feat: support oh-my-bash (#425)

src/steps/os/unix.rs

@@ -2,7 +2,10 @@ use std::fs;
 use std::os::unix::fs::MetadataExt;
 use std::path::PathBuf;
 use std::process::Command;
-use std::{env, path::Path};
+use std::{
+    env::{self, var},
+    path::Path,
+};
 
 use crate::command::CommandExt;
 use crate::{Step, HOME_DIR};
@@ -136,6 +139,27 @@ pub fn run_bashit(ctx: &ExecutionContext) -> Result<()> {
         .status_checked()
 }
 
+pub fn run_oh_my_bash(ctx: &ExecutionContext) -> Result<()> {
+    require("bash")?;
+    let oh_my_bash = var("OSH")
+        // default to `~/.oh-my-bash`
+        .unwrap_or(
+            HOME_DIR
+                .join(".oh-my-bash")
+                .to_str()
+                .expect("should be UTF-8 encoded")
+                .to_string(),
+        )
+        .require()?;
+
+    print_separator("oh-my-bash");
+
+    let mut update_script = oh_my_bash;
+    update_script.push_str("tools/upgrade.sh");
+
+    ctx.run_type().execute("bash").arg(update_script).status_checked()
+}
+
 pub fn run_oh_my_fish(ctx: &ExecutionContext) -> Result<()> {
     let fish = require("fish")?;
     HOME_DIR.join(".local/share/omf/pkg/omf/functions/omf.fish").require()?;