From aaf507996669d7be2d78af4522e21568f2dd9abc Mon Sep 17 00:00:00 2001
From: reuben olinsky <reubeno@users.noreply.github.com>
Date: Mon, 25 Nov 2024 18:15:09 -0800
Subject: [PATCH] fix: correct parsing of parens in arithmetic command

---
 brush-parser/src/parser.rs                            | 8 ++++----
 brush-shell/tests/cases/compound_cmds/arithmetic.yaml | 5 +++++
 2 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/brush-parser/src/parser.rs b/brush-parser/src/parser.rs
index 74f79023..98a62eb9 100644
--- a/brush-parser/src/parser.rs
+++ b/brush-parser/src/parser.rs
@@ -269,7 +269,7 @@ peg::parser! {
 
         // N.B. The arithmetic command is a non-sh extension.
         // N.B. The arithmetic for clause command is a non-sh extension.
-        rule compound_command() -> ast::CompoundCommand =
+        pub(crate) rule compound_command() -> ast::CompoundCommand =
             non_posix_extensions_enabled() a:arithmetic_command() { ast::CompoundCommand::Arithmetic(a) } /
             b:brace_group() { ast::CompoundCommand::BraceGroup(b) } /
             s:subshell() { ast::CompoundCommand::Subshell(s) } /
@@ -281,16 +281,16 @@ peg::parser! {
             non_posix_extensions_enabled() c:arithmetic_for_clause() { ast::CompoundCommand::ArithmeticForClause(c) } /
             expected!("compound command")
 
-        rule arithmetic_command() -> ast::ArithmeticCommand =
+        pub(crate) rule arithmetic_command() -> ast::ArithmeticCommand =
             specific_operator("(") specific_operator("(") expr:arithmetic_expression() specific_operator(")") specific_operator(")") {
                 ast::ArithmeticCommand { expr }
             }
 
-        rule arithmetic_expression() -> ast::UnexpandedArithmeticExpr =
+        pub(crate) rule arithmetic_expression() -> ast::UnexpandedArithmeticExpr =
             raw_expr:$(arithmetic_expression_piece()*) { ast::UnexpandedArithmeticExpr { value: raw_expr } }
 
         rule arithmetic_expression_piece() =
-            specific_operator("(") arithmetic_expression_piece()* specific_operator(")") {} /
+            specific_operator("(") (!specific_operator(")") arithmetic_expression_piece())* specific_operator(")") {} /
             !arithmetic_end() [_] {}
 
         // TODO: evaluate arithmetic end; the semicolon is used in arithmetic for loops.
diff --git a/brush-shell/tests/cases/compound_cmds/arithmetic.yaml b/brush-shell/tests/cases/compound_cmds/arithmetic.yaml
index 80c01760..455fb7bf 100644
--- a/brush-shell/tests/cases/compound_cmds/arithmetic.yaml
+++ b/brush-shell/tests/cases/compound_cmds/arithmetic.yaml
@@ -9,3 +9,8 @@ cases:
     stdin: |
       (( (0) )) && echo "0"
       (( (1) )) && echo "1"
+
+  - name: "Arithmetic statements with parens and operators"
+    stdin: |
+      (( (0) == 0 )) && echo "0 == 0"
+      (( (1) != 0 )) && echo "1 != 0"