[lldb] Simplify color logic in (IOHandler)Editline (NFC)

This patch simplifies the color handling logic in Editline and
IOHandlerEditline:

 - Remove the m_color_prompts property from Editline and use the prompt
   ANSI prefix and suffix as the single source of truth. This avoids
   having to redraw the prompt unnecessarily, for example when colors
   are enabled but the prompt prefix and suffix are empty.

 - Rename m_color_prompts to just m_color in IOHandlerEditline and use
   it to ensure consistency between colored prompts and colored
   auto-suggestions. Some IOHandler explicitly turn off colors (such as
   IOHandlerConfirm) and it doesn't really make sense to have one or the
   other.

Author: JDevlieghere

lldb/include/lldb/Core/IOHandler.h

@@ -328,7 +328,7 @@ class IOHandlerEditline : public IOHandler {
   IOHandlerEditline(Debugger &debugger, IOHandler::Type type,
                     const char *editline_name, // Used for saving history files
                     llvm::StringRef prompt, llvm::StringRef continuation_prompt,
-                    bool multi_line, bool color_prompts,
+                    bool multi_line, bool color,
                     uint32_t line_number_start, // If non-zero show line numbers
                                                 // starting at
                                                 // 'line_number_start'
@@ -340,7 +340,7 @@ class IOHandlerEditline : public IOHandler {
                     const lldb::StreamFileSP &error_sp, uint32_t flags,
                     const char *editline_name, // Used for saving history files
                     llvm::StringRef prompt, llvm::StringRef continuation_prompt,
-                    bool multi_line, bool color_prompts,
+                    bool multi_line, bool color,
                     uint32_t line_number_start, // If non-zero show line numbers
                                                 // starting at
                                                 // 'line_number_start'
@@ -432,7 +432,7 @@ class IOHandlerEditline : public IOHandler {
   uint32_t m_base_line_number; // If non-zero, then show line numbers in prompt
   uint32_t m_curr_line_idx;
   bool m_multi_line;
-  bool m_color_prompts;
+  bool m_color;
   bool m_interrupt_exits;
   std::string m_line_buffer;
 };

lldb/include/lldb/Host/Editline.h

@@ -153,8 +153,7 @@ using namespace line_editor;
 class Editline {
 public:
   Editline(const char *editor_name, FILE *input_file, FILE *output_file,
-           FILE *error_file, std::recursive_mutex &output_mutex,
-           bool color_prompts);
+           FILE *error_file, std::recursive_mutex &output_mutex);
 
   ~Editline();
 
@@ -371,7 +370,6 @@ class Editline {
   bool m_multiline_enabled = false;
   std::vector<EditLineStringType> m_input_lines;
   EditorStatus m_editor_status;
-  bool m_color_prompts = true;
   int m_terminal_width = 0;
   int m_base_line_number = 0;
   unsigned m_current_line_index = 0;

lldb/source/Core/IOHandler.cpp

@@ -226,15 +226,15 @@ IOHandlerEditline::IOHandlerEditline(
     Debugger &debugger, IOHandler::Type type,
     const char *editline_name, // Used for saving history files
     llvm::StringRef prompt, llvm::StringRef continuation_prompt,
-    bool multi_line, bool color_prompts, uint32_t line_number_start,
+    bool multi_line, bool color, uint32_t line_number_start,
     IOHandlerDelegate &delegate)
     : IOHandlerEditline(debugger, type,
                         FileSP(),       // Inherit input from top input reader
                         StreamFileSP(), // Inherit output from top input reader
                         StreamFileSP(), // Inherit error from top input reader
                         0,              // Flags
                         editline_name,  // Used for saving history files
-                        prompt, continuation_prompt, multi_line, color_prompts,
+                        prompt, continuation_prompt, multi_line, color,
                         line_number_start, delegate) {}
 
 IOHandlerEditline::IOHandlerEditline(
@@ -243,16 +243,16 @@ IOHandlerEditline::IOHandlerEditline(
     uint32_t flags,
     const char *editline_name, // Used for saving history files
     llvm::StringRef prompt, llvm::StringRef continuation_prompt,
-    bool multi_line, bool color_prompts, uint32_t line_number_start,
+    bool multi_line, bool color, uint32_t line_number_start,
     IOHandlerDelegate &delegate)
     : IOHandler(debugger, type, input_sp, output_sp, error_sp, flags),
 #if LLDB_ENABLE_LIBEDIT
       m_editline_up(),
 #endif
       m_delegate(delegate), m_prompt(), m_continuation_prompt(),
       m_current_lines_ptr(nullptr), m_base_line_number(line_number_start),
-      m_curr_line_idx(UINT32_MAX), m_multi_line(multi_line),
-      m_color_prompts(color_prompts), m_interrupt_exits(true) {
+      m_curr_line_idx(UINT32_MAX), m_multi_line(multi_line), m_color(color),
+      m_interrupt_exits(true) {
   SetPrompt(prompt);
 
 #if LLDB_ENABLE_LIBEDIT
@@ -262,9 +262,9 @@ IOHandlerEditline::IOHandlerEditline(
                  m_input_sp && m_input_sp->GetIsRealTerminal();
 
   if (use_editline) {
-    m_editline_up = std::make_unique<Editline>(
-        editline_name, GetInputFILE(), GetOutputFILE(), GetErrorFILE(),
-        GetOutputMutex(), m_color_prompts);
+    m_editline_up = std::make_unique<Editline>(editline_name, GetInputFILE(),
+                                               GetOutputFILE(), GetErrorFILE(),
+                                               GetOutputMutex());
     m_editline_up->SetIsInputCompleteCallback(
         [this](Editline *editline, StringList &lines) {
           return this->IsInputCompleteCallback(editline, lines);
@@ -278,10 +278,12 @@ IOHandlerEditline::IOHandlerEditline(
       m_editline_up->SetSuggestionCallback([this](llvm::StringRef line) {
         return this->SuggestionCallback(line);
       });
-      m_editline_up->SetSuggestionAnsiPrefix(ansi::FormatAnsiTerminalCodes(
-          debugger.GetAutosuggestionAnsiPrefix()));
-      m_editline_up->SetSuggestionAnsiSuffix(ansi::FormatAnsiTerminalCodes(
-          debugger.GetAutosuggestionAnsiSuffix()));
+      if (m_color) {
+        m_editline_up->SetSuggestionAnsiPrefix(ansi::FormatAnsiTerminalCodes(
+            debugger.GetAutosuggestionAnsiPrefix()));
+        m_editline_up->SetSuggestionAnsiSuffix(ansi::FormatAnsiTerminalCodes(
+            debugger.GetAutosuggestionAnsiSuffix()));
+      }
     }
     // See if the delegate supports fixing indentation
     const char *indent_chars = delegate.IOHandlerGetFixIndentationCharacters();
@@ -476,7 +478,7 @@ bool IOHandlerEditline::SetPrompt(llvm::StringRef prompt) {
 #if LLDB_ENABLE_LIBEDIT
   if (m_editline_up) {
     m_editline_up->SetPrompt(m_prompt.empty() ? nullptr : m_prompt.c_str());
-    if (m_debugger.GetUseColor()) {
+    if (m_color) {
       m_editline_up->SetPromptAnsiPrefix(
           ansi::FormatAnsiTerminalCodes(m_debugger.GetPromptAnsiPrefix()));
       m_editline_up->SetPromptAnsiSuffix(

lldb/source/Host/common/Editline.cpp

@@ -622,7 +622,7 @@ int Editline::GetCharacter(EditLineGetCharType *c) {
 }
 
 const char *Editline::Prompt() {
-  if (m_color_prompts)
+  if (!m_prompt_ansi_prefix.empty() || !m_prompt_ansi_suffix.empty())
     m_needs_prompt_repaint = true;
   return m_current_prompt.c_str();
 }
@@ -1084,13 +1084,9 @@ unsigned char Editline::TypedCharacter(int ch) {
   llvm::StringRef line(line_info->buffer,
                        line_info->lastchar - line_info->buffer);
 
-  const char *ansi_prefix =
-      m_color_prompts ? m_suggestion_ansi_prefix.c_str() : "";
-  const char *ansi_suffix =
-      m_color_prompts ? m_suggestion_ansi_suffix.c_str() : "";
-
   if (std::optional<std::string> to_add = m_suggestion_callback(line)) {
-    std::string to_add_color = ansi_prefix + to_add.value() + ansi_suffix;
+    std::string to_add_color =
+        m_suggestion_ansi_prefix + to_add.value() + m_suggestion_ansi_suffix;
     fputs(typed.c_str(), m_output_file);
     fputs(to_add_color.c_str(), m_output_file);
     size_t new_autosuggestion_size = line.size() + to_add->length();
@@ -1381,10 +1377,10 @@ Editline *Editline::InstanceFor(EditLine *editline) {
 
 Editline::Editline(const char *editline_name, FILE *input_file,
                    FILE *output_file, FILE *error_file,
-                   std::recursive_mutex &output_mutex, bool color_prompts)
-    : m_editor_status(EditorStatus::Complete), m_color_prompts(color_prompts),
-      m_input_file(input_file), m_output_file(output_file),
-      m_error_file(error_file), m_input_connection(fileno(input_file), false),
+                   std::recursive_mutex &output_mutex)
+    : m_editor_status(EditorStatus::Complete), m_input_file(input_file),
+      m_output_file(output_file), m_error_file(error_file),
+      m_input_connection(fileno(input_file), false),
       m_output_mutex(output_mutex) {
   // Get a shared history instance
   m_editor_name = (editline_name == nullptr) ? "lldb-tmp" : editline_name;

lldb/unittests/Editline/EditlineTest.cpp

@@ -118,7 +118,7 @@ EditlineAdapter::EditlineAdapter()
   // Create an Editline instance.
   _editline_sp.reset(new lldb_private::Editline(
       "gtest editor", *_el_secondary_file, *_el_secondary_file,
-      *_el_secondary_file, output_mutex, false));
+      *_el_secondary_file, output_mutex));
   _editline_sp->SetPrompt("> ");
 
   // Hookup our input complete callback.