Fix crash when array contents aren't an expression. (#3424)

FloatingPointLiteral wrap is a clang-format thing. I didn't touch it
manually.

toolchain/parse/node_kind.def

@@ -217,9 +217,9 @@ CARBON_PARSE_NODE_KIND_BRACKET(ImplicitParamList, ImplicitParamListStart,
 // ArrayExpr
 CARBON_PARSE_NODE_KIND_CHILD_COUNT(ArrayExprStart, 0,
                                    CARBON_TOKEN(OpenSquareBracket))
-CARBON_PARSE_NODE_KIND_CHILD_COUNT(
-    ArrayExprSemi, 2,
-    CARBON_TOKEN(Semi) CARBON_IF_ERROR(CARBON_TOKEN(CloseSquareBracket)))
+CARBON_PARSE_NODE_KIND_CHILD_COUNT(ArrayExprSemi, 2,
+                                   CARBON_TOKEN(Semi)
+                                       CARBON_IF_ERROR(CARBON_ANY_TOKEN))
 CARBON_PARSE_NODE_KIND_BRACKET(ArrayExpr, ArrayExprSemi,
                                CARBON_TOKEN(CloseSquareBracket))
 
@@ -429,7 +429,8 @@ CARBON_PARSE_NODE_KIND_TOKEN_LITERAL(BoolLiteralFalse, CARBON_TOKEN(False))
 CARBON_PARSE_NODE_KIND_TOKEN_LITERAL(BoolLiteralTrue, CARBON_TOKEN(True))
 CARBON_PARSE_NODE_KIND_TOKEN_LITERAL(IntegerLiteral,
                                      CARBON_TOKEN(IntegerLiteral))
-CARBON_PARSE_NODE_KIND_TOKEN_LITERAL(FloatingPointLiteral, CARBON_TOKEN(RealLiteral))
+CARBON_PARSE_NODE_KIND_TOKEN_LITERAL(FloatingPointLiteral,
+                                     CARBON_TOKEN(RealLiteral))
 CARBON_PARSE_NODE_KIND_TOKEN_LITERAL(StringLiteral, CARBON_TOKEN(StringLiteral))
 
 // A type literal.

toolchain/parse/testdata/array/fail_require_close_bracket.carbon

@@ -1,35 +0,0 @@
-// 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
-// TODO: It should emit only one error message.
-
-// CHECK:STDERR: fail_require_close_bracket.carbon:[[@LINE+9]]:8: ERROR: Closing symbol does not match most recent opening symbol.
-// CHECK:STDERR: var x: [i32;;
-// CHECK:STDERR:        ^
-// CHECK:STDERR: fail_require_close_bracket.carbon:[[@LINE+6]]:13: ERROR: Expected expression.
-// CHECK:STDERR: var x: [i32;;
-// CHECK:STDERR:             ^
-// CHECK:STDERR: fail_require_close_bracket.carbon:[[@LINE+3]]:13: ERROR: Unexpected tokens before `]`.
-// CHECK:STDERR: var x: [i32;;
-// CHECK:STDERR:             ^
-var x: [i32;;
-
-// CHECK:STDERR: fail_require_close_bracket.carbon:[[@LINE+16]]:21: ERROR: `var` declarations must end with a `;`.
-// CHECK:STDERR: // CHECK:STDOUT:   ]
-// CHECK:STDERR:                     ^
-// CHECK:STDOUT: - filename: fail_require_close_bracket.carbon
-// CHECK:STDOUT:   parse_tree: [
-// CHECK:STDOUT:     {kind: 'FileStart', text: ''},
-// CHECK:STDOUT:       {kind: 'VariableIntroducer', text: 'var'},
-// CHECK:STDOUT:         {kind: 'Name', text: 'x'},
-// CHECK:STDOUT:             {kind: 'ArrayExprStart', text: '['},
-// CHECK:STDOUT:             {kind: 'IntegerTypeLiteral', text: 'i32'},
-// CHECK:STDOUT:           {kind: 'ArrayExprSemi', text: ';', subtree_size: 3},
-// CHECK:STDOUT:           {kind: 'InvalidParse', text: ';', has_error: yes},
-// CHECK:STDOUT:         {kind: 'ArrayExpr', text: ']', has_error: yes, subtree_size: 5},
-// CHECK:STDOUT:       {kind: 'PatternBinding', text: ':', subtree_size: 7},
-// CHECK:STDOUT:     {kind: 'VariableDecl', text: 'var', has_error: yes, subtree_size: 9},
-// CHECK:STDOUT:     {kind: 'FileEnd', text: ''},
-// CHECK:STDOUT:   ]

toolchain/parse/testdata/array/fail_require_semi.carbon

@@ -1,24 +0,0 @@
-// 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
-
-// CHECK:STDERR: fail_require_semi.carbon:[[@LINE+3]]:12: ERROR: Expected `;` in array type.
-// CHECK:STDERR: var x: [i32];
-// CHECK:STDERR:            ^
-var x: [i32];
-
-// CHECK:STDOUT: - filename: fail_require_semi.carbon
-// CHECK:STDOUT:   parse_tree: [
-// CHECK:STDOUT:     {kind: 'FileStart', text: ''},
-// CHECK:STDOUT:       {kind: 'VariableIntroducer', text: 'var'},
-// CHECK:STDOUT:         {kind: 'Name', text: 'x'},
-// CHECK:STDOUT:             {kind: 'ArrayExprStart', text: '['},
-// CHECK:STDOUT:             {kind: 'IntegerTypeLiteral', text: 'i32'},
-// CHECK:STDOUT:           {kind: 'ArrayExprSemi', text: ']', has_error: yes, subtree_size: 3},
-// CHECK:STDOUT:         {kind: 'ArrayExpr', text: ']', has_error: yes, subtree_size: 4},
-// CHECK:STDOUT:       {kind: 'PatternBinding', text: ':', subtree_size: 6},
-// CHECK:STDOUT:     {kind: 'VariableDecl', text: ';', subtree_size: 8},
-// CHECK:STDOUT:     {kind: 'FileEnd', text: ''},
-// CHECK:STDOUT:   ]

toolchain/parse/testdata/array/fail_syntax.carbon

@@ -0,0 +1,141 @@
+// 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
+
+// --- type.carbon
+
+// CHECK:STDERR: type.carbon:[[@LINE+3]]:12: ERROR: Expected `;` in array type.
+// CHECK:STDERR: var x: [i32];
+// CHECK:STDERR:            ^
+var x: [i32];
+
+// --- invalid_char.carbon
+
+// CHECK:STDERR: invalid_char.carbon:[[@LINE+12]]:12: ERROR: Expected expression.
+// CHECK:STDERR: fn X() -> [:];
+// CHECK:STDERR:            ^
+// CHECK:STDERR: invalid_char.carbon:[[@LINE+9]]:12: ERROR: Expected `;` in array type.
+// CHECK:STDERR: fn X() -> [:];
+// CHECK:STDERR:            ^
+// CHECK:STDERR: invalid_char.carbon:[[@LINE+6]]:12: ERROR: Expected expression.
+// CHECK:STDERR: fn X() -> [:];
+// CHECK:STDERR:            ^
+// CHECK:STDERR: invalid_char.carbon:[[@LINE+3]]:12: ERROR: Unexpected tokens before `]`.
+// CHECK:STDERR: fn X() -> [:];
+// CHECK:STDERR:            ^
+fn X() -> [:];
+
+// --- unlexed_expr.carbon
+
+// CHECK:STDERR: unlexed_expr.carbon:[[@LINE+15]]:9: ERROR: Encountered unrecognized characters while parsing.
+// CHECK:STDERR: var y: [`];
+// CHECK:STDERR:         ^
+// CHECK:STDERR: unlexed_expr.carbon:[[@LINE+12]]:9: ERROR: Expected expression.
+// CHECK:STDERR: var y: [`];
+// CHECK:STDERR:         ^
+// CHECK:STDERR: unlexed_expr.carbon:[[@LINE+9]]:9: ERROR: Expected `;` in array type.
+// CHECK:STDERR: var y: [`];
+// CHECK:STDERR:         ^
+// CHECK:STDERR: unlexed_expr.carbon:[[@LINE+6]]:9: ERROR: Expected expression.
+// CHECK:STDERR: var y: [`];
+// CHECK:STDERR:         ^
+// CHECK:STDERR: unlexed_expr.carbon:[[@LINE+3]]:9: ERROR: Unexpected tokens before `]`.
+// CHECK:STDERR: var y: [`];
+// CHECK:STDERR:         ^
+var y: [`];
+
+// --- no_close_bracket.carbon
+
+// CHECK:STDERR: no_close_bracket.carbon:[[@LINE+9]]:8: ERROR: Closing symbol does not match most recent opening symbol.
+// CHECK:STDERR: var x: [i32;;
+// CHECK:STDERR:        ^
+// CHECK:STDERR: no_close_bracket.carbon:[[@LINE+6]]:13: ERROR: Expected expression.
+// CHECK:STDERR: var x: [i32;;
+// CHECK:STDERR:             ^
+// CHECK:STDERR: no_close_bracket.carbon:[[@LINE+3]]:13: ERROR: Unexpected tokens before `]`.
+// CHECK:STDERR: var x: [i32;;
+// CHECK:STDERR:             ^
+var x: [i32;;
+// CHECK:STDERR: no_close_bracket.carbon:[[@LINE+3]]:1: ERROR: `var` declarations must end with a `;`.
+// CHECK:STDERR:
+// CHECK:STDERR: ^
+
+// --- no_semi.carbon
+
+// CHECK:STDERR: no_semi.carbon:[[@LINE+3]]:12: ERROR: Expected `;` in array type.
+// CHECK:STDERR: var x: [i32];
+// CHECK:STDERR:            ^
+var x: [i32];
+
+// CHECK:STDOUT: - filename: type.carbon
+// CHECK:STDOUT:   parse_tree: [
+// CHECK:STDOUT:     {kind: 'FileStart', text: ''},
+// CHECK:STDOUT:       {kind: 'VariableIntroducer', text: 'var'},
+// CHECK:STDOUT:         {kind: 'Name', text: 'x'},
+// CHECK:STDOUT:             {kind: 'ArrayExprStart', text: '['},
+// CHECK:STDOUT:             {kind: 'IntegerTypeLiteral', text: 'i32'},
+// CHECK:STDOUT:           {kind: 'ArrayExprSemi', text: ']', has_error: yes, subtree_size: 3},
+// CHECK:STDOUT:         {kind: 'ArrayExpr', text: ']', has_error: yes, subtree_size: 4},
+// CHECK:STDOUT:       {kind: 'PatternBinding', text: ':', subtree_size: 6},
+// CHECK:STDOUT:     {kind: 'VariableDecl', text: ';', subtree_size: 8},
+// CHECK:STDOUT:     {kind: 'FileEnd', text: ''},
+// CHECK:STDOUT:   ]
+// CHECK:STDOUT: - filename: invalid_char.carbon
+// CHECK:STDOUT:   parse_tree: [
+// CHECK:STDOUT:     {kind: 'FileStart', text: ''},
+// CHECK:STDOUT:       {kind: 'FunctionIntroducer', text: 'fn'},
+// CHECK:STDOUT:       {kind: 'Name', text: 'X'},
+// CHECK:STDOUT:         {kind: 'ParamListStart', text: '('},
+// CHECK:STDOUT:       {kind: 'ParamList', text: ')', subtree_size: 2},
+// CHECK:STDOUT:             {kind: 'ArrayExprStart', text: '['},
+// CHECK:STDOUT:             {kind: 'InvalidParse', text: ':', has_error: yes},
+// CHECK:STDOUT:           {kind: 'ArrayExprSemi', text: ':', has_error: yes, subtree_size: 3},
+// CHECK:STDOUT:           {kind: 'InvalidParse', text: ':', has_error: yes},
+// CHECK:STDOUT:         {kind: 'ArrayExpr', text: ']', has_error: yes, subtree_size: 5},
+// CHECK:STDOUT:       {kind: 'ReturnType', text: '->', subtree_size: 6},
+// CHECK:STDOUT:     {kind: 'FunctionDecl', text: ';', subtree_size: 11},
+// CHECK:STDOUT:     {kind: 'FileEnd', text: ''},
+// CHECK:STDOUT:   ]
+// CHECK:STDOUT: - filename: unlexed_expr.carbon
+// CHECK:STDOUT:   parse_tree: [
+// CHECK:STDOUT:     {kind: 'FileStart', text: ''},
+// CHECK:STDOUT:       {kind: 'VariableIntroducer', text: 'var'},
+// CHECK:STDOUT:         {kind: 'Name', text: 'y'},
+// CHECK:STDOUT:             {kind: 'ArrayExprStart', text: '['},
+// CHECK:STDOUT:             {kind: 'InvalidParse', text: '`', has_error: yes},
+// CHECK:STDOUT:           {kind: 'ArrayExprSemi', text: '`', has_error: yes, subtree_size: 3},
+// CHECK:STDOUT:           {kind: 'InvalidParse', text: '`', has_error: yes},
+// CHECK:STDOUT:         {kind: 'ArrayExpr', text: ']', has_error: yes, subtree_size: 5},
+// CHECK:STDOUT:       {kind: 'PatternBinding', text: ':', subtree_size: 7},
+// CHECK:STDOUT:     {kind: 'VariableDecl', text: ';', subtree_size: 9},
+// CHECK:STDOUT:     {kind: 'FileEnd', text: ''},
+// CHECK:STDOUT:   ]
+// CHECK:STDOUT: - filename: no_close_bracket.carbon
+// CHECK:STDOUT:   parse_tree: [
+// CHECK:STDOUT:     {kind: 'FileStart', text: ''},
+// CHECK:STDOUT:       {kind: 'VariableIntroducer', text: 'var'},
+// CHECK:STDOUT:         {kind: 'Name', text: 'x'},
+// CHECK:STDOUT:             {kind: 'ArrayExprStart', text: '['},
+// CHECK:STDOUT:             {kind: 'IntegerTypeLiteral', text: 'i32'},
+// CHECK:STDOUT:           {kind: 'ArrayExprSemi', text: ';', subtree_size: 3},
+// CHECK:STDOUT:           {kind: 'InvalidParse', text: ';', has_error: yes},
+// CHECK:STDOUT:         {kind: 'ArrayExpr', text: ']', has_error: yes, subtree_size: 5},
+// CHECK:STDOUT:       {kind: 'PatternBinding', text: ':', subtree_size: 7},
+// CHECK:STDOUT:     {kind: 'VariableDecl', text: 'var', has_error: yes, subtree_size: 9},
+// CHECK:STDOUT:     {kind: 'FileEnd', text: ''},
+// CHECK:STDOUT:   ]
+// CHECK:STDOUT: - filename: no_semi.carbon
+// CHECK:STDOUT:   parse_tree: [
+// CHECK:STDOUT:     {kind: 'FileStart', text: ''},
+// CHECK:STDOUT:       {kind: 'VariableIntroducer', text: 'var'},
+// CHECK:STDOUT:         {kind: 'Name', text: 'x'},
+// CHECK:STDOUT:             {kind: 'ArrayExprStart', text: '['},
+// CHECK:STDOUT:             {kind: 'IntegerTypeLiteral', text: 'i32'},
+// CHECK:STDOUT:           {kind: 'ArrayExprSemi', text: ']', has_error: yes, subtree_size: 3},
+// CHECK:STDOUT:         {kind: 'ArrayExpr', text: ']', has_error: yes, subtree_size: 4},
+// CHECK:STDOUT:       {kind: 'PatternBinding', text: ':', subtree_size: 6},
+// CHECK:STDOUT:     {kind: 'VariableDecl', text: ';', subtree_size: 8},
+// CHECK:STDOUT:     {kind: 'FileEnd', text: ''},
+// CHECK:STDOUT:   ]