From b5b60755228e3b1489d5cd43622c08d0d8d77bc9 Mon Sep 17 00:00:00 2001
From: Asit Dhal <dhal.asitk@gmail.com>
Date: Fri, 12 Jun 2020 04:59:32 +0200
Subject: cmake: add dedicated error for -E compare_files invalid arguments

Return 2 when user provides invalid arguments

Fixes: #20815
---
 Help/manual/cmake.1.rst                                                | 3 ++-
 Source/cmcmd.cxx                                                       | 2 +-
 .../RunCMake/CommandLine/E_compare_files-invalid-arguments-result.txt  | 1 +
 .../RunCMake/CommandLine/E_compare_files-invalid-arguments-stderr.txt  | 1 +
 Tests/RunCMake/CommandLine/RunCMakeTest.cmake                          | 1 +
 5 files changed, 6 insertions(+), 2 deletions(-)
 create mode 100644 Tests/RunCMake/CommandLine/E_compare_files-invalid-arguments-result.txt
 create mode 100644 Tests/RunCMake/CommandLine/E_compare_files-invalid-arguments-stderr.txt

diff --git a/Help/manual/cmake.1.rst b/Help/manual/cmake.1.rst
index 9becfc6..e4c662e 100644
--- a/Help/manual/cmake.1.rst
+++ b/Help/manual/cmake.1.rst
@@ -566,7 +566,8 @@ Available commands are:
 
 ``compare_files [--ignore-eol] <file1> <file2>``
   Check if ``<file1>`` is same as ``<file2>``. If files are the same,
-  then returns ``0``, if not it returns ``1``.  The ``--ignore-eol`` option
+  then returns ``0``, if not it returns ``1``.  In case of invalid
+  arguments, it retruns 2. The ``--ignore-eol`` option
   implies line-wise comparison and ignores LF/CRLF differences.
 
 ``copy <file>... <destination>``
diff --git a/Source/cmcmd.cxx b/Source/cmcmd.cxx
index cbc8e8f..6882fdd 100644
--- a/Source/cmcmd.cxx
+++ b/Source/cmcmd.cxx
@@ -582,7 +582,7 @@ int cmcmd::ExecuteCMakeCommand(std::vector<std::string> const& args)
         filesDiffer = cmsys::SystemTools::TextFilesDiffer(args[3], args[4]);
       } else {
         ::CMakeCommandUsage(args[0].c_str());
-        return 1;
+        return 2;
       }
 
       if (filesDiffer) {
diff --git a/Tests/RunCMake/CommandLine/E_compare_files-invalid-arguments-result.txt b/Tests/RunCMake/CommandLine/E_compare_files-invalid-arguments-result.txt
new file mode 100644
index 0000000..0cfbf08
--- /dev/null
+++ b/Tests/RunCMake/CommandLine/E_compare_files-invalid-arguments-result.txt
@@ -0,0 +1 @@
+2
diff --git a/Tests/RunCMake/CommandLine/E_compare_files-invalid-arguments-stderr.txt b/Tests/RunCMake/CommandLine/E_compare_files-invalid-arguments-stderr.txt
new file mode 100644
index 0000000..8d98f9d
--- /dev/null
+++ b/Tests/RunCMake/CommandLine/E_compare_files-invalid-arguments-stderr.txt
@@ -0,0 +1 @@
+.*
diff --git a/Tests/RunCMake/CommandLine/RunCMakeTest.cmake b/Tests/RunCMake/CommandLine/RunCMakeTest.cmake
index 16fdeef..f291f15 100644
--- a/Tests/RunCMake/CommandLine/RunCMakeTest.cmake
+++ b/Tests/RunCMake/CommandLine/RunCMakeTest.cmake
@@ -22,6 +22,7 @@ run_cmake_command(E_compare_files-different-eol ${CMAKE_COMMAND} -E compare_file
 run_cmake_command(E_compare_files-ignore-eol-same ${CMAKE_COMMAND} -E compare_files --ignore-eol ${RunCMake_SOURCE_DIR}/compare_files/lf ${RunCMake_SOURCE_DIR}/compare_files/crlf)
 run_cmake_command(E_compare_files-ignore-eol-empty ${CMAKE_COMMAND} -E compare_files --ignore-eol ${RunCMake_SOURCE_DIR}/compare_files/empty1 ${RunCMake_SOURCE_DIR}/compare_files/empty2)
 run_cmake_command(E_compare_files-ignore-eol-nonexistent ${CMAKE_COMMAND} -E compare_files --ignore-eol nonexistent_a nonexistent_b)
+run_cmake_command(E_compare_files-invalid-arguments ${CMAKE_COMMAND} -E compare_files file1.txt file2.txt file3.txt)
 run_cmake_command(E_echo_append ${CMAKE_COMMAND} -E echo_append)
 run_cmake_command(E_rename-no-arg ${CMAKE_COMMAND} -E rename)
 run_cmake_command(E_server-arg ${CMAKE_COMMAND} -E server --extra-arg)
-- 
cgit v0.12