file(DOWNLOAD): Fill STATUS variable on hash mismatch (#15987)

Although we fail with an error on a hash mismatch, it is not a fatal
error so the script may continue processing.  If the download itself had
no error then report in the STATUS variable that the operation was not
successful due to the hash mismatch.

Suggested-by: Tobias Hieta <tobias@hieta.se>

Source/cmFileCommand.cxx

@@ -3300,6 +3300,15 @@ cmFileCommand::HandleDownloadCommand(std::vector<std::string> const& args)
         << "           status: [" << (int)res << ";\""
           << ::curl_easy_strerror(res) << "\"]" << std::endl
         ;
+
+      if(!statusVar.empty() && res == 0)
+        {
+        std::string status = "1;HASH mismatch: "
+          "expected: " + expectedHash +
+          " actual: " + actualHash;
+        this->Makefile->AddDefinition(statusVar, status.c_str());
+        }
+
       this->SetError(oss.str());
       return false;
       }

Tests/RunCMake/file/DOWNLOAD-hash-mismatch-result.txt

@@ -0,0 +1 @@
+1

Tests/RunCMake/file/DOWNLOAD-hash-mismatch-stderr.txt

@@ -0,0 +1,12 @@
+^CMake Error at DOWNLOAD-hash-mismatch.cmake:[0-9]+ \(file\):
+  file DOWNLOAD HASH mismatch
+
+    for file: \[.*/Tests/RunCMake/file/DOWNLOAD-hash-mismatch-build/hash-mismatch.txt\]
+      expected hash: \[0123456789abcdef0123456789abcdef01234567\]
+        actual hash: \[da39a3ee5e6b4b0d3255bfef95601890afd80709\]
+             status: \[0;"No error"\]
+
+Call Stack \(most recent call first\):
+  CMakeLists.txt:[0-9]+ \(include\)
++
+status='1;HASH mismatch: expected: 0123456789abcdef0123456789abcdef01234567 actual: da39a3ee5e6b4b0d3255bfef95601890afd80709'$

Tests/RunCMake/file/DOWNLOAD-hash-mismatch.cmake

@@ -0,0 +1,7 @@
+file(DOWNLOAD
+  "file://${CMAKE_CURRENT_SOURCE_DIR}/DOWNLOAD-hash-mismatch.txt"
+  ${CMAKE_CURRENT_BINARY_DIR}/hash-mismatch.txt
+  EXPECTED_HASH SHA1=0123456789abcdef0123456789abcdef01234567
+  STATUS status
+  )
+message("status='${status}'")

Tests/RunCMake/file/RunCMakeTest.cmake

@@ -1,5 +1,6 @@
 include(RunCMake)
 
+run_cmake(DOWNLOAD-hash-mismatch)
 run_cmake(INSTALL-DIRECTORY)
 run_cmake(INSTALL-MESSAGE-bad)
 run_cmake(FileOpenFailRead)