feat Add PowerShell support (#2543)

This adds PowerShell support 🎉 

I built this script around @lzybkr's
[prototype](https://github.com/atuinsh/atuin/issues/84#issuecomment-1689168533),
so I added him as co-author (I hope that's ok). I wouldn't know where to
start without his contribution.

I'm not a PowerShell expert, so this was a nice opportunity to learn
some stuff. I think it's ok, but I would appreciate if someone more
knowledgeable in the matter could review this though.

It would be nice if other PowerShell users could test this with their
configs and report any issues. I wouldn't be surprised if there are some
remaining bugs or missing features.

Fixes #84

## Installation

If you'd like to test this, you can install the `atuin` from this PR by
running:

```powershell
cargo install --git https://github.com/ltrzesniewski/atuin.git --branch powershell-pr
```

Then, add the following to your PowerShell profile file (whose path is
in `$PROFILE`) and restart the shell:

```powershell
atuin init powershell | Out-String | Invoke-Expression
```

This requires `atuin` to be in the path and the
[PSReadLine](https://github.com/PowerShell/PSReadLine) module to be
installed, which is the case by default.

## Tests

I tested this on the following:
- PowerShell 7.4.6 / PSReadLine 2.3.5 / Windows (the latest one)
- PowerShell 7.5.1 / PSReadLine 2.3.6 / Windows (the latest one)
- PowerShell 5.1.22621.4391 / PSReadLine 2.0.0 / Windows (the one
shipped with Windows)
- PowerShell 7.4.6 / PSReadLine 2.3.5 / Ubuntu WSL (strangely, it didn't
behave exactly like the Windows version)
- PowerShell 7.5.1 / PSReadLine 2.3.6 / Ubuntu WSL

I also tested this with and without my custom [Oh My
Posh](https://ohmyposh.dev/) prompt. It works fine in both cases,
~except that since my OMP config contains `"newline": true`, my prompt
is multiline and shifts downwards by a single line on each `atuin search
-i` invocation. This can be adjusted with the
`$env:ATUIN_POWERSHELL_PROMPT_OFFSET` environment variable (e.g. I set
mine to `-1` to account for the additional prompt line).~ (this variable
is now auto-initialized).

## Checks
- [x] I am happy for maintainers to push small adjustments to this PR,
to speed up the review cycle
- [x] I have checked that there are no existing pull requests for the
same thing

---------

Co-authored-by: Jason Shirk <jasonsh@microsoft.com>

1 files changed, 41 insertions, 12 deletions

diff --git a/crates/atuin-dotfiles/src/store/var.rs b/crates/atuin-dotfiles/src/store/var.rs
index 402ba684..9d25b85d 100644
--- a/crates/atuin-dotfiles/src/store/var.rs
+++ b/crates/atuin-dotfiles/src/store/var.rs
@@ -169,7 +169,25 @@ impl VarStore {
 
     pub async fn xonsh(&self) -> Result<String> {
         let env = self.vars().await?;
+        Ok(Self::format_xonsh(&env))
+    }
 
+    pub async fn fish(&self) -> Result<String> {
+        let env = self.vars().await?;
+        Ok(Self::format_fish(&env))
+    }
+
+    pub async fn posix(&self) -> Result<String> {
+        let env = self.vars().await?;
+        Ok(Self::format_posix(&env))
+    }
+
+    pub async fn powershell(&self) -> Result<String> {
+        let env = self.vars().await?;
+        Ok(Self::format_powershell(&env))
+    }
+
+    fn format_xonsh(env: &[Var]) -> String {
         let mut config = String::new();
 
         for env in env {
@@ -177,12 +195,10 @@ impl VarStore {
             config.push_str(&format!("${}={}\n", env.name, escaped_value));
         }
 
-        Ok(config)
+        config
     }
 
-    pub async fn fish(&self) -> Result<String> {
-        let env = self.vars().await?;
-
+    fn format_fish(env: &[Var]) -> String {
         let mut config = String::new();
 
         for env in env {
@@ -190,12 +206,10 @@ impl VarStore {
             config.push_str(&format!("set -gx {} {}\n", env.name, escaped_value));
         }
 
-        Ok(config)
+        config
     }
 
-    pub async fn posix(&self) -> Result<String> {
-        let env = self.vars().await?;
-
+    fn format_posix(env: &[Var]) -> String {
         let mut config = String::new();
 
         for env in env {
@@ -207,17 +221,30 @@ impl VarStore {
             }
         }
 
-        Ok(config)
+        config
+    }
+
+    fn format_powershell(env: &[Var]) -> String {
+        let mut config = String::new();
+
+        for var in env {
+            config.push_str(&crate::shell::powershell::format_var(var));
+        }
+
+        config
     }
 
     pub async fn build(&self) -> Result<()> {
         let dir = atuin_common::utils::dotfiles_cache_dir();
         tokio::fs::create_dir_all(dir.clone()).await?;
 
+        let env = self.vars().await?;
+
         // Build for all supported shells
-        let posix = self.posix().await?;
-        let xonsh = self.xonsh().await?;
-        let fsh = self.fish().await?;
+        let posix = Self::format_posix(&env);
+        let xonsh = Self::format_xonsh(&env);
+        let fsh = Self::format_fish(&env);
+        let powershell = Self::format_powershell(&env);
 
         // All the same contents, maybe optimize in the future or perhaps there will be quirks
         // per-shell
@@ -226,11 +253,13 @@ impl VarStore {
         let bash = dir.join("vars.bash");
         let fish = dir.join("vars.fish");
         let xsh = dir.join("vars.xsh");
+        let ps1 = dir.join("vars.ps1");
 
         tokio::fs::write(zsh, &posix).await?;
         tokio::fs::write(bash, &posix).await?;
         tokio::fs::write(fish, &fsh).await?;
         tokio::fs::write(xsh, &xonsh).await?;
+        tokio::fs::write(ps1, &powershell).await?;
 
         Ok(())
     }