From 81a7adc0e5115b3399fb4803572c7617ada07ee2 Mon Sep 17 00:00:00 2001
From: Jon Ross-Perkins <jperkins@google.com>
Date: Mon, 10 Apr 2023 15:54:43 -0700
Subject: [PATCH] Fix handling of invalid struct entries (#2755)

This was incorrectly setting the finish state back to unknown, which resulted in a check. Instead, the finish state should be maintained.
---
 toolchain/parser/parser.cpp                   |  3 +-
 .../struct/fail_mix_with_unknown.carbon       | 57 +++++++++++++++++++
 2 files changed, 58 insertions(+), 2 deletions(-)
 create mode 100644 toolchain/parser/testdata/struct/fail_mix_with_unknown.carbon

diff --git a/toolchain/parser/parser.cpp b/toolchain/parser/parser.cpp
index 2076fe26d919..7d52caa99bdb 100644
--- a/toolchain/parser/parser.cpp
+++ b/toolchain/parser/parser.cpp
@@ -600,8 +600,7 @@ auto Parser::HandleBraceExpressionParameterAfterDesignator(
   } else if (PositionIs(TokenKind::Equal)) {
     is_type = false;
   } else {
-    HandleBraceExpressionParameterError(
-        state, ParserState::BraceExpressionParameterFinishAsUnknown);
+    HandleBraceExpressionParameterError(state, param_finish_state);
     return;
   }
 
diff --git a/toolchain/parser/testdata/struct/fail_mix_with_unknown.carbon b/toolchain/parser/testdata/struct/fail_mix_with_unknown.carbon
new file mode 100644
index 000000000000..125d664f87a5
--- /dev/null
+++ b/toolchain/parser/testdata/struct/fail_mix_with_unknown.carbon
@@ -0,0 +1,57 @@
+// Part of the Carbon Language project, under the Apache License v2.0 with LLVM
+// Exceptions. See /LICENSE for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+// AUTOUPDATE
+// RUN: %{not} %{carbon-run-parser}
+// CHECK:STDOUT: [
+// CHECK:STDOUT:   {kind: 'VariableIntroducer', text: 'var'},
+// CHECK:STDOUT:     {kind: 'DeclaredName', text: 'x'},
+// CHECK:STDOUT:     {kind: 'Literal', text: 'i32'},
+// CHECK:STDOUT:   {kind: 'PatternBinding', text: ':', subtree_size: 3},
+// CHECK:STDOUT:   {kind: 'VariableInitializer', text: '='},
+// CHECK:STDOUT:     {kind: 'StructLiteralOrStructTypeLiteralStart', text: '{'},
+// CHECK:STDOUT:         {kind: 'DesignatedName', text: 'a'},
+// CHECK:STDOUT:       {kind: 'StructFieldDesignator', text: '.', subtree_size: 2},
+// CHECK:STDOUT:       {kind: 'Literal', text: '1'},
+// CHECK:STDOUT:     {kind: 'StructFieldValue', text: '=', subtree_size: 4},
+// CHECK:STDOUT:     {kind: 'StructComma', text: ','},
+// CHECK:STDOUT:       {kind: 'DesignatedName', text: 'b'},
+// CHECK:STDOUT:     {kind: 'StructFieldDesignator', text: '.', subtree_size: 2},
+// CHECK:STDOUT:     {kind: 'StructFieldUnknown', text: '.', has_error: yes},
+// CHECK:STDOUT:     {kind: 'StructComma', text: ','},
+// CHECK:STDOUT:       {kind: 'DesignatedName', text: 'c'},
+// CHECK:STDOUT:     {kind: 'StructFieldDesignator', text: '.', subtree_size: 2},
+// CHECK:STDOUT:     {kind: 'StructFieldUnknown', text: '.', has_error: yes},
+// CHECK:STDOUT:   {kind: 'StructLiteral', text: '}', subtree_size: 14},
+// CHECK:STDOUT: {kind: 'VariableDeclaration', text: ';', subtree_size: 20},
+// CHECK:STDOUT:   {kind: 'VariableIntroducer', text: 'var'},
+// CHECK:STDOUT:     {kind: 'DeclaredName', text: 'x'},
+// CHECK:STDOUT:     {kind: 'Literal', text: 'i32'},
+// CHECK:STDOUT:   {kind: 'PatternBinding', text: ':', subtree_size: 3},
+// CHECK:STDOUT:   {kind: 'VariableInitializer', text: '='},
+// CHECK:STDOUT:     {kind: 'StructLiteralOrStructTypeLiteralStart', text: '{'},
+// CHECK:STDOUT:         {kind: 'DesignatedName', text: 'a'},
+// CHECK:STDOUT:       {kind: 'StructFieldDesignator', text: '.', subtree_size: 2},
+// CHECK:STDOUT:       {kind: 'Literal', text: 'i32'},
+// CHECK:STDOUT:     {kind: 'StructFieldType', text: ':', subtree_size: 4},
+// CHECK:STDOUT:     {kind: 'StructComma', text: ','},
+// CHECK:STDOUT:       {kind: 'DesignatedName', text: 'b'},
+// CHECK:STDOUT:     {kind: 'StructFieldDesignator', text: '.', subtree_size: 2},
+// CHECK:STDOUT:     {kind: 'StructFieldUnknown', text: '.', has_error: yes},
+// CHECK:STDOUT:     {kind: 'StructComma', text: ','},
+// CHECK:STDOUT:       {kind: 'DesignatedName', text: 'c'},
+// CHECK:STDOUT:     {kind: 'StructFieldDesignator', text: '.', subtree_size: 2},
+// CHECK:STDOUT:     {kind: 'StructFieldUnknown', text: '.', has_error: yes},
+// CHECK:STDOUT:   {kind: 'StructTypeLiteral', text: '}', subtree_size: 14},
+// CHECK:STDOUT: {kind: 'VariableDeclaration', text: ';', subtree_size: 20},
+// CHECK:STDOUT: {kind: 'FileEnd', text: ''},
+// CHECK:STDOUT: ]
+
+// CHECK:STDERR: {{.*}}/toolchain/parser/testdata/struct/fail_mix_with_unknown.carbon:[[@LINE+2]]:25: Expected `.field = value`.
+// CHECK:STDERR: {{.*}}/toolchain/parser/testdata/struct/fail_mix_with_unknown.carbon:[[@LINE+1]]:29: Expected `.field = value`.
+var x: i32 = {.a = 1, .b, .c: i32};
+
+// CHECK:STDERR: {{.*}}/toolchain/parser/testdata/struct/fail_mix_with_unknown.carbon:[[@LINE+2]]:26: Expected `.field: field_type`.
+// CHECK:STDERR: {{.*}}/toolchain/parser/testdata/struct/fail_mix_with_unknown.carbon:[[@LINE+1]]:31: Expected `.field: field_type`.
+var x: i32 = {.a: i32, .b, .c = 1};