Add a git switch-and-pull command (#109)

Add a switch and pull command

Cargo.toml

@@ -28,6 +28,7 @@ atomic-counter = "1.0.1"
 ureq = { version = "1.4.0", features = ["json", "native-tls"], default_features = false }
 serde_json = "1.0.57"
 globset = "0.4.5"
+git2 = "0.13.11"
 
 [target."cfg(unix)".dependencies]
 expanduser = "1.2.1"

README.md

@@ -61,25 +61,26 @@ USAGE:
     git-workspace --workspace <workspace> <SUBCOMMAND>
 
 FLAGS:
-    -h, --help
+    -h, --help       
             Prints help information
 
-    -V, --version
+    -V, --version    
             Prints version information
 
 
 OPTIONS:
-    -w, --workspace <workspace>
-             [env: GIT_WORKSPACE=...]
+    -w, --workspace <workspace>    
+             [env: GIT_WORKSPACE=/Users/tom/PycharmProjects/]
 
 
 SUBCOMMANDS:
-    add       Add a provider to the configuration
-    fetch     Fetch new commits for all repositories in the workspace
-    help      Prints this message or the help of the given subcommand(s)
-    list      List all repositories in the workspace
-    run       Run a git command in all repositories
-    update    Update the workspace, removing and adding any repositories as needed
+    add                Add a provider to the configuration
+    fetch              Fetch new commits for all repositories in the workspace
+    help               Prints this message or the help of the given subcommand(s)
+    list               List all repositories in the workspace
+    run                Run a git command in all repositories
+    switch-and-pull    Pull new commits on the primary branch for all repositories in the workspace
+    update             Update the workspace, removing and adding any repositories as needed
 ```
 
 ## Define your workspace

src/main.rs

@@ -61,6 +61,11 @@ enum Command {
         #[structopt(short = "t", long = "threads", default_value = "8")]
         threads: usize,
     },
+    /// Pull new commits on the primary branch for all repositories in the workspace
+    SwitchAndPull {
+        #[structopt(short = "t", long = "threads", default_value = "8")]
+        threads: usize,
+    },
     /// List all repositories in the workspace
     ///
     /// This command will output the names of all known repositories in the workspace.
@@ -161,6 +166,7 @@ fn handle_main(args: Args) -> anyhow::Result<()> {
             command,
             args,
         } => execute_cmd(&workspace_path, threads, command, args)?,
+        Command::SwitchAndPull { threads } => pull_all_repositories(&workspace_path, threads)?,
     };
     Ok(())
 }
@@ -216,6 +222,34 @@ fn update(workspace: &PathBuf, threads: usize) -> anyhow::Result<()> {
     Ok(())
 }
 
+fn pull_all_repositories(workspace: &PathBuf, threads: usize) -> anyhow::Result<()> {
+    let lockfile = Lockfile::new(workspace.join("workspace-lock.toml"));
+    let repositories = lockfile.read().with_context(|| "Error reading lockfile")?;
+
+    println!(
+        "Switching to the primary branch and pulling {} repositories",
+        repositories.len()
+    );
+
+    map_repositories(&repositories, threads, |r, progress_bar| {
+        r.switch_to_primary_branch(&workspace)?;
+        let pull_args = match (&r.upstream, &r.branch) {
+            // This fucking sucks, but it's because my abstractions suck ass.
+            // I need to learn how to fix this.
+            (Some(_), Some(branch)) => vec![
+                "pull".to_string(),
+                "upstream".to_string(),
+                branch.to_string(),
+            ],
+            _ => vec!["pull".to_string()],
+        };
+        r.execute_cmd(&workspace, &progress_bar, "git", &pull_args)?;
+        Ok(())
+    })?;
+
+    Ok(())
+}
+
 /// Execute a command on all our repositories
 fn execute_cmd(
     workspace: &PathBuf,
@@ -410,7 +444,6 @@ where
             eprintln!("{}:", repo.name());
             error
                 .chain()
-                .skip(1)
                 .for_each(|cause| eprintln!("because: {}", cause));
         }
     }

src/repository.rs

@@ -1,5 +1,7 @@
 use anyhow::{anyhow, Context};
 use console::{strip_ansi_codes, truncate_str};
+use git2::build::CheckoutBuilder;
+use git2::{Repository as Git2Repository, StatusOptions};
 use indicatif::ProgressBar;
 use serde::{Deserialize, Serialize};
 use std::io::{BufRead, BufReader};
@@ -11,8 +13,8 @@ use std::process::{Command, Stdio};
 pub struct Repository {
     path: String,
     url: String,
-    upstream: Option<String>,
-    branch: Option<String>,
+    pub upstream: Option<String>,
+    pub branch: Option<String>,
 }
 
 impl Repository {
@@ -38,6 +40,7 @@ impl Repository {
             upstream,
         }
     }
+
     pub fn set_upstream(&self, root: &PathBuf) -> anyhow::Result<()> {
         let upstream = match &self.upstream {
             Some(upstream) => upstream,
@@ -137,6 +140,26 @@ impl Repository {
         Ok(())
     }
 
+    pub fn switch_to_primary_branch(&self, root: &PathBuf) -> anyhow::Result<()> {
+        let branch = match &self.branch {
+            None => return Ok(()),
+            Some(b) => b,
+        };
+        let repo = Git2Repository::init(root.join(&self.name()))?;
+        let status = repo.statuses(Some(&mut StatusOptions::default()))?;
+        if !status.is_empty() {
+            return Err(anyhow!(
+                "Repository is dirty, cannot switch to branch {}",
+                branch
+            ));
+        }
+        repo.set_head(&format!("refs/heads/{}", branch).to_string())
+            .with_context(|| format!("Cannot find branch {}", branch))?;
+        repo.checkout_head(Some(CheckoutBuilder::default().safe().force()))
+            .with_context(|| format!("Error checking out branch {}", branch))?;
+        Ok(())
+    }
+
     pub fn clone(&self, root: &PathBuf, progress_bar: &ProgressBar) -> anyhow::Result<()> {
         let mut command = Command::new("git");