Add ghcup step (#89)

src/config.rs

@@ -93,6 +93,7 @@ pub enum Step {
     Fossil,
     Gcloud,
     Gem,
+    Ghcup,
     GithubCliExtensions,
     GitRepos,
     Go,

src/main.rs

@@ -323,6 +323,7 @@ fn run() -> Result<()> {
     runner.execute(Step::Pipx, "pipx", || generic::run_pipx_update(run_type))?;
     runner.execute(Step::Conda, "conda", || generic::run_conda_update(&ctx))?;
     runner.execute(Step::Pip3, "pip3", || generic::run_pip3_update(run_type))?;
+    runner.execute(Step::Ghcup, "ghcup", || generic::run_ghcup_update(run_type))?;
     runner.execute(Step::Stack, "stack", || generic::run_stack_update(run_type))?;
     runner.execute(Step::Tlmgr, "tlmgr", || generic::run_tlmgr_update(&ctx))?;
     runner.execute(Step::Myrepos, "myrepos", || {

src/steps/generic.rs

@@ -289,12 +289,26 @@ pub fn run_pip3_update(run_type: RunType) -> Result<()> {
 }
 
 pub fn run_stack_update(run_type: RunType) -> Result<()> {
+    if let Ok(_) = utils::require("ghcup") {
+        // `ghcup` is present and probably(?) being used to install `stack`.
+        // Don't upgrade `stack`, let `ghcup` handle it. Per `ghcup install stack`:
+        // !!! Additionally, you should upgrade stack only through ghcup and not use 'stack upgrade' !!!
+        return Ok(());
+    }
+
     let stack = utils::require("stack")?;
     print_separator("stack");
 
     run_type.execute(&stack).arg("upgrade").check_run()
 }
 
+pub fn run_ghcup_update(run_type: RunType) -> Result<()> {
+    let ghcup = utils::require("ghcup")?;
+    print_separator("ghcup");
+
+    run_type.execute(&ghcup).arg("upgrade").check_run()
+}
+
 pub fn run_tlmgr_update(ctx: &ExecutionContext) -> Result<()> {
     cfg_if::cfg_if! {
         if #[cfg(any(target_os = "linux", target_os = "android"))] {