From fb88b79178cecd37f6738bfaa454cd51447ec7b6 Mon Sep 17 00:00:00 2001
From: Stephen Chung <schungx@live.com>
Date: Wed, 19 Apr 2023 23:17:54 +0800
Subject: [PATCH] Fix bug in parsing index chains.

---
 CHANGELOG.md    |  1 +
 src/parser.rs   | 10 ++++++++--
 tests/arrays.rs | 28 ++++++++++++++++++++++------
 3 files changed, 31 insertions(+), 8 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7ee71de3..eee62da7 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -11,6 +11,7 @@ Buf fixes
 
 * `is_shared` is a reserved keyword and is now handled properly (e.g. it cannot be the target of a function pointer).
 * Re-optimizing an AST via `optimize_ast` with constants now works correctly for closures. Previously the hidden `Share` nodes are not removed and causes variable-not-found errors during runtime if the constants are not available in the scope.
+* Expressions such as `(v[0].func()).prop` now parse correctly.
 
 New features
 ------------
diff --git a/src/parser.rs b/src/parser.rs
index a5ba7f1d..a34c851c 100644
--- a/src/parser.rs
+++ b/src/parser.rs
@@ -1728,6 +1728,9 @@ impl Engine {
     ) -> ParseResult<Expr> {
         let mut settings = settings;
 
+        // Break just in case `lhs` is `Expr::Dot` or `Expr::Index`
+        let mut parent_options = ASTFlags::BREAK;
+
         // Tail processing all possible postfix operators
         loop {
             let (tail_token, ..) = input.peek().expect(NEVER_ENDS);
@@ -1842,13 +1845,16 @@ impl Engine {
                     let rhs =
                         self.parse_primary(input, state, lib, settings.level_up()?, options)?;
 
-                    Self::make_dot_expr(state, expr, rhs, ASTFlags::empty(), op_flags, tail_pos)?
+                    Self::make_dot_expr(state, expr, rhs, parent_options, op_flags, tail_pos)?
                 }
                 // Unknown postfix operator
                 (expr, token) => {
                     unreachable!("unknown postfix operator '{}' for {:?}", token, expr)
                 }
-            }
+            };
+
+            // The chain is now extended
+            parent_options = ASTFlags::empty();
         }
 
         // Cache the hash key for namespace-qualified variables
diff --git a/tests/arrays.rs b/tests/arrays.rs
index 23d0f98f..d8b24f4f 100644
--- a/tests/arrays.rs
+++ b/tests/arrays.rs
@@ -203,6 +203,22 @@ fn test_arrays() -> Result<(), Box<EvalAltResult>> {
     Ok(())
 }
 
+#[cfg(not(feature = "no_float"))]
+#[cfg(not(feature = "no_object"))]
+#[test]
+fn test_array_chaining() -> Result<(), Box<EvalAltResult>> {
+    let engine = Engine::new();
+
+    assert!(engine.eval::<bool>(
+        "
+            let v = [ PI() ];
+            ( v[0].cos() ).sin() == v[0].cos().sin()
+        "
+    )?);
+
+    Ok(())
+}
+
 #[test]
 fn test_array_index_types() -> Result<(), Box<EvalAltResult>> {
     let engine = Engine::new();
@@ -508,9 +524,9 @@ fn test_arrays_map_reduce() -> Result<(), Box<EvalAltResult>> {
 
     engine.eval::<()>(
         "
-                let x = [1, 2, 3, 2, 1];
-                x.find(|v| v > 4)
-            ",
+            let x = [1, 2, 3, 2, 1];
+            x.find(|v| v > 4)
+        ",
     )?;
 
     assert_eq!(
@@ -525,9 +541,9 @@ fn test_arrays_map_reduce() -> Result<(), Box<EvalAltResult>> {
 
     engine.eval::<()>(
         "
-                let x = [#{alice: 1}, #{bob: 2}, #{clara: 3}];
-                x.find_map(|v| v.dave)
-            ",
+            let x = [#{alice: 1}, #{bob: 2}, #{clara: 3}];
+            x.find_map(|v| v.dave)
+        ",
     )?;
 
     Ok(())