From fad385c5aad5b375566914f021e7afc96a204403 Mon Sep 17 00:00:00 2001
From: Oscar Dowson <odow@users.noreply.github.com>
Date: Sun, 26 May 2024 14:11:10 +1200
Subject: [PATCH] Improve error for unsupported container syntax like x[A][B]
 (#3756)

---
 src/Containers/macro.jl |  8 +++++++-
 test/test_macros.jl     | 12 ++++++++++++
 2 files changed, 19 insertions(+), 1 deletion(-)

diff --git a/src/Containers/macro.jl b/src/Containers/macro.jl
index 7b2322b532b..b20c6a76743 100644
--- a/src/Containers/macro.jl
+++ b/src/Containers/macro.jl
@@ -170,7 +170,13 @@ function _parse_ref_sets(error_fn::Function, expr::Expr)
     # `:(t[i, j; k])` is a `:ref`, while `:(t[i; j])` is a `:typed_vcat`. In
     # both cases `:t` is the first argument.
     if Meta.isexpr(c, :typed_vcat) || Meta.isexpr(c, :ref)
-        popfirst!(c.args)
+        name = popfirst!(c.args)
+        if !(name isa Symbol)
+            error_fn(
+                "Unsupported syntax: the expression `$name` cannot be used " *
+                "as a name.",
+            )
+        end
     end
     if Meta.isexpr(c, :vcat) || Meta.isexpr(c, :typed_vcat)
         # An expression like `t[i; k]` or `[i; k]`. The filtering condition is
diff --git a/test/test_macros.jl b/test/test_macros.jl
index 2321b8deaf9..d1a7f8dd9e3 100644
--- a/test/test_macros.jl
+++ b/test/test_macros.jl
@@ -2395,4 +2395,16 @@ function test_force_nonlinear()
     return
 end
 
+function test_unsupported_name_syntax_multiple_ref()
+    model = Model()
+    @test_throws_parsetime(
+        ErrorException(
+            "In `@variable(model, (x[1:1])[1:2])`: Unsupported syntax: " *
+            "the expression `x[1:1]` cannot be used as a name.",
+        ),
+        @variable(model, x[1:1][1:2]),
+    )
+    return
+end
+
 end  # module