Implement pulumi stack unselect

CHANGELOG_PENDING.md

@@ -1,5 +1,6 @@
 ### Improvements
 
+- [area/cli] - Implement `pulumi stack unselect` [#9179](https://github.com/pulumi/pulumi/pull/9179)
 - [language/dotnet] - Updated Pulumi dotnet packages to use grpc-dotnet instead of grpc.
    [#9149](https://github.com/pulumi/pulumi/pull/9149)
 

pkg/cmd/pulumi/stack.go

@@ -185,6 +185,7 @@ func newStackCmd() *cobra.Command {
 	cmd.AddCommand(newStackRenameCmd())
 	cmd.AddCommand(newStackChangeSecretsProviderCmd())
 	cmd.AddCommand(newStackHistoryCmd())
+	cmd.AddCommand(newStackUnselectCmd())
 
 	return cmd
 }

pkg/cmd/pulumi/stack_unselect.go

@@ -0,0 +1,61 @@
+// Copyright 2016-2022, Pulumi Corporation.
+//
+// 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 main
+
+import (
+	"fmt"
+
+	"github.com/pulumi/pulumi/sdk/v3/go/common/util/cmdutil"
+	"github.com/pulumi/pulumi/sdk/v3/go/common/workspace"
+	"github.com/spf13/cobra"
+)
+
+// Resets the currently selected stack from the current workspace such that
+// next time the users get prompted with a stack to select
+func newStackUnselectCmd() *cobra.Command {
+	return &cobra.Command{
+		Use:   "unselect",
+		Short: "Resets stack selection from the current workspace",
+		Long: "Resets stack selection from the current workspace.\n" +
+			"\n" +
+			"This way, next time pulumi needs to execute an operation, the user is prompted with one of the stacks to select\n" +
+			"from.\n",
+		Args: cmdutil.NoArgs,
+		Run: cmdutil.RunFunc(func(cmd *cobra.Command, args []string) error {
+			currentWorkspace, err := workspace.New()
+			if err != nil {
+				return err
+			}
+
+			settings := currentWorkspace.Settings()
+			if !settings.IsEmpty() {
+				// a stack is selected
+				// reset it
+				settings.Stack = ""
+				saveResult := currentWorkspace.Save()
+				if saveResult == nil {
+					// saving changes was successful
+					fmt.Println("Stack was unselected")
+				} else {
+					fmt.Println("Something went wrong when unselecting the current stack from the workspace")
+				}
+
+				return saveResult
+			}
+
+			return nil
+		}),
+	}
+}

tests/stack_test.go

@@ -113,6 +113,35 @@ func TestStackCommands(t *testing.T) {
 		e.RunCommand("pulumi", "stack", "rm", "--yes")
 	})
 
+	t.Run("StackUnselect", func(t *testing.T) {
+		t.Parallel()
+
+		e := ptesting.NewEnvironment(t)
+		defer func() {
+			if !t.Failed() {
+				e.DeleteEnvironment()
+			}
+		}()
+
+		integration.CreateBasicPulumiRepo(e)
+		e.SetBackend(e.LocalURL())
+		e.RunCommand("pulumi", "stack", "init", "one")
+		e.RunCommand("pulumi", "stack", "init", "two")
+
+		// Last one created is always selected.
+		stacks, current := integration.GetStacks(e)
+		if current == nil {
+			t.Fatalf("No stack was labeled as current among: %v", stacks)
+		}
+		assert.Equal(t, "two", *current)
+
+		e.RunCommand("pulumi", "stack", "unselect")
+		_, updatedCurrentStack := integration.GetStacks(e)
+		if updatedCurrentStack != nil {
+			t.Fatal("No stack should be selected after unselect was executed")
+		}
+	})
+
 	t.Run("StackRm", func(t *testing.T) {
 		t.Parallel()