pulumi/sdk/go/common/util/fsutil/walkup.go

84 lines
2.2 KiB
Go

// Copyright 2016-2018, Pulumi Corporation.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package fsutil
import (
"fmt"
"os"
"path/filepath"
)
// WalkUp walks each file in path, passing the full path to `walkFn`. If walkFn returns true,
// this method returns the path that was passed to walkFn. Before visiting the parent directory,
// visitParentFn is called, if that returns false, WalkUp stops its search
func WalkUp(path string, walkFn func(string) bool, visitParentFn func(string) bool) (string, error) {
if visitParentFn == nil {
visitParentFn = func(dir string) bool { return true }
}
// This needs to be an absolute path otherwise we will get stuck in an infinite loop of the parent
// directory of "." being ".".
path, err := filepath.Abs(path)
if err != nil {
return "", fmt.Errorf("abs: %w", err)
}
curr := pathDir(path)
for {
// visit each file
files, err := os.ReadDir(curr)
if err != nil {
return "", err
}
for _, file := range files {
name := file.Name()
path := filepath.Join(curr, name)
if walkFn(path) {
return path, nil
}
}
// If we are at the root, stop walking
if isTop(curr) {
break
}
if !visitParentFn(curr) {
break
}
// visit the parent
curr = filepath.Dir(curr)
}
return "", nil
}
// pathDir returns the nearest directory to the given path (identity if a directory; parent otherwise).
func pathDir(path string) string {
// If the path is a file, we want the directory it is in
info, err := os.Stat(path)
if err != nil || info.IsDir() {
return path
}
return filepath.Dir(path)
}
// isTop returns true if the path represents the top of the filesystem.
func isTop(path string) bool {
return os.IsPathSeparator(path[len(path)-1])
}