1 files changed, 105 insertions, 0 deletions
diff --git a/gopls/internal/lsp/regtest/options.go b/gopls/internal/lsp/regtest/options.go
new file mode 100644
index 000000000..3820e96b3
--- /dev/null
+++ b/gopls/internal/lsp/regtest/options.go
@@ -0,0 +1,105 @@
+// Copyright 2022 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package regtest
+
+import "golang.org/x/tools/gopls/internal/lsp/fake"
+
+type runConfig struct {
+	editor    fake.EditorConfig
+	sandbox   fake.SandboxConfig
+	modes     Mode
+	skipHooks bool
+}
+
+// A RunOption augments the behavior of the test runner.
+type RunOption interface {
+	set(*runConfig)
+}
+
+type optionSetter func(*runConfig)
+
+func (f optionSetter) set(opts *runConfig) {
+	f(opts)
+}
+
+// ProxyFiles configures a file proxy using the given txtar-encoded string.
+func ProxyFiles(txt string) RunOption {
+	return optionSetter(func(opts *runConfig) {
+		opts.sandbox.ProxyFiles = fake.UnpackTxt(txt)
+	})
+}
+
+// Modes configures the execution modes that the test should run in.
+//
+// By default, modes are configured by the test runner. If this option is set,
+// it overrides the set of default modes and the test runs in exactly these
+// modes.
+func Modes(modes Mode) RunOption {
+	return optionSetter(func(opts *runConfig) {
+		if opts.modes != 0 {
+			panic("modes set more than once")
+		}
+		opts.modes = modes
+	})
+}
+
+// WindowsLineEndings configures the editor to use windows line endings.
+func WindowsLineEndings() RunOption {
+	return optionSetter(func(opts *runConfig) {
+		opts.editor.WindowsLineEndings = true
+	})
+}
+
+// Settings is a RunOption that sets user-provided configuration for the LSP
+// server.
+//
+// As a special case, the env setting must not be provided via Settings: use
+// EnvVars instead.
+type Settings map[string]interface{}
+
+func (s Settings) set(opts *runConfig) {
+	if opts.editor.Settings == nil {
+		opts.editor.Settings = make(map[string]interface{})
+	}
+	for k, v := range s {
+		opts.editor.Settings[k] = v
+	}
+}
+
+// WorkspaceFolders configures the workdir-relative workspace folders to send
+// to the LSP server. By default the editor sends a single workspace folder
+// corresponding to the workdir root. To explicitly configure no workspace
+// folders, use WorkspaceFolders with no arguments.
+func WorkspaceFolders(relFolders ...string) RunOption {
+	if len(relFolders) == 0 {
+		// Use an empty non-nil slice to signal explicitly no folders.
+		relFolders = []string{}
+	}
+	return optionSetter(func(opts *runConfig) {
+		opts.editor.WorkspaceFolders = relFolders
+	})
+}
+
+// EnvVars sets environment variables for the LSP session. When applying these
+// variables to the session, the special string $SANDBOX_WORKDIR is replaced by
+// the absolute path to the sandbox working directory.
+type EnvVars map[string]string
+
+func (e EnvVars) set(opts *runConfig) {
+	if opts.editor.Env == nil {
+		opts.editor.Env = make(map[string]string)
+	}
+	for k, v := range e {
+		opts.editor.Env[k] = v
+	}
+}
+
+// InGOPATH configures the workspace working directory to be GOPATH, rather
+// than a separate working directory for use with modules.
+func InGOPATH() RunOption {
+	return optionSetter(func(opts *runConfig) {
+		opts.sandbox.InGoPath = true
+	})
+}