Extract PureScript support into an extension (#9824)

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

Release Notes:

- Removed built-in support for PureScript, in favor of making it
available as an extension. The PureScript extension will be suggested
for download when you open a `.purs` file.

extensions/purescript/Cargo.toml

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

extensions/purescript/LICENSE-APACHE

@@ -0,0 +1 @@
+../../LICENSE-APACHE

extensions/purescript/extension.toml

@@ -0,0 +1,15 @@
+id = "purescript"
+name = "PureScript"
+description = "PureScript support."
+version = "0.0.1"
+schema_version = 1
+authors = ["Iván Molina Rebolledo <ivanmolinarebolledo@gmail.com>"]
+repository = "https://github.com/zed-industries/zed"
+
+[language_servers.purescript-language-server]
+name = "PureScript Language Server"
+language = "PureScript"
+
+[grammars.purescript]
+repository = "https://github.com/postsolar/tree-sitter-purescript"
+commit = "0554811a512b9cec08b5a83ce9096eb22da18213"

extensions/purescript/languages/purescript/brackets.scm

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

extensions/purescript/languages/purescript/config.toml

@@ -0,0 +1,14 @@
+name = "PureScript"
+grammar = "purescript"
+path_suffixes = ["purs"]
+autoclose_before = ",=)}]"
+line_comments = ["-- "]
+block_comment = ["{- ", " -}"]
+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 },
+    { start = "'", end = "'", close = true, newline = false },
+    { start = "`", end = "`", close = true, newline = false },
+]

extensions/purescript/languages/purescript/highlights.scm

@@ -0,0 +1,144 @@
+;; Copyright 2022 nvim-treesitter
+;;
+;; Licensed under the Apache License, Version 2.0 (the "License");
+;; you may not use this file except in compliance with the License.
+;; You may obtain a copy of the License at
+;;
+;;     http://www.apache.org/licenses/LICENSE-2.0
+;;
+;; Unless required by applicable law or agreed to in writing, software
+;; distributed under the License is distributed on an "AS IS" BASIS,
+;; WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+;; See the License for the specific language governing permissions and
+;; limitations under the License.
+
+;; ----------------------------------------------------------------------------
+;; Literals and comments
+
+(integer) @number
+(exp_negation) @number
+(exp_literal (number)) @float
+(char) @character
+[
+  (string)
+  (triple_quote_string)
+] @string
+
+(comment) @comment
+
+
+;; ----------------------------------------------------------------------------
+;; Punctuation
+
+[
+  "("
+  ")"
+  "{"
+  "}"
+  "["
+  "]"
+] @punctuation.bracket
+
+[
+  (comma)
+  ";"
+] @punctuation.delimiter
+
+
+;; ----------------------------------------------------------------------------
+;; Keywords, operators, includes
+
+[
+  "forall"
+  "∀"
+] @keyword
+
+;; (pragma) @constant
+
+[
+  "if"
+  "then"
+  "else"
+  "case"
+  "of"
+] @keyword
+
+[
+  "import"
+  "module"
+] @keyword
+
+[
+  (operator)
+  (constructor_operator)
+  (type_operator)
+  (qualified_module)  ; grabs the `.` (dot), ex: import System.IO
+  (all_names)
+  (wildcard)
+  "="
+  "|"
+  "::"
+  "=>"
+  "->"
+  "<-"
+  "\\"
+  "`"
+  "@"
+  "∷"
+  "⇒"
+  "<="
+  "⇐"
+  "→"
+  "←"
+] @operator
+
+(module) @title
+
+[
+  (where)
+  "let"
+  "in"
+  "class"
+  "instance"
+  "derive"
+  "foreign"
+  "data"
+  "newtype"
+  "type"
+  "as"
+  "hiding"
+  "do"
+  "ado"
+  "infix"
+  "infixl"
+  "infixr"
+] @keyword
+
+
+;; ----------------------------------------------------------------------------
+;; Functions and variables
+
+(variable) @variable
+(pat_wildcard) @variable
+
+(signature name: (variable) @type)
+(function
+  name: (variable) @function
+  patterns: (patterns))
+
+
+(exp_infix (exp_name) @function (#set! "priority" 101))
+(exp_apply . (exp_name (variable) @function))
+(exp_apply . (exp_name (qualified_variable (variable) @function)))
+
+
+;; ----------------------------------------------------------------------------
+;; Types
+
+(type) @type
+(type_variable) @type
+
+(constructor) @constructor
+
+; True or False
+((constructor) @_bool (#match? @_bool "(True|False)")) @boolean

extensions/purescript/languages/purescript/indents.scm

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

extensions/purescript/src/purescript.rs

@@ -0,0 +1,99 @@
+use std::{env, fs};
+use zed_extension_api::{self as zed, Result};
+
+const SERVER_PATH: &str = "node_modules/.bin/purescript-language-server";
+const PACKAGE_NAME: &str = "purescript-language-server";
+
+struct PrismaExtension {
+    did_find_server: bool,
+}
+
+impl PrismaExtension {
+    fn server_exists(&self) -> bool {
+        fs::metadata(SERVER_PATH).map_or(false, |stat| stat.is_file())
+    }
+
+    fn server_script_path(&mut self, config: zed::LanguageServerConfig) -> Result<String> {
+        let server_exists = self.server_exists();
+        if self.did_find_server && server_exists {
+            return Ok(SERVER_PATH.to_string());
+        }
+
+        zed::set_language_server_installation_status(
+            &config.name,
+            &zed::LanguageServerInstallationStatus::CheckingForUpdate,
+        );
+        let version = zed::npm_package_latest_version(PACKAGE_NAME)?;
+
+        if !server_exists
+            || zed::npm_package_installed_version(PACKAGE_NAME)?.as_ref() != Some(&version)
+        {
+            zed::set_language_server_installation_status(
+                &config.name,
+                &zed::LanguageServerInstallationStatus::Downloading,
+            );
+            let result = zed::npm_install_package(PACKAGE_NAME, &version);
+            match result {
+                Ok(()) => {
+                    if !self.server_exists() {
+                        Err(format!(
+                            "installed package '{PACKAGE_NAME}' did not contain expected path '{SERVER_PATH}'",
+                        ))?;
+                    }
+                }
+                Err(error) => {
+                    if !self.server_exists() {
+                        Err(error)?;
+                    }
+                }
+            }
+        }
+
+        self.did_find_server = true;
+        Ok(SERVER_PATH.to_string())
+    }
+}
+
+impl zed::Extension for PrismaExtension {
+    fn new() -> Self {
+        Self {
+            did_find_server: false,
+        }
+    }
+
+    fn language_server_command(
+        &mut self,
+        config: zed::LanguageServerConfig,
+        _worktree: &zed::Worktree,
+    ) -> Result<zed::Command> {
+        let server_path = self.server_script_path(config)?;
+        Ok(zed::Command {
+            command: zed::node_binary_path()?,
+            args: vec![
+                env::current_dir()
+                    .unwrap()
+                    .join(&server_path)
+                    .to_string_lossy()
+                    .to_string(),
+                "--stdio".to_string(),
+            ],
+            env: Default::default(),
+        })
+    }
+
+    fn language_server_initialization_options(
+        &mut self,
+        _config: zed::LanguageServerConfig,
+        _worktree: &zed::Worktree,
+    ) -> Result<Option<String>> {
+        let initialization_options = r#"{
+            "purescript": {
+                "addSpagoSources": true
+            }
+        }"#;
+
+        Ok(Some(initialization_options.to_string()))
+    }
+}
+
+zed::register_extension!(PrismaExtension);