From efae1ab68badef66505363505aecce7a7c3dbe6a Mon Sep 17 00:00:00 2001
From: Terence Noone <me@techtricity.net>
Date: Wed, 7 Dec 2022 19:48:22 -0500
Subject: file(MAKE_DIRECTORY): Provide a more descriptive error message

Previously, MAKE_DIRECTORY would print `problem creating directory: {}`,
which was very unhelpful for debugging.  Extend the message with the
OS error string.
---
 Source/cmFileCommand.cxx                           | 6 ++++--
 Tests/RunCMake/file/MAKE_DIRECTORY-fail-result.txt | 1 +
 Tests/RunCMake/file/MAKE_DIRECTORY-fail-stderr.txt | 9 +++++++++
 Tests/RunCMake/file/MAKE_DIRECTORY-fail.cmake      | 2 ++
 Tests/RunCMake/file/RunCMakeTest.cmake             | 2 ++
 5 files changed, 18 insertions(+), 2 deletions(-)
 create mode 100644 Tests/RunCMake/file/MAKE_DIRECTORY-fail-result.txt
 create mode 100644 Tests/RunCMake/file/MAKE_DIRECTORY-fail-stderr.txt
 create mode 100644 Tests/RunCMake/file/MAKE_DIRECTORY-fail.cmake

diff --git a/Source/cmFileCommand.cxx b/Source/cmFileCommand.cxx
index cdd0408..dfce033 100644
--- a/Source/cmFileCommand.cxx
+++ b/Source/cmFileCommand.cxx
@@ -845,8 +845,10 @@ bool HandleMakeDirectoryCommand(std::vector<std::string> const& args,
       cmSystemTools::SetFatalErrorOccurred();
       return false;
     }
-    if (!cmSystemTools::MakeDirectory(*cdir)) {
-      std::string error = "problem creating directory: " + *cdir;
+    cmsys::Status mkdirStatus = cmSystemTools::MakeDirectory(*cdir);
+    if (!mkdirStatus) {
+      std::string error = cmStrCat("failed to create directory:\n  ", *cdir,
+                                   "\nbecause: ", mkdirStatus.GetString());
       status.SetError(error);
       return false;
     }
diff --git a/Tests/RunCMake/file/MAKE_DIRECTORY-fail-result.txt b/Tests/RunCMake/file/MAKE_DIRECTORY-fail-result.txt
new file mode 100644
index 0000000..d00491f
--- /dev/null
+++ b/Tests/RunCMake/file/MAKE_DIRECTORY-fail-result.txt
@@ -0,0 +1 @@
+1
diff --git a/Tests/RunCMake/file/MAKE_DIRECTORY-fail-stderr.txt b/Tests/RunCMake/file/MAKE_DIRECTORY-fail-stderr.txt
new file mode 100644
index 0000000..95fccdf
--- /dev/null
+++ b/Tests/RunCMake/file/MAKE_DIRECTORY-fail-stderr.txt
@@ -0,0 +1,9 @@
+^CMake Error at [^
+]*/MAKE_DIRECTORY-fail.cmake:[0-9]+ \(file\):
+  file failed to create directory:
+
+    [^
+]*/Tests/RunCMake/file/MAKE_DIRECTORY-fail-build/file/directory
+
+  because: [^
+]+$
diff --git a/Tests/RunCMake/file/MAKE_DIRECTORY-fail.cmake b/Tests/RunCMake/file/MAKE_DIRECTORY-fail.cmake
new file mode 100644
index 0000000..57a68e5
--- /dev/null
+++ b/Tests/RunCMake/file/MAKE_DIRECTORY-fail.cmake
@@ -0,0 +1,2 @@
+file(WRITE "${CMAKE_CURRENT_BINARY_DIR}/file" "")
+file(MAKE_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}/file/directory")
diff --git a/Tests/RunCMake/file/RunCMakeTest.cmake b/Tests/RunCMake/file/RunCMakeTest.cmake
index 752f7a0..c75e062 100644
--- a/Tests/RunCMake/file/RunCMakeTest.cmake
+++ b/Tests/RunCMake/file/RunCMakeTest.cmake
@@ -61,6 +61,8 @@ run_cmake_script(COPY_FILE-arg-unknown)
 run_cmake_script(COPY_FILE-input-missing)
 run_cmake_script(COPY_FILE-output-missing)
 
+run_cmake_script(MAKE_DIRECTORY-fail)
+
 run_cmake_script(RENAME-file-replace)
 run_cmake_script(RENAME-file-to-file)
 run_cmake_script(RENAME-file-to-dir-capture)
-- 
cgit v0.12