introduce CallInfo

crates/ra_analysis/src/call_info.rs

@@ -7,10 +7,21 @@ use ra_syntax::{
 use ra_editor::find_node_at_offset;
 use hir::FnSignatureInfo;
 
-use crate::{FilePosition, db::RootDatabase};
+use crate::{FilePosition, CallInfo, db::RootDatabase};
+
+pub(crate) fn call_info(db: &RootDatabase, position: FilePosition) -> Cancelable<Option<CallInfo>> {
+    let (sig_info, active_parameter) = ctry!(call_info_(db, position)?);
+    let res = CallInfo {
+        label: sig_info.label,
+        doc: sig_info.doc,
+        parameters: sig_info.params,
+        active_parameter,
+    };
+    Ok(Some(res))
+}
 
 /// Computes parameter information for the given call expression.
-pub(crate) fn call_info(
+fn call_info_(
     db: &RootDatabase,
     position: FilePosition,
 ) -> Cancelable<Option<(FnSignatureInfo, Option<usize>)>> {

crates/ra_analysis/src/lib.rs

@@ -273,6 +273,14 @@ impl<T> RangeInfo<T> {
     }
 }
 
+#[derive(Debug)]
+pub struct CallInfo {
+    pub label: String,
+    pub doc: Option<String>,
+    pub parameters: Vec<String>,
+    pub active_parameter: Option<usize>,
+}
+
 /// `AnalysisHost` stores the current state of the world.
 #[derive(Debug, Default)]
 pub struct AnalysisHost {
@@ -393,10 +401,7 @@ impl Analysis {
         hover::hover(&*self.db, position)
     }
     /// Computes parameter information for the given call expression.
-    pub fn call_info(
+    pub fn call_info(&self, position: FilePosition) -> Cancelable<Option<CallInfo>> {
-        &self,
-        position: FilePosition,
-    ) -> Cancelable<Option<(FnSignatureInfo, Option<usize>)>> {
         call_info::call_info(&*self.db, position)
     }
     /// Returns a `mod name;` declaration which created the current module.

crates/ra_lsp_server/src/main_loop/handlers.rs

@@ -475,36 +475,30 @@ pub fn handle_signature_help(
     params: req::TextDocumentPositionParams,
 ) -> Result<Option<req::SignatureHelp>> {
     let position = params.try_conv_with(&world)?;
-
+    if let Some(call_info) = world.analysis().call_info(position)? {
-    if let Some((descriptor, active_param)) = world.analysis().resolve_callable(position)? {
+        let parameters: Vec<ParameterInformation> = call_info
-        let parameters: Vec<ParameterInformation> = descriptor
+            .parameters
-            .params
+            .into_iter()
-            .iter()
             .map(|param| ParameterInformation {
                 label: ParameterLabel::Simple(param.clone()),
                 documentation: None,
             })
             .collect();
-
+        let documentation = call_info.doc.map(|value| {
-        let documentation = if let Some(doc) = descriptor.doc {
+            Documentation::MarkupContent(MarkupContent {
-            Some(Documentation::MarkupContent(MarkupContent {
                 kind: MarkupKind::Markdown,
-                value: doc,
+                value,
-            }))
+            })
-        } else {
+        });
-            None
-        };
-
         let sig_info = SignatureInformation {
-            label: descriptor.label,
+            label: call_info.label,
             documentation,
             parameters: Some(parameters),
         };
-
         Ok(Some(req::SignatureHelp {
             signatures: vec![sig_info],
             active_signature: Some(0),
-            active_parameter: active_param.map(|a| a as u64),
+            active_parameter: call_info.active_parameter.map(|it| it as u64),
         }))
     } else {
         Ok(None)