1 files changed, 84 insertions, 0 deletions
diff --git a/v_windows/v/old/vlib/v/fmt/tests/shared_input.vv b/v_windows/v/old/vlib/v/fmt/tests/shared_input.vv
new file mode 100644
index 0000000..dccb34a
--- /dev/null
+++ b/v_windows/v/old/vlib/v/fmt/tests/shared_input.vv
@@ -0,0 +1,84 @@
+import sync
+import time
+
+struct St {
+mut:
+	a int
+}
+
+fn (shared x St) f(shared z St) {
+	for _ in 0 .. reads_per_thread {
+		rlock x { // other instances may read at the same time
+			time.sleep(time.millisecond)
+			assert x.a == 7 || x.a == 5
+		}
+	}
+	lock z {
+		z.a--
+	}
+}
+
+fn g() shared St {
+shared  x := St{a: 12 }
+		return   x
+}
+
+fn h() ?shared St {
+    return error('no value')
+}
+
+fn k() {
+  shared  x := g()
+  shared y := h() or {
+      shared f := St{}
+	  f
+	 }
+	 shared z := h() ?
+	 shared p := v
+	 v := rlock  z {  z.a }
+	 rlock x; lock y, z; rlock p {
+	  z.a = x.a + y.a
+	  }
+	 println(v)
+}
+
+const (
+	reads_per_thread = 30
+	read_threads     = 10
+	writes           = 5
+)
+
+fn test_shared_lock() {
+	// object with separate read/write lock
+shared x := &St {
+a: 5
+}
+	shared z :=
+&St{
+		a: read_threads
+      	}
+	for  _  in 0.. read_threads {
+		go x.f(shared z)
+	}
+  	for  i in 0..writes {
+ lock x { // wait for ongoing reads to finish, don't start new ones
+			 x.a = 17 // this value should never be read
+	time.sleep(50* time.millisecond)
+	x.a = if (i & 1) == 0 {
+7} else {5}
+	} // now new reads are possible again
+time.sleep(20*time.millisecond)
+	}
+	// wait until all read threads are finished
+for finished:=false;; {
+	mut rr := 0
+		  rlock z {
+  rr = z.a
+	  finished = z.a == 0
+}
+if finished {
+		break
+		     }
+			time.sleep(100*time.millisecond)
+			}
+}