From 336c2105cba68a43f77b57c9e89f40e0d5f9a61e Mon Sep 17 00:00:00 2001
From: odow <o.dowson@gmail.com>
Date: Fri, 30 Aug 2024 09:11:58 +1200
Subject: [PATCH] Fix macro issue in indicator constraints

---
 src/indicator.jl        |  7 +++++--
 test/test_constraint.jl | 11 +++++++++++
 2 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/src/indicator.jl b/src/indicator.jl
index 58dfaaba49b..1342898faf9 100644
--- a/src/indicator.jl
+++ b/src/indicator.jl
@@ -71,13 +71,16 @@ function parse_constraint_call(
         )
     end
     f, lhs_parse_code = _rewrite_expression(variable)
-    push!(rhs_parsecode.args, lhs_parse_code)
+    parsecode = quote
+        $rhs_parsecode
+        $lhs_parse_code
+    end
     build_call = if vectorized
         :(_build_indicator_constraint.($error_fn, $f, $rhs_build_call, $S))
     else
         :(_build_indicator_constraint($error_fn, $f, $rhs_build_call, $S))
     end
-    return rhs_parsecode, build_call
+    return parsecode, build_call
 end
 
 function constraint_string(
diff --git a/test/test_constraint.jl b/test/test_constraint.jl
index fa6dc9b04a7..2f183a36092 100644
--- a/test/test_constraint.jl
+++ b/test/test_constraint.jl
@@ -2107,4 +2107,15 @@ function test_real_hermitian_in_zeros()
     return
 end
 
+function test_issue_3812()
+    model = Model()
+    @variable(model, b, Bin)
+    @variable(model, x)
+    c = @constraint(model, b => {x in MOI.EqualTo(1.0)})
+    o = constraint_object(c)
+    @test o.func == [b, x]
+    @test o.set == MOI.Indicator{MOI.ACTIVATE_ON_ONE}(MOI.EqualTo(1.0))
+    return
+end
+
 end  # module