CPackDeb: Use `CPACK_PACKAGE_DESCRIPTION_FILE`

Also, handle per-component description nicely.

6 files changed, 140 insertions, 3 deletions

diff --git a/Tests/RunCMake/CMakeLists.txt b/Tests/RunCMake/CMakeLists.txt
index 8fd5234..13fbecf 100644
--- a/Tests/RunCMake/CMakeLists.txt
+++ b/Tests/RunCMake/CMakeLists.txt
@@ -510,6 +510,7 @@ set(cpack_tests
   DEB.TIMESTAMPS
   DEB.MD5SUMS
   DEB.DEB_PACKAGE_VERSION_BACK_COMPATIBILITY
+  DEB.DEB_DESCRIPTION
 
   RPM.CUSTOM_BINARY_SPEC_FILE
   RPM.CUSTOM_NAMES
diff --git a/Tests/RunCMake/CPack/RunCMakeTest.cmake b/Tests/RunCMake/CPack/RunCMakeTest.cmake
index 8e98961..b0b7a99 100644
--- a/Tests/RunCMake/CPack/RunCMakeTest.cmake
+++ b/Tests/RunCMake/CPack/RunCMakeTest.cmake
@@ -39,3 +39,10 @@ run_cpack_test_subtests(EXTERNAL "none;good;good_multi;bad_major;bad_minor;inval
 if(RunCMake_GENERATOR MATCHES "Visual Studio|Xcode")
   run_cpack_test(CPACK_INSTALL_CMAKE_CONFIGURATIONS "ZIP" false "MONOLITHIC")
 endif()
+run_cpack_test_subtests(
+  DEB_DESCRIPTION
+  "CPACK_DEBIAN_PACKAGE_DESCRIPTION;CPACK_PACKAGE_DESCRIPTION;CPACK_PACKAGE_DESCRIPTION_FILE"
+  "DEB.DEB_DESCRIPTION"
+  false
+  "MONOLITHIC;COMPONENT"
+)
diff --git a/Tests/RunCMake/CPack/tests/DEB_DESCRIPTION/ExpectedFiles.cmake b/Tests/RunCMake/CPack/tests/DEB_DESCRIPTION/ExpectedFiles.cmake
new file mode 100644
index 0000000..39f18a3
--- /dev/null
+++ b/Tests/RunCMake/CPack/tests/DEB_DESCRIPTION/ExpectedFiles.cmake
@@ -0,0 +1,16 @@
+set(EXPECTED_FILES_COUNT_MONOLITHIC "1")
+set(EXPECTED_FILES_COUNT_COMPONENT "2")
+set(EXPECTED_FILES_COUNT "${EXPECTED_FILES_COUNT_${PACKAGING_TYPE}}")
+
+if(PACKAGING_TYPE STREQUAL "COMPONENT")
+  set(EXPECTED_FILE_1 "deb_description-0.1.1-*-satu.deb")
+  set(EXPECTED_FILE_2 "deb_description-0.1.1-*-dua.deb")
+  set(EXPECTED_FILE_CONTENT_1_LIST "/satu;/satu/CMakeLists.txt")
+  set(EXPECTED_FILE_CONTENT_2_LIST "/dua;/dua/CMakeLists.txt")
+
+elseif(PACKAGING_TYPE STREQUAL "MONOLITHIC")
+  set(EXPECTED_FILE_CONTENT_1_LIST "/dua;/dua/CMakeLists.txt;/satu;/satu/CMakeLists.txt")
+
+endif()
+
+# kate: indent-width 2;
diff --git a/Tests/RunCMake/CPack/tests/DEB_DESCRIPTION/VerifyResult.cmake b/Tests/RunCMake/CPack/tests/DEB_DESCRIPTION/VerifyResult.cmake
new file mode 100644
index 0000000..e9ac13a
--- /dev/null
+++ b/Tests/RunCMake/CPack/tests/DEB_DESCRIPTION/VerifyResult.cmake
@@ -0,0 +1,65 @@
+function(checkPackageDescription FILE EXPECTED_DESCRIPTION)
+  getPackageInfo("${FILE}" "_file_info")
+  string(UUID uuid NAMESPACE 00000000-0000-0000-0000-000000000000 TYPE SHA1)
+  string(REPLACE ";" "${uuid}" _file_info "${_file_info}")
+  string(REPLACE ";" "${uuid}" EXPECTED_DESCRIPTION "${EXPECTED_DESCRIPTION}")
+  string(REPLACE "\n" ";" _file_info "${_file_info}")
+
+  set(_actual_description)
+  set(_parse_description FALSE)
+  foreach(_line IN LISTS _file_info)
+    if(_line MATCHES " Description:.*")
+      set(_parse_description TRUE)
+      list(APPEND _actual_description "${_line}")
+    elseif(_parse_description)
+      if(_line MATCHES " [A-Z][A-Za-z\-]+: .*")
+        set(_parse_description FALSE)
+      else()
+        list(APPEND _actual_description "${_line}")
+      endif()
+    endif()
+  endforeach()
+  list(JOIN _actual_description "\n" _actual_description)
+
+  if(NOT _actual_description STREQUAL EXPECTED_DESCRIPTION)
+    set(_error "---[BEGIN Expected description]---\n${EXPECTED_DESCRIPTION}---[END Expected description]---\n")
+    string(APPEND _error "---[BEGIN Actual description]---\n${_actual_description}---[END Actual description]---\n")
+    string(REPLACE "${uuid}"  ";" _error "${_error}")
+    message(FATAL_ERROR "${_error}")
+  endif()
+endfunction()
+
+# ALERT The output of `dpkg -I *.deb` indented by one space
+set(_expected_description [[ Description: This is the summary line
+  This is the Debian package multiline description.
+  .
+  It must be formatted properly! Otherwise, the result `*.deb`
+  package become broken and cant be installed!
+  .
+  It may contains `;` characters (even like this `;;;;`). Example:
+  .
+    - one;
+    - two;
+    - three;
+  .
+  ... and they are properly handled by the automatic description formatter!
+  .
+  See also: https://www.debian.org/doc/debian-policy/ch-controlfields.html#description]])
+
+# ATTENTION The code in `cmCPackGenerator.cxx` to read `CPACK_PACKAGE_DESCRIPTION_FILE`
+# has a BUG: it appends the `\n` character to every line of the
+# input, even if there was no EOL (e.g. at the last line of the file).
+# That is WHY for this sub-test the one more pre-formatted "empty"
+# line required!
+# NOTE For component based installers content of the file gonna read by
+# `CPackDeb` module and the `file(READ...)` command so no the mentioned
+# workaround required!
+if(RunCMake_SUBTEST_SUFFIX STREQUAL "CPACK_PACKAGE_DESCRIPTION_FILE" AND PACKAGING_TYPE STREQUAL "MONOLITHIC")
+  string(APPEND _expected_description "\n  ." )
+endif()
+
+foreach(_file_no RANGE 1 ${EXPECTED_FILES_COUNT})
+  checkPackageDescription("${FOUND_FILE_${_file_no}}" "${_expected_description}")
+endforeach()
+
+# kate: indent-width 2;
diff --git a/Tests/RunCMake/CPack/tests/DEB_DESCRIPTION/test.cmake b/Tests/RunCMake/CPack/tests/DEB_DESCRIPTION/test.cmake
new file mode 100644
index 0000000..ce3f651
--- /dev/null
+++ b/Tests/RunCMake/CPack/tests/DEB_DESCRIPTION/test.cmake
@@ -0,0 +1,45 @@
+install(FILES CMakeLists.txt DESTINATION satu COMPONENT satu)
+install(FILES CMakeLists.txt DESTINATION dua COMPONENT dua)
+
+set(CPACK_PACKAGE_DESCRIPTION_SUMMARY "This is the summary line")
+set(_description [[This is the Debian package multiline description.
+
+It must be formatted properly! Otherwise, the result `*.deb`
+package become broken and cant be installed!
+
+It may contains `;` characters (even like this `;;;;`). Example:
+
+  - one;
+  - two;
+  - three;
+
+... and they are properly handled by the automatic description formatter!
+
+See also: https://www.debian.org/doc/debian-policy/ch-controlfields.html#description]])
+
+if(RunCMake_SUBTEST_SUFFIX STREQUAL "CPACK_DEBIAN_PACKAGE_DESCRIPTION")
+  if(PACKAGING_TYPE STREQUAL "COMPONENT")
+    set(CPACK_DEBIAN_SATU_DESCRIPTION "${_description}")
+    set(CPACK_DEBIAN_DUA_DESCRIPTION "${_description}")
+  else()
+    set(CPACK_DEBIAN_PACKAGE_DESCRIPTION "${_description}")
+  endif()
+
+elseif(RunCMake_SUBTEST_SUFFIX STREQUAL "CPACK_PACKAGE_DESCRIPTION")
+  # NOTE Documented fallback variable
+  if(PACKAGING_TYPE STREQUAL "COMPONENT")
+    set(CPACK_COMPONENT_SATU_DESCRIPTION "${_description}")
+    set(CPACK_COMPONENT_DUA_DESCRIPTION "${_description}")
+  else()
+    set(CPACK_PACKAGE_DESCRIPTION "${_description}")
+  endif()
+
+elseif(RunCMake_SUBTEST_SUFFIX STREQUAL "CPACK_PACKAGE_DESCRIPTION_FILE")
+  # NOTE Getting the description from the file
+  set(_file "${CMAKE_CURRENT_BINARY_DIR}/description.txt")
+  file(WRITE "${_file}" "${_description}")
+  set(CPACK_PACKAGE_DESCRIPTION_FILE "${_file}")
+
+endif()
+
+# kate: indent-width 2;
diff --git a/Tests/RunCMake/CPack/tests/PER_COMPONENT_FIELDS/VerifyResult.cmake b/Tests/RunCMake/CPack/tests/PER_COMPONENT_FIELDS/VerifyResult.cmake
index b4bdb61..c47b40e 100644
--- a/Tests/RunCMake/CPack/tests/PER_COMPONENT_FIELDS/VerifyResult.cmake
+++ b/Tests/RunCMake/CPack/tests/PER_COMPONENT_FIELDS/VerifyResult.cmake
@@ -8,6 +8,9 @@ endfunction()
 if(GENERATOR_TYPE STREQUAL "DEB")
   set(name_ "Package")
   set(group_ "Section")
+  # NOTE For a Debian package the first line of the `Description`
+  # field is generated by CMake and gonna be ignored
+  set(ignore_rest_cond_ ".*\n")
 elseif(GENERATOR_TYPE STREQUAL "RPM")
   set(name_ "Name")
   set(group_ "Group")
@@ -33,6 +36,6 @@ if(GENERATOR_TYPE STREQUAL "RPM")
 endif()
 
 # check package description
-checkPackageInfo_("description" "${FOUND_FILE_1}" ".*Description${whitespaces_}:${whitespaces_}Description for pkg_1")
-checkPackageInfo_("description" "${FOUND_FILE_2}" ".*Description${whitespaces_}:${whitespaces_}Description for pkg_2")
-checkPackageInfo_("description" "${FOUND_FILE_3}" ".*Description${whitespaces_}:${whitespaces_}Description for pkg_3")
+checkPackageInfo_("description" "${FOUND_FILE_1}" ".*Description${whitespaces_}:${ignore_rest_cond_}${whitespaces_}Description for pkg_1")
+checkPackageInfo_("description" "${FOUND_FILE_2}" ".*Description${whitespaces_}:${ignore_rest_cond_}${whitespaces_}Description for pkg_2")
+checkPackageInfo_("description" "${FOUND_FILE_3}" ".*Description${whitespaces_}:${ignore_rest_cond_}${whitespaces_}Description for pkg_3")