Initial but absorb implementation

Author: krlvi

crates/but/src/absorb/mod.rs

@@ -0,0 +1,48 @@
+use but_settings::AppSettings;
+use gitbutler_command_context::CommandContext;
+use gitbutler_project::Project;
+
+use crate::{id::CliId, rub::parse_sources};
+
+/// Amends changes into the appropriate commits where they belong.
+///
+/// The semantic for finding "the appropriate commit" is as follows
+/// - Changes are amended into the topmost commit of the leftmost (first) lane (branch)
+/// - If a change is assigned to a particular lane (branch), it will be amended into a commit there
+///     - If there are no commits in this branch, a new commit is created
+/// - If a change has a dependency to a particular commit, it will be amended into that particular commit
+///
+/// Optionally an identifier to an Uncommitted File or a Branch (stack) may be provided.
+///
+/// If an Uncommitted File id is provided, absorb will be peformed for just that file
+/// If a Branch (stack) id is provided, absorb will be performed for all changes assigned to that stack
+/// If no source is provided, absorb is performed for all uncommitted changes
+pub(crate) fn handle(project: &Project, _json: bool, source: Option<&str>) -> anyhow::Result<()> {
+    let ctx = &mut CommandContext::open(project, AppSettings::load_from_default_path_creating()?)?;
+    let source: Option<CliId> = source
+        .and_then(|s| parse_sources(ctx, s).ok())
+        .and_then(|s| {
+            s.into_iter().find(|s| {
+                matches!(s, CliId::UncommittedFile { .. }) || matches!(s, CliId::Branch { .. })
+            })
+        });
+    if let Some(source) = source {
+        match source {
+            CliId::UncommittedFile {
+                path: _,
+                assignment: _,
+            } => {
+                // Absorb this particular file
+            }
+            CliId::Branch { name: _ } => {
+                // Absorb everything that is assigned to this lane
+            }
+            _ => {
+                // Invalid source - error out
+            }
+        }
+    } else {
+        // Try to absorb everhting uncommitted
+    }
+    Ok(())
+}

crates/but/src/args.rs

@@ -186,6 +186,12 @@ For examples see `but rub --help`."
         #[clap(value_enum)]
         shell: Option<clap_complete::Shell>,
     },
+    Absorb {
+        /// If the CliID is an uncommitted change - the change will be absorbed
+        /// If the CliID is a stack - anything assigned to the stack will be absorbed accordingly
+        /// If not provided, everything that is uncommitted will be absorbed
+        source: Option<String>,
+    },
 }
 
 #[derive(Debug, Clone, Copy, clap::ValueEnum, Default)]

crates/but/src/lib.rs

@@ -10,6 +10,7 @@ use colored::Colorize;
 use gix::date::time::CustomFormat;
 use metrics::{Event, Metrics, Props, metrics_if_configured};
 
+mod absorb;
 mod base;
 mod branch;
 mod command;
@@ -327,6 +328,12 @@ async fn match_subcommand(
             metrics_if_configured(app_settings, CommandName::Snapshot, props(start, &result)).ok();
             result
         }
+        Subcommands::Absorb { source } => {
+            let project = get_or_init_project(&args.current_dir)?;
+            let result = absorb::handle(&project, args.json, source.as_deref());
+            metrics_if_configured(app_settings, CommandName::Snapshot, props(start, &result)).ok();
+            result
+        }
         Subcommands::Init { repo } => init::repo(&args.current_dir, args.json, *repo)
             .context("Failed to initialize GitButler project."),
         Subcommands::Forge(forge::integration::Platform { cmd }) => {

crates/but/src/rub/mod.rs

@@ -166,7 +166,7 @@ fn ids(
     Ok((sources, target_result[0].clone()))
 }
 
-fn parse_sources(ctx: &mut CommandContext, source: &str) -> anyhow::Result<Vec<CliId>> {
+pub(crate) fn parse_sources(ctx: &mut CommandContext, source: &str) -> anyhow::Result<Vec<CliId>> {
     // Check if it's a range (contains '-')
     if source.contains('-') {
         parse_range(ctx, source)