Fix issues with extension API that come up when moving Svelte into an extension (#9611)

We're doing it. Svelte support is moving into an extension. This PR
fixes some issues that came up along the way.

Notes

* extensions need to be able to retrieve the path the `node` binary
installed by Zed
* previously we were silently swallowing any errors that occurred while
loading a grammar
* npm commands ran by extensions weren't run in the right directory
* Tree-sitter's WASM stdlib didn't support a C function (`strncmp`)
needed by the Svelte parser's external scanner
* the way that LSP installation status was reported was unnecessarily
complex

Release Notes:

- Removed built-in support for the Svelte and Gleam languages, because
full support for those languages is now available via extensions. These
extensions will be suggested for download when you open a `.svelte` or
`.gleam` file.

---------

Co-authored-by: Marshall <marshall@zed.dev>

extensions/gleam/Cargo.toml

@@ -8,9 +8,9 @@ license = "Apache-2.0"
 [lints]
 workspace = true
 
-[dependencies]
-zed_extension_api = { path = "../../crates/extension_api" }
-
 [lib]
 path = "src/gleam.rs"
 crate-type = ["cdylib"]
+
+[dependencies]
+zed_extension_api = "0.0.4"

extensions/gleam/src/gleam.rs

@@ -9,10 +9,6 @@ impl GleamExtension {
     fn language_server_binary_path(&mut self, config: zed::LanguageServerConfig) -> Result<String> {
         if let Some(path) = &self.cached_binary_path {
             if fs::metadata(path).map_or(false, |stat| stat.is_file()) {
-                zed::set_language_server_installation_status(
-                    &config.name,
-                    &zed::LanguageServerInstallationStatus::Cached,
-                );
                 return Ok(path.clone());
             }
         }
@@ -75,11 +71,6 @@ impl GleamExtension {
                     fs::remove_dir_all(&entry.path()).ok();
                 }
             }
-
-            zed::set_language_server_installation_status(
-                &config.name,
-                &zed::LanguageServerInstallationStatus::Downloaded,
-            );
         }
 
         self.cached_binary_path = Some(binary_path.clone());

extensions/svelte/.gitignore

@@ -0,0 +1,3 @@
+target
+*.wasm
+grammars

extensions/svelte/Cargo.toml

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

extensions/svelte/extension.toml

@@ -0,0 +1,15 @@
+id = "svelte"
+name = "Svelte"
+description = "Svelte support"
+version = "0.0.1"
+schema_version = 1
+authors = []
+repository = "https://github.com/zed-extensions/svelte"
+
+[language_servers.svelte-language-server]
+name = "Svelte Language Server"
+language = "Svelte"
+
+[grammars.svelte]
+repository = "https://github.com/Himujjal/tree-sitter-svelte"
+commit = "ea528fc9985aed8d93c9f438c185644a33d011af"

extensions/svelte/languages/svelte/config.toml

@@ -0,0 +1,22 @@
+name = "Svelte"
+grammar = "svelte"
+path_suffixes = ["svelte"]
+block_comment = ["<!-- ", " -->"]
+autoclose_before = ";:.,=}])>"
+brackets = [
+    { start = "{", end = "}", close = true, newline = true },
+    { start = "[", end = "]", close = true, newline = true },
+    { start = "(", end = ")", close = true, newline = true },
+    { start = "<", end = ">", close = false, newline = true, not_in = ["string", "comment"] },
+    { start = "\"", end = "\"", close = true, newline = false, not_in = ["string"] },
+    { start = "'", end = "'", close = true, newline = false, not_in = ["string", "comment"] },
+    { start = "`", end = "`", close = true, newline = false, not_in = ["string"] },
+    { start = "/*", end = " */", close = true, newline = false, not_in = ["string", "comment"] },
+]
+scope_opt_in_language_servers = ["tailwindcss-language-server"]
+prettier_parser_name = "svelte"
+prettier_plugins = ["prettier-plugin-svelte"]
+
+[overrides.string]
+word_characters = ["-"]
+opt_into_language_servers = ["tailwindcss-language-server"]

extensions/svelte/languages/svelte/highlights.scm

@@ -0,0 +1,42 @@
+; Special identifiers
+;--------------------
+
+; TODO:
+(tag_name) @tag
+(attribute_name) @property
+(erroneous_end_tag_name) @keyword
+(comment) @comment
+
+[
+  (attribute_value)
+  (quoted_attribute_value)
+] @string
+
+[
+  (text)
+  (raw_text_expr)
+] @none
+
+[
+  (special_block_keyword)
+  (then)
+  (as)
+] @keyword
+
+[
+  "{"
+  "}"
+] @punctuation.bracket
+
+"=" @operator
+
+[
+  "<"
+  ">"
+  "</"
+  "/>"
+  "#"
+  ":"
+  "/"
+  "@"
+] @tag.delimiter

extensions/svelte/languages/svelte/indents.scm

@@ -0,0 +1,8 @@
+[
+  (element)
+  (if_statement)
+  (each_statement)
+  (await_statement)
+  (script_element)
+  (style_element)
+] @indent

extensions/svelte/languages/svelte/injections.scm

@@ -0,0 +1,32 @@
+; injections.scm
+; --------------
+((script_element
+    (start_tag
+      (attribute
+        (quoted_attribute_value (attribute_value) @_language))?)
+     (raw_text) @content)
+  (#eq? @_language "")
+  (#set! "language" "javascript"))
+
+ ((script_element
+     (start_tag
+       (attribute
+         (quoted_attribute_value (attribute_value) @_language)))
+      (raw_text) @content)
+    (#eq? @_language "ts")
+    (#set! "language" "typescript"))
+
+((script_element
+    (start_tag
+        (attribute
+        (quoted_attribute_value (attribute_value) @_language)))
+    (raw_text) @content)
+  (#eq? @_language "typescript")
+  (#set! "language" "typescript"))
+
+(style_element
+  (raw_text) @content
+  (#set! "language" "css"))
+
+((raw_text_expr) @content
+  (#set! "language" "javascript"))

extensions/svelte/languages/svelte/overrides.scm

@@ -0,0 +1,7 @@
+(comment) @comment
+
+[
+  (raw_text)
+  (attribute_value)
+  (quoted_attribute_value)
+] @string

extensions/svelte/src/svelte.rs

@@ -0,0 +1,126 @@
+use std::{env, fs};
+use zed_extension_api::{self as zed, Result};
+
+struct SvelteExtension {
+    did_find_server: bool,
+}
+
+const SERVER_PATH: &str = "node_modules/svelte-language-server/bin/server.js";
+const PACKAGE_NAME: &str = "svelte-language-server";
+
+impl SvelteExtension {
+    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 SvelteExtension {
+    fn new() -> Self {
+        Self {
+            did_find_server: false,
+        }
+    }
+
+    fn language_server_command(
+        &mut self,
+        config: zed::LanguageServerConfig,
+        _: &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,
+        _: zed::LanguageServerConfig,
+        _: &zed::Worktree,
+    ) -> Result<Option<String>> {
+        let config = r#"{
+          "inlayHints": {
+            "parameterNames": {
+              "enabled": "all",
+              "suppressWhenArgumentMatchesName": false
+            },
+            "parameterTypes": {
+              "enabled": true
+            },
+            "variableTypes": {
+              "enabled": true,
+              "suppressWhenTypeMatchesName": false
+            },
+            "propertyDeclarationTypes": {
+              "enabled": true
+            },
+            "functionLikeReturnType": {
+              "enabled": true
+            },
+            "enumMemberValues": {
+              "enabled": true
+            }
+          }
+        }"#;
+
+        Ok(Some(format!(
+            r#"{{
+                "provideFormatter": true,
+                "configuration": {{
+                    "typescript": {config},
+                    "javascript": {config}
+                }}
+            }}"#
+        )))
+    }
+}
+
+zed::register_extension!(SvelteExtension);

extensions/uiua/Cargo.toml

@@ -8,9 +8,9 @@ license = "Apache-2.0"
 [lints]
 workspace = true
 
-[dependencies]
-zed_extension_api = { path = "../../crates/extension_api" }
-
 [lib]
 path = "src/uiua.rs"
 crate-type = ["cdylib"]
+
+[dependencies]
+zed_extension_api = "0.0.4"