package matching

import (
	"os"
	"strings"
	"testing"
)

func readFile(t *testing.T, name string) string {
	t.Helper()
	b, err := os.ReadFile(name)
	if err != nil {
		t.Fatalf("read %s: %v", name, err)
	}
	return string(b)
}

// functionBody bounds one function's text for the structural guards. Crude, and sufficient: it only has to
// find where a function ends, and gofmt guarantees a top level func starts at column zero.
func functionBody(src, signature string) string {
	i := strings.Index(src, signature)
	if i < 0 {
		return ""
	}
	rest := src[i+len(signature):]
	if j := strings.Index(rest, "\nfunc "); j >= 0 {
		return rest[:j]
	}
	return rest
}