From eb5ac239889ea4a65bbc316aa6f51b06a34c2cab Mon Sep 17 00:00:00 2001
From: yuyi <yuyi98@163.com>
Date: Sun, 23 May 2021 22:59:57 +0800
Subject: [PATCH] checker: fix match expr with if expr (fix #10177 #10178)
 (#10179)

---
 vlib/v/checker/checker.v                      |  3 ++
 vlib/v/checker/tests/if_match_expr.out        |  7 +++
 vlib/v/gen/c/cgen.v                           |  1 +
 .../match_expr_with_if_or_match_expr_test.v   | 43 +++++++++++++++++++
 4 files changed, 54 insertions(+)
 create mode 100644 vlib/v/tests/match_expr_with_if_or_match_expr_test.v

diff --git a/vlib/v/checker/checker.v b/vlib/v/checker/checker.v
index 23246c6f97..f0fe606a3a 100644
--- a/vlib/v/checker/checker.v
+++ b/vlib/v/checker/checker.v
@@ -5326,6 +5326,9 @@ pub fn (mut c Checker) match_expr(mut node ast.MatchExpr) ast.Type {
 			mut stmt := branch.stmts[branch.stmts.len - 1]
 			match mut stmt {
 				ast.ExprStmt {
+					if node.is_expr {
+						c.expected_type = node.expected_type
+					}
 					expr_type := c.expr(stmt.expr)
 					if ret_type == ast.void_type {
 						ret_type = expr_type
diff --git a/vlib/v/checker/tests/if_match_expr.out b/vlib/v/checker/tests/if_match_expr.out
index 81c13a7f69..9c6597646b 100644
--- a/vlib/v/checker/tests/if_match_expr.out
+++ b/vlib/v/checker/tests/if_match_expr.out
@@ -40,3 +40,10 @@ vlib/v/checker/tests/if_match_expr.vv:23:3: error: `match` expression branch has
       |         ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    24 |         _ = match true {true {1} else {-1}} // OK
    25 |         match true {true {1} else {-1}} // result
+vlib/v/checker/tests/if_match_expr.vv:25:3: error: return type mismatch, it should be `int`
+   23 |         match true {true {} else {}} // statement not expression
+   24 |         _ = match true {true {1} else {-1}} // OK
+   25 |         match true {true {1} else {-1}} // result
+      |         ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+   26 |     }
+   27 | }
diff --git a/vlib/v/gen/c/cgen.v b/vlib/v/gen/c/cgen.v
index 762e03a98a..5921517bfa 100644
--- a/vlib/v/gen/c/cgen.v
+++ b/vlib/v/gen/c/cgen.v
@@ -1018,6 +1018,7 @@ fn (mut g Gen) stmts_with_tmp_var(stmts []ast.Stmt, tmp_var string) {
 				g.skip_stmt_pos = true
 				g.write('$tmp_var = ')
 				g.stmt(stmt)
+				g.writeln(';')
 			}
 		} else {
 			g.stmt(stmt)
diff --git a/vlib/v/tests/match_expr_with_if_or_match_expr_test.v b/vlib/v/tests/match_expr_with_if_or_match_expr_test.v
new file mode 100644
index 0000000000..891f198079
--- /dev/null
+++ b/vlib/v/tests/match_expr_with_if_or_match_expr_test.v
@@ -0,0 +1,43 @@
+fn foo1() int {
+	return match 1 {
+		1 {
+			if true {
+				1
+			} else {
+				2
+			}
+		}
+		else {
+			if true {
+				3
+			} else {
+				4
+			}
+		}
+	}
+}
+
+fn foo2() int {
+	return match 1 {
+		1 {
+			match true {
+				true { 1 }
+				false { 2 }
+			}
+		}
+		else {
+			match false {
+				true { 3 }
+				false { 4 }
+			}
+		}
+	}
+}
+
+fn test_match_expr_with_if_or_match_expr() {
+	println(foo1())
+	assert foo1() == 1
+
+	println(foo2())
+	assert foo2() == 1
+}