[LLDB][GUI] Add required property to text fields

[OmarEmaraDev]

Summary

This patch adds a required property to text fields and their
derivatives. Additionally, the Process Name and PID fields in the attach
form were marked as required.

[clayborg]

Nice smaller changes!

lldb/source/Core/IOHandlerCursesGUI.cpp

1079

I would remove the default parameter to make sure everyone sets this correctly. It also will help avoid compilation issue if we ever add more parameters in the future as this can sometimes cause implicit conversion bugs.

1278–1279

Remove default argument value for "required" as mentioned above.

1290–1293

Remove default argument value for "required" as mentioned above.

1321–1323

Remove default argument value for "required" as mentioned above.

1875

Remove default argument value for "required" as mentioned above.

1883–1884

Remove default argument value for "need_to_exist" and "required" as mentioned above. Have everyone set them each time.

1892–1893

Remove default argument value for "need_to_exist" and "required" as mentioned above. Have everyone set them each time.

1900

Remove default argument value for "required" as mentioned above.

[OmarEmaraDev]

• Remove default arguments

lldb/source/Core/IOHandlerCursesGUI.cpp

 //===-- IOHandlerCursesGUI.cpp --------------------------------------------===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 
 #include "lldb/Core/IOHandlerCursesGUI.h"
 #include "lldb/Host/Config.h"
 
 #if LLDB_ENABLE_CURSES
 #if CURSES_HAVE_NCURSES_CURSES_H
 #include <ncurses/curses.h>
 #include <ncurses/panel.h>
 #else
 #include <curses.h>

 protected:
   bool m_is_visible = true;
 };
 
 typedef std::unique_ptr<FieldDelegate> FieldDelegateUP;
 
 class TextFieldDelegate : public FieldDelegate {
 public:
-  TextFieldDelegate(const char *label, const char *content)
-      : m_label(label), m_cursor_position(0), m_first_visibile_char(0) {
+  TextFieldDelegate(const char *label, const char *content, bool required)
+      : m_label(label), m_required(required), m_cursor_position(0),
+        m_first_visibile_char(0) {
     if (content)
       m_content = content;
   }
 
   // Text fields are drawn as titled boxes of a single line, with a possible
   // error messages at the end.
   //
   // __[Label]___________
case KEY_BACKSPACE:
       RemoveChar();
       return eKeyHandled;
     default:
       break;
     }
     return eKeyNotHandled;
   }
 
+  void FieldDelegateExitCallback() override {
+    if (!IsSpecified() && m_required)
+      SetError("This field is required!");
+  }
+
+  bool IsSpecified() { return !m_content.empty(); }
+
   bool HasError() { return !m_error.empty(); }
 
   void ClearError() { m_error.clear(); }
 
   const std::string &GetError() { return m_error; }
 
   void SetError(const char *error) { m_error = error; }
 
   const std::string &GetText() { return m_content; }
 
 protected:
   std::string m_label;
+  bool m_required;
   // The position of the top left corner character of the border.
   std::string m_content;
   // The cursor position in the content string itself. Can be in the range
   // [0, GetContentLength()].
   int m_cursor_position;
   // The index of the first visible character in the content.
   int m_first_visibile_char;
   // The width of the fields content that was last drawn. Width can change, so
   // this is used to determine if scrolling is needed dynamically.
   int m_last_drawn_content_width;
   // Optional error message. If empty, field is considered to have no error.
   std::string m_error;
 };
 
 class IntegerFieldDelegate : public TextFieldDelegate {
 public:
-  IntegerFieldDelegate(const char *label, int content)
-      : TextFieldDelegate(label, std::to_string(content).c_str()) {}
+  IntegerFieldDelegate(const char *label, int content, bool required)
+      : TextFieldDelegate(label, std::to_string(content).c_str(), required) {}
 
   // Only accept digits.
   bool IsAcceptableChar(int key) override { return isdigit(key); }
 
   // Returns the integer content of the field.
   int GetInteger() { return std::stoi(m_content); }
 };
 
 class FileFieldDelegate : public TextFieldDelegate {
 public:
-  FileFieldDelegate(const char *label, const char *content,
-                    bool need_to_exist = true)
-      : TextFieldDelegate(label, content), m_need_to_exist(need_to_exist) {}
+  FileFieldDelegate(const char *label, const char *content, bool need_to_exist,
+                    bool required)
+      : TextFieldDelegate(label, content, required),
+        m_need_to_exist(need_to_exist) {}
 
-  // Set appropriate error messages if the file doesn't exists or is, in fact, a
-  // directory.
   void FieldDelegateExitCallback() override {
+    TextFieldDelegate::FieldDelegateExitCallback();
+    if (!IsSpecified())
+      return;
+
     FileSpec file(GetPath());
     if (m_need_to_exist && !FileSystem::Instance().Exists(file)) {
       SetError("File doesn't exist!");
       return;
     }
     if (FileSystem::Instance().IsDirectory(file)) {
       SetError("Not a file!");
       return;
     }
   }
 
   // Returns the path of the file.
   const std::string &GetPath() { return m_content; }
 
 protected:
   bool m_need_to_exist;
 };
 
 class DirectoryFieldDelegate : public TextFieldDelegate {
 public:
   DirectoryFieldDelegate(const char *label, const char *content,
-                         bool need_to_exist = true)
-      : TextFieldDelegate(label, content), m_need_to_exist(need_to_exist) {}
+                         bool need_to_exist, bool required)
+      : TextFieldDelegate(label, content, required),
+        m_need_to_exist(need_to_exist) {}
 
-  // Set appropriate error messages if the directory doesn't exists or is, in
-  // fact, a file.
   void FieldDelegateExitCallback() override {
+    TextFieldDelegate::FieldDelegateExitCallback();
+    if (!IsSpecified())
+      return;
+
     FileSpec file(GetPath());
     if (m_need_to_exist && !FileSystem::Instance().Exists(file)) {
       SetError("Directory doesn't exist!");
       return;
     }
     if (!FileSystem::Instance().IsDirectory(file)) {
       SetError("Not a directory!");
       return;
public:
   void ClearError() { m_error.clear(); }
 
   const std::string &GetError() { return m_error; }
 
   void SetError(const char *error) { m_error = error; }
 
   // Factory methods to create and add fields of specific types.
 
-  TextFieldDelegate *AddTextField(const char *label, const char *content) {
-    TextFieldDelegate *delegate = new TextFieldDelegate(label, content);
+  TextFieldDelegate *AddTextField(const char *label, const char *content,
+                                  bool required) {
+    TextFieldDelegate *delegate =
+        new TextFieldDelegate(label, content, required);
     m_fields.push_back(FieldDelegateUP(delegate));
     return delegate;
   }
 
   FileFieldDelegate *AddFileField(const char *label, const char *content,
-                                  bool need_to_exist = true) {
+                                  bool need_to_exist, bool required) {
     FileFieldDelegate *delegate =
-        new FileFieldDelegate(label, content, need_to_exist);
+        new FileFieldDelegate(label, content, need_to_exist, required);
     m_fields.push_back(FieldDelegateUP(delegate));
     return delegate;
   }
 
   DirectoryFieldDelegate *AddDirectoryField(const char *label,
                                             const char *content,
-                                            bool need_to_exist = true) {
+                                            bool need_to_exist, bool required) {
     DirectoryFieldDelegate *delegate =
-        new DirectoryFieldDelegate(label, content, need_to_exist);
+        new DirectoryFieldDelegate(label, content, need_to_exist, required);
     m_fields.push_back(FieldDelegateUP(delegate));
     return delegate;
   }
 
-  IntegerFieldDelegate *AddIntegerField(const char *label, int content) {
-    IntegerFieldDelegate *delegate = new IntegerFieldDelegate(label, content);
+  IntegerFieldDelegate *AddIntegerField(const char *label, int content,
+                                        bool required) {
+    IntegerFieldDelegate *delegate =
+        new IntegerFieldDelegate(label, content, required);
     m_fields.push_back(FieldDelegateUP(delegate));
     return delegate;
   }
 
   BooleanFieldDelegate *AddBooleanField(const char *label, bool content) {
     BooleanFieldDelegate *delegate = new BooleanFieldDelegate(label, content);
     m_fields.push_back(FieldDelegateUP(delegate));
     return delegate;

 class ProcessAttachFormDelegate : public FormDelegate {
 public:
   ProcessAttachFormDelegate(Debugger &debugger, WindowSP main_window_sp)
       : m_debugger(debugger), m_main_window_sp(main_window_sp) {
     std::vector<std::string> types;
     types.push_back(std::string("Name"));
     types.push_back(std::string("PID"));
     m_type_field = AddChoicesField("Attach By", 2, types);
-    m_pid_field = AddIntegerField("PID", 0);
+    m_pid_field = AddIntegerField("PID", 0, true);
     m_name_field =
-        AddTextField("Process Name", GetDefaultProcessName().c_str());
+        AddTextField("Process Name", GetDefaultProcessName().c_str(), true);
     m_continue_field = AddBooleanField("Continue once attached.", false);
     m_wait_for_field = AddBooleanField("Wait for process to launch.", false);
     m_include_existing_field =
         AddBooleanField("Include existing processes.", false);
     m_show_advanced_field = AddBooleanField("Show advanced settings.", false);
     m_plugin_field =
         AddChoicesField("Plugin Name", 3, GetPossiblePluginNames());