feat: REPL import specifier auto-completions (#13078)

1 files changed, 297 insertions, 0 deletions

diff --git a/cli/lsp/repl.rs b/cli/lsp/repl.rs
new file mode 100644
index 000000000..458841c19
--- /dev/null
+++ b/cli/lsp/repl.rs
@@ -0,0 +1,297 @@
+// Copyright 2018-2021 the Deno authors. All rights reserved. MIT license.
+
+use std::collections::HashMap;
+use std::future::Future;
+
+use deno_ast::swc::common::BytePos;
+use deno_ast::swc::common::Span;
+use deno_ast::LineAndColumnIndex;
+use deno_ast::ModuleSpecifier;
+use deno_ast::SourceTextInfo;
+use deno_core::anyhow::anyhow;
+use deno_core::error::AnyError;
+use deno_core::serde_json;
+use lspower::lsp::ClientCapabilities;
+use lspower::lsp::ClientInfo;
+use lspower::lsp::CompletionContext;
+use lspower::lsp::CompletionParams;
+use lspower::lsp::CompletionResponse;
+use lspower::lsp::CompletionTextEdit;
+use lspower::lsp::CompletionTriggerKind;
+use lspower::lsp::DidChangeTextDocumentParams;
+use lspower::lsp::DidCloseTextDocumentParams;
+use lspower::lsp::DidOpenTextDocumentParams;
+use lspower::lsp::InitializeParams;
+use lspower::lsp::InitializedParams;
+use lspower::lsp::PartialResultParams;
+use lspower::lsp::Position;
+use lspower::lsp::Range;
+use lspower::lsp::TextDocumentContentChangeEvent;
+use lspower::lsp::TextDocumentIdentifier;
+use lspower::lsp::TextDocumentItem;
+use lspower::lsp::TextDocumentPositionParams;
+use lspower::lsp::VersionedTextDocumentIdentifier;
+use lspower::lsp::WorkDoneProgressParams;
+use lspower::LanguageServer;
+
+use crate::logger;
+
+use super::client::Client;
+use super::config::CompletionSettings;
+use super::config::ImportCompletionSettings;
+use super::config::WorkspaceSettings;
+
+#[derive(Debug)]
+pub struct ReplCompletionItem {
+  pub new_text: String,
+  pub span: Span,
+}
+
+pub struct ReplLanguageServer {
+  language_server: super::language_server::LanguageServer,
+  document_version: i32,
+  document_text: String,
+  pending_text: String,
+  cwd_uri: ModuleSpecifier,
+}
+
+impl ReplLanguageServer {
+  pub async fn new_initialized() -> Result<ReplLanguageServer, AnyError> {
+    super::logging::set_lsp_log_level(log::Level::Debug);
+    let language_server =
+      super::language_server::LanguageServer::new(Client::new_for_repl());
+
+    let cwd_uri = get_cwd_uri()?;
+
+    #[allow(deprecated)]
+    language_server
+      .initialize(InitializeParams {
+        process_id: None,
+        root_path: None,
+        root_uri: Some(cwd_uri.clone()),
+        initialization_options: Some(
+          serde_json::to_value(get_repl_workspace_settings()).unwrap(),
+        ),
+        capabilities: ClientCapabilities {
+          workspace: None,
+          text_document: None,
+          window: None,
+          general: None,
+          experimental: None,
+        },
+        trace: None,
+        workspace_folders: None,
+        client_info: Some(ClientInfo {
+          name: "Deno REPL".to_string(),
+          version: None,
+        }),
+        locale: None,
+      })
+      .await?;
+
+    language_server.initialized(InitializedParams {}).await;
+
+    let server = ReplLanguageServer {
+      language_server,
+      document_version: 0,
+      document_text: String::new(),
+      pending_text: String::new(),
+      cwd_uri,
+    };
+    server.open_current_document().await;
+
+    Ok(server)
+  }
+
+  pub async fn commit_text(&mut self, line_text: &str) {
+    self.did_change(line_text).await;
+    self.document_text.push_str(&self.pending_text);
+    self.pending_text = String::new();
+  }
+
+  pub async fn completions(
+    &mut self,
+    line_text: &str,
+    position: usize,
+  ) -> Vec<ReplCompletionItem> {
+    self.did_change(line_text).await;
+    let before_line_len = BytePos(self.document_text.len() as u32);
+    let position = before_line_len + BytePos(position as u32);
+    let text_info = deno_ast::SourceTextInfo::from_string(format!(
+      "{}{}",
+      self.document_text, self.pending_text
+    ));
+    let line_and_column = text_info.line_and_column_index(position);
+    let response = self
+      .language_server
+      .completion(CompletionParams {
+        text_document_position: TextDocumentPositionParams {
+          text_document: TextDocumentIdentifier {
+            uri: self.get_document_specifier(),
+          },
+          position: Position {
+            line: line_and_column.line_index as u32,
+            character: line_and_column.column_index as u32,
+          },
+        },
+        work_done_progress_params: WorkDoneProgressParams {
+          work_done_token: None,
+        },
+        partial_result_params: PartialResultParams {
+          partial_result_token: None,
+        },
+        context: Some(CompletionContext {
+          trigger_kind: CompletionTriggerKind::INVOKED,
+          trigger_character: None,
+        }),
+      })
+      .await
+      .ok()
+      .unwrap_or_default();
+
+    let items = match response {
+      Some(CompletionResponse::Array(items)) => items,
+      Some(CompletionResponse::List(list)) => list.items,
+      None => Vec::new(),
+    };
+    items
+      .into_iter()
+      .filter_map(|item| {
+        item.text_edit.and_then(|edit| match edit {
+          CompletionTextEdit::Edit(edit) => Some(ReplCompletionItem {
+            new_text: edit.new_text,
+            span: lsp_range_to_span(&text_info, &edit.range),
+          }),
+          CompletionTextEdit::InsertAndReplace(_) => None,
+        })
+      })
+      .filter(|item| {
+        // filter the results to only exact matches
+        let text = &text_info.text_str()
+          [item.span.lo.0 as usize..item.span.hi.0 as usize];
+        item.new_text.starts_with(text)
+      })
+      .map(|mut item| {
+        // convert back to a line position
+        item.span = Span::new(
+          item.span.lo - before_line_len,
+          item.span.hi - before_line_len,
+          Default::default(),
+        );
+        item
+      })
+      .collect()
+  }
+
+  async fn did_change(&mut self, new_text: &str) {
+    self.check_cwd_change().await;
+    let new_text = if new_text.ends_with('\n') {
+      new_text.to_string()
+    } else {
+      format!("{}\n", new_text)
+    };
+    self.document_version += 1;
+    let current_line_count =
+      self.document_text.chars().filter(|c| *c == '\n').count() as u32;
+    let pending_line_count =
+      self.pending_text.chars().filter(|c| *c == '\n').count() as u32;
+    self
+      .language_server
+      .did_change(DidChangeTextDocumentParams {
+        text_document: VersionedTextDocumentIdentifier {
+          uri: self.get_document_specifier(),
+          version: self.document_version,
+        },
+        content_changes: vec![TextDocumentContentChangeEvent {
+          range: Some(Range {
+            start: Position::new(current_line_count, 0),
+            end: Position::new(current_line_count + pending_line_count, 0),
+          }),
+          range_length: None,
+          text: new_text.to_string(),
+        }],
+      })
+      .await;
+    self.pending_text = new_text;
+  }
+
+  async fn check_cwd_change(&mut self) {
+    // handle if the cwd changes, if the cwd is deleted in the case of
+    // get_cwd_uri() erroring, then keep using it as the base
+    let cwd_uri = get_cwd_uri().unwrap_or_else(|_| self.cwd_uri.clone());
+    if self.cwd_uri != cwd_uri {
+      self
+        .language_server
+        .did_close(DidCloseTextDocumentParams {
+          text_document: TextDocumentIdentifier {
+            uri: self.get_document_specifier(),
+          },
+        })
+        .await;
+      self.cwd_uri = cwd_uri;
+      self.document_version = 0;
+      self.open_current_document().await;
+    }
+  }
+
+  async fn open_current_document(&self) {
+    self
+      .language_server
+      .did_open(DidOpenTextDocumentParams {
+        text_document: TextDocumentItem {
+          uri: self.get_document_specifier(),
+          language_id: "typescript".to_string(),
+          version: self.document_version,
+          text: format!("{}{}", self.document_text, self.pending_text),
+        },
+      })
+      .await;
+  }
+
+  fn get_document_specifier(&self) -> ModuleSpecifier {
+    self.cwd_uri.join("$deno$repl.ts").unwrap()
+  }
+}
+
+fn lsp_range_to_span(text_info: &SourceTextInfo, range: &Range) -> Span {
+  Span::new(
+    text_info.byte_index(LineAndColumnIndex {
+      line_index: range.start.line as usize,
+      column_index: range.start.character as usize,
+    }),
+    text_info.byte_index(LineAndColumnIndex {
+      line_index: range.end.line as usize,
+      column_index: range.end.character as usize,
+    }),
+    Default::default(),
+  )
+}
+
+fn get_cwd_uri() -> Result<ModuleSpecifier, AnyError> {
+  let cwd = std::env::current_dir()?;
+  ModuleSpecifier::from_directory_path(&cwd)
+    .map_err(|_| anyhow!("Could not get URI from {}", cwd.display()))
+}
+
+pub fn get_repl_workspace_settings() -> WorkspaceSettings {
+  WorkspaceSettings {
+    enable: true,
+    config: None,
+    cache: None,
+    import_map: None,
+    code_lens: Default::default(),
+    internal_debug: false,
+    lint: false,
+    unstable: false,
+    suggest: CompletionSettings {
+      complete_function_calls: false,
+      names: false,
+      paths: false,
+      auto_imports: false,
+      imports: ImportCompletionSettings {
+        auto_discover: false,
+        hosts: HashMap::from([("https://deno.land".to_string(), true)]),
+      },
+    },
+  }
+}