Extract Clojure support into an extension (#10088)

This PR extracts Clojure support into an extension and removes the
built-in Clojure support from Zed.

Release Notes:

- Removed built-in support for Clojure, in favor of making it available
as an extension. The Clojure extension will be suggested for download
when you open a `.clj` or other Clojure-related files.

---------

Co-authored-by: Max <max@zed.dev>

extensions/clojure/Cargo.toml

@@ -0,0 +1,16 @@
+[package]
+name = "zed_clojure"
+version = "0.0.1"
+edition = "2021"
+publish = false
+license = "Apache-2.0"
+
+[lints]
+workspace = true
+
+[lib]
+path = "src/clojure.rs"
+crate-type = ["cdylib"]
+
+[dependencies]
+zed_extension_api = "0.0.4"

extensions/clojure/extension.toml

@@ -0,0 +1,15 @@
+id = "clojure"
+name = "Clojure"
+description = "Clojure support."
+version = "0.0.1"
+schema_version = 1
+authors = ["Paulo Roberto de Oliveira Castro <p.oliveira.castro@gmail.com>"]
+repository = "https://github.com/zed-industries/zed"
+
+[language_servers.clojure-lsp]
+name = "clojure-lsp"
+language = "Clojure"
+
+[grammars.clojure]
+repository = "https://github.com/prcastro/tree-sitter-clojure"
+commit = "38b4f8d264248b2fd09575fbce66f7c22e8929d5"

extensions/clojure/languages/clojure/brackets.scm

@@ -0,0 +1,3 @@
+("(" @open ")" @close)
+("[" @open "]" @close)
+("{" @open "}" @close)

extensions/clojure/languages/clojure/config.toml

@@ -0,0 +1,12 @@
+name = "Clojure"
+grammar = "clojure"
+path_suffixes = ["clj", "cljs", "cljc", "edn", "bb"]
+line_comments = [";; "]
+autoclose_before = "}])"
+brackets = [
+    { start = "{", end = "}", close = true, newline = true },
+    { start = "[", end = "]", close = true, newline = true },
+    { start = "(", end = ")", close = true, newline = true },
+    { start = "\"", end = "\"", close = true, newline = false, not_in = ["string"] },
+]
+word_characters = ["-"]

extensions/clojure/languages/clojure/highlights.scm

@@ -0,0 +1,41 @@
+;; Literals
+
+(num_lit) @number
+
+[
+  (char_lit)
+  (str_lit)
+] @string
+
+[
+ (bool_lit)
+ (nil_lit)
+] @constant.builtin
+
+(kwd_lit) @constant
+
+;; Comments
+
+(comment) @comment
+
+;; Treat quasiquotation as operators for the purpose of highlighting.
+
+[
+ "'"
+ "`"
+ "~"
+ "@"
+ "~@"
+] @operator
+
+
+(list_lit
+  .
+  (sym_lit) @function)
+
+(list_lit
+  .
+  (sym_lit) @keyword
+  (#match? @keyword
+    "^(do|if|let|var|fn|fn*|loop*|recur|throw|try|catch|finally|set!|new|quote|->|->>)$"
+    ))

extensions/clojure/languages/clojure/indents.scm

@@ -0,0 +1,3 @@
+(_ "[" "]") @indent
+(_ "{" "}") @indent
+(_ "(" ")") @indent

extensions/clojure/languages/clojure/outline.scm

@@ -0,0 +1 @@
+

extensions/clojure/src/clojure.rs

@@ -0,0 +1,110 @@
+use std::fs;
+use zed_extension_api::{self as zed, Result};
+
+struct ClojureExtension {
+    cached_binary_path: Option<String>,
+}
+
+impl ClojureExtension {
+    fn language_server_binary_path(
+        &mut self,
+        config: zed::LanguageServerConfig,
+        worktree: &zed::Worktree,
+    ) -> Result<String> {
+        if let Some(path) = &self.cached_binary_path {
+            if fs::metadata(path).map_or(false, |stat| stat.is_file()) {
+                return Ok(path.clone());
+            }
+        }
+
+        if let Some(path) = worktree.which("clojure-lsp") {
+            self.cached_binary_path = Some(path.clone());
+            return Ok(path);
+        }
+
+        zed::set_language_server_installation_status(
+            &config.name,
+            &zed::LanguageServerInstallationStatus::CheckingForUpdate,
+        );
+        let release = zed::latest_github_release(
+            "clojure-lsp/clojure-lsp",
+            zed::GithubReleaseOptions {
+                require_assets: true,
+                pre_release: false,
+            },
+        )?;
+
+        let (platform, arch) = zed::current_platform();
+        let asset_name = format!(
+            "clojure-lsp-native-{os}-{arch}.zip",
+            os = match platform {
+                zed::Os::Mac => "macos",
+                zed::Os::Linux => "linux",
+                zed::Os::Windows => "windows",
+            },
+            arch = match arch {
+                zed::Architecture::Aarch64 => "aarch64",
+                zed::Architecture::X8664 => "amd64",
+                zed::Architecture::X86 =>
+                    return Err(format!("unsupported architecture: {arch:?}")),
+            },
+        );
+
+        let asset = release
+            .assets
+            .iter()
+            .find(|asset| asset.name == asset_name)
+            .ok_or_else(|| format!("no asset found matching {:?}", asset_name))?;
+
+        let version_dir = format!("clojure-lsp-{}", release.version);
+        let binary_path = format!("{version_dir}/clojure-lsp");
+
+        if !fs::metadata(&binary_path).map_or(false, |stat| stat.is_file()) {
+            zed::set_language_server_installation_status(
+                &config.name,
+                &zed::LanguageServerInstallationStatus::Downloading,
+            );
+
+            zed::download_file(
+                &asset.download_url,
+                &version_dir,
+                zed::DownloadedFileType::Zip,
+            )
+            .map_err(|e| format!("failed to download file: {e}"))?;
+
+            let entries =
+                fs::read_dir(".").map_err(|e| format!("failed to list working directory {e}"))?;
+            for entry in entries {
+                let entry = entry.map_err(|e| format!("failed to load directory entry {e}"))?;
+                if entry.file_name().to_str() != Some(&version_dir) {
+                    fs::remove_dir_all(&entry.path()).ok();
+                }
+            }
+        }
+
+        self.cached_binary_path = Some(binary_path.clone());
+        Ok(binary_path)
+    }
+}
+
+impl zed::Extension for ClojureExtension {
+    fn new() -> Self {
+        Self {
+            cached_binary_path: None,
+        }
+    }
+
+    fn language_server_command(
+        &mut self,
+        config: zed::LanguageServerConfig,
+        worktree: &zed::Worktree,
+    ) -> Result<zed::Command> {
+        Ok(zed::Command {
+            command: self.language_server_binary_path(config, worktree)?,
+            args: Vec::new(),
+            env: Default::default(),
+        })
+    }
+}
+
+zed::register_extension!(ClojureExtension);