Add git.GetTrackedFiles for reporting list of files tracked in git

git/git.go

@@ -753,3 +753,30 @@ func RemoteRefs(remoteName string) ([]*Ref, error) {
 	}
 	return ret, nil
 }
+
+// GetTrackedFiles returns a list of files which are tracked in Git which match
+// the pattern specified (standard wildcard form)
+// Both pattern and the results are relative to the current working directory, not
+// the root of the repository
+func GetTrackedFiles(pattern string) ([]string, error) {
+	var ret []string
+	cmd := subprocess.ExecCommand("git",
+		"-c", "core.quotepath=false", // handle special chars in filenames
+		"ls-files",
+		"--cached", // include things which are staged but not committed right now
+		"--",       // no ambiguous patterns
+		pattern)
+
+	outp, err := cmd.StdoutPipe()
+	if err != nil {
+		return nil, fmt.Errorf("Failed to call git ls-files: %v", err)
+	}
+	cmd.Start()
+	scanner := bufio.NewScanner(outp)
+	for scanner.Scan() {
+		line := scanner.Text()
+		ret = append(ret, strings.TrimSpace(line))
+	}
+	return ret, nil
+
+}

git/git_test.go

@@ -1,6 +1,8 @@
 package git_test // to avoid import cycles
 
 import (
+	"io/ioutil"
+	"os"
 	"path/filepath"
 	"sort"
 	"testing"
@@ -280,3 +282,99 @@ func TestGitAndRootDirs(t *testing.T) {
 
 	assert.Equal(t, git, filepath.Join(root, ".git"))
 }
+
+func TestGetTrackedFiles(t *testing.T) {
+	repo := test.NewRepo(t)
+	repo.Pushd()
+	defer func() {
+		repo.Popd()
+		repo.Cleanup()
+	}()
+
+	// test commits; we'll just modify the same file each time since we're
+	// only interested in branches
+	inputs := []*test.CommitInput{
+		{ // 0
+			Files: []*test.FileInput{
+				{Filename: "file1.txt", Size: 20},
+				{Filename: "file2.txt", Size: 20},
+				{Filename: "folder1/file10.txt", Size: 20},
+				{Filename: "folder1/anotherfile.txt", Size: 20},
+			},
+		},
+		{ // 1
+			Files: []*test.FileInput{
+				{Filename: "file3.txt", Size: 20},
+				{Filename: "file4.txt", Size: 20},
+				{Filename: "folder2/something.txt", Size: 20},
+				{Filename: "folder2/folder3/deep.txt", Size: 20},
+			},
+		},
+	}
+	repo.AddCommits(inputs)
+
+	tracked, err := GetTrackedFiles("*.txt")
+	assert.Equal(t, nil, err)
+	sort.Strings(tracked) // for direct comparison
+	fulllist := []string{"file1.txt", "file2.txt", "file3.txt", "file4.txt", "folder1/anotherfile.txt", "folder1/file10.txt", "folder2/folder3/deep.txt", "folder2/something.txt"}
+	assert.Equal(t, fulllist, tracked)
+
+	tracked, err = GetTrackedFiles("*file*.txt")
+	assert.Equal(t, nil, err)
+	sort.Strings(tracked)
+	sublist := []string{"file1.txt", "file2.txt", "file3.txt", "file4.txt", "folder1/anotherfile.txt", "folder1/file10.txt"}
+	assert.Equal(t, sublist, tracked)
+
+	tracked, err = GetTrackedFiles("folder1/*")
+	assert.Equal(t, nil, err)
+	sort.Strings(tracked)
+	sublist = []string{"folder1/anotherfile.txt", "folder1/file10.txt"}
+	assert.Equal(t, sublist, tracked)
+
+	tracked, err = GetTrackedFiles("folder2/*")
+	assert.Equal(t, nil, err)
+	sort.Strings(tracked)
+	sublist = []string{"folder2/folder3/deep.txt", "folder2/something.txt"}
+	assert.Equal(t, sublist, tracked)
+
+	// relative dir
+	os.Chdir("folder1")
+	tracked, err = GetTrackedFiles("*.txt")
+	assert.Equal(t, nil, err)
+	sort.Strings(tracked)
+	sublist = []string{"anotherfile.txt", "file10.txt"}
+	assert.Equal(t, sublist, tracked)
+	os.Chdir("..")
+
+	// Test includes staged but uncommitted files
+	ioutil.WriteFile("z_newfile.txt", []byte("Hello world"), 0644)
+	test.RunGitCommand(t, true, "add", "z_newfile.txt")
+	tracked, err = GetTrackedFiles("*.txt")
+	assert.Equal(t, nil, err)
+	sort.Strings(tracked)
+	fulllist = append(fulllist, "z_newfile.txt")
+	assert.Equal(t, fulllist, tracked)
+
+	// Test includes modified files (not staged)
+	ioutil.WriteFile("file1.txt", []byte("Modifications"), 0644)
+	tracked, err = GetTrackedFiles("*.txt")
+	assert.Equal(t, nil, err)
+	sort.Strings(tracked)
+	assert.Equal(t, fulllist, tracked)
+
+	// Test includes modified files (staged)
+	test.RunGitCommand(t, true, "add", "file1.txt")
+	tracked, err = GetTrackedFiles("*.txt")
+	assert.Equal(t, nil, err)
+	sort.Strings(tracked)
+	assert.Equal(t, fulllist, tracked)
+
+	// Test excludes deleted files (not committed)
+	test.RunGitCommand(t, true, "rm", "file2.txt")
+	tracked, err = GetTrackedFiles("*.txt")
+	assert.Equal(t, nil, err)
+	sort.Strings(tracked)
+	deletedlist := []string{"file1.txt", "file3.txt", "file4.txt", "folder1/anotherfile.txt", "folder1/file10.txt", "folder2/folder3/deep.txt", "folder2/something.txt", "z_newfile.txt"}
+	assert.Equal(t, deletedlist, tracked)
+
+}