YAGNI active_resolve_capabilities

This leaks a lot of LSP details into ide layer, which we want to avoid:

https://github.com/rust-analyzer/rust-analyzer/tree/c9cec381bcfd97e5f3536e31a9c546ab5c0665e6/docs/dev#lsp-independence

Additionally, all what this infra does is providing a toggle for
auto-import completion, but we already have one!

3 files changed, 27 insertions, 47 deletions

diff --git a/crates/rust-analyzer/src/caps.rs b/crates/rust-analyzer/src/caps.rs
index 80e46bf7f15..3db0d55c5a8 100644
--- a/crates/rust-analyzer/src/caps.rs
+++ b/crates/rust-analyzer/src/caps.rs
@@ -1,7 +1,6 @@
 //! Advertizes the capabilities of the LSP Server.
 use std::env;
 
-use ide::CompletionResolveCapability;
 use lsp_types::{
     CallHierarchyServerCapability, ClientCapabilities, CodeActionKind, CodeActionOptions,
     CodeActionProviderCapability, CodeLensOptions, CompletionOptions,
@@ -14,7 +13,6 @@ use lsp_types::{
     WorkDoneProgressOptions, WorkspaceFileOperationsServerCapabilities,
     WorkspaceServerCapabilities,
 };
-use rustc_hash::FxHashSet;
 use serde_json::json;
 
 use crate::semantic_tokens;
@@ -118,37 +116,31 @@ pub fn server_capabilities(client_caps: &ClientCapabilities) -> ServerCapabiliti
 }
 
 fn completions_resolve_provider(client_caps: &ClientCapabilities) -> Option<bool> {
-    if enabled_completions_resolve_capabilities(client_caps)?.is_empty() {
+    if completion_item_edit_resolve(client_caps) {
+        Some(true)
+    } else {
         log::info!("No `additionalTextEdits` completion resolve capability was found in the client capabilities, autoimport completion is disabled");
         None
-    } else {
-        Some(true)
     }
 }
 
 /// Parses client capabilities and returns all completion resolve capabilities rust-analyzer supports.
-pub(crate) fn enabled_completions_resolve_capabilities(
-    caps: &ClientCapabilities,
-) -> Option<FxHashSet<CompletionResolveCapability>> {
-    Some(
-        caps.text_document
-            .as_ref()?
-            .completion
-            .as_ref()?
-            .completion_item
-            .as_ref()?
-            .resolve_support
-            .as_ref()?
-            .properties
-            .iter()
-            .filter_map(|cap_string| match cap_string.as_str() {
-                "additionalTextEdits" => Some(CompletionResolveCapability::AdditionalTextEdits),
-                "detail" => Some(CompletionResolveCapability::Detail),
-                "documentation" => Some(CompletionResolveCapability::Documentation),
-                _unsupported => None,
-            })
-            .collect(),
-    )
+pub(crate) fn completion_item_edit_resolve(caps: &ClientCapabilities) -> bool {
+    (|| {
+        Some(
+            caps.text_document
+                .as_ref()?
+                .completion
+                .as_ref()?
+                .completion_item
+                .as_ref()?
+                .resolve_support
+                .as_ref()?
+                .properties
+                .iter()
+                .any(|cap_string| cap_string.as_str() == "additionalTextEdits"),
+        )
+    })() == Some(true)
 }
 
 fn code_action_capabilities(client_caps: &ClientCapabilities) -> CodeActionProviderCapability {
diff --git a/crates/rust-analyzer/src/config.rs b/crates/rust-analyzer/src/config.rs
index 24e7936fc9e..ce952631569 100644
--- a/crates/rust-analyzer/src/config.rs
+++ b/crates/rust-analyzer/src/config.rs
@@ -20,7 +20,7 @@ use rustc_hash::FxHashSet;
 use serde::{de::DeserializeOwned, Deserialize};
 use vfs::AbsPathBuf;
 
-use crate::{caps::enabled_completions_resolve_capabilities, diagnostics::DiagnosticsMapConfig};
+use crate::{caps::completion_item_edit_resolve, diagnostics::DiagnosticsMapConfig};
 
 config_data! {
     struct ConfigData {
@@ -536,12 +536,11 @@ impl Config {
     pub fn completion(&self) -> CompletionConfig {
         let mut res = CompletionConfig::default();
         res.enable_postfix_completions = self.data.completion_postfix_enable;
-        res.enable_autoimport_completions = self.data.completion_autoimport_enable;
+        res.enable_autoimport_completions =
+            self.data.completion_autoimport_enable && completion_item_edit_resolve(&self.caps);
         res.add_call_parenthesis = self.data.completion_addCallParenthesis;
         res.add_call_argument_snippets = self.data.completion_addCallArgumentSnippets;
         res.merge = self.merge_behavior();
-        res.active_resolve_capabilities =
-            enabled_completions_resolve_capabilities(&self.caps).unwrap_or_default();
 
         res.allow_snippets(try_or!(
             self.caps
diff --git a/crates/rust-analyzer/src/handlers.rs b/crates/rust-analyzer/src/handlers.rs
index 33661325a4d..a7bf0ec6a82 100644
--- a/crates/rust-analyzer/src/handlers.rs
+++ b/crates/rust-analyzer/src/handlers.rs
@@ -9,9 +9,8 @@ use std::{
 };
 
 use ide::{
-    CompletionResolveCapability, FileId, FilePosition, FileRange, HoverAction, HoverGotoTypeData,
-    LineIndex, NavigationTarget, Query, RangeInfo, Runnable, RunnableKind, SearchScope,
-    SourceChange, SymbolKind, TextEdit,
+    FileId, FilePosition, FileRange, HoverAction, HoverGotoTypeData, LineIndex, NavigationTarget,
+    Query, RangeInfo, Runnable, RunnableKind, SearchScope, SourceChange, SymbolKind, TextEdit,
 };
 use itertools::Itertools;
 use lsp_server::ErrorCode;
@@ -634,10 +633,9 @@ pub(crate) fn handle_completion(
             let mut new_completion_items =
                 to_proto::completion_item(&line_index, line_endings, item.clone());
 
-            if completion_config.resolve_additional_edits_lazily() {
+            if completion_config.enable_autoimport_completions {
                 for new_item in &mut new_completion_items {
-                    let _ = fill_resolve_data(&mut new_item.data, &item, &text_document_position)
-                        .take();
+                    fill_resolve_data(&mut new_item.data, &item, &text_document_position);
                 }
             }
 
@@ -663,15 +661,6 @@ pub(crate) fn handle_completion_resolve(
         .into());
     }
 
-    // FIXME resolve the other capabilities also?
-    let completion_config = &snap.config.completion();
-    if !completion_config
-        .active_resolve_capabilities
-        .contains(&CompletionResolveCapability::AdditionalTextEdits)
-    {
-        return Ok(original_completion);
-    }
-
     let resolve_data = match original_completion
         .data
         .take()
@@ -690,7 +679,7 @@ pub(crate) fn handle_completion_resolve(
     let additional_edits = snap
         .analysis
         .resolve_completion_edits(
-            &completion_config,
+            &snap.config.completion(),
             FilePosition { file_id, offset },
             &resolve_data.full_import_path,
             resolve_data.imported_name,