Added support for antigen (#231)

README.md

@@ -77,6 +77,7 @@ Just run `topgrade`. It will run the following steps:
 * **Unix**: Run [zr](https://github.com/jedahan/zr) update
 * **Unix**: Run [zplug](https://github.com/zplug/zplug) update
 * **Unix**: Run [oh-my-zsh](https://github.com/robbyrussell/oh-my-zsh) update
+* **Unix**: Run [antigen](https://github.com/zsh-users/antigen) update
 * **Unix**: Run [fisher](https://github.com/jorgebucaran/fisher)
 * **Unix**: Upgrade tmux plugins with [TPM](https://github.com/tmux-plugins/tpm). *Note*: Do not use
   the `-b` flag in your configuration as suggested by the TPM readme.

src/main.rs

@@ -285,6 +285,12 @@ fn run() -> Result<(), Error> {
                 || unix::run_zr(&base_dirs, run_type),
                 config.no_retry(),
             )?;
+            execute(
+                &mut report,
+                "antigen",
+                || unix::run_antigen(&base_dirs, run_type),
+                config.no_retry(),
+            )?;
             execute(
                 &mut report,
                 "zplug",

src/steps/os/unix.rs

@@ -27,6 +27,20 @@ fn zshrc(base_dirs: &BaseDirs) -> PathBuf {
         .unwrap_or_else(|_| base_dirs.home_dir().join(".zshrc"))
 }
 
+pub fn run_antigen(base_dirs: &BaseDirs, run_type: RunType) -> Result<(), Error> {
+    let zsh = require("zsh")?;
+    let zshrc = zshrc(base_dirs).require()?;
+    env::var("ADOTDIR")
+        .map(PathBuf::from)
+        .unwrap_or_else(|_| base_dirs.home_dir().join("antigen.zsh"))
+        .require()?;
+
+    print_separator("antigen");
+
+    let cmd = format!("source {} && antigen selfupdate && antigen update", zshrc.display());
+    run_type.execute(zsh).args(&["-c", cmd.as_str()]).check_run()
+}
+
 pub fn run_zplug(base_dirs: &BaseDirs, run_type: RunType) -> Result<(), Error> {
     let zsh = require("zsh")?;
     let zshrc = zshrc(base_dirs).require()?;