Avoid adding a RecordFieldPat variant to the Pat enum

Author: geoffreycopin

crates/ra_assists/src/handlers/reorder_fields.rs

@@ -4,71 +4,79 @@ use itertools::Itertools;
 
 use hir::{Adt, ModuleDef, PathResolution, Semantics, Struct};
 use ra_ide_db::RootDatabase;
-use ra_syntax::ast::{Name, Pat};
 use ra_syntax::{
-    ast,
-    ast::{Path, RecordField, RecordLit, RecordPat},
-    AstNode,
+    algo, ast,
+    ast::{Name, Path, RecordLit, RecordPat},
+    AstNode, SyntaxKind, SyntaxNode,
 };
 
 use crate::{
     assist_ctx::{Assist, AssistCtx},
     AssistId,
 };
+use ra_syntax::ast::{Expr, NameRef};
 
 pub(crate) fn reorder_fields(ctx: AssistCtx) -> Option<Assist> {
-    reorder_struct(ctx.clone()).or_else(|| reorder_struct_pat(ctx))
+    reorder::<RecordLit>(ctx.clone()).or_else(|| reorder::<RecordPat>(ctx))
 }
 
-fn reorder_struct(ctx: AssistCtx) -> Option<Assist> {
-    let record: RecordLit = ctx.find_node_at_offset()?;
-    reorder(ctx, &record, &record.path()?, field_name)
-}
-
-fn field_name(r: &RecordField) -> String {
-    r.name_ref()
-        .map(|name| name.syntax().text().to_string())
-        .or_else(|| r.expr().map(|e| e.syntax().text().to_string()))
-        .unwrap_or_default()
-}
-
-fn reorder_struct_pat(ctx: AssistCtx) -> Option<Assist> {
-    let record: RecordPat = ctx.find_node_at_offset()?;
-    reorder(ctx, &record, &record.path()?, field_pat_name)
-}
+fn reorder<R: AstNode>(ctx: AssistCtx) -> Option<Assist> {
+    let record = ctx.find_node_at_offset::<R>()?;
+    let path = record.syntax().children().find_map(Path::cast)?;
 
-fn field_pat_name(field: &Pat) -> String {
-    field.syntax().children().find_map(Name::cast).map(|n| n.to_string()).unwrap_or_default()
-}
+    let ranks = compute_fields_ranks(&path, &ctx)?;
 
-fn reorder<R: AstNode, F: AstNode + Eq + Clone>(
-    ctx: AssistCtx,
-    record: &R,
-    path: &Path,
-    field_name: fn(&F) -> String,
-) -> Option<Assist> {
-    let ranks = compute_fields_ranks(path, &ctx)?;
-    let fields: Vec<F> = get_fields(record);
-    let sorted_fields: Vec<F> =
-        sort_by_rank(&fields, |f| *ranks.get(&field_name(f)).unwrap_or(&usize::max_value()));
+    let fields = get_fields(&record.syntax());
+    let sorted_fields = sorted_by_rank(&fields, |node| {
+        *ranks.get(&get_field_name(node)).unwrap_or(&usize::max_value())
+    });
 
     if sorted_fields == fields {
         return None;
     }
 
     ctx.add_assist(AssistId("reorder_fields"), "Reorder record fields", |edit| {
-        for (old, new) in fields.into_iter().zip(sorted_fields) {
-            edit.replace_ast(old, new);
+        for (old, new) in fields.iter().zip(&sorted_fields) {
+            algo::diff(old, new).into_text_edit(edit.text_edit_builder());
         }
         edit.target(record.syntax().text_range())
     })
 }
 
-fn get_fields<R: AstNode, F: AstNode>(record: &R) -> Vec<F> {
-    record.syntax().children().flat_map(|n1| n1.children()).filter_map(|n3| F::cast(n3)).collect()
+fn get_fields_kind(node: &SyntaxNode) -> Vec<SyntaxKind> {
+    use SyntaxKind::*;
+    match node.kind() {
+        RECORD_LIT => vec![RECORD_FIELD],
+        RECORD_PAT => vec![RECORD_FIELD_PAT, BIND_PAT],
+        _ => vec![],
+    }
+}
+
+fn get_field_name(node: &SyntaxNode) -> String {
+    use SyntaxKind::*;
+    match node.kind() {
+        RECORD_FIELD => {
+            if let Some(name) = node.children().find_map(NameRef::cast) {
+                return name.to_string();
+            }
+            node.children().find_map(Expr::cast).map(|expr| expr.to_string()).unwrap_or_default()
+        }
+        BIND_PAT | RECORD_FIELD_PAT => {
+            node.children().find_map(Name::cast).map(|n| n.to_string()).unwrap_or_default()
+        }
+        _ => String::new(),
+    }
+}
+
+fn get_fields(record: &SyntaxNode) -> Vec<SyntaxNode> {
+    let kinds = get_fields_kind(record);
+    record.children().flat_map(|n| n.children()).filter(|n| kinds.contains(&n.kind())).collect()
 }
 
-fn sort_by_rank<F: AstNode + Clone>(fields: &[F], get_rank: impl FnMut(&F) -> usize) -> Vec<F> {
+fn sorted_by_rank(
+    fields: &[SyntaxNode],
+    get_rank: impl Fn(&SyntaxNode) -> usize,
+) -> Vec<SyntaxNode> {
     fields.iter().cloned().sorted_by_key(get_rank).collect()
 }
 

crates/ra_hir_def/src/body/lower.rs

@@ -691,8 +691,6 @@ impl ExprCollector<'_> {
             }
             // FIXME: implement
             ast::Pat::BoxPat(_) | ast::Pat::RangePat(_) | ast::Pat::MacroPat(_) => Pat::Missing,
-            // FIXME: implement
-            ast::Pat::RecordFieldPat(_) => Pat::Missing,
         };
         let ptr = AstPtr::new(&pat);
         self.alloc_pat(pattern, Either::Left(ptr))

crates/ra_syntax/src/ast/generated/nodes.rs

@@ -3256,7 +3256,6 @@ pub enum Pat {
     RangePat(RangePat),
     LiteralPat(LiteralPat),
     MacroPat(MacroPat),
-    RecordFieldPat(RecordFieldPat),
 }
 impl From<OrPat> for Pat {
     fn from(node: OrPat) -> Pat { Pat::OrPat(node) }
@@ -3303,15 +3302,12 @@ impl From<LiteralPat> for Pat {
 impl From<MacroPat> for Pat {
     fn from(node: MacroPat) -> Pat { Pat::MacroPat(node) }
 }
-impl From<RecordFieldPat> for Pat {
-    fn from(node: RecordFieldPat) -> Pat { Pat::RecordFieldPat(node) }
-}
 impl AstNode for Pat {
     fn can_cast(kind: SyntaxKind) -> bool {
         match kind {
             OR_PAT | PAREN_PAT | REF_PAT | BOX_PAT | BIND_PAT | PLACEHOLDER_PAT | DOT_DOT_PAT
             | PATH_PAT | RECORD_PAT | TUPLE_STRUCT_PAT | TUPLE_PAT | SLICE_PAT | RANGE_PAT
-            | LITERAL_PAT | MACRO_PAT | RECORD_FIELD_PAT => true,
+            | LITERAL_PAT | MACRO_PAT => true,
             _ => false,
         }
     }
@@ -3332,7 +3328,6 @@ impl AstNode for Pat {
             RANGE_PAT => Pat::RangePat(RangePat { syntax }),
             LITERAL_PAT => Pat::LiteralPat(LiteralPat { syntax }),
             MACRO_PAT => Pat::MacroPat(MacroPat { syntax }),
-            RECORD_FIELD_PAT => Pat::RecordFieldPat(RecordFieldPat { syntax }),
             _ => return None,
         };
         Some(res)
@@ -3354,7 +3349,6 @@ impl AstNode for Pat {
             Pat::RangePat(it) => &it.syntax,
             Pat::LiteralPat(it) => &it.syntax,
             Pat::MacroPat(it) => &it.syntax,
-            Pat::RecordFieldPat(it) => &it.syntax,
         }
     }
 }

xtask/src/ast_src.rs

@@ -741,7 +741,6 @@ pub(crate) const AST_SRC: AstSrc = AstSrc {
             RangePat,
             LiteralPat,
             MacroPat,
-            RecordFieldPat,
         }
 
         enum RecordInnerPat {