Merge b75dbe8df3 into c18d7941ef

Problem:  Invalidated regions are flushed during startup while grid is
          still uninitialized. Resulting in blanking the grid to black,
          perceived as flickering.
Solution: Avoid flushing invalidated regions while the grid is
          uninitialized.

CMakeLists.txt

@@ -50,11 +50,6 @@ file(GLOB DOCFILES CONFIGURE_DEPENDS ${PROJECT_SOURCE_DIR}/runtime/doc/*.txt)
 set_directory_properties(PROPERTIES
   EP_PREFIX "${DEPS_BUILD_DIR}")
 
-find_program(CCACHE_PRG ccache)
-if(CCACHE_PRG)
-  set(CMAKE_C_COMPILER_LAUNCHER ${CMAKE_COMMAND} -E env CCACHE_SLOPPINESS=pch_defines,time_macros ${CCACHE_PRG})
-endif()
-
 if(NOT CI_BUILD)
   set(CMAKE_INSTALL_MESSAGE NEVER)
 endif()

cmake/Deps.cmake

@@ -23,6 +23,12 @@ if(POLICY CMP0092)
   list(APPEND DEPS_CMAKE_ARGS -D CMAKE_POLICY_DEFAULT_CMP0092=NEW)
 endif()
 
+find_program(CACHE_PRG NAMES ccache sccache)
+if(CACHE_PRG)
+  set(CMAKE_C_COMPILER_LAUNCHER ${CMAKE_COMMAND} -E env CCACHE_SLOPPINESS=pch_defines,time_macros ${CACHE_PRG})
+  list(APPEND DEPS_CMAKE_CACHE_ARGS -DCMAKE_C_COMPILER_LAUNCHER:STRING=${CMAKE_C_COMPILER_LAUNCHER})
+endif()
+
 # MAKE_PRG
 if(UNIX)
   find_program(MAKE_PRG NAMES gmake make)
@@ -58,7 +64,8 @@ function(get_externalproject_options name DEPS_IGNORE_SHA)
 
   set(EXTERNALPROJECT_OPTIONS
     DOWNLOAD_NO_PROGRESS TRUE
-    EXTERNALPROJECT_OPTIONS URL ${${name_allcaps}_URL})
+    EXTERNALPROJECT_OPTIONS URL ${${name_allcaps}_URL}
+    CMAKE_CACHE_ARGS ${DEPS_CMAKE_CACHE_ARGS})
 
   if(NOT ${DEPS_IGNORE_SHA})
     list(APPEND EXTERNALPROJECT_OPTIONS URL_HASH SHA256=${${name_allcaps}_SHA256})

src/nvim/tui/tui.c

@@ -108,6 +108,7 @@ struct TUIData {
   bool set_cursor_color_as_str;
   bool cursor_color_changed;
   bool is_starting;
+  bool got_line;
   FILE *screenshot;
   cursorentry_T cursor_shapes[SHAPE_IDX_COUNT];
   HlAttrs clear_attrs;
@@ -1436,6 +1437,12 @@ void tui_flush(TUIData *tui)
   }
 
   while (kv_size(tui->invalid_regions)) {
+    // We don't want to invalidate regions when the entire grid is still invalid.
+    // Doing so will result in unnecessarily blanking the grid which results in flickering.
+    if (!tui->got_line) {
+      kv_size(tui->invalid_regions) = 0;
+      break;
+    }
     Rect r = kv_pop(tui->invalid_regions);
     assert(r.bot <= grid->height && r.right <= grid->width);
 
@@ -1616,6 +1623,7 @@ void tui_raw_line(TUIData *tui, Integer g, Integer linerow, Integer startcol, In
                   Integer clearcol, Integer clearattr, LineFlags flags, const schar_T *chunk,
                   const sattr_T *attrs)
 {
+  tui->got_line = true;
   UGrid *grid = &tui->grid;
   for (Integer c = startcol; c < endcol; c++) {
     grid->cells[linerow][c].data = chunk[c - startcol];