From fd971faae28495ae65efc8de6a4aa68ad470e19d Mon Sep 17 00:00:00 2001
From: firewave <firewave@users.noreply.github.com>
Date: Thu, 15 Aug 2024 13:51:41 +0200
Subject: [PATCH] Path: throw from `getAbsolutePath()` if the given path does
 not exist

---
 lib/path.cpp      |  9 ++++++++-
 lib/path.h        |  7 +++++++
 test/testpath.cpp | 15 ++++++++++++++-
 3 files changed, 29 insertions(+), 2 deletions(-)

diff --git a/lib/path.cpp b/lib/path.cpp
index 073f1ab9dfb2..9430608d1da4 100644
--- a/lib/path.cpp
+++ b/lib/path.cpp
@@ -371,11 +371,12 @@ std::string Path::getAbsoluteFilePath(const std::string& filePath)
 #elif defined(__linux__) || defined(__sun) || defined(__hpux) || defined(__GNUC__) || defined(__CPPCHECK__)
     // simplify the path since any non-existent part has to exist even if discarded by ".."
     std::string spath = Path::simplifyPath(filePath);
-    // TODO: assert if path exists?
     char * absolute = realpath(spath.c_str(), nullptr);
     if (absolute)
         absolute_path = absolute;
     free(absolute);
+    if (!filePath.empty() && !spath.empty() && absolute_path.empty() && !exists(spath))
+        throw std::runtime_error("path '" + filePath + "' does not exist");
 #else
 #error Platform absolute path function needed
 #endif
@@ -419,6 +420,12 @@ bool Path::isDirectory(const std::string &path)
     return file_type(path) == S_IFDIR;
 }
 
+bool Path::exists(const std::string &path)
+{
+    const auto type = file_type(path);
+    return type == S_IFREG || type == S_IFDIR;
+}
+
 std::string Path::join(const std::string& path1, const std::string& path2) {
     if (path1.empty() || path2.empty())
         return path1 + path2;
diff --git a/lib/path.h b/lib/path.h
index f3dd870af709..fda36c01f85a 100644
--- a/lib/path.h
+++ b/lib/path.h
@@ -190,6 +190,13 @@ class CPPCHECKLIB Path {
      */
     static bool isDirectory(const std::string &path);
 
+    /**
+     * @brief Checks if a given path exists (i.e. is a file or directory)
+     * @param path Path to be checked
+     * @return true if given path exists
+     */
+    static bool exists(const std::string &path);
+
     /**
      * join 2 paths with '/' separators
      */
diff --git a/test/testpath.cpp b/test/testpath.cpp
index 69608af75433..70d00e3e4cb6 100644
--- a/test/testpath.cpp
+++ b/test/testpath.cpp
@@ -50,6 +50,7 @@ class TestPath : public TestFixture {
         TEST_CASE(is_header);
         TEST_CASE(simplifyPath);
         TEST_CASE(getAbsolutePath);
+        TEST_CASE(exists);
     }
 
     void removeQuotationMarks() const {
@@ -476,13 +477,25 @@ class TestPath : public TestFixture {
 
 #ifndef _WIN32
         // the underlying realpath() call only returns something if the path actually exists
-        ASSERT_EQUALS("", Path::getAbsoluteFilePath("testabspath2.txt"));
+        ASSERT_THROW_EQUALS_2(Path::getAbsoluteFilePath("testabspath2.txt"), std::runtime_error, "path 'testabspath2.txt' does not exist");
 #else
         ASSERT_EQUALS(Path::toNativeSeparators(Path::join(cwd, "testabspath2.txt")), Path::getAbsoluteFilePath("testabspath2.txt"));
 #endif
 
         // TODO: test with symlinks
     }
+
+    void exists() const {
+        ScopedFile file("testpath.txt", "", "testpath");
+        ScopedFile file2("testpath2.txt", "");
+        ASSERT_EQUALS(true, Path::exists("testpath"));
+        ASSERT_EQUALS(true, Path::exists("testpath/testpath.txt"));
+        ASSERT_EQUALS(true, Path::exists("testpath2.txt"));
+
+        ASSERT_EQUALS(false, Path::exists("testpath2"));
+        ASSERT_EQUALS(false, Path::exists("testpath/testpath2.txt"));
+        ASSERT_EQUALS(false, Path::exists("testpath.txt"));
+    }
 };
 
 REGISTER_TEST(TestPath)