github.com/cloudfoundry/libcfbuildpack@v1.91.23/test/be_a_symlink.go (about)

     1  /*
     2   * Copyright 2018-2020 the original author or authors.
     3   *
     4   * Licensed under the Apache License, Version 2.0 (the "License");
     5   * you may not use this file except in compliance with the License.
     6   * You may obtain a copy of the License at
     7   *
     8   *      https://www.apache.org/licenses/LICENSE-2.0
     9   *
    10   * Unless required by applicable law or agreed to in writing, software
    11   * distributed under the License is distributed on an "AS IS" BASIS,
    12   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13   * See the License for the specific language governing permissions and
    14   * limitations under the License.
    15   */
    16  
    17  package test
    18  
    19  import (
    20  	"fmt"
    21  	"os"
    22  
    23  	"github.com/onsi/gomega/types"
    24  )
    25  
    26  // BeASymlink asserts that a file is a symlink and the link points to a given target.
    27  func BeASymlink(target string) types.GomegaMatcher {
    28  	return &beASymlinkMatcher{
    29  		target: target,
    30  	}
    31  }
    32  
    33  type beASymlinkMatcher struct {
    34  	target string
    35  }
    36  
    37  func (m *beASymlinkMatcher) Match(actual interface{}) (bool, error) {
    38  	path, ok := actual.(string)
    39  	if !ok {
    40  		return false, fmt.Errorf("BeASymlink matcher expects a path")
    41  	}
    42  
    43  	fi, err := os.Lstat(path)
    44  	if err != nil {
    45  		return false, fmt.Errorf("Unable to stat file: %s", err.Error())
    46  	}
    47  
    48  	if fi.Mode()&os.ModeSymlink != os.ModeSymlink {
    49  		return false, nil
    50  	}
    51  
    52  	target, err := os.Readlink(path)
    53  	if err != nil {
    54  		return false, fmt.Errorf("Unable to read link :%s", err.Error())
    55  	}
    56  
    57  	return target == m.target, nil
    58  }
    59  
    60  func (m *beASymlinkMatcher) FailureMessage(actual interface{}) string {
    61  	return fmt.Sprintf("Expected\n\t%#v\nto be a symlink to\n\t%#v", actual, m.target)
    62  }
    63  
    64  func (m *beASymlinkMatcher) NegatedFailureMessage(actual interface{}) string {
    65  	return fmt.Sprintf("Expected\n\t%#v\nnot to be a symlink to\n\t%#v", actual, m.target)
    66  }