Simplify walker to use PatternMatcher instead of custom matching

walker.go

@@ -10,7 +10,6 @@ import (
 
 	"github.com/docker/docker/pkg/fileutils"
 	"github.com/pkg/errors"
-	"github.com/tonistiigi/fsutil/prefix"
 	"github.com/tonistiigi/fsutil/types"
 )
 
@@ -36,20 +35,15 @@ func Walk(ctx context.Context, p string, opt *WalkOpt, fn filepath.WalkFunc) err
 		return errors.WithStack(&os.PathError{Op: "walk", Path: root, Err: syscall.ENOTDIR})
 	}
 
-	var pm *fileutils.PatternMatcher
-	if opt != nil && opt.ExcludePatterns != nil {
-		pm, err = fileutils.NewPatternMatcher(opt.ExcludePatterns)
-		if err != nil {
-			return errors.Wrapf(err, "invalid excludepatterns: %s", opt.ExcludePatterns)
-		}
-	}
+	var (
+		includePatterns []string
+		includeMatcher  *fileutils.PatternMatcher
+		excludeMatcher  *fileutils.PatternMatcher
+	)
 
-	var includePatterns []string
 	if opt != nil && opt.IncludePatterns != nil {
 		includePatterns = make([]string, len(opt.IncludePatterns))
-		for k := range opt.IncludePatterns {
-			includePatterns[k] = filepath.Clean(opt.IncludePatterns[k])
-		}
+		copy(includePatterns, opt.IncludePatterns)
 	}
 	if opt != nil && opt.FollowPaths != nil {
 		targets, err := FollowLinks(p, opt.FollowPaths)
@@ -61,13 +55,32 @@ func Walk(ctx context.Context, p string, opt *WalkOpt, fn filepath.WalkFunc) err
 			includePatterns = dedupePaths(includePatterns)
 		}
 	}
+	if len(includePatterns) != 0 {
+		includeMatcher, err = fileutils.NewPatternMatcher(includePatterns)
+		if err != nil {
+			return errors.Wrapf(err, "invalid includepatterns: %s", opt.IncludePatterns)
+		}
+	}
 
-	var (
-		lastIncludedDir string
+	if opt != nil && opt.ExcludePatterns != nil {
+		excludeMatcher, err = fileutils.NewPatternMatcher(opt.ExcludePatterns)
+		if err != nil {
+			return errors.Wrapf(err, "invalid excludepatterns: %s", opt.ExcludePatterns)
+		}
+	}
 
-		parentDirs           []string // used only for exclude handling
-		parentMatchedExclude []bool
-	)
+	type visitedDir struct {
+		fi             os.FileInfo
+		path           string
+		origpath       string
+		pathWithSep    string
+		matchedInclude bool
+		matchedExclude bool
+		calledFn       bool
+	}
+
+	// used only for include/exclude handling
+	var parentDirs []visitedDir
 
 	seenFiles := make(map[uint64]string)
 	return filepath.Walk(root, func(path string, fi os.FileInfo, err error) (retErr error) {
@@ -90,87 +103,84 @@ func Walk(ctx context.Context, p string, opt *WalkOpt, fn filepath.WalkFunc) err
 			return nil
 		}
 
-		if opt != nil {
-			if includePatterns != nil {
-				skip := false
-				if lastIncludedDir != "" {
-					if strings.HasPrefix(path, lastIncludedDir+string(filepath.Separator)) {
-						skip = true
-					}
-				}
+		var dir visitedDir
 
-				if !skip {
-					matched := false
-					partial := true
-					for _, pattern := range includePatterns {
-						if ok, p := prefix.Match(pattern, path, false); ok {
-							matched = true
-							if !p {
-								partial = false
-								break
-							}
-						}
-					}
-					if !matched {
-						if fi.IsDir() {
-							return filepath.SkipDir
-						}
-						return nil
-					}
-					if !partial && fi.IsDir() {
-						lastIncludedDir = path
-					}
+		if includeMatcher != nil || excludeMatcher != nil {
+			for len(parentDirs) != 0 {
+				lastParentDir := parentDirs[len(parentDirs)-1].pathWithSep
+				if strings.HasPrefix(path, lastParentDir) {
+					break
 				}
+				parentDirs = parentDirs[:len(parentDirs)-1]
 			}
-			if pm != nil {
-				for len(parentMatchedExclude) != 0 {
-					lastParentDir := parentDirs[len(parentDirs)-1]
-					if strings.HasPrefix(path, lastParentDir) {
-						break
-					}
-					parentDirs = parentDirs[:len(parentDirs)-1]
-					parentMatchedExclude = parentMatchedExclude[:len(parentMatchedExclude)-1]
-				}
 
-				var m bool
-				if len(parentMatchedExclude) != 0 {
-					m, err = pm.MatchesUsingParentResult(path, parentMatchedExclude[len(parentMatchedExclude)-1])
-				} else {
-					m, err = pm.MatchesOrParentMatches(path)
+			if fi.IsDir() {
+				dir = visitedDir{
+					fi:          fi,
+					path:        path,
+					origpath:    origpath,
+					pathWithSep: path + string(filepath.Separator),
 				}
-				if err != nil {
-					return errors.Wrap(err, "failed to match excludepatterns")
+			}
+		}
+
+		skip := false
+
+		if includeMatcher != nil {
+			var parentMatchedInclude *bool
+			if len(parentDirs) != 0 {
+				parentMatchedInclude = &parentDirs[len(parentDirs)-1].matchedInclude
+			}
+			m, err := matchesPatterns(includeMatcher, path, parentMatchedInclude)
+			if err != nil {
+				return errors.Wrap(err, "failed to match includepatterns")
+			}
+
+			if fi.IsDir() {
+				dir.matchedInclude = m
+			}
+
+			if !m {
+				skip = true
+			}
+		}
+
+		if excludeMatcher != nil {
+			var parentMatchedExclude *bool
+			if len(parentDirs) != 0 {
+				parentMatchedExclude = &parentDirs[len(parentDirs)-1].matchedExclude
+			}
+			m, err := matchesPatterns(excludeMatcher, path, parentMatchedExclude)
+			if err != nil {
+				return errors.Wrap(err, "failed to match excludepatterns")
+			}
+
+			if fi.IsDir() {
+				dir.matchedExclude = m
+			}
+
+			if m {
+				if fi.IsDir() && !excludeMatcher.Exclusions() {
+					return filepath.SkipDir
 				}
+				skip = true
+			}
+		}
 
-				var dirSlash string
+		if includeMatcher != nil || excludeMatcher != nil {
+			defer func() {
 				if fi.IsDir() {
-					dirSlash = path + string(filepath.Separator)
-					parentDirs = append(parentDirs, dirSlash)
-					parentMatchedExclude = append(parentMatchedExclude, m)
+					parentDirs = append(parentDirs, dir)
 				}
+			}()
+		}
 
-				if m {
-					if fi.IsDir() {
-						if !pm.Exclusions() {
-							return filepath.SkipDir
-						}
-						for _, pat := range pm.Patterns() {
-							if !pat.Exclusion() {
-								continue
-							}
-							patStr := pat.String() + string(filepath.Separator)
-							if strings.HasPrefix(patStr, dirSlash) {
-								goto passedFilter
-							}
-						}
-						return filepath.SkipDir
-					}
-					return nil
-				}
-			}
+		if skip {
+			return nil
 		}
 
-	passedFilter:
+		dir.calledFn = true
+
 		stat, err := mkstat(origpath, path, fi, seenFiles)
 		if err != nil {
 			return err
@@ -185,6 +195,31 @@ func Walk(ctx context.Context, p string, opt *WalkOpt, fn filepath.WalkFunc) err
 					return nil
 				}
 			}
+			for i, parentDir := range parentDirs {
+				if parentDir.calledFn {
+					continue
+				}
+				parentStat, err := mkstat(parentDir.origpath, parentDir.path, parentDir.fi, seenFiles)
+				if err != nil {
+					return err
+				}
+
+				select {
+				case <-ctx.Done():
+					return ctx.Err()
+				default:
+				}
+				if opt != nil && opt.Map != nil {
+					if allowed := opt.Map(parentStat.Path, parentStat); !allowed {
+						continue
+					}
+				}
+
+				if err := fn(parentStat.Path, &StatInfo{parentStat}, nil); err != nil {
+					return err
+				}
+				parentDirs[i].calledFn = true
+			}
 			if err := fn(stat.Path, &StatInfo{stat}, nil); err != nil {
 				return err
 			}
@@ -193,6 +228,23 @@ func Walk(ctx context.Context, p string, opt *WalkOpt, fn filepath.WalkFunc) err
 	})
 }
 
+func matchesPatterns(pm *fileutils.PatternMatcher, path string, parentMatched *bool) (bool, error) {
+	var (
+		m   bool
+		err error
+	)
+	if parentMatched != nil {
+		m, err = pm.MatchesUsingParentResult(path, *parentMatched)
+	} else {
+		m, err = pm.MatchesOrParentMatches(path)
+	}
+	if err != nil {
+		return false, err
+	}
+
+	return m, nil
+}
+
 type StatInfo struct {
 	*types.Stat
 }