chore: include build dep go-paths-helper.

See #305

pkg/paths/readdir.go

@@ -0,0 +1,257 @@
+/*
+ * This file is part of PathsHelper library.
+ *
+ * Copyright 2018-2022 Arduino AG (http://www.arduino.cc/)
+ *
+ * PathsHelper library is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ * As a special exception, you may use this file as part of a free software
+ * library without restriction.  Specifically, if other files instantiate
+ * templates or use macros or inline functions from this file, or you compile
+ * this file and link it with other files to produce an executable, this
+ * file does not by itself cause the resulting executable to be covered by
+ * the GNU General Public License.  This exception does not however
+ * invalidate any other reasons why the executable file might be covered by
+ * the GNU General Public License.
+ */
+
+package paths
+
+import (
+	"errors"
+	"os"
+	"strings"
+)
+
+// ReadDirFilter is a filter for Path.ReadDir and Path.ReadDirRecursive methods.
+// The filter should return true to accept a file or false to reject it.
+type ReadDirFilter func(file *Path) bool
+
+// ReadDir returns a PathList containing the content of the directory
+// pointed by the current Path. The resulting list is filtered by the given filters chained.
+func (p *Path) ReadDir(filters ...ReadDirFilter) (PathList, error) {
+	infos, err := os.ReadDir(p.path)
+	if err != nil {
+		return nil, err
+	}
+
+	accept := func(p *Path) bool {
+		for _, filter := range filters {
+			if !filter(p) {
+				return false
+			}
+		}
+		return true
+	}
+
+	paths := PathList{}
+	for _, info := range infos {
+		path := p.Join(info.Name())
+		if !accept(path) {
+			continue
+		}
+		paths.Add(path)
+	}
+	return paths, nil
+}
+
+// ReadDirRecursive returns a PathList containing the content of the directory
+// and its subdirectories pointed by the current Path
+func (p *Path) ReadDirRecursive() (PathList, error) {
+	return p.ReadDirRecursiveFiltered(nil)
+}
+
+// ReadDirRecursiveFiltered returns a PathList containing the content of the directory
+// and its subdirectories pointed by the current Path, filtered by the given skipFilter
+// and filters:
+//   - `recursionFilter` is a filter that is checked to determine if the subdirectory must
+//     by visited recursively (if the filter rejects the entry, the entry is not visited
+//     but can still be added to the result)
+//   - `filters` are the filters that are checked to determine if the entry should be
+//     added to the resulting PathList
+func (p *Path) ReadDirRecursiveFiltered(recursionFilter ReadDirFilter, filters ...ReadDirFilter) (PathList, error) {
+	var search func(*Path) (PathList, error)
+
+	explored := map[string]bool{}
+	search = func(currPath *Path) (PathList, error) {
+		canonical := currPath.Canonical().path
+		if explored[canonical] {
+			return nil, errors.New("directories symlink loop detected")
+		}
+		explored[canonical] = true
+		defer delete(explored, canonical)
+
+		infos, err := os.ReadDir(currPath.path)
+		if err != nil {
+			return nil, err
+		}
+
+		accept := func(p *Path) bool {
+			for _, filter := range filters {
+				if !filter(p) {
+					return false
+				}
+			}
+			return true
+		}
+
+		paths := PathList{}
+		for _, info := range infos {
+			path := currPath.Join(info.Name())
+
+			if accept(path) {
+				paths.Add(path)
+			}
+
+			if recursionFilter == nil || recursionFilter(path) {
+				if path.IsDir() {
+					subPaths, err := search(path)
+					if err != nil {
+						return nil, err
+					}
+					paths.AddAll(subPaths)
+				}
+			}
+		}
+		return paths, nil
+	}
+
+	return search(p)
+}
+
+// FilterDirectories is a ReadDirFilter that accepts only directories
+func FilterDirectories() ReadDirFilter {
+	return func(path *Path) bool {
+		return path.IsDir()
+	}
+}
+
+// FilterOutDirectories is a ReadDirFilter that rejects all directories
+func FilterOutDirectories() ReadDirFilter {
+	return func(path *Path) bool {
+		return !path.IsDir()
+	}
+}
+
+// FilterNames is a ReadDirFilter that accepts only the given filenames
+func FilterNames(allowedNames ...string) ReadDirFilter {
+	return func(file *Path) bool {
+		for _, name := range allowedNames {
+			if file.Base() == name {
+				return true
+			}
+		}
+		return false
+	}
+}
+
+// FilterOutNames is a ReadDirFilter that rejects the given filenames
+func FilterOutNames(rejectedNames ...string) ReadDirFilter {
+	return func(file *Path) bool {
+		for _, name := range rejectedNames {
+			if file.Base() == name {
+				return false
+			}
+		}
+		return true
+	}
+}
+
+// FilterSuffixes creates a ReadDirFilter that accepts only the given
+// filename suffixes
+func FilterSuffixes(allowedSuffixes ...string) ReadDirFilter {
+	return func(file *Path) bool {
+		for _, suffix := range allowedSuffixes {
+			if strings.HasSuffix(file.String(), suffix) {
+				return true
+			}
+		}
+		return false
+	}
+}
+
+// FilterOutSuffixes creates a ReadDirFilter that rejects all the given
+// filename suffixes
+func FilterOutSuffixes(rejectedSuffixes ...string) ReadDirFilter {
+	return func(file *Path) bool {
+		for _, suffix := range rejectedSuffixes {
+			if strings.HasSuffix(file.String(), suffix) {
+				return false
+			}
+		}
+		return true
+	}
+}
+
+// FilterPrefixes creates a ReadDirFilter that accepts only the given
+// filename prefixes
+func FilterPrefixes(allowedPrefixes ...string) ReadDirFilter {
+	return func(file *Path) bool {
+		name := file.Base()
+		for _, prefix := range allowedPrefixes {
+			if strings.HasPrefix(name, prefix) {
+				return true
+			}
+		}
+		return false
+	}
+}
+
+// FilterOutPrefixes creates a ReadDirFilter that rejects all the given
+// filename prefixes
+func FilterOutPrefixes(rejectedPrefixes ...string) ReadDirFilter {
+	return func(file *Path) bool {
+		name := file.Base()
+		for _, prefix := range rejectedPrefixes {
+			if strings.HasPrefix(name, prefix) {
+				return false
+			}
+		}
+		return true
+	}
+}
+
+// OrFilter creates a ReadDirFilter that accepts all items that are accepted
+// by any (at least one) of the given filters
+func OrFilter(filters ...ReadDirFilter) ReadDirFilter {
+	return func(path *Path) bool {
+		for _, f := range filters {
+			if f(path) {
+				return true
+			}
+		}
+		return false
+	}
+}
+
+// AndFilter creates a ReadDirFilter that accepts all items that are accepted
+// by all the given filters
+func AndFilter(filters ...ReadDirFilter) ReadDirFilter {
+	return func(path *Path) bool {
+		for _, f := range filters {
+			if !f(path) {
+				return false
+			}
+		}
+		return true
+	}
+}
+
+// NotFilter creates a ReadDifFilter that accepts all items rejected by x and viceversa
+func NotFilter(x ReadDirFilter) ReadDirFilter {
+	return func(path *Path) bool {
+		return !x(path)
+	}
+}