Merge #3829

3829: Adds to SSR match for semantically equivalent call and method call r=matklad a=mikhail-m1

#3186 
maybe I've missed some corner cases, but it works in general

Co-authored-by: Mikhail Modin <mikhailm1@gmail.com>

crates/ra_ide/src/ssr.rs

@@ -5,12 +5,14 @@ use ra_db::{SourceDatabase, SourceDatabaseExt};
 use ra_ide_db::symbol_index::SymbolsDatabase;
 use ra_ide_db::RootDatabase;
 use ra_syntax::ast::make::try_expr_from_text;
-use ra_syntax::ast::{AstToken, Comment, RecordField, RecordLit};
-use ra_syntax::{AstNode, SyntaxElement, SyntaxNode};
+use ra_syntax::ast::{
+    ArgList, AstToken, CallExpr, Comment, Expr, MethodCallExpr, RecordField, RecordLit,
+};
+use ra_syntax::{AstNode, SyntaxElement, SyntaxKind, SyntaxNode};
 use ra_text_edit::{TextEdit, TextEditBuilder};
 use rustc_hash::FxHashMap;
 use std::collections::HashMap;
-use std::str::FromStr;
+use std::{iter::once, str::FromStr};
 
 #[derive(Debug, PartialEq)]
 pub struct SsrError(String);
@@ -219,6 +221,50 @@ fn find(pattern: &SsrPattern, code: &SyntaxNode) -> SsrMatches {
         )
     }
 
+    fn check_call_and_method_call(
+        pattern: CallExpr,
+        code: MethodCallExpr,
+        placeholders: &[Var],
+        match_: Match,
+    ) -> Option<Match> {
+        let (pattern_name, pattern_type_args) = if let Some(Expr::PathExpr(path_exr)) =
+            pattern.expr()
+        {
+            let segment = path_exr.path().and_then(|p| p.segment());
+            (segment.as_ref().and_then(|s| s.name_ref()), segment.and_then(|s| s.type_arg_list()))
+        } else {
+            (None, None)
+        };
+        let match_ = check_opt_nodes(pattern_name, code.name_ref(), placeholders, match_)?;
+        let match_ =
+            check_opt_nodes(pattern_type_args, code.type_arg_list(), placeholders, match_)?;
+        let pattern_args = pattern.syntax().children().find_map(ArgList::cast)?.args();
+        let code_args = code.syntax().children().find_map(ArgList::cast)?.args();
+        let code_args = once(code.expr()?).chain(code_args);
+        check_iter(pattern_args, code_args, placeholders, match_)
+    }
+
+    fn check_method_call_and_call(
+        pattern: MethodCallExpr,
+        code: CallExpr,
+        placeholders: &[Var],
+        match_: Match,
+    ) -> Option<Match> {
+        let (code_name, code_type_args) = if let Some(Expr::PathExpr(path_exr)) = code.expr() {
+            let segment = path_exr.path().and_then(|p| p.segment());
+            (segment.as_ref().and_then(|s| s.name_ref()), segment.and_then(|s| s.type_arg_list()))
+        } else {
+            (None, None)
+        };
+        let match_ = check_opt_nodes(pattern.name_ref(), code_name, placeholders, match_)?;
+        let match_ =
+            check_opt_nodes(pattern.type_arg_list(), code_type_args, placeholders, match_)?;
+        let code_args = code.syntax().children().find_map(ArgList::cast)?.args();
+        let pattern_args = pattern.syntax().children().find_map(ArgList::cast)?.args();
+        let pattern_args = once(pattern.expr()?).chain(pattern_args);
+        check_iter(pattern_args, code_args, placeholders, match_)
+    }
+
     fn check_opt_nodes(
         pattern: Option<impl AstNode>,
         code: Option<impl AstNode>,
@@ -227,8 +273,8 @@ fn find(pattern: &SsrPattern, code: &SyntaxNode) -> SsrMatches {
     ) -> Option<Match> {
         match (pattern, code) {
             (Some(pattern), Some(code)) => check(
-                &SyntaxElement::from(pattern.syntax().clone()),
-                &SyntaxElement::from(code.syntax().clone()),
+                &pattern.syntax().clone().into(),
+                &code.syntax().clone().into(),
                 placeholders,
                 match_,
             ),
@@ -237,6 +283,33 @@ fn find(pattern: &SsrPattern, code: &SyntaxNode) -> SsrMatches {
         }
     }
 
+    fn check_iter<T, I1, I2>(
+        mut pattern: I1,
+        mut code: I2,
+        placeholders: &[Var],
+        match_: Match,
+    ) -> Option<Match>
+    where
+        T: AstNode,
+        I1: Iterator<Item = T>,
+        I2: Iterator<Item = T>,
+    {
+        pattern
+            .by_ref()
+            .zip(code.by_ref())
+            .fold(Some(match_), |accum, (a, b)| {
+                accum.and_then(|match_| {
+                    check(
+                        &a.syntax().clone().into(),
+                        &b.syntax().clone().into(),
+                        placeholders,
+                        match_,
+                    )
+                })
+            })
+            .filter(|_| pattern.next().is_none() && code.next().is_none())
+    }
+
     fn check(
         pattern: &SyntaxElement,
         code: &SyntaxElement,
@@ -260,6 +333,14 @@ fn find(pattern: &SsrPattern, code: &SyntaxNode) -> SsrMatches {
                         (RecordLit::cast(pattern.clone()), RecordLit::cast(code.clone()))
                     {
                         check_record_lit(pattern, code, placeholders, match_)
+                    } else if let (Some(pattern), Some(code)) =
+                        (CallExpr::cast(pattern.clone()), MethodCallExpr::cast(code.clone()))
+                    {
+                        check_call_and_method_call(pattern, code, placeholders, match_)
+                    } else if let (Some(pattern), Some(code)) =
+                        (MethodCallExpr::cast(pattern.clone()), CallExpr::cast(code.clone()))
+                    {
+                        check_method_call_and_call(pattern, code, placeholders, match_)
                     } else {
                         let mut pattern_children = pattern
                             .children_with_tokens()
@@ -290,16 +371,15 @@ fn find(pattern: &SsrPattern, code: &SyntaxNode) -> SsrMatches {
     let kind = pattern.pattern.kind();
     let matches = code
         .descendants()
-        .filter(|n| n.kind() == kind)
+        .filter(|n| {
+            n.kind() == kind
+                || (kind == SyntaxKind::CALL_EXPR && n.kind() == SyntaxKind::METHOD_CALL_EXPR)
+                || (kind == SyntaxKind::METHOD_CALL_EXPR && n.kind() == SyntaxKind::CALL_EXPR)
+        })
         .filter_map(|code| {
             let match_ =
                 Match { place: code.clone(), binding: HashMap::new(), ignored_comments: vec![] };
-            check(
-                &SyntaxElement::from(pattern.pattern.clone()),
-                &SyntaxElement::from(code),
-                &pattern.vars,
-                match_,
-            )
+            check(&pattern.pattern.clone().into(), &code.into(), &pattern.vars, match_)
         })
         .collect();
     SsrMatches { matches }
@@ -498,4 +578,22 @@ mod tests {
             "fn main() { foo::new(1, 2) }",
         )
     }
+
+    #[test]
+    fn ssr_call_and_method_call() {
+        assert_ssr_transform(
+            "foo::<'a>($a:expr, $b:expr)) ==>> foo2($a, $b)",
+            "fn main() { get().bar.foo::<'a>(1); }",
+            "fn main() { foo2(get().bar, 1); }",
+        )
+    }
+
+    #[test]
+    fn ssr_method_call_and_call() {
+        assert_ssr_transform(
+            "$o:expr.foo::<i32>($a:expr)) ==>> $o.foo2($a)",
+            "fn main() { X::foo::<i32>(x, 1); }",
+            "fn main() { x.foo2(1); }",
+        )
+    }
 }