Fixed lint issues and missing documentation

internal/mock/findATender/store.go

@@ -4,6 +4,7 @@ import (
 	"bufio"
 	"bytes"
 	"encoding/json"
+	"errors"
 	"fmt"
 	"log"
 	"math/rand"
@@ -69,14 +70,14 @@ func OpenStore(path string) (*Store, error) {
 // readReleases reads the releases stored at path, skipping lines that are
 // blank or can't be decoded. A missing file holds no releases.
 func readReleases(path string) ([]ocds.Release, error) {
-	in, err := os.Open(path)
+	in, err := os.Open(filepath.Clean(path))
 	if os.IsNotExist(err) {
 		return nil, nil
 	}
 	if err != nil {
 		return nil, err
 	}
-	defer in.Close()
+	defer in.Close() //nolint:errcheck // read only
 
 	var releases []ocds.Release
 	sc := bufio.NewScanner(in)
@@ -103,7 +104,7 @@ func readReleases(path string) ([]ocds.Release, error) {
 // mid-write, it ends the partial record so the next one starts on a fresh
 // line.
 func openForAppend(path string) (*os.File, error) {
-	f, err := os.OpenFile(path, os.O_CREATE|os.O_RDWR|os.O_APPEND, 0o600)
+	f, err := os.OpenFile(filepath.Clean(path), os.O_CREATE|os.O_RDWR|os.O_APPEND, 0o600)
 	if err != nil {
 		return nil, err
 	}
@@ -111,8 +112,7 @@ func openForAppend(path string) (*os.File, error) {
 		last := make([]byte, 1)
 		if _, err := f.ReadAt(last, st.Size()-1); err == nil && last[0] != '\n' {
 			if _, err := f.Write([]byte("\n")); err != nil {
-				f.Close()
-				return nil, fmt.Errorf("repairing %s: %w", path, err)
+				return nil, errors.Join(fmt.Errorf("repairing %s: %w", path, err), f.Close())
 			}
 		}
 	}
@@ -166,8 +166,9 @@ func (s *Store) Sync() error {
 	return s.f.Sync()
 }
 
-// A date earlier than the newest stored release (for example after a clock
-// change) is moved up so the order stays valid.
+// append stores r, syncing the file to disk if sync is true. A date earlier
+// than the newest stored release (for example after a clock change) is moved
+// up so the order stays valid.
 func (s *Store) append(r ocds.Release, sync bool) error {
 	s.mu.Lock()
 	defer s.mu.Unlock()
@@ -224,12 +225,14 @@ func (s *Store) Last() (time.Time, bool) {
 	return s.times[len(s.times)-1], true
 }
 
+// Len returns the number of stored releases.
 func (s *Store) Len() int {
 	s.mu.RLock()
 	defer s.mu.RUnlock()
 	return len(s.releases)
 }
 
+// HasOCID reports whether any release of the procedure ocid is stored.
 func (s *Store) HasOCID(ocid string) bool {
 	s.mu.RLock()
 	defer s.mu.RUnlock()
@@ -261,6 +264,7 @@ func (s *Store) RandomOpen(r *rand.Rand, since time.Time) (ocds.Release, bool) {
 	return ocds.Release{}, false
 }
 
+// Close closes the store's file. The store must not be used afterwards.
 func (s *Store) Close() error {
 	s.mu.Lock()
 	defer s.mu.Unlock()