From 6ae79eddb92fa55c4fee6249cf984f756efccb5d Mon Sep 17 00:00:00 2001
From: Yingchi Long <i@lyc.dev>
Date: Wed, 24 Jan 2024 13:26:20 +0800
Subject: [PATCH] fixup! libnixf: use sync tokens for creating unknown nodes
 (error recovery)

---
 libnixf/src/Parse/Parser.cpp | 27 +++++++++++++++------------
 1 file changed, 15 insertions(+), 12 deletions(-)

diff --git a/libnixf/src/Parse/Parser.cpp b/libnixf/src/Parse/Parser.cpp
index 1cc8f79ac..79e8a8df1 100644
--- a/libnixf/src/Parse/Parser.cpp
+++ b/libnixf/src/Parse/Parser.cpp
@@ -125,8 +125,7 @@ class Parser {
     Point Begin = peek().begin();
     bool Consumed = false;
     for (Token Tok = peek(); Tok.kind() != tok_eof; Tok = peek()) {
-      if (std::find(SyncTokens.begin(), SyncTokens.end(), Tok.kind()) !=
-          SyncTokens.end())
+      if (SyncTokens.contains(Tok.kind()))
         break;
       Consumed = true;
       consume();
@@ -160,7 +159,7 @@ class Parser {
     ExpectResult(Diagnostic *DiagMissing)
         : Success(false), DiagMissing(DiagMissing) {}
 
-    [[nodiscard]] bool success() const { return Success; }
+    [[nodiscard]] bool ok() const { return Success; }
     [[nodiscard]] Token tok() const {
       assert(Tok);
       return *Tok;
@@ -174,7 +173,6 @@ class Parser {
   ExpectResult expect(TokenKind Kind) {
     auto Sync = withSync(Kind);
     if (Token Tok = peek(); Tok.kind() == Kind) {
-      consume();
       return Tok;
     }
     // UNKNOWN ?
@@ -185,7 +183,6 @@ class Parser {
       D.fix("remove unexpected text").edit(TextEdit::mkRemoval(*UnknownRange));
 
       if (Token Tok = peek(); Tok.kind() == Kind) {
-        consume();
         return Tok;
       }
       // If the next token is not the expected one, then insert it.
@@ -233,10 +230,12 @@ class Parser {
       auto Expr = parseExpr();
       if (!Expr)
         diagNullExpr(Diags, LastToken->end(), "interpolation");
-      ExpectResult ER = expect(tok_r_curly); // }
-      if (!ER.success())
+      if (ExpectResult ER = expect(tok_r_curly); ER.ok()) {
+        consume(); // }
+      } else {
         ER.diag().note(Note::NK_ToMachThis, TokDollarCurly.range())
             << std::string(tok::spelling(tok_dollar_curly));
+      }
       return Expr;
     } // with(PS_Expr)
     return nullptr;
@@ -329,7 +328,8 @@ class Parser {
       auto StringState = withState(IsIndented ? PS_IndString : PS_String);
       std::shared_ptr<InterpolatedParts> Parts = parseStringParts();
       ExpectResult ER = expect(QuoteKind);
-      if (ER.success()) {
+      if (ER.ok()) {
+        consume();
         return std::make_shared<ExprString>(
             RangeTy{Quote.begin(), ER.tok().end()}, std::move(Parts));
       }
@@ -356,7 +356,8 @@ class Parser {
     if (!Expr)
       diagNullExpr(Diags, LastToken->end(), "parenthesized");
     ExpectResult ER = expect(tok_r_paren); // )
-    if (ER.success()) {
+    if (ER.ok()) {
+      consume();
       auto RParen = std::make_shared<Misc>(ER.tok().range());
       return std::make_shared<ExprParen>(RangeTy{L.begin(), ER.tok().end()},
                                          std::move(Expr), std::move(LParen),
@@ -434,7 +435,8 @@ class Parser {
     assert(LastToken && "LastToken should be set after valid attrpath");
     auto SyncEq = withSync(tok_eq);
     auto SyncSemi = withSync(tok_semi_colon);
-    expect(tok_eq);
+    if (ExpectResult ER = expect(tok_eq); ER.ok())
+      consume();
     auto Expr = parseExpr();
     if (!Expr)
       diagNullExpr(Diags, LastToken->end(), "binding");
@@ -504,8 +506,9 @@ class Parser {
     }
     assert(LastToken && "LastToken should be set after valid { or rec");
     auto Binds = parseBinds();
-    ExpectResult ER = expect(tok_r_curly);
-    if (!ER.success())
+    if (ExpectResult ER = expect(tok_r_curly); ER.ok())
+      consume();
+    else
       ER.diag().note(Note::NK_ToMachThis, Matcher.range())
           << std::string(tok::spelling(Matcher.kind()));
     return std::make_shared<ExprAttrs>(RangeTy{Begin, LastToken->end()},