add branch set-base as a way to go back to the integration branch

Author: Byron

crates/gitbutler-cli/src/args.rs

@@ -51,6 +51,11 @@ pub mod vbranch {
         ListLocal,
         /// Provide the current state of all applied virtual branches.
         Status,
+        /// Switch to the GitButler workspace.
+        SetBase {
+            /// The name of the remote branch to integrate with, like `origin/main`.
+            short_tracking_branch_name: String,
+        },
         /// Make the named branch the default so all worktree or index changes are associated with it automatically.
         SetDefault {
             /// The name of the new default virtual branch.

crates/gitbutler-cli/src/command/vbranch.rs

@@ -7,6 +7,16 @@ use gitbutler_stack::{Stack, VirtualBranchesHandle};
 
 use crate::command::debug_print;
 
+pub fn set_base(project: Project, short_tracking_branch_name: String) -> Result<()> {
+    let branch_name = format!("refs/remotes/{}", short_tracking_branch_name)
+        .parse()
+        .context("Invalid branch name")?;
+    debug_print(gitbutler_branch_actions::set_base_branch(
+        &project,
+        &branch_name,
+    )?)
+}
+
 pub fn list_all(project: Project) -> Result<()> {
     let ctx = CommandContext::open(&project)?;
     debug_print(list_branches(&ctx, None, None)?)

crates/gitbutler-cli/src/main.rs

@@ -28,6 +28,9 @@ fn main() -> Result<()> {
         args::Subcommands::Branch(vbranch::Platform { cmd }) => {
             let project = command::prepare::project_from_path(args.current_dir)?;
             match cmd {
+                Some(vbranch::SubCommands::SetBase {
+                    short_tracking_branch_name,
+                }) => command::vbranch::set_base(project, short_tracking_branch_name),
                 Some(vbranch::SubCommands::ListLocal) => command::vbranch::list_local(project),
                 Some(vbranch::SubCommands::Status) => command::vbranch::status(project),
                 Some(vbranch::SubCommands::Unapply { name }) => {