From 5fbf9b72f2294d85e358b5882b290310a9f7482b Mon Sep 17 00:00:00 2001
From: Teng Zhang <rahxephon89@163.com>
Date: Mon, 4 Nov 2024 19:37:38 +0000
Subject: [PATCH] [Compiler-v2][trivial] fix error handling for `match` in
 expansion phase (#15173)

* fix

* add error only when there isn't one
---
 .../tests/checking/variants/bug_15073.exp     |  7 +++++++
 .../tests/checking/variants/bug_15073.move    | 14 ++++++++++++++
 .../move-compiler/src/expansion/translate.rs  | 19 ++++++++++++++-----
 3 files changed, 35 insertions(+), 5 deletions(-)
 create mode 100644 third_party/move/move-compiler-v2/tests/checking/variants/bug_15073.exp
 create mode 100644 third_party/move/move-compiler-v2/tests/checking/variants/bug_15073.move

diff --git a/third_party/move/move-compiler-v2/tests/checking/variants/bug_15073.exp b/third_party/move/move-compiler-v2/tests/checking/variants/bug_15073.exp
new file mode 100644
index 0000000000000..7abba59d663f5
--- /dev/null
+++ b/third_party/move/move-compiler-v2/tests/checking/variants/bug_15073.exp
@@ -0,0 +1,7 @@
+
+Diagnostics:
+error: unbound module
+  ┌─ tests/checking/variants/bug_15073.move:8:13
+  │
+8 │             ToolType::Http { uri } => {
+  │             ^^^^^^^^ Unbound module or type alias 'ToolType'
diff --git a/third_party/move/move-compiler-v2/tests/checking/variants/bug_15073.move b/third_party/move/move-compiler-v2/tests/checking/variants/bug_15073.move
new file mode 100644
index 0000000000000..da326a52c95a8
--- /dev/null
+++ b/third_party/move/move-compiler-v2/tests/checking/variants/bug_15073.move
@@ -0,0 +1,14 @@
+module 0x815::m {
+
+    public fun init_registration(
+        creator: &signer,
+        tool_type: ToolType
+    ) {
+        match(tool_type) {
+            ToolType::Http { uri } => {
+
+            },
+        }
+
+    }
+}
diff --git a/third_party/move/move-compiler/src/expansion/translate.rs b/third_party/move/move-compiler/src/expansion/translate.rs
index ca954085198f3..b8ea685e454d7 100644
--- a/third_party/move/move-compiler/src/expansion/translate.rs
+++ b/third_party/move/move-compiler/src/expansion/translate.rs
@@ -2600,13 +2600,22 @@ fn exp_(context: &mut Context, sp!(loc, pe_): P::Exp) -> E::Exp {
             let discriminator = exp(context, *pd);
             let match_arms = parms
                 .into_iter()
-                .map(|parm| {
+                .filter_map(|parm| {
                     let loc = parm.loc;
                     let (pbl, pc, pb) = parm.value;
-                    let bind_list = bind_list(context, pbl).expect("bind list always present");
-                    let opt_cond = pc.map(|e| *exp(context, e));
-                    let body = *exp(context, pb);
-                    sp(loc, (bind_list, opt_cond, body))
+                    if let Some(bind_list) = bind_list(context, pbl) {
+                        let opt_cond = pc.map(|e| *exp(context, e));
+                        let body = *exp(context, pb);
+                        Some(sp(loc, (bind_list, opt_cond, body)))
+                    } else {
+                        if !context.env.has_errors() {
+                            context.env.add_diag(diag!(
+                                Syntax::InvalidLValue,
+                                (loc, "bind list cannot be constructed")
+                            ));
+                        }
+                        None
+                    }
                 })
                 .collect::<Vec<_>>();
             EE::Match(discriminator, match_arms)