cuelang.org/go@v0.10.1/internal/vcs/git.go (about)

     1  // Copyright 2024 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 vcs
    16  
    17  import (
    18  	"context"
    19  	"fmt"
    20  	"path/filepath"
    21  	"sort"
    22  	"strconv"
    23  	"strings"
    24  	"time"
    25  )
    26  
    27  type gitVCS struct {
    28  	root string
    29  }
    30  
    31  func newGitVCS(dir string) (VCS, error) {
    32  	root := findRoot(dir, ".git")
    33  	if root == "" {
    34  		return nil, &vcsNotFoundError{
    35  			kind: "git",
    36  			dir:  dir,
    37  		}
    38  	}
    39  	return gitVCS{
    40  		root: root,
    41  	}, nil
    42  }
    43  
    44  // Root implements [VCS.Root].
    45  func (v gitVCS) Root() string {
    46  	return v.root
    47  }
    48  
    49  // fixDir adjusts dir according to the semantics described in [VCS.ListFiles].
    50  func fixDir(v VCS, dir string) string {
    51  	if dir == "" {
    52  		return v.Root()
    53  	}
    54  	if !filepath.IsAbs(dir) {
    55  		return filepath.Join(v.Root(), dir)
    56  	}
    57  	return dir
    58  }
    59  
    60  // ListFiles implements [VCS.ListFiles].
    61  func (v gitVCS) ListFiles(ctx context.Context, dir string, paths ...string) ([]string, error) {
    62  	dir = fixDir(v, dir)
    63  
    64  	// TODO should we use --recurse-submodules?
    65  	gitargs := append([]string{"ls-files", "-z", "--"}, paths...)
    66  	out, err := runCmd(ctx, dir, "git", gitargs...)
    67  	if err != nil {
    68  		return nil, err
    69  	}
    70  	out = strings.TrimSuffix(out, "\x00")
    71  	if out == "" {
    72  		return nil, nil
    73  	}
    74  	files := strings.Split(out, "\x00")
    75  	sort.Strings(files)
    76  	return files, nil
    77  }
    78  
    79  // Status implements [VCS.Status].
    80  func (v gitVCS) Status(ctx context.Context, paths ...string) (Status, error) {
    81  	gitargs := append([]string{"status", "--porcelain", "--"}, paths...)
    82  	out, err := runCmd(ctx, v.root, "git", gitargs...)
    83  	if err != nil {
    84  		return Status{}, err
    85  	}
    86  	uncommitted := len(out) > 0
    87  
    88  	// "git status" works for empty repositories, but "git log" does not.
    89  	// Assume there are no commits in the repo when "git log" fails with
    90  	// uncommitted files and skip tagging revision / committime.
    91  	var rev string
    92  	var commitTime time.Time
    93  	out, err = runCmd(ctx, v.root, "git",
    94  		"-c", "log.showsignature=false",
    95  		"log", "-1", "--format=%H:%ct",
    96  	)
    97  	if err != nil && !uncommitted {
    98  		return Status{}, err
    99  	}
   100  	if err == nil {
   101  		rev, commitTime, err = parseRevTime(out)
   102  		if err != nil {
   103  			return Status{}, err
   104  		}
   105  	}
   106  	return Status{
   107  		Revision:    rev,
   108  		CommitTime:  commitTime,
   109  		Uncommitted: uncommitted,
   110  	}, nil
   111  }
   112  
   113  // parseRevTime parses commit details in "revision:seconds" format.
   114  func parseRevTime(out string) (string, time.Time, error) {
   115  	buf := strings.TrimSpace(out)
   116  
   117  	rev, t, _ := strings.Cut(buf, ":")
   118  	if rev == "" {
   119  		return "", time.Time{}, fmt.Errorf("unrecognized VCS tool output %q", out)
   120  	}
   121  
   122  	secs, err := strconv.ParseInt(t, 10, 64)
   123  	if err != nil {
   124  		return "", time.Time{}, fmt.Errorf("unrecognized VCS tool output: %v", err)
   125  	}
   126  
   127  	return rev, time.Unix(secs, 0), nil
   128  }