Fixes #429: now outputs a more informative error message when project folder has been moved and the build folder no longer contains a valid build

src/project.cpp

@@ -362,8 +362,12 @@ void Project::LLDB::debug_start() {
     auto view = Notebook::get().get_current_view();
     *run_arguments = build->get_executable(view ? view->file_path : Directories::get().path).string();
     if(run_arguments->empty()) {
-      Terminal::get().print("Warning: could not find executable.\n");
-      Terminal::get().print("Solution: either use Debug Set Run Arguments, or open a source file within a directory where an executable is defined.\n", true);
+      if(build->is_valid()) {
+        Terminal::get().print("Warning: could not find executable.\n");
+        Terminal::get().print("Solution: either use Project Set Run Arguments, or open a source file within a directory where an executable is defined.\n");
+      }
+      else
+        Terminal::get().print("Error: build folder no longer valid, please rebuild project.\n", true);
       return;
     }
     size_t pos = run_arguments->find(default_build_path.string());
@@ -870,8 +874,12 @@ void Project::Clang::compile_and_run() {
     auto view = Notebook::get().get_current_view();
     auto executable = build->get_executable(view ? view->file_path : Directories::get().path);
     if(executable.empty()) {
-      Terminal::get().print("Warning: could not find executable.\n");
-      Terminal::get().print("Solution: either use Project Set Run Arguments, or open a source file within a directory where an executable is defined.\n", true);
+      if(build->is_valid()) {
+        Terminal::get().print("Warning: could not find executable.\n");
+        Terminal::get().print("Solution: either use Project Set Run Arguments, or open a source file within a directory where an executable is defined.\n");
+      }
+      else
+        Terminal::get().print("Error: build folder no longer valid, please rebuild project.\n", true);
       return;
     }
     arguments = filesystem::escape_argument(filesystem::get_short_path(executable).string());

src/project_build.cpp

@@ -2,6 +2,8 @@
 #include "config.hpp"
 #include "filesystem.hpp"
 #include <boost/algorithm/string.hpp>
+#include <boost/property_tree/json_parser.hpp>
+#include <regex>
 
 std::unique_ptr<Project::Build> Project::Build::create(const boost::filesystem::path &path) {
   if(path.empty())
@@ -125,6 +127,25 @@ boost::filesystem::path Project::CMakeBuild::get_executable(const boost::filesys
   return executable;
 }
 
+bool Project::CMakeBuild::is_valid() {
+  if(project_path.empty())
+    return true;
+  auto default_path = get_default_path();
+  if(default_path.empty())
+    return true;
+  std::ifstream input((default_path / "CMakeCache.txt").string(), std::ofstream::binary);
+  if(!input)
+    return true;
+  std::string line;
+  while(std::getline(input, line)) {
+    const static std::regex regex("^.*_SOURCE_DIR:STATIC=(.*)$", std::regex::optimize);
+    std::smatch sm;
+    if(std::regex_match(line, sm, regex))
+      return boost::filesystem::path(sm[1].str()) == project_path;
+  }
+  return true;
+}
+
 std::vector<boost::filesystem::path> Project::CMakeBuild::get_exclude_paths() {
   auto exclude_paths = Project::Build::get_exclude_paths();
   exclude_paths.emplace_back(get_default_path());
@@ -160,6 +181,22 @@ boost::filesystem::path Project::MesonBuild::get_executable(const boost::filesys
   return executable;
 }
 
+bool Project::MesonBuild::is_valid() {
+  if(project_path.empty())
+    return true;
+  auto default_path = get_default_path();
+  if(default_path.empty())
+    return true;
+  boost::property_tree::ptree pt;
+  try {
+    boost::property_tree::json_parser::read_json((default_path / "meson-info" / "meson-info.json").string(), pt);
+    return boost::filesystem::path(pt.get<std::string>("directories.source")) == project_path;
+  }
+  catch(...) {
+  }
+  return true;
+}
+
 std::vector<boost::filesystem::path> Project::MesonBuild::get_exclude_paths() {
   auto exclude_paths = Project::Build::get_exclude_paths();
   exclude_paths.emplace_back(get_default_path());

src/project_build.hpp

@@ -18,6 +18,9 @@ namespace Project {
     virtual std::string get_compile_command() { return std::string(); }
     virtual boost::filesystem::path get_executable(const boost::filesystem::path &path) { return boost::filesystem::path(); }
 
+    /// Returns true if the project path reported by build system is correct
+    virtual bool is_valid() { return true; }
+
     virtual std::vector<boost::filesystem::path> get_exclude_paths();
 
     static std::unique_ptr<Build> create(const boost::filesystem::path &path);
@@ -35,6 +38,8 @@ namespace Project {
     std::string get_compile_command() override;
     boost::filesystem::path get_executable(const boost::filesystem::path &path) override;
 
+    bool is_valid() override;
+
     std::vector<boost::filesystem::path> get_exclude_paths() override;
   };
 
@@ -50,6 +55,8 @@ namespace Project {
     std::string get_compile_command() override;
     boost::filesystem::path get_executable(const boost::filesystem::path &path) override;
 
+    bool is_valid() override;
+
     std::vector<boost::filesystem::path> get_exclude_paths() override;
   };