ImStrv: rework toward ensuring End is always set to constant can be compile time calculated

imgui.cpp

@@ -1632,7 +1632,6 @@ const char* ImStristr(const char* haystack, const char* haystack_end, const char
 
 const char* ImStrstr(ImStrv haystack, ImStrv needle)
 {
-    IM_IMSTR_ENSURE_HAS_END(needle);
     const char un0 = (char)*needle.Begin;
     while ((!haystack.End && *haystack.Begin) || (haystack.End && haystack.Begin < haystack.End))
     {
@@ -2361,8 +2360,7 @@ bool ImGuiTextFilter::PassFilter(ImStrv text) const
     if (Filters.empty())
         return true;
 
-    IM_IMSTR_ENSURE_HAS_END(text);
+    if (text.Empty()) // FIXME-IMSTR
-    if (text.Empty())
         text.Begin = text.End = "";
 
     for (int i = 0; i != Filters.Size; i++)
@@ -3032,14 +3030,9 @@ void ImGui::RenderText(ImVec2 pos, ImStrv text, bool hide_text_after_hash)
     // Hide anything after a '##' string
     const char* text_display_end;
     if (hide_text_after_hash)
-    {
         text_display_end = FindRenderedTextEnd(text);
-    }
     else
-    {
-        IM_IMSTR_ENSURE_HAS_END(text);
         text_display_end = text.End;
-    }
 
     if (text.Begin != text_display_end)
     {
@@ -3053,7 +3046,6 @@ void ImGui::RenderTextWrapped(ImVec2 pos, ImStrv text, float wrap_width)
 {
     ImGuiContext& g = *GImGui;
     ImGuiWindow* window = g.CurrentWindow;
-    IM_IMSTR_ENSURE_HAS_END(text);
 
     if (text.Begin != text.End)
     {
@@ -3313,7 +3305,6 @@ ImGuiID ImGuiWindow::GetID(ImStrv str)
     ImGuiID id = ImHashStr(str, seed);
     ImGui::KeepAliveID(id);
     ImGuiContext& g = *GImGui;
-    IM_IMSTR_ENSURE_HAS_END(str);
     if (g.DebugHookIdInfo == id)
         ImGui::DebugHookIdInfo(id, ImGuiDataType_String, str.Begin, str.End);
     return id;
@@ -3344,8 +3335,7 @@ ImGuiID ImGuiWindow::GetID(int n)
 ImGuiID ImGuiWindow::GetIDNoKeepAlive(ImStrv str)
 {
     ImGuiID seed = IDStack.back();
-    IM_IMSTR_ENSURE_HAS_END(str);
+    ImGuiID id = ImHashStr(str, seed);
-    ImGuiID id = ImHashStr(str.Begin, str.End - str.Begin, seed);
     ImGuiContext& g = *GImGui;
     if (g.DebugHookIdInfo == id)
         ImGui::DebugHookIdInfo(id, ImGuiDataType_String, str.Begin, str.End);
@@ -5009,7 +4999,6 @@ ImVec2 ImGui::CalcTextSize(ImStrv text, bool hide_text_after_double_hash, float
 {
     ImGuiContext& g = *GImGui;
 
-    IM_IMSTR_ENSURE_HAS_END(text);
     if (hide_text_after_double_hash)
         text.End = FindRenderedTextEnd(text);      // Hide anything after a '##' string
 

imgui.h

@@ -269,8 +269,7 @@ struct ImVec4
 #endif
 };
 
-#define IM_IMSTR_LENGTH(s)          (s.Begin ? (s.End ? (size_t)(s.End - s.Begin) : strlen(s.Begin)) : 0)
+#define IM_IMSTR_LENGTH(s)          (size_t)(s.End - s.Begin)
-#define IM_IMSTR_ENSURE_HAS_END(s)  if (s.End == NULL) s.End = s.Begin + strlen(s.Begin)
 
 // String view class.
 #define IMGUI_HAS_IMSTR
@@ -279,10 +278,10 @@ struct ImStrv
     const char* Begin;
     const char* End;
     ImStrv()                            { Begin = End = NULL; }
-    ImStrv(const char* b) { Begin = b; End = NULL; }
+    ImStrv(const char* b)               { Begin = b; End = b ? b + strlen(b) : NULL; }
-    ImStrv(const char* b, const char* e) { Begin = b; End = e; }
+    ImStrv(const char* b, const char* e){ Begin = b; End = e ? e : b + strlen(b); }
     ImStrv(const char* b, size_t size)  { Begin = b; End = b + size; }
-    bool Empty() const { return Begin == NULL || Begin == End || Begin[0] == 0; }
+    bool Empty() const                  { return Begin == End || Begin[0] == 0; } // FIXME: Ambiguous
     // void EnsureHasEnd() { if (End == NULL) End = Begin + Length(); }
     // size_t Length() const
     // {
@@ -301,10 +300,10 @@ struct ImStrv
             return memcmp(Begin, other.Begin, len) == 0;
         return false;
     }
-    operator bool() const { return Begin != NULL; }
+    inline operator bool() const { return Begin != NULL; }
-    char operator[](int index) const { return Begin[index]; }
+    inline char operator[](int index) const { return Begin[index]; }
 #ifdef IM_IMSTR_CLASS_EXTRA
-    IM_IMSTR_CLASS_EXTRA     // Define additional constructors and implicit cast operators in imconfig.h to convert back and forth between your math types and ImStrv.
+    IM_IMSTR_CLASS_EXTRA     // Define additional constructors and implicit cast operators in imconfig.h to convert back and forth between your string types and ImStrv.
 #endif
 };
 

imgui_draw.cpp

@@ -1578,7 +1578,6 @@ void ImDrawList::AddText(const ImFont* font, float font_size, const ImVec2& pos,
     if ((col & IM_COL32_A_MASK) == 0)
         return;
 
-    IM_IMSTR_ENSURE_HAS_END(text);
     if (text.Empty())
         return;
 
@@ -3345,7 +3344,6 @@ const char* ImFont::CalcWordWrapPositionA(float scale, ImStrv text, float wrap_w
 
     // Cut words that cannot possibly fit within one line.
     // e.g.: "The tropical fish" with ~5 characters worth of width --> "The tr" "opical" "fish"
-    IM_IMSTR_ENSURE_HAS_END(text);
 
     float line_width = 0.0f;
     float word_width = 0.0f;
@@ -3431,8 +3429,6 @@ const char* ImFont::CalcWordWrapPositionA(float scale, ImStrv text, float wrap_w
 
 ImVec2 ImFont::CalcTextSizeA(float size, float max_width, float wrap_width, ImStrv text, const char** remaining) const
 {
-    IM_IMSTR_ENSURE_HAS_END(text);
-
     const float line_height = size;
     const float scale = size / FontSize;
 
@@ -3540,8 +3536,6 @@ void ImFont::RenderChar(ImDrawList* draw_list, float size, ImVec2 pos, ImU32 col
 // Note: as with every ImDrawList drawing function, this expects that the font atlas texture is bound.
 void ImFont::RenderText(ImDrawList* draw_list, float size, ImVec2 pos, ImU32 col, const ImVec4& clip_rect, ImStrv text, float wrap_width, bool cpu_fine_clip) const
 {
-    IM_IMSTR_ENSURE_HAS_END(text); // ImGui:: functions generally already provides a valid text_end, so this is merely to handle direct calls.
-
     // Align to be pixel perfect
     pos.x = IM_FLOOR(pos.x);
     pos.y = IM_FLOOR(pos.y);

imgui_widgets.cpp

@@ -155,8 +155,6 @@ void ImGui::TextEx(ImStrv text, ImGuiTextFlags flags)
         return;
     ImGuiContext& g = *GImGui;
 
-    IM_IMSTR_ENSURE_HAS_END(text);
-
     const ImVec2 text_pos(window->DC.CursorPos.x, window->DC.CursorPos.y + window->DC.CurrLineTextBaseOffset);
     const float wrap_pos_x = window->DC.TextWrapPos;
     const bool wrap_enabled = (wrap_pos_x >= 0.0f);
@@ -4360,7 +4358,6 @@ bool ImGui::InputTextEx(ImStrv label, ImStrv hint, char* buf, int buf_size, cons
             if (ImStrv clipboard = GetClipboardText())
             {
                 // Filter pasted buffer
-                IM_IMSTR_ENSURE_HAS_END(clipboard);
                 const int clipboard_len = (int)IM_IMSTR_LENGTH(clipboard);
                 ImWchar* clipboard_filtered = (ImWchar*)IM_ALLOC((clipboard_len + 1) * sizeof(ImWchar));
                 int clipboard_filtered_len = 0;
@@ -4570,7 +4567,6 @@ bool ImGui::InputTextEx(ImStrv label, ImStrv hint, char* buf, int buf_size, cons
     const char* buf_display_end = NULL; // We have specialized paths below for setting the length
     if (is_displaying_hint)
     {
-        IM_IMSTR_ENSURE_HAS_END(hint);
         buf_display = hint.Begin;
         buf_display_end = hint.End;
     }