Add buf config ls-modules (#3081)

Fixes #3035.

---------

Co-authored-by: Oliver Sun <73540835+oliversun9@users.noreply.github.com>
Co-authored-by: Oliver Sun <osun@buf.build>

.golangci.yml

@@ -276,3 +276,9 @@ issues:
       # This greatly simplifies creation of descriptors, and it's safe enough since
       # it's just test code.
       path: private/bufpkg/bufimage/source_retention_options_test\.go
+    - linters:
+        - paralleltest
+      path: private/buf/cmd/buf/buf_test.go
+      # The LsModules tests call chdir and cannot be parallelized.
+      text: "LsModules"
+

CHANGELOG.md

@@ -2,6 +2,7 @@
 
 ## [Unreleased]
 
+- Add `buf config ls-modules` command to list configured modules.
 - Fix issue where `buf generate` would succeed on missing insertion points and 
   panic on empty insertion point files.
 - Update `buf generate` to allow the use of Editions syntax when doing local code

private/buf/bufcli/buf_work_yaml_file.go

@@ -0,0 +1,33 @@
+// Copyright 2020-2024 Buf Technologies, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package bufcli
+
+import (
+	"context"
+
+	"github.com/bufbuild/buf/private/bufpkg/bufconfig"
+)
+
+// GetBufWorkYAMLFileForDirPath gets the buf.work.yaml file for the directory path.
+func GetBufWorkYAMLFileForDirPath(
+	ctx context.Context,
+	dirPath string,
+) (bufconfig.BufWorkYAMLFile, error) {
+	bucket, err := newOSReadWriteBucketWithSymlinks(dirPath)
+	if err != nil {
+		return nil, err
+	}
+	return bufconfig.GetBufWorkYAMLFileForPrefix(ctx, bucket, ".")
+}

private/buf/cmd/buf/buf.go

@@ -60,6 +60,7 @@ import (
 	"github.com/bufbuild/buf/private/buf/cmd/buf/command/config/configinit"
 	"github.com/bufbuild/buf/private/buf/cmd/buf/command/config/configlsbreakingrules"
 	"github.com/bufbuild/buf/private/buf/cmd/buf/command/config/configlslintrules"
+	"github.com/bufbuild/buf/private/buf/cmd/buf/command/config/configlsmodules"
 	"github.com/bufbuild/buf/private/buf/cmd/buf/command/config/configmigrate"
 	"github.com/bufbuild/buf/private/buf/cmd/buf/command/convert"
 	"github.com/bufbuild/buf/private/buf/cmd/buf/command/curl"
@@ -137,6 +138,7 @@ func NewRootCommand(name string) *appcmd.Command {
 					configmigrate.NewCommand("migrate", builder),
 					configlslintrules.NewCommand("ls-lint-rules", builder),
 					configlsbreakingrules.NewCommand("ls-breaking-rules", builder),
+					configlsmodules.NewCommand("ls-modules", builder),
 				},
 			},
 			{