feat: add executor that spawns claude and parses JSON result

internal/exec/executor_test.go

@@ -0,0 +1,75 @@
+package exec_test
+
+import (
+	"context"
+	"os"
+	"path/filepath"
+	"testing"
+	"time"
+
+	iexec "github.com/mathiasbq/supervisor/internal/exec"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+// fakeClaudePath writes a shell script that prints fixed output and returns its path.
+func fakeClaudePath(t *testing.T, output string, exitCode int) string {
+	t.Helper()
+	dir := t.TempDir()
+	script := filepath.Join(dir, "claude")
+	var content string
+	if exitCode != 0 {
+		content = "#!/bin/sh\necho 'error' >&2\nexit 1\n"
+	} else {
+		content = "#!/bin/sh\necho '" + output + "'\n"
+	}
+	require.NoError(t, os.WriteFile(script, []byte(content), 0755))
+	return script
+}
+
+func TestExecutorParsesValidResult(t *testing.T) {
+	validJSON := `{"status":"pass","phase":"red","skill":"tdd","file_path":"/tmp/x_test.go","runner_output":"FAIL","verified":true,"model_used":"self","message":"ok"}`
+	claude := fakeClaudePath(t, validJSON, 0)
+
+	ex := iexec.New(iexec.Config{
+		ClaudeBinary: claude,
+		SystemPrompt: "you are a supervisor",
+		Timeout:      5 * time.Second,
+	})
+
+	result, err := ex.Run(context.Background(), iexec.Request{
+		SkillPrompt: "tdd rules",
+		TaskPrompt:  "run red phase",
+	})
+	require.NoError(t, err)
+	assert.Equal(t, "pass", result.Status)
+	assert.True(t, result.Verified)
+}
+
+func TestExecutorReturnsErrorOnNonZeroExit(t *testing.T) {
+	claude := fakeClaudePath(t, "", 1)
+
+	ex := iexec.New(iexec.Config{
+		ClaudeBinary: claude,
+		SystemPrompt: "you are a supervisor",
+		Timeout:      5 * time.Second,
+	})
+
+	_, err := ex.Run(context.Background(), iexec.Request{TaskPrompt: "fail"})
+	assert.Error(t, err)
+}
+
+func TestExecutorTimesOut(t *testing.T) {
+	dir := t.TempDir()
+	script := filepath.Join(dir, "claude")
+	require.NoError(t, os.WriteFile(script, []byte("#!/bin/sh\nsleep 60\n"), 0755))
+
+	ex := iexec.New(iexec.Config{
+		ClaudeBinary: script,
+		SystemPrompt: "you are a supervisor",
+		Timeout:      100 * time.Millisecond,
+	})
+
+	_, err := ex.Run(context.Background(), iexec.Request{TaskPrompt: "slow"})
+	assert.ErrorContains(t, err, "timeout")
+}