[PATCH v2 1/2] user32/tests: Fix failing WM_PASTE tests for edit control on Win10+.

[Eric Pouech]

From: Eric Pouech

There are cases in Windows10+ where the WM_PASTE message doesn't paste
the content of the clipboard.

This appeared in testing:
- almost always just after (for a couple of milliseconds) setting new
  content into the clipboard and closing it.
- in some unrelated rare occasions (like once for 400 runs).

It looks like another (installed) process had opened the clipboard and
forbids the paste command.
As WM_PASTE doesn't return success/error status, workaround it by
wrapping the WM_PASTE command into a helper, and retry when the
clipboard's content hasn't been pasted.

Wine-bug: https://bugs.winehq.org/show_bug.cgi?id=53276

Signed-off-by: Eric Pouech 
---
 dlls/user32/tests/edit.c | 37 ++++++++++++++++++++++++-------------
 1 file changed, 24 insertions(+), 13 deletions(-)

diff --git a/dlls/user32/tests/edit.c b/dlls/user32/tests/edit.c
index 2afbbd5bea4..9e350043a46 100644
--- a/dlls/user32/tests/edit.c
+++ b/dlls/user32/tests/edit.c
@@ -3175,12 +3175,32 @@ static void test_EM_GETHANDLE(void)
     DestroyWindow(hEdit);
 }

+/* In Windows 10+, the WM_PASTE message isn't always successful.
+ * So retry in case of failures.
+ */
+#define check_paste(h, e) _check_paste(__LINE__, (h), (e))
+static void _check_paste(unsigned int line, HWND hedit, unsigned explen)
+{
+    /* only retry on windows platform */
+    int tries = strcmp(winetest_platform, "wine") ? 3 : 1;
+    int len = 0;
+
+    SendMessageA(hedit, WM_SETTEXT, 0, (LPARAM)"");
+    do
+    {
+        SendMessageA(hedit, WM_PASTE, 0, 0);
+        if ((len = SendMessageA(hedit, WM_GETTEXTLENGTH, 0, 0))) break;
+        Sleep(1);
+    } while (--tries > 0);
+    ok_(__FILE__, line)(len == explen, "Unexpected len %u in edit\n", len);
+}
+
 static void test_paste(void)
 {
     HWND hEdit, hMultilineEdit;
     HANDLE hmem, hmem_ret;
     char *buffer;
-    int r, len;
+    int r;
     static const char *str = "this is a simple text";
     static const char *str2 = "first line\r\nsecond line";

@@ -3205,10 +3225,7 @@ static void test_paste(void)
     ok(r == TRUE, "expected %d, got %d\n", TRUE, r);

/* Paste single line */
-    SendMessageA(hEdit, WM_SETTEXT, 0, (LPARAM)"");
-    r = SendMessageA(hEdit, WM_PASTE, 0, 0);
-    len = SendMessageA(hEdit, WM_GETTEXTLENGTH, 0, 0);
-    ok(strlen(str) == len, "got %d\n", len);
+    check_paste(hEdit, strlen(str));

/* Prepare clipboard data with multiline text */
     hmem = GlobalAlloc(GMEM_MOVEABLE, 255);
@@ -3228,16 +3245,10 @@ static void test_paste(void)
     ok(r == TRUE, "expected %d, got %d\n", TRUE, r);

/* Paste multiline text in singleline edit - should be cut */
-    SendMessageA(hEdit, WM_SETTEXT, 0, (LPARAM)"");
-    r = SendMessageA(hEdit, WM_PASTE, 0, 0);
-    len = SendMessageA(hEdit, WM_GETTEXTLENGTH, 0, 0);
-    ok(strlen("first line") == len, "got %d\n", len);
+    check_paste(hEdit, strlen("first line"));

/* Paste multiline text in multiline edit */
-    SendMessageA(hMultilineEdit, WM_SETTEXT, 0, (LPARAM)"");
-    r = SendMessageA(hMultilineEdit, WM_PASTE, 0, 0);
-    len = SendMessageA(hMultilineEdit, WM_GETTEXTLENGTH, 0, 0);
-    ok(strlen(str2) == len, "got %d\n", len);
+    check_paste(hMultilineEdit, strlen(str2));

/* Cleanup */
     DestroyWindow(hEdit);