github.com/joomcode/cue@v0.4.4-0.20221111115225-539fe3512047/cue/load/match.go (about)

     1  // Copyright 2018 The CUE Authors
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package load
    16  
    17  import (
    18  	"io/ioutil"
    19  	"path/filepath"
    20  	"strings"
    21  
    22  	"github.com/joomcode/cue/cue/build"
    23  	"github.com/joomcode/cue/cue/errors"
    24  	"github.com/joomcode/cue/cue/token"
    25  )
    26  
    27  var errExclude = errors.New("file rejected")
    28  
    29  type cueError = errors.Error
    30  type excludeError struct {
    31  	cueError
    32  }
    33  
    34  func (e excludeError) Is(err error) bool { return err == errExclude }
    35  
    36  // matchFile determines whether the file with the given name in the given directory
    37  // should be included in the package being constructed.
    38  // It returns the data read from the file.
    39  // If returnImports is true and name denotes a CUE file, matchFile reads
    40  // until the end of the imports (and returns that data) even though it only
    41  // considers text until the first non-comment.
    42  // If allTags is non-nil, matchFile records any encountered build tag
    43  // by setting allTags[tag] = true.
    44  func matchFile(cfg *Config, file *build.File, returnImports, allFiles bool, allTags map[string]bool) (match bool, data []byte, err errors.Error) {
    45  	if fi := cfg.fileSystem.getOverlay(file.Filename); fi != nil {
    46  		if fi.file != nil {
    47  			file.Source = fi.file
    48  		} else {
    49  			file.Source = fi.contents
    50  		}
    51  	}
    52  
    53  	if file.Encoding != build.CUE {
    54  		return false, nil, nil // not a CUE file, don't record.
    55  	}
    56  
    57  	if file.Filename == "-" {
    58  		b, err2 := ioutil.ReadAll(cfg.stdin())
    59  		if err2 != nil {
    60  			err = errors.Newf(token.NoPos, "read stdin: %v", err)
    61  			return
    62  		}
    63  		file.Source = b
    64  		return true, b, nil // don't check shouldBuild for stdin
    65  	}
    66  
    67  	name := filepath.Base(file.Filename)
    68  	if !cfg.filesMode && strings.HasPrefix(name, ".") {
    69  		return false, nil, &excludeError{
    70  			errors.Newf(token.NoPos, "filename starts with a '.'"),
    71  		}
    72  	}
    73  
    74  	if strings.HasPrefix(name, "_") {
    75  		return false, nil, &excludeError{
    76  			errors.Newf(token.NoPos, "filename starts with a '_"),
    77  		}
    78  	}
    79  
    80  	f, err := cfg.fileSystem.openFile(file.Filename)
    81  	if err != nil {
    82  		return false, nil, err
    83  	}
    84  
    85  	data, err = readImports(f, false, nil)
    86  	f.Close()
    87  	if err != nil {
    88  		return false, nil,
    89  			errors.Newf(token.NoPos, "read %s: %v", file.Filename, err)
    90  	}
    91  
    92  	return true, data, nil
    93  }