Support multi-dir wildcards in .dockerignore

Closes #13113

Signed-off-by: Doug Davis <dug@us.ibm.com>

fileutils/fileutils.go

@@ -6,7 +6,9 @@ import (
 	"io"
 	"os"
 	"path/filepath"
+	"regexp"
 	"strings"
+	"text/scanner"
 
 	"github.com/Sirupsen/logrus"
 )
@@ -92,15 +94,15 @@ func OptimizedMatches(file string, patterns []string, patDirs [][]string) (bool,
 			pattern = pattern[1:]
 		}
 
-		match, err := filepath.Match(pattern, file)
+		match, err := regexpMatch(pattern, file)
 		if err != nil {
-			return false, err
+			return false, fmt.Errorf("Error in pattern (%s): %s", pattern, err)
 		}
 
 		if !match && parentPath != "." {
 			// Check to see if the pattern matches one of our parent dirs.
 			if len(patDirs[i]) <= len(parentPathDirs) {
-				match, _ = filepath.Match(strings.Join(patDirs[i], "/"),
+				match, _ = regexpMatch(strings.Join(patDirs[i], "/"),
 					strings.Join(parentPathDirs[:len(patDirs[i])], "/"))
 			}
 		}
@@ -117,6 +119,99 @@ func OptimizedMatches(file string, patterns []string, patDirs [][]string) (bool,
 	return matched, nil
 }
 
+// regexpMatch tries to match the logic of filepath.Match but
+// does so using regexp logic. We do this so that we can expand the
+// wildcard set to include other things, like "**" to mean any number
+// of directories.  This means that we should be backwards compatible
+// with filepath.Match(). We'll end up supporting more stuff, due to
+// the fact that we're using regexp, but that's ok - it does no harm.
+func regexpMatch(pattern, path string) (bool, error) {
+	regStr := "^"
+
+	// Do some syntax checking on the pattern.
+	// filepath's Match() has some really weird rules that are inconsistent
+	// so instead of trying to dup their logic, just call Match() for its
+	// error state and if there is an error in the pattern return it.
+	// If this becomes an issue we can remove this since its really only
+	// needed in the error (syntax) case - which isn't really critical.
+	if _, err := filepath.Match(pattern, path); err != nil {
+		return false, err
+	}
+
+	// Go through the pattern and convert it to a regexp.
+	// We use a scanner so we can support utf-8 chars.
+	var scan scanner.Scanner
+	scan.Init(strings.NewReader(pattern))
+
+	sl := string(os.PathSeparator)
+	escSL := sl
+	if sl == `\` {
+		escSL += `\`
+	}
+
+	for scan.Peek() != scanner.EOF {
+		ch := scan.Next()
+
+		if ch == '*' {
+			if scan.Peek() == '*' {
+				// is some flavor of "**"
+				scan.Next()
+
+				if scan.Peek() == scanner.EOF {
+					// is "**EOF" - to align with .gitignore just accept all
+					regStr += ".*"
+				} else {
+					// is "**"
+					regStr += "((.*" + escSL + ")|([^" + escSL + "]*))"
+				}
+
+				// Treat **/ as ** so eat the "/"
+				if string(scan.Peek()) == sl {
+					scan.Next()
+				}
+			} else {
+				// is "*" so map it to anything but "/"
+				regStr += "[^" + escSL + "]*"
+			}
+		} else if ch == '?' {
+			// "?" is any char except "/"
+			regStr += "[^" + escSL + "]"
+		} else if strings.Index(".$", string(ch)) != -1 {
+			// Escape some regexp special chars that have no meaning
+			// in golang's filepath.Match
+			regStr += `\` + string(ch)
+		} else if ch == '\\' {
+			// escape next char. Note that a trailing \ in the pattern
+			// will be left alone (but need to escape it)
+			if sl == `\` {
+				// On windows map "\" to "\\", meaning an escaped backslash,
+				// and then just continue because filepath.Match on
+				// Windows doesn't allow escaping at all
+				regStr += escSL
+				continue
+			}
+			if scan.Peek() != scanner.EOF {
+				regStr += `\` + string(scan.Next())
+			} else {
+				regStr += `\`
+			}
+		} else {
+			regStr += string(ch)
+		}
+	}
+
+	regStr += "$"
+
+	res, err := regexp.MatchString(regStr, path)
+
+	// Map regexp's error to filepath's so no one knows we're not using filepath
+	if err != nil {
+		err = filepath.ErrBadPattern
+	}
+
+	return res, err
+}
+
 // CopyFile copies from src to dst until either EOF is reached
 // on src or an error occurs. It verifies src exists and remove
 // the dst if it exists.

fileutils/fileutils_test.go

@@ -5,6 +5,8 @@ import (
 	"os"
 	"path"
 	"path/filepath"
+	"runtime"
+	"strings"
 	"testing"
 )
 
@@ -297,6 +299,84 @@ func TestMatchesWithMalformedPatterns(t *testing.T) {
 	}
 }
 
+// Test lots of variants of patterns & strings
+func TestMatches(t *testing.T) {
+	tests := []struct {
+		pattern string
+		text    string
+		pass    bool
+	}{
+		{"**", "file", true},
+		{"**", "file/", true},
+		{"**/", "file", true}, // weird one
+		{"**/", "file/", true},
+		{"**", "/", true},
+		{"**/", "/", true},
+		{"**", "dir/file", true},
+		{"**/", "dir/file", false},
+		{"**", "dir/file/", true},
+		{"**/", "dir/file/", true},
+		{"**/**", "dir/file", true},
+		{"**/**", "dir/file/", true},
+		{"dir/**", "dir/file", true},
+		{"dir/**", "dir/file/", true},
+		{"dir/**", "dir/dir2/file", true},
+		{"dir/**", "dir/dir2/file/", true},
+		{"**/dir2/*", "dir/dir2/file", true},
+		{"**/dir2/*", "dir/dir2/file/", false},
+		{"**/dir2/**", "dir/dir2/dir3/file", true},
+		{"**/dir2/**", "dir/dir2/dir3/file/", true},
+		{"**file", "file", true},
+		{"**file", "dir/file", true},
+		{"**/file", "dir/file", true},
+		{"**file", "dir/dir/file", true},
+		{"**/file", "dir/dir/file", true},
+		{"**/file*", "dir/dir/file", true},
+		{"**/file*", "dir/dir/file.txt", true},
+		{"**/file*txt", "dir/dir/file.txt", true},
+		{"**/file*.txt", "dir/dir/file.txt", true},
+		{"**/file*.txt*", "dir/dir/file.txt", true},
+		{"**/**/*.txt", "dir/dir/file.txt", true},
+		{"**/**/*.txt2", "dir/dir/file.txt", false},
+		{"**/*.txt", "file.txt", true},
+		{"**/**/*.txt", "file.txt", true},
+		{"a**/*.txt", "a/file.txt", true},
+		{"a**/*.txt", "a/dir/file.txt", true},
+		{"a**/*.txt", "a/dir/dir/file.txt", true},
+		{"a/*.txt", "a/dir/file.txt", false},
+		{"a/*.txt", "a/file.txt", true},
+		{"a/*.txt**", "a/file.txt", true},
+		{"a[b-d]e", "ae", false},
+		{"a[b-d]e", "ace", true},
+		{"a[b-d]e", "aae", false},
+		{"a[^b-d]e", "aze", true},
+		{".*", ".foo", true},
+		{".*", "foo", false},
+		{"abc.def", "abcdef", false},
+		{"abc.def", "abc.def", true},
+		{"abc.def", "abcZdef", false},
+		{"abc?def", "abcZdef", true},
+		{"abc?def", "abcdef", false},
+		{"a\\*b", "a*b", true},
+		{"a\\", "a", false},
+		{"a\\", "a\\", false},
+		{"a\\\\", "a\\", true},
+		{"**/foo/bar", "foo/bar", true},
+		{"**/foo/bar", "dir/foo/bar", true},
+		{"**/foo/bar", "dir/dir2/foo/bar", true},
+		{"abc/**", "abc", false},
+		{"abc/**", "abc/def", true},
+		{"abc/**", "abc/def/ghi", true},
+	}
+
+	for _, test := range tests {
+		res, _ := regexpMatch(test.pattern, test.text)
+		if res != test.pass {
+			t.Fatalf("Failed: %v - res:%v", test, res)
+		}
+	}
+}
+
 // An empty string should return true from Empty.
 func TestEmpty(t *testing.T) {
 	empty := empty("")
@@ -400,3 +480,94 @@ func TestCreateIfNotExistsFile(t *testing.T) {
 		t.Fatalf("Should have been a file, seems it's not")
 	}
 }
+
+// These matchTests are stolen from go's filepath Match tests.
+type matchTest struct {
+	pattern, s string
+	match      bool
+	err        error
+}
+
+var matchTests = []matchTest{
+	{"abc", "abc", true, nil},
+	{"*", "abc", true, nil},
+	{"*c", "abc", true, nil},
+	{"a*", "a", true, nil},
+	{"a*", "abc", true, nil},
+	{"a*", "ab/c", false, nil},
+	{"a*/b", "abc/b", true, nil},
+	{"a*/b", "a/c/b", false, nil},
+	{"a*b*c*d*e*/f", "axbxcxdxe/f", true, nil},
+	{"a*b*c*d*e*/f", "axbxcxdxexxx/f", true, nil},
+	{"a*b*c*d*e*/f", "axbxcxdxe/xxx/f", false, nil},
+	{"a*b*c*d*e*/f", "axbxcxdxexxx/fff", false, nil},
+	{"a*b?c*x", "abxbbxdbxebxczzx", true, nil},
+	{"a*b?c*x", "abxbbxdbxebxczzy", false, nil},
+	{"ab[c]", "abc", true, nil},
+	{"ab[b-d]", "abc", true, nil},
+	{"ab[e-g]", "abc", false, nil},
+	{"ab[^c]", "abc", false, nil},
+	{"ab[^b-d]", "abc", false, nil},
+	{"ab[^e-g]", "abc", true, nil},
+	{"a\\*b", "a*b", true, nil},
+	{"a\\*b", "ab", false, nil},
+	{"a?b", "a☺b", true, nil},
+	{"a[^a]b", "a☺b", true, nil},
+	{"a???b", "a☺b", false, nil},
+	{"a[^a][^a][^a]b", "a☺b", false, nil},
+	{"[a-ζ]*", "α", true, nil},
+	{"*[a-ζ]", "A", false, nil},
+	{"a?b", "a/b", false, nil},
+	{"a*b", "a/b", false, nil},
+	{"[\\]a]", "]", true, nil},
+	{"[\\-]", "-", true, nil},
+	{"[x\\-]", "x", true, nil},
+	{"[x\\-]", "-", true, nil},
+	{"[x\\-]", "z", false, nil},
+	{"[\\-x]", "x", true, nil},
+	{"[\\-x]", "-", true, nil},
+	{"[\\-x]", "a", false, nil},
+	{"[]a]", "]", false, filepath.ErrBadPattern},
+	{"[-]", "-", false, filepath.ErrBadPattern},
+	{"[x-]", "x", false, filepath.ErrBadPattern},
+	{"[x-]", "-", false, filepath.ErrBadPattern},
+	{"[x-]", "z", false, filepath.ErrBadPattern},
+	{"[-x]", "x", false, filepath.ErrBadPattern},
+	{"[-x]", "-", false, filepath.ErrBadPattern},
+	{"[-x]", "a", false, filepath.ErrBadPattern},
+	{"\\", "a", false, filepath.ErrBadPattern},
+	{"[a-b-c]", "a", false, filepath.ErrBadPattern},
+	{"[", "a", false, filepath.ErrBadPattern},
+	{"[^", "a", false, filepath.ErrBadPattern},
+	{"[^bc", "a", false, filepath.ErrBadPattern},
+	{"a[", "a", false, filepath.ErrBadPattern}, // was nil but IMO its wrong
+	{"a[", "ab", false, filepath.ErrBadPattern},
+	{"*x", "xxx", true, nil},
+}
+
+func errp(e error) string {
+	if e == nil {
+		return "<nil>"
+	}
+	return e.Error()
+}
+
+// TestMatch test's our version of filepath.Match, called regexpMatch.
+func TestMatch(t *testing.T) {
+	for _, tt := range matchTests {
+		pattern := tt.pattern
+		s := tt.s
+		if runtime.GOOS == "windows" {
+			if strings.Index(pattern, "\\") >= 0 {
+				// no escape allowed on windows.
+				continue
+			}
+			pattern = filepath.Clean(pattern)
+			s = filepath.Clean(s)
+		}
+		ok, err := regexpMatch(pattern, s)
+		if ok != tt.match || err != tt.err {
+			t.Fatalf("Match(%#q, %#q) = %v, %q want %v, %q", pattern, s, ok, errp(err), tt.match, errp(tt.err))
+		}
+	}
+}