}
+}
+
+func TestStreamWithTemp(t *testing.T) {
+	srv := sseServer([]string{"response"})
+	defer srv.Close()
+
+	client := &Client{APIKey: "test-key", BaseURL: srv.URL}
+	got := client.StreamWithTemp([]map[string]string{{"role": "user", "content": "hi"}}, "test-model", 0.5)
+	if got != "response" {
+		t.Errorf("StreamWithTemp() = %q, want %q", got, "response")
+	}
+}
+
+func TestStreamDoneSignal(t *testing.T) {
+	// Verifies that [DONE] stops processing and non-content chunks are skipped
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "text/event-stream")
+		fmt.Fprintf(w, "data: {\"choices\":[{\"delta\":{\"content\":\"ok\"}}]}\n\n")
+		fmt.Fprintf(w, "data: [DONE]\n\n")
+		// This line should never be processed
+		fmt.Fprintf(w, "data: {\"choices\":[{\"delta\":{\"content\":\"extra\"}}]}\n\n")
+	}))
+	defer srv.Close()
+
+	client := &Client{APIKey: "test-key", BaseURL: srv.URL}
+	got := client.StreamSilent(nil, "test-model")
+	if got != "ok" {
+		t.Errorf("got %q, want %q", got, "ok")
+	}
+}
+
+func TestStreamEmptyResponse(t *testing.T) {
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "text/event-stream")
+		fmt.Fprintf(w, "data: [DONE]\n\n")
+	}))
+	defer srv.Close()
+
+	client := &Client{APIKey: "test-key", BaseURL: srv.URL}
+	got := client.StreamSilent(nil, "test-model")
+	if got != "" {
+		t.Errorf("got %q, want empty string", got)
+	}
+}
+
 func TestNewClient(t *testing.T) {
 	// Save and restore env
 	oldKey := os.Getenv("XAI_API_KEY")