refactor(fakestorage): use doublestar for MatchGlob matching

Replace the custom globToRegex translator with
doublestar.MatchUnvalidated, per review feedback on #1985.

- doublestar treats a mid-segment ** (img/**.jpg) as a single *, so
  rewrite the two test patterns that relied on it to the segment form
  (img/**/*.jpg); the expected results do not change
- fix a test name that embedded \a as a bell character

Author: zachvictor

fakestorage/object.go

@@ -14,14 +14,14 @@ import (
 	"fmt"
 	"io"
 	"net/http"
-	"regexp"
 	"slices"
 	"sort"
 	"strconv"
 	"strings"
 	"time"
 
 	"cloud.google.com/go/storage"
+	"github.com/bmatcuk/doublestar/v4"
 	"github.com/fsouza/fake-gcs-server/internal/backend"
 	"github.com/fsouza/fake-gcs-server/internal/notification"
 	"github.com/fsouza/fake-gcs-server/internal/urlhelper"
@@ -405,7 +405,7 @@ func (s *Server) ListObjectsWithOptionsPaginated(bucketName string, options List
 			continue
 		}
 
-		if options.MatchGlob != "" && !matchGlob(options.MatchGlob, obj.Name) {
+		if options.MatchGlob != "" && !doublestar.MatchUnvalidated(options.MatchGlob, obj.Name) {
 			continue
 		}
 
@@ -1462,120 +1462,3 @@ func (s *Server) composeObject(r *http.Request) jsonResponse {
 
 	return jsonResponse{data: newObjectResponse(obj.ObjectAttrs, urlhelper.GetBaseURL(r))}
 }
-
-// matchGlob matches a glob pattern against a string following GCS glob syntax.
-// See https://cloud.google.com/storage/docs/json_api/v1/objects/list#list-object-glob
-// Supports:
-// - * matches zero or more characters (excluding /)
-// - ** matches zero or more characters (including /)
-// - ? matches any single character (excluding /)
-// - [abc] matches exactly one character in the set
-// - [a-z] matches one character in a range
-// - [!abc] or [^abc] matches one character NOT in the set
-// - {abc,xyz} matches one of the specified options
-// Doesn't currently support:
-// - nested {} braces
-// - patterns inside {} braces e.g. {*foo,bar*}
-func matchGlob(pattern, name string) bool {
-	regex := globToRegex(pattern)
-	matched, err := regexp.MatchString(regex, name)
-	if err != nil {
-		return false
-	}
-	return matched
-}
-
-func globToRegex(pattern string) string {
-	var result strings.Builder
-	result.WriteString("^")
-
-	i := 0
-	for i < len(pattern) {
-		switch pattern[i] {
-		case '*':
-			if i+1 < len(pattern) && pattern[i+1] == '*' {
-				// ** matches zero or more characters including /
-				result.WriteString(".*")
-				i += 2
-			} else {
-				// * matches zero or more characters excluding /
-				result.WriteString("[^/]*")
-				i++
-			}
-		case '?':
-			// ? matches any single character excluding /
-			result.WriteString("[^/]")
-			i++
-		case '[':
-			// Character class [abc] or [a-z] or [!abc] or [^abc]
-			j := i + 1
-			if j < len(pattern) && (pattern[j] == '!' || pattern[j] == '^') {
-				j++
-			}
-			for j < len(pattern) && pattern[j] != ']' {
-				j++
-			}
-			if j < len(pattern) {
-				// Valid character class
-				charClass := pattern[i : j+1]
-				// Convert [!...] to [^...] for regex
-				if strings.HasPrefix(charClass, "[!") {
-					charClass = "[^" + charClass[2:]
-				}
-				result.WriteString(charClass)
-				i = j + 1
-			} else {
-				// Invalid character class, treat as literal
-				result.WriteString(regexp.QuoteMeta(string(pattern[i])))
-				i++
-			}
-		case '{':
-			// Brace expansion {abc,xyz}
-			j := i + 1
-			depth := 1
-			for j < len(pattern) && depth > 0 {
-				switch pattern[j] {
-				case '{':
-					depth++
-				case '}':
-					depth--
-				}
-				j++
-			}
-			if depth == 0 {
-				// Valid brace expansion
-				braceContent := pattern[i+1 : j-1]
-				options := strings.Split(braceContent, ",")
-				result.WriteString("(")
-				for k, option := range options {
-					if k > 0 {
-						result.WriteString("|")
-					}
-					result.WriteString(regexp.QuoteMeta(option))
-				}
-				result.WriteString(")")
-				i = j
-			} else {
-				// Invalid brace expansion, treat as literal
-				result.WriteString(regexp.QuoteMeta(string(pattern[i])))
-				i++
-			}
-		case '\\':
-			// Escape character
-			if i+1 < len(pattern) {
-				result.WriteString(regexp.QuoteMeta(string(pattern[i+1])))
-				i += 2
-			} else {
-				result.WriteString(regexp.QuoteMeta(string(pattern[i])))
-				i++
-			}
-		default:
-			// Regular character, escape for regex
-			result.WriteString(regexp.QuoteMeta(string(pattern[i])))
-			i++
-		}
-	}
-
-	result.WriteString("$")
-	return result.String()
-}

fakestorage/object_test.go

@@ -1006,7 +1006,7 @@ func getTestCasesForListTests(versioningEnabled, withOverwrites bool) []listTest
 		{
 			fmt.Sprintf("filtering MatchGlob **, versioning %t and overwrites %t", versioningEnabled, withOverwrites),
 			"some-bucket",
-			&storage.Query{MatchGlob: "img/**.jpg"},
+			&storage.Query{MatchGlob: "img/**/*.jpg"},
 			[]string{
 				"img/brand.jpg",
 				"img/hi-res/party-01.jpg",
@@ -1069,7 +1069,7 @@ func getTestCasesForListTests(versioningEnabled, withOverwrites bool) []listTest
 		{
 			fmt.Sprintf("filtering MatchGlob ** and {abc,xyz}, versioning %t and overwrites %t", versioningEnabled, withOverwrites),
 			"some-bucket",
-			&storage.Query{MatchGlob: "img/**{brand,party-01,party-02}.jpg"},
+			&storage.Query{MatchGlob: "img/**/{brand,party-01,party-02}.jpg"},
 			[]string{
 				"img/brand.jpg",
 				"img/hi-res/party-01.jpg",
@@ -1092,7 +1092,7 @@ func getTestCasesForListTests(versioningEnabled, withOverwrites bool) []listTest
 			nil,
 		},
 		{
-			fmt.Sprintf("filtering MatchGlob ** and \a, versioning %t and overwrites %t", versioningEnabled, withOverwrites),
+			fmt.Sprintf(`filtering MatchGlob ** and \a, versioning %t and overwrites %t`, versioningEnabled, withOverwrites),
 			"some-bucket",
 			&storage.Query{MatchGlob: "img/**/party\\-*.jpg"},
 			[]string{

go.mod

@@ -2,6 +2,7 @@ module github.com/fsouza/fake-gcs-server
 
 require (
 	cloud.google.com/go/storage v1.64.0
+	github.com/bmatcuk/doublestar/v4 v4.10.0
 	github.com/fsouza/slognil v0.4.3
 	github.com/google/go-cmp v0.7.0
 	github.com/gorilla/handlers v1.5.2

go.sum

@@ -32,6 +32,8 @@ github.com/GoogleCloudPlatform/opentelemetry-operations-go/internal/cloudmock v0
 github.com/GoogleCloudPlatform/opentelemetry-operations-go/internal/cloudmock v0.57.0/go.mod h1:dzcEjy1WJ0Q4u9twNR3LcLhNoYMRCrMCMafpxa0TjPQ=
 github.com/GoogleCloudPlatform/opentelemetry-operations-go/internal/resourcemapping v0.57.0 h1:RoO5+d7uCmDqovLrHCr2/BuViUXvdcrNxyNM1pN9dDQ=
 github.com/GoogleCloudPlatform/opentelemetry-operations-go/internal/resourcemapping v0.57.0/go.mod h1:YqwkQPrWSC7+byyc1VlKbWLBF5JsW5IoL6xUkemYSXk=
+github.com/bmatcuk/doublestar/v4 v4.10.0 h1:zU9WiOla1YA122oLM6i4EXvGW62DvKZVxIe6TYWexEs=
+github.com/bmatcuk/doublestar/v4 v4.10.0/go.mod h1:xBQ8jztBU6kakFMg+8WGxn0c6z1fTSPVIjEY1Wr7jzc=
 github.com/census-instrumentation/opencensus-proto v0.2.1/go.mod h1:f6KPmirojxKA12rnyqOA5BBL4O983OfeGPqjHWSTneU=
 github.com/cespare/xxhash/v2 v2.3.0 h1:UL815xU9SqsFlibzuggzjXhog7bL6oX9BbNZnL2UFvs=
 github.com/cespare/xxhash/v2 v2.3.0/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=