1use std::fs;
  2use zed::lsp::CompletionKind;
  3use zed::{CodeLabel, CodeLabelSpan, LanguageServerId};
  4use zed_extension_api::{self as zed, Result};
  5
  6struct TestExtension {
  7    cached_binary_path: Option<String>,
  8}
  9
 10impl TestExtension {
 11    fn language_server_binary_path(
 12        &mut self,
 13        language_server_id: &LanguageServerId,
 14        _worktree: &zed::Worktree,
 15    ) -> Result<String> {
 16        if let Some(path) = &self.cached_binary_path {
 17            if fs::metadata(path).map_or(false, |stat| stat.is_file()) {
 18                return Ok(path.clone());
 19            }
 20        }
 21
 22        zed::set_language_server_installation_status(
 23            language_server_id,
 24            &zed::LanguageServerInstallationStatus::CheckingForUpdate,
 25        );
 26        let release = zed::latest_github_release(
 27            "gleam-lang/gleam",
 28            zed::GithubReleaseOptions {
 29                require_assets: true,
 30                pre_release: false,
 31            },
 32        )?;
 33
 34        let (platform, arch) = zed::current_platform();
 35        let asset_name = format!(
 36            "gleam-{version}-{arch}-{os}.tar.gz",
 37            version = release.version,
 38            arch = match arch {
 39                zed::Architecture::Aarch64 => "aarch64",
 40                zed::Architecture::X86 => "x86",
 41                zed::Architecture::X8664 => "x86_64",
 42            },
 43            os = match platform {
 44                zed::Os::Mac => "apple-darwin",
 45                zed::Os::Linux => "unknown-linux-musl",
 46                zed::Os::Windows => "pc-windows-msvc",
 47            },
 48        );
 49
 50        let asset = release
 51            .assets
 52            .iter()
 53            .find(|asset| asset.name == asset_name)
 54            .ok_or_else(|| format!("no asset found matching {:?}", asset_name))?;
 55
 56        let version_dir = format!("gleam-{}", release.version);
 57        let binary_path = format!("{version_dir}/gleam");
 58
 59        if !fs::metadata(&binary_path).map_or(false, |stat| stat.is_file()) {
 60            zed::set_language_server_installation_status(
 61                language_server_id,
 62                &zed::LanguageServerInstallationStatus::Downloading,
 63            );
 64
 65            zed::download_file(
 66                &asset.download_url,
 67                &version_dir,
 68                zed::DownloadedFileType::GzipTar,
 69            )
 70            .map_err(|e| format!("failed to download file: {e}"))?;
 71
 72            let entries =
 73                fs::read_dir(".").map_err(|e| format!("failed to list working directory {e}"))?;
 74            for entry in entries {
 75                let entry = entry.map_err(|e| format!("failed to load directory entry {e}"))?;
 76                if entry.file_name().to_str() != Some(&version_dir) {
 77                    fs::remove_dir_all(entry.path()).ok();
 78                }
 79            }
 80        }
 81
 82        self.cached_binary_path = Some(binary_path.clone());
 83        Ok(binary_path)
 84    }
 85}
 86
 87impl zed::Extension for TestExtension {
 88    fn new() -> Self {
 89        Self {
 90            cached_binary_path: None,
 91        }
 92    }
 93
 94    fn language_server_command(
 95        &mut self,
 96        language_server_id: &LanguageServerId,
 97        worktree: &zed::Worktree,
 98    ) -> Result<zed::Command> {
 99        Ok(zed::Command {
100            command: self.language_server_binary_path(language_server_id, worktree)?,
101            args: vec!["lsp".to_string()],
102            env: Default::default(),
103        })
104    }
105
106    fn label_for_completion(
107        &self,
108        _language_server_id: &LanguageServerId,
109        completion: zed::lsp::Completion,
110    ) -> Option<zed::CodeLabel> {
111        let name = &completion.label;
112        let ty = strip_newlines_from_detail(&completion.detail?);
113        let let_binding = "let a";
114        let colon = ": ";
115        let assignment = " = ";
116        let call = match completion.kind? {
117            CompletionKind::Function | CompletionKind::Constructor => "()",
118            _ => "",
119        };
120        let code = format!("{let_binding}{colon}{ty}{assignment}{name}{call}");
121
122        Some(CodeLabel {
123            spans: vec![
124                CodeLabelSpan::code_range({
125                    let start = let_binding.len() + colon.len() + ty.len() + assignment.len();
126                    start..start + name.len()
127                }),
128                CodeLabelSpan::code_range({
129                    let start = let_binding.len();
130                    start..start + colon.len()
131                }),
132                CodeLabelSpan::code_range({
133                    let start = let_binding.len() + colon.len();
134                    start..start + ty.len()
135                }),
136            ],
137            filter_range: (0..name.len()).into(),
138            code,
139        })
140    }
141}
142
143zed::register_extension!(TestExtension);
144
145/// Removes newlines from the completion detail.
146///
147/// The Gleam LSP can return types containing newlines, which causes formatting
148/// issues within the Zed completions menu.
149fn strip_newlines_from_detail(detail: &str) -> String {
150    let without_newlines = detail
151        .replace("->\n  ", "-> ")
152        .replace("\n  ", "")
153        .replace(",\n", "");
154
155    let comma_delimited_parts = without_newlines.split(',');
156    comma_delimited_parts
157        .map(|part| part.trim())
158        .collect::<Vec<_>>()
159        .join(", ")
160}