internal/server/delegation/delegation_doc_test.go

Ref: main v0.0.5   Size: 2.3 KiB   History

package delegation

import (
	"os"
	"path/filepath"
	"runtime"
	"strings"
	"testing"
	"time"
)

// TestDocsMatchThePendingGrace keeps the prose from drifting from the constant.
// defaultPendingGrace is the only place the grace is decided, and three surfaces
// restate it in words for readers who never see the source: the delegation
// section of docs/mcp.md, the delegate_begin tool description, and the route
// summary that becomes the OpenAPI spec and the TypeScript types. Each says the
// number exactly once, so this reads the real files and fails if the constant
// moves without them, rather than letting the promise quietly lie in three
// places at once.
func TestDocsMatchThePendingGrace(t *testing.T) {
	want := graceProse(t, defaultPendingGrace)
	for _, rel := range []string{
		"docs/mcp.md",
		"internal/mcpserver/server.go",
		"internal/server/api/routes.go",
	} {
		if !strings.Contains(string(readRepoFile(t, rel)), want) {
			t.Errorf("%s no longer tells a caller a begin is abandoned after %q — update the wording "+
				"there and in the other two sites when defaultPendingGrace changes", rel, want)
		}
	}
}

// graceProse renders a grace the way the three surfaces say it in English. Only
// the durations the prose has words for are listed: changing the constant to
// anything else fails here first, which is the prompt to decide the wording
// once and then let the test above find every site that needs it.
func graceProse(t *testing.T, d time.Duration) string {
	t.Helper()
	if d == time.Hour {
		return "an hour"
	}
	t.Fatalf("no documented wording for a grace of %s — write it here, then update the sites this test reads", d)
	return ""
}

// readRepoFile reads a path relative to the repo root, found by walking up from
// this source file to the go.mod. Tests run from the package directory, so the
// repo root is not the working directory.
func readRepoFile(t *testing.T, rel string) []byte {
	t.Helper()
	_, self, _, ok := runtime.Caller(0)
	if !ok {
		t.Fatal("runtime.Caller failed")
	}
	dir := filepath.Dir(self)
	for {
		if _, err := os.Stat(filepath.Join(dir, "go.mod")); err == nil {
			break
		}
		parent := filepath.Dir(dir)
		if parent == dir {
			t.Fatal("could not find repo root (go.mod) above " + self)
		}
		dir = parent
	}
	b, err := os.ReadFile(filepath.Join(dir, rel))
	if err != nil {
		t.Fatal(err)
	}
	return b
}