value if/loop follow-ups

compiler_tests.odin

@@ -2131,10 +2131,11 @@ yield_compiles_and_runs :: proc(t: ^testing.T) {
 	status := compiler_core.compile_package("examples/programs/yield", output)
 	testing.expect_value(t, status, 0)
 	state := run_executable(output)
-	// Value blocks (untyped/typed, defer-spill, reassignment) plus value if-statements
-	// (untyped/typed/reassign/else-if/defer) and value loops (a labeled `for` search
-	// yielding `?usize` on both the found and not-found paths, and a labeled `while`)
-	// together produce 42.
+	// Value blocks (untyped/typed, defer-spill, reassignment), value if-statements
+	// (untyped/typed/reassign/else-if/defer, a branch that `return`s instead of yielding,
+	// and an unwrap-`if` as a value source), `orelse`, and value loops (a labeled `for`
+	// search yielding `?usize` on the found/not-found paths, a labeled `while`, and an
+	// untyped loop that yields `none` before any concrete value) together produce 42.
 	testing.expect_value(t, state.exit_code, 42)
 }
 
@@ -2179,9 +2180,9 @@ yield_misuse_is_diagnosed :: proc(t: ^testing.T) {
 
 @(test)
 yield_control_flow_is_diagnosed :: proc(t: ^testing.T) {
-	// Value if/loop misuse (milestone 20.5): an `if` value without an `else`; a
-	// branch that does not end in `yield`; a value loop whose body lacks a trailing
-	// fall-through `yield`; and a `yield :label` with no matching value loop.
+	// Value if/loop misuse: an `if` value without an `else`; a branch that neither
+	// yields nor exits on every path (milestone 20.6); a value loop whose body lacks a
+	// trailing fall-through `yield`; and a `yield :label` with no matching value loop.
 	text := `main :: func() i32 {
 	noelse :: if (true) {
 		yield 1
@@ -2218,7 +2219,7 @@ yield_control_flow_is_diagnosed :: proc(t: ^testing.T) {
 	stray_label := false
 	for diagnostic in diagnostics.items {
 		no_else = no_else || strings.contains(diagnostic.message, "an 'if' used as a value must have an 'else'")
-		branch_no_yield = branch_no_yield || strings.contains(diagnostic.message, "a value block must end with an explicit 'yield'")
+		branch_no_yield = branch_no_yield || strings.contains(diagnostic.message, "a value branch must end with 'yield' or exit on every path")
 		loop_no_yield = loop_no_yield || strings.contains(diagnostic.message, "a value loop's body must end with a 'yield'")
 		stray_label = stray_label || strings.contains(diagnostic.message, "no enclosing value loop is labeled 'stray'")
 	}